1 /* Perform the semantic phase of parsing, i.e., the process of 2 building tree structure, checking semantic consistency, and 3 building RTL. These routines are used both during actual parsing 4 and during the instantiation of template functions. 5 6 Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 7 2008, 2009, 2010, 2011, 2012 Free Software Foundation, Inc. 8 Written by Mark Mitchell (mmitchell@usa.net) based on code found 9 formerly in parse.y and pt.c. 10 11 This file is part of GCC. 12 13 GCC is free software; you can redistribute it and/or modify it 14 under the terms of the GNU General Public License as published by 15 the Free Software Foundation; either version 3, or (at your option) 16 any later version. 17 18 GCC is distributed in the hope that it will be useful, but 19 WITHOUT ANY WARRANTY; without even the implied warranty of 20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 21 General Public License for more details. 22 23 You should have received a copy of the GNU General Public License 24 along with GCC; see the file COPYING3. If not see 25 <http://www.gnu.org/licenses/>. */ 26 27 #include "config.h" 28 #include "system.h" 29 #include "coretypes.h" 30 #include "tm.h" 31 #include "tree.h" 32 #include "cp-tree.h" 33 #include "c-family/c-common.h" 34 #include "c-family/c-objc.h" 35 #include "tree-inline.h" 36 #include "intl.h" 37 #include "toplev.h" 38 #include "flags.h" 39 #include "output.h" 40 #include "timevar.h" 41 #include "diagnostic.h" 42 #include "cgraph.h" 43 #include "tree-iterator.h" 44 #include "vec.h" 45 #include "target.h" 46 #include "gimple.h" 47 #include "bitmap.h" 48 49 /* There routines provide a modular interface to perform many parsing 50 operations. They may therefore be used during actual parsing, or 51 during template instantiation, which may be regarded as a 52 degenerate form of parsing. */ 53 54 static tree maybe_convert_cond (tree); 55 static tree finalize_nrv_r (tree *, int *, void *); 56 static tree capture_decltype (tree); 57 58 59 /* Deferred Access Checking Overview 60 --------------------------------- 61 62 Most C++ expressions and declarations require access checking 63 to be performed during parsing. However, in several cases, 64 this has to be treated differently. 65 66 For member declarations, access checking has to be deferred 67 until more information about the declaration is known. For 68 example: 69 70 class A { 71 typedef int X; 72 public: 73 X f(); 74 }; 75 76 A::X A::f(); 77 A::X g(); 78 79 When we are parsing the function return type `A::X', we don't 80 really know if this is allowed until we parse the function name. 81 82 Furthermore, some contexts require that access checking is 83 never performed at all. These include class heads, and template 84 instantiations. 85 86 Typical use of access checking functions is described here: 87 88 1. When we enter a context that requires certain access checking 89 mode, the function `push_deferring_access_checks' is called with 90 DEFERRING argument specifying the desired mode. Access checking 91 may be performed immediately (dk_no_deferred), deferred 92 (dk_deferred), or not performed (dk_no_check). 93 94 2. When a declaration such as a type, or a variable, is encountered, 95 the function `perform_or_defer_access_check' is called. It 96 maintains a VEC of all deferred checks. 97 98 3. The global `current_class_type' or `current_function_decl' is then 99 setup by the parser. `enforce_access' relies on these information 100 to check access. 101 102 4. Upon exiting the context mentioned in step 1, 103 `perform_deferred_access_checks' is called to check all declaration 104 stored in the VEC. `pop_deferring_access_checks' is then 105 called to restore the previous access checking mode. 106 107 In case of parsing error, we simply call `pop_deferring_access_checks' 108 without `perform_deferred_access_checks'. */ 109 110 typedef struct GTY(()) deferred_access { 111 /* A VEC representing name-lookups for which we have deferred 112 checking access controls. We cannot check the accessibility of 113 names used in a decl-specifier-seq until we know what is being 114 declared because code like: 115 116 class A { 117 class B {}; 118 B* f(); 119 } 120 121 A::B* A::f() { return 0; } 122 123 is valid, even though `A::B' is not generally accessible. */ 124 VEC (deferred_access_check,gc)* GTY(()) deferred_access_checks; 125 126 /* The current mode of access checks. */ 127 enum deferring_kind deferring_access_checks_kind; 128 129 } deferred_access; 130 DEF_VEC_O (deferred_access); 131 DEF_VEC_ALLOC_O (deferred_access,gc); 132 133 /* Data for deferred access checking. */ 134 static GTY(()) VEC(deferred_access,gc) *deferred_access_stack; 135 static GTY(()) unsigned deferred_access_no_check; 136 137 /* Save the current deferred access states and start deferred 138 access checking iff DEFER_P is true. */ 139 140 void 141 push_deferring_access_checks (deferring_kind deferring) 142 { 143 /* For context like template instantiation, access checking 144 disabling applies to all nested context. */ 145 if (deferred_access_no_check || deferring == dk_no_check) 146 deferred_access_no_check++; 147 else 148 { 149 deferred_access *ptr; 150 151 ptr = VEC_safe_push (deferred_access, gc, deferred_access_stack, NULL); 152 ptr->deferred_access_checks = NULL; 153 ptr->deferring_access_checks_kind = deferring; 154 } 155 } 156 157 /* Resume deferring access checks again after we stopped doing 158 this previously. */ 159 160 void 161 resume_deferring_access_checks (void) 162 { 163 if (!deferred_access_no_check) 164 VEC_last (deferred_access, deferred_access_stack) 165 ->deferring_access_checks_kind = dk_deferred; 166 } 167 168 /* Stop deferring access checks. */ 169 170 void 171 stop_deferring_access_checks (void) 172 { 173 if (!deferred_access_no_check) 174 VEC_last (deferred_access, deferred_access_stack) 175 ->deferring_access_checks_kind = dk_no_deferred; 176 } 177 178 /* Discard the current deferred access checks and restore the 179 previous states. */ 180 181 void 182 pop_deferring_access_checks (void) 183 { 184 if (deferred_access_no_check) 185 deferred_access_no_check--; 186 else 187 VEC_pop (deferred_access, deferred_access_stack); 188 } 189 190 /* Returns a TREE_LIST representing the deferred checks. 191 The TREE_PURPOSE of each node is the type through which the 192 access occurred; the TREE_VALUE is the declaration named. 193 */ 194 195 VEC (deferred_access_check,gc)* 196 get_deferred_access_checks (void) 197 { 198 if (deferred_access_no_check) 199 return NULL; 200 else 201 return (VEC_last (deferred_access, deferred_access_stack) 202 ->deferred_access_checks); 203 } 204 205 /* Take current deferred checks and combine with the 206 previous states if we also defer checks previously. 207 Otherwise perform checks now. */ 208 209 void 210 pop_to_parent_deferring_access_checks (void) 211 { 212 if (deferred_access_no_check) 213 deferred_access_no_check--; 214 else 215 { 216 VEC (deferred_access_check,gc) *checks; 217 deferred_access *ptr; 218 219 checks = (VEC_last (deferred_access, deferred_access_stack) 220 ->deferred_access_checks); 221 222 VEC_pop (deferred_access, deferred_access_stack); 223 ptr = VEC_last (deferred_access, deferred_access_stack); 224 if (ptr->deferring_access_checks_kind == dk_no_deferred) 225 { 226 /* Check access. */ 227 perform_access_checks (checks); 228 } 229 else 230 { 231 /* Merge with parent. */ 232 int i, j; 233 deferred_access_check *chk, *probe; 234 235 FOR_EACH_VEC_ELT (deferred_access_check, checks, i, chk) 236 { 237 FOR_EACH_VEC_ELT (deferred_access_check, 238 ptr->deferred_access_checks, j, probe) 239 { 240 if (probe->binfo == chk->binfo && 241 probe->decl == chk->decl && 242 probe->diag_decl == chk->diag_decl) 243 goto found; 244 } 245 /* Insert into parent's checks. */ 246 VEC_safe_push (deferred_access_check, gc, 247 ptr->deferred_access_checks, chk); 248 found:; 249 } 250 } 251 } 252 } 253 254 /* Perform the access checks in CHECKS. The TREE_PURPOSE of each node 255 is the BINFO indicating the qualifying scope used to access the 256 DECL node stored in the TREE_VALUE of the node. */ 257 258 void 259 perform_access_checks (VEC (deferred_access_check,gc)* checks) 260 { 261 int i; 262 deferred_access_check *chk; 263 264 if (!checks) 265 return; 266 267 FOR_EACH_VEC_ELT (deferred_access_check, checks, i, chk) 268 enforce_access (chk->binfo, chk->decl, chk->diag_decl); 269 } 270 271 /* Perform the deferred access checks. 272 273 After performing the checks, we still have to keep the list 274 `deferred_access_stack->deferred_access_checks' since we may want 275 to check access for them again later in a different context. 276 For example: 277 278 class A { 279 typedef int X; 280 static X a; 281 }; 282 A::X A::a, x; // No error for `A::a', error for `x' 283 284 We have to perform deferred access of `A::X', first with `A::a', 285 next with `x'. */ 286 287 void 288 perform_deferred_access_checks (void) 289 { 290 perform_access_checks (get_deferred_access_checks ()); 291 } 292 293 /* Defer checking the accessibility of DECL, when looked up in 294 BINFO. DIAG_DECL is the declaration to use to print diagnostics. */ 295 296 void 297 perform_or_defer_access_check (tree binfo, tree decl, tree diag_decl) 298 { 299 int i; 300 deferred_access *ptr; 301 deferred_access_check *chk; 302 deferred_access_check *new_access; 303 304 305 /* Exit if we are in a context that no access checking is performed. 306 */ 307 if (deferred_access_no_check) 308 return; 309 310 gcc_assert (TREE_CODE (binfo) == TREE_BINFO); 311 312 ptr = VEC_last (deferred_access, deferred_access_stack); 313 314 /* If we are not supposed to defer access checks, just check now. */ 315 if (ptr->deferring_access_checks_kind == dk_no_deferred) 316 { 317 enforce_access (binfo, decl, diag_decl); 318 return; 319 } 320 321 /* See if we are already going to perform this check. */ 322 FOR_EACH_VEC_ELT (deferred_access_check, 323 ptr->deferred_access_checks, i, chk) 324 { 325 if (chk->decl == decl && chk->binfo == binfo && 326 chk->diag_decl == diag_decl) 327 { 328 return; 329 } 330 } 331 /* If not, record the check. */ 332 new_access = 333 VEC_safe_push (deferred_access_check, gc, 334 ptr->deferred_access_checks, 0); 335 new_access->binfo = binfo; 336 new_access->decl = decl; 337 new_access->diag_decl = diag_decl; 338 } 339 340 /* Used by build_over_call in LOOKUP_SPECULATIVE mode: return whether DECL 341 is accessible in BINFO, and possibly complain if not. If we're not 342 checking access, everything is accessible. */ 343 344 bool 345 speculative_access_check (tree binfo, tree decl, tree diag_decl, 346 bool complain) 347 { 348 if (deferred_access_no_check) 349 return true; 350 351 /* If we're checking for implicit delete, we don't want access 352 control errors. */ 353 if (!accessible_p (binfo, decl, true)) 354 { 355 /* Unless we're under maybe_explain_implicit_delete. */ 356 if (complain) 357 enforce_access (binfo, decl, diag_decl); 358 return false; 359 } 360 361 return true; 362 } 363 364 /* Returns nonzero if the current statement is a full expression, 365 i.e. temporaries created during that statement should be destroyed 366 at the end of the statement. */ 367 368 int 369 stmts_are_full_exprs_p (void) 370 { 371 return current_stmt_tree ()->stmts_are_full_exprs_p; 372 } 373 374 /* T is a statement. Add it to the statement-tree. This is the C++ 375 version. The C/ObjC frontends have a slightly different version of 376 this function. */ 377 378 tree 379 add_stmt (tree t) 380 { 381 enum tree_code code = TREE_CODE (t); 382 383 if (EXPR_P (t) && code != LABEL_EXPR) 384 { 385 if (!EXPR_HAS_LOCATION (t)) 386 SET_EXPR_LOCATION (t, input_location); 387 388 /* When we expand a statement-tree, we must know whether or not the 389 statements are full-expressions. We record that fact here. */ 390 STMT_IS_FULL_EXPR_P (t) = stmts_are_full_exprs_p (); 391 } 392 393 /* Add T to the statement-tree. Non-side-effect statements need to be 394 recorded during statement expressions. */ 395 gcc_checking_assert (!VEC_empty (tree, stmt_list_stack)); 396 append_to_statement_list_force (t, &cur_stmt_list); 397 398 return t; 399 } 400 401 /* Returns the stmt_tree to which statements are currently being added. */ 402 403 stmt_tree 404 current_stmt_tree (void) 405 { 406 return (cfun 407 ? &cfun->language->base.x_stmt_tree 408 : &scope_chain->x_stmt_tree); 409 } 410 411 /* If statements are full expressions, wrap STMT in a CLEANUP_POINT_EXPR. */ 412 413 static tree 414 maybe_cleanup_point_expr (tree expr) 415 { 416 if (!processing_template_decl && stmts_are_full_exprs_p ()) 417 expr = fold_build_cleanup_point_expr (TREE_TYPE (expr), expr); 418 return expr; 419 } 420 421 /* Like maybe_cleanup_point_expr except have the type of the new expression be 422 void so we don't need to create a temporary variable to hold the inner 423 expression. The reason why we do this is because the original type might be 424 an aggregate and we cannot create a temporary variable for that type. */ 425 426 tree 427 maybe_cleanup_point_expr_void (tree expr) 428 { 429 if (!processing_template_decl && stmts_are_full_exprs_p ()) 430 expr = fold_build_cleanup_point_expr (void_type_node, expr); 431 return expr; 432 } 433 434 435 436 /* Create a declaration statement for the declaration given by the DECL. */ 437 438 void 439 add_decl_expr (tree decl) 440 { 441 tree r = build_stmt (input_location, DECL_EXPR, decl); 442 if (DECL_INITIAL (decl) 443 || (DECL_SIZE (decl) && TREE_SIDE_EFFECTS (DECL_SIZE (decl)))) 444 r = maybe_cleanup_point_expr_void (r); 445 add_stmt (r); 446 } 447 448 /* Finish a scope. */ 449 450 tree 451 do_poplevel (tree stmt_list) 452 { 453 tree block = NULL; 454 455 if (stmts_are_full_exprs_p ()) 456 block = poplevel (kept_level_p (), 1, 0); 457 458 stmt_list = pop_stmt_list (stmt_list); 459 460 if (!processing_template_decl) 461 { 462 stmt_list = c_build_bind_expr (input_location, block, stmt_list); 463 /* ??? See c_end_compound_stmt re statement expressions. */ 464 } 465 466 return stmt_list; 467 } 468 469 /* Begin a new scope. */ 470 471 static tree 472 do_pushlevel (scope_kind sk) 473 { 474 tree ret = push_stmt_list (); 475 if (stmts_are_full_exprs_p ()) 476 begin_scope (sk, NULL); 477 return ret; 478 } 479 480 /* Queue a cleanup. CLEANUP is an expression/statement to be executed 481 when the current scope is exited. EH_ONLY is true when this is not 482 meant to apply to normal control flow transfer. */ 483 484 void 485 push_cleanup (tree decl, tree cleanup, bool eh_only) 486 { 487 tree stmt = build_stmt (input_location, CLEANUP_STMT, NULL, cleanup, decl); 488 CLEANUP_EH_ONLY (stmt) = eh_only; 489 add_stmt (stmt); 490 CLEANUP_BODY (stmt) = push_stmt_list (); 491 } 492 493 /* Begin a conditional that might contain a declaration. When generating 494 normal code, we want the declaration to appear before the statement 495 containing the conditional. When generating template code, we want the 496 conditional to be rendered as the raw DECL_EXPR. */ 497 498 static void 499 begin_cond (tree *cond_p) 500 { 501 if (processing_template_decl) 502 *cond_p = push_stmt_list (); 503 } 504 505 /* Finish such a conditional. */ 506 507 static void 508 finish_cond (tree *cond_p, tree expr) 509 { 510 if (processing_template_decl) 511 { 512 tree cond = pop_stmt_list (*cond_p); 513 if (TREE_CODE (cond) == DECL_EXPR) 514 expr = cond; 515 516 if (check_for_bare_parameter_packs (expr)) 517 *cond_p = error_mark_node; 518 } 519 *cond_p = expr; 520 } 521 522 /* If *COND_P specifies a conditional with a declaration, transform the 523 loop such that 524 while (A x = 42) { } 525 for (; A x = 42;) { } 526 becomes 527 while (true) { A x = 42; if (!x) break; } 528 for (;;) { A x = 42; if (!x) break; } 529 The statement list for BODY will be empty if the conditional did 530 not declare anything. */ 531 532 static void 533 simplify_loop_decl_cond (tree *cond_p, tree body) 534 { 535 tree cond, if_stmt; 536 537 if (!TREE_SIDE_EFFECTS (body)) 538 return; 539 540 cond = *cond_p; 541 *cond_p = boolean_true_node; 542 543 if_stmt = begin_if_stmt (); 544 cond = cp_build_unary_op (TRUTH_NOT_EXPR, cond, 0, tf_warning_or_error); 545 finish_if_stmt_cond (cond, if_stmt); 546 finish_break_stmt (); 547 finish_then_clause (if_stmt); 548 finish_if_stmt (if_stmt); 549 } 550 551 /* Finish a goto-statement. */ 552 553 tree 554 finish_goto_stmt (tree destination) 555 { 556 if (TREE_CODE (destination) == IDENTIFIER_NODE) 557 destination = lookup_label (destination); 558 559 /* We warn about unused labels with -Wunused. That means we have to 560 mark the used labels as used. */ 561 if (TREE_CODE (destination) == LABEL_DECL) 562 TREE_USED (destination) = 1; 563 else 564 { 565 destination = mark_rvalue_use (destination); 566 if (!processing_template_decl) 567 { 568 destination = cp_convert (ptr_type_node, destination); 569 if (error_operand_p (destination)) 570 return NULL_TREE; 571 } 572 } 573 574 check_goto (destination); 575 576 return add_stmt (build_stmt (input_location, GOTO_EXPR, destination)); 577 } 578 579 /* COND is the condition-expression for an if, while, etc., 580 statement. Convert it to a boolean value, if appropriate. 581 In addition, verify sequence points if -Wsequence-point is enabled. */ 582 583 static tree 584 maybe_convert_cond (tree cond) 585 { 586 /* Empty conditions remain empty. */ 587 if (!cond) 588 return NULL_TREE; 589 590 /* Wait until we instantiate templates before doing conversion. */ 591 if (processing_template_decl) 592 return cond; 593 594 if (warn_sequence_point) 595 verify_sequence_points (cond); 596 597 /* Do the conversion. */ 598 cond = convert_from_reference (cond); 599 600 if (TREE_CODE (cond) == MODIFY_EXPR 601 && !TREE_NO_WARNING (cond) 602 && warn_parentheses) 603 { 604 warning (OPT_Wparentheses, 605 "suggest parentheses around assignment used as truth value"); 606 TREE_NO_WARNING (cond) = 1; 607 } 608 609 return condition_conversion (cond); 610 } 611 612 /* Finish an expression-statement, whose EXPRESSION is as indicated. */ 613 614 tree 615 finish_expr_stmt (tree expr) 616 { 617 tree r = NULL_TREE; 618 619 if (expr != NULL_TREE) 620 { 621 if (!processing_template_decl) 622 { 623 if (warn_sequence_point) 624 verify_sequence_points (expr); 625 expr = convert_to_void (expr, ICV_STATEMENT, tf_warning_or_error); 626 } 627 else if (!type_dependent_expression_p (expr)) 628 convert_to_void (build_non_dependent_expr (expr), ICV_STATEMENT, 629 tf_warning_or_error); 630 631 if (check_for_bare_parameter_packs (expr)) 632 expr = error_mark_node; 633 634 /* Simplification of inner statement expressions, compound exprs, 635 etc can result in us already having an EXPR_STMT. */ 636 if (TREE_CODE (expr) != CLEANUP_POINT_EXPR) 637 { 638 if (TREE_CODE (expr) != EXPR_STMT) 639 expr = build_stmt (input_location, EXPR_STMT, expr); 640 expr = maybe_cleanup_point_expr_void (expr); 641 } 642 643 r = add_stmt (expr); 644 } 645 646 finish_stmt (); 647 648 return r; 649 } 650 651 652 /* Begin an if-statement. Returns a newly created IF_STMT if 653 appropriate. */ 654 655 tree 656 begin_if_stmt (void) 657 { 658 tree r, scope; 659 scope = do_pushlevel (sk_cond); 660 r = build_stmt (input_location, IF_STMT, NULL_TREE, 661 NULL_TREE, NULL_TREE, scope); 662 begin_cond (&IF_COND (r)); 663 return r; 664 } 665 666 /* Process the COND of an if-statement, which may be given by 667 IF_STMT. */ 668 669 void 670 finish_if_stmt_cond (tree cond, tree if_stmt) 671 { 672 finish_cond (&IF_COND (if_stmt), maybe_convert_cond (cond)); 673 add_stmt (if_stmt); 674 THEN_CLAUSE (if_stmt) = push_stmt_list (); 675 } 676 677 /* Finish the then-clause of an if-statement, which may be given by 678 IF_STMT. */ 679 680 tree 681 finish_then_clause (tree if_stmt) 682 { 683 THEN_CLAUSE (if_stmt) = pop_stmt_list (THEN_CLAUSE (if_stmt)); 684 return if_stmt; 685 } 686 687 /* Begin the else-clause of an if-statement. */ 688 689 void 690 begin_else_clause (tree if_stmt) 691 { 692 ELSE_CLAUSE (if_stmt) = push_stmt_list (); 693 } 694 695 /* Finish the else-clause of an if-statement, which may be given by 696 IF_STMT. */ 697 698 void 699 finish_else_clause (tree if_stmt) 700 { 701 ELSE_CLAUSE (if_stmt) = pop_stmt_list (ELSE_CLAUSE (if_stmt)); 702 } 703 704 /* Finish an if-statement. */ 705 706 void 707 finish_if_stmt (tree if_stmt) 708 { 709 tree scope = IF_SCOPE (if_stmt); 710 IF_SCOPE (if_stmt) = NULL; 711 add_stmt (do_poplevel (scope)); 712 finish_stmt (); 713 } 714 715 /* Begin a while-statement. Returns a newly created WHILE_STMT if 716 appropriate. */ 717 718 tree 719 begin_while_stmt (void) 720 { 721 tree r; 722 r = build_stmt (input_location, WHILE_STMT, NULL_TREE, NULL_TREE); 723 add_stmt (r); 724 WHILE_BODY (r) = do_pushlevel (sk_block); 725 begin_cond (&WHILE_COND (r)); 726 return r; 727 } 728 729 /* Process the COND of a while-statement, which may be given by 730 WHILE_STMT. */ 731 732 void 733 finish_while_stmt_cond (tree cond, tree while_stmt) 734 { 735 finish_cond (&WHILE_COND (while_stmt), maybe_convert_cond (cond)); 736 simplify_loop_decl_cond (&WHILE_COND (while_stmt), WHILE_BODY (while_stmt)); 737 } 738 739 /* Finish a while-statement, which may be given by WHILE_STMT. */ 740 741 void 742 finish_while_stmt (tree while_stmt) 743 { 744 WHILE_BODY (while_stmt) = do_poplevel (WHILE_BODY (while_stmt)); 745 finish_stmt (); 746 } 747 748 /* Begin a do-statement. Returns a newly created DO_STMT if 749 appropriate. */ 750 751 tree 752 begin_do_stmt (void) 753 { 754 tree r = build_stmt (input_location, DO_STMT, NULL_TREE, NULL_TREE); 755 add_stmt (r); 756 DO_BODY (r) = push_stmt_list (); 757 return r; 758 } 759 760 /* Finish the body of a do-statement, which may be given by DO_STMT. */ 761 762 void 763 finish_do_body (tree do_stmt) 764 { 765 tree body = DO_BODY (do_stmt) = pop_stmt_list (DO_BODY (do_stmt)); 766 767 if (TREE_CODE (body) == STATEMENT_LIST && STATEMENT_LIST_TAIL (body)) 768 body = STATEMENT_LIST_TAIL (body)->stmt; 769 770 if (IS_EMPTY_STMT (body)) 771 warning (OPT_Wempty_body, 772 "suggest explicit braces around empty body in %<do%> statement"); 773 } 774 775 /* Finish a do-statement, which may be given by DO_STMT, and whose 776 COND is as indicated. */ 777 778 void 779 finish_do_stmt (tree cond, tree do_stmt) 780 { 781 cond = maybe_convert_cond (cond); 782 DO_COND (do_stmt) = cond; 783 finish_stmt (); 784 } 785 786 /* Finish a return-statement. The EXPRESSION returned, if any, is as 787 indicated. */ 788 789 tree 790 finish_return_stmt (tree expr) 791 { 792 tree r; 793 bool no_warning; 794 795 expr = check_return_expr (expr, &no_warning); 796 797 if (flag_openmp && !check_omp_return ()) 798 return error_mark_node; 799 if (!processing_template_decl) 800 { 801 if (warn_sequence_point) 802 verify_sequence_points (expr); 803 804 if (DECL_DESTRUCTOR_P (current_function_decl) 805 || (DECL_CONSTRUCTOR_P (current_function_decl) 806 && targetm.cxx.cdtor_returns_this ())) 807 { 808 /* Similarly, all destructors must run destructors for 809 base-classes before returning. So, all returns in a 810 destructor get sent to the DTOR_LABEL; finish_function emits 811 code to return a value there. */ 812 return finish_goto_stmt (cdtor_label); 813 } 814 } 815 816 r = build_stmt (input_location, RETURN_EXPR, expr); 817 TREE_NO_WARNING (r) |= no_warning; 818 r = maybe_cleanup_point_expr_void (r); 819 r = add_stmt (r); 820 finish_stmt (); 821 822 return r; 823 } 824 825 /* Begin the scope of a for-statement or a range-for-statement. 826 Both the returned trees are to be used in a call to 827 begin_for_stmt or begin_range_for_stmt. */ 828 829 tree 830 begin_for_scope (tree *init) 831 { 832 tree scope = NULL_TREE; 833 if (flag_new_for_scope > 0) 834 scope = do_pushlevel (sk_for); 835 836 if (processing_template_decl) 837 *init = push_stmt_list (); 838 else 839 *init = NULL_TREE; 840 841 return scope; 842 } 843 844 /* Begin a for-statement. Returns a new FOR_STMT. 845 SCOPE and INIT should be the return of begin_for_scope, 846 or both NULL_TREE */ 847 848 tree 849 begin_for_stmt (tree scope, tree init) 850 { 851 tree r; 852 853 r = build_stmt (input_location, FOR_STMT, NULL_TREE, NULL_TREE, 854 NULL_TREE, NULL_TREE, NULL_TREE); 855 856 if (scope == NULL_TREE) 857 { 858 gcc_assert (!init || !(flag_new_for_scope > 0)); 859 if (!init) 860 scope = begin_for_scope (&init); 861 } 862 FOR_INIT_STMT (r) = init; 863 FOR_SCOPE (r) = scope; 864 865 return r; 866 } 867 868 /* Finish the for-init-statement of a for-statement, which may be 869 given by FOR_STMT. */ 870 871 void 872 finish_for_init_stmt (tree for_stmt) 873 { 874 if (processing_template_decl) 875 FOR_INIT_STMT (for_stmt) = pop_stmt_list (FOR_INIT_STMT (for_stmt)); 876 add_stmt (for_stmt); 877 FOR_BODY (for_stmt) = do_pushlevel (sk_block); 878 begin_cond (&FOR_COND (for_stmt)); 879 } 880 881 /* Finish the COND of a for-statement, which may be given by 882 FOR_STMT. */ 883 884 void 885 finish_for_cond (tree cond, tree for_stmt) 886 { 887 finish_cond (&FOR_COND (for_stmt), maybe_convert_cond (cond)); 888 simplify_loop_decl_cond (&FOR_COND (for_stmt), FOR_BODY (for_stmt)); 889 } 890 891 /* Finish the increment-EXPRESSION in a for-statement, which may be 892 given by FOR_STMT. */ 893 894 void 895 finish_for_expr (tree expr, tree for_stmt) 896 { 897 if (!expr) 898 return; 899 /* If EXPR is an overloaded function, issue an error; there is no 900 context available to use to perform overload resolution. */ 901 if (type_unknown_p (expr)) 902 { 903 cxx_incomplete_type_error (expr, TREE_TYPE (expr)); 904 expr = error_mark_node; 905 } 906 if (!processing_template_decl) 907 { 908 if (warn_sequence_point) 909 verify_sequence_points (expr); 910 expr = convert_to_void (expr, ICV_THIRD_IN_FOR, 911 tf_warning_or_error); 912 } 913 else if (!type_dependent_expression_p (expr)) 914 convert_to_void (build_non_dependent_expr (expr), ICV_THIRD_IN_FOR, 915 tf_warning_or_error); 916 expr = maybe_cleanup_point_expr_void (expr); 917 if (check_for_bare_parameter_packs (expr)) 918 expr = error_mark_node; 919 FOR_EXPR (for_stmt) = expr; 920 } 921 922 /* Finish the body of a for-statement, which may be given by 923 FOR_STMT. The increment-EXPR for the loop must be 924 provided. 925 It can also finish RANGE_FOR_STMT. */ 926 927 void 928 finish_for_stmt (tree for_stmt) 929 { 930 if (TREE_CODE (for_stmt) == RANGE_FOR_STMT) 931 RANGE_FOR_BODY (for_stmt) = do_poplevel (RANGE_FOR_BODY (for_stmt)); 932 else 933 FOR_BODY (for_stmt) = do_poplevel (FOR_BODY (for_stmt)); 934 935 /* Pop the scope for the body of the loop. */ 936 if (flag_new_for_scope > 0) 937 { 938 tree scope; 939 tree *scope_ptr = (TREE_CODE (for_stmt) == RANGE_FOR_STMT 940 ? &RANGE_FOR_SCOPE (for_stmt) 941 : &FOR_SCOPE (for_stmt)); 942 scope = *scope_ptr; 943 *scope_ptr = NULL; 944 add_stmt (do_poplevel (scope)); 945 } 946 947 finish_stmt (); 948 } 949 950 /* Begin a range-for-statement. Returns a new RANGE_FOR_STMT. 951 SCOPE and INIT should be the return of begin_for_scope, 952 or both NULL_TREE . 953 To finish it call finish_for_stmt(). */ 954 955 tree 956 begin_range_for_stmt (tree scope, tree init) 957 { 958 tree r; 959 960 r = build_stmt (input_location, RANGE_FOR_STMT, 961 NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE); 962 963 if (scope == NULL_TREE) 964 { 965 gcc_assert (!init || !(flag_new_for_scope > 0)); 966 if (!init) 967 scope = begin_for_scope (&init); 968 } 969 970 /* RANGE_FOR_STMTs do not use nor save the init tree, so we 971 pop it now. */ 972 if (init) 973 pop_stmt_list (init); 974 RANGE_FOR_SCOPE (r) = scope; 975 976 return r; 977 } 978 979 /* Finish the head of a range-based for statement, which may 980 be given by RANGE_FOR_STMT. DECL must be the declaration 981 and EXPR must be the loop expression. */ 982 983 void 984 finish_range_for_decl (tree range_for_stmt, tree decl, tree expr) 985 { 986 RANGE_FOR_DECL (range_for_stmt) = decl; 987 RANGE_FOR_EXPR (range_for_stmt) = expr; 988 add_stmt (range_for_stmt); 989 RANGE_FOR_BODY (range_for_stmt) = do_pushlevel (sk_block); 990 } 991 992 /* Finish a break-statement. */ 993 994 tree 995 finish_break_stmt (void) 996 { 997 /* In switch statements break is sometimes stylistically used after 998 a return statement. This can lead to spurious warnings about 999 control reaching the end of a non-void function when it is 1000 inlined. Note that we are calling block_may_fallthru with 1001 language specific tree nodes; this works because 1002 block_may_fallthru returns true when given something it does not 1003 understand. */ 1004 if (!block_may_fallthru (cur_stmt_list)) 1005 return void_zero_node; 1006 return add_stmt (build_stmt (input_location, BREAK_STMT)); 1007 } 1008 1009 /* Finish a continue-statement. */ 1010 1011 tree 1012 finish_continue_stmt (void) 1013 { 1014 return add_stmt (build_stmt (input_location, CONTINUE_STMT)); 1015 } 1016 1017 /* Begin a switch-statement. Returns a new SWITCH_STMT if 1018 appropriate. */ 1019 1020 tree 1021 begin_switch_stmt (void) 1022 { 1023 tree r, scope; 1024 1025 scope = do_pushlevel (sk_cond); 1026 r = build_stmt (input_location, SWITCH_STMT, NULL_TREE, NULL_TREE, NULL_TREE, scope); 1027 1028 begin_cond (&SWITCH_STMT_COND (r)); 1029 1030 return r; 1031 } 1032 1033 /* Finish the cond of a switch-statement. */ 1034 1035 void 1036 finish_switch_cond (tree cond, tree switch_stmt) 1037 { 1038 tree orig_type = NULL; 1039 if (!processing_template_decl) 1040 { 1041 /* Convert the condition to an integer or enumeration type. */ 1042 cond = build_expr_type_conversion (WANT_INT | WANT_ENUM, cond, true); 1043 if (cond == NULL_TREE) 1044 { 1045 error ("switch quantity not an integer"); 1046 cond = error_mark_node; 1047 } 1048 orig_type = TREE_TYPE (cond); 1049 if (cond != error_mark_node) 1050 { 1051 /* [stmt.switch] 1052 1053 Integral promotions are performed. */ 1054 cond = perform_integral_promotions (cond); 1055 cond = maybe_cleanup_point_expr (cond); 1056 } 1057 } 1058 if (check_for_bare_parameter_packs (cond)) 1059 cond = error_mark_node; 1060 else if (!processing_template_decl && warn_sequence_point) 1061 verify_sequence_points (cond); 1062 1063 finish_cond (&SWITCH_STMT_COND (switch_stmt), cond); 1064 SWITCH_STMT_TYPE (switch_stmt) = orig_type; 1065 add_stmt (switch_stmt); 1066 push_switch (switch_stmt); 1067 SWITCH_STMT_BODY (switch_stmt) = push_stmt_list (); 1068 } 1069 1070 /* Finish the body of a switch-statement, which may be given by 1071 SWITCH_STMT. The COND to switch on is indicated. */ 1072 1073 void 1074 finish_switch_stmt (tree switch_stmt) 1075 { 1076 tree scope; 1077 1078 SWITCH_STMT_BODY (switch_stmt) = 1079 pop_stmt_list (SWITCH_STMT_BODY (switch_stmt)); 1080 pop_switch (); 1081 finish_stmt (); 1082 1083 scope = SWITCH_STMT_SCOPE (switch_stmt); 1084 SWITCH_STMT_SCOPE (switch_stmt) = NULL; 1085 add_stmt (do_poplevel (scope)); 1086 } 1087 1088 /* Begin a try-block. Returns a newly-created TRY_BLOCK if 1089 appropriate. */ 1090 1091 tree 1092 begin_try_block (void) 1093 { 1094 tree r = build_stmt (input_location, TRY_BLOCK, NULL_TREE, NULL_TREE); 1095 add_stmt (r); 1096 TRY_STMTS (r) = push_stmt_list (); 1097 return r; 1098 } 1099 1100 /* Likewise, for a function-try-block. The block returned in 1101 *COMPOUND_STMT is an artificial outer scope, containing the 1102 function-try-block. */ 1103 1104 tree 1105 begin_function_try_block (tree *compound_stmt) 1106 { 1107 tree r; 1108 /* This outer scope does not exist in the C++ standard, but we need 1109 a place to put __FUNCTION__ and similar variables. */ 1110 *compound_stmt = begin_compound_stmt (0); 1111 r = begin_try_block (); 1112 FN_TRY_BLOCK_P (r) = 1; 1113 return r; 1114 } 1115 1116 /* Finish a try-block, which may be given by TRY_BLOCK. */ 1117 1118 void 1119 finish_try_block (tree try_block) 1120 { 1121 TRY_STMTS (try_block) = pop_stmt_list (TRY_STMTS (try_block)); 1122 TRY_HANDLERS (try_block) = push_stmt_list (); 1123 } 1124 1125 /* Finish the body of a cleanup try-block, which may be given by 1126 TRY_BLOCK. */ 1127 1128 void 1129 finish_cleanup_try_block (tree try_block) 1130 { 1131 TRY_STMTS (try_block) = pop_stmt_list (TRY_STMTS (try_block)); 1132 } 1133 1134 /* Finish an implicitly generated try-block, with a cleanup is given 1135 by CLEANUP. */ 1136 1137 void 1138 finish_cleanup (tree cleanup, tree try_block) 1139 { 1140 TRY_HANDLERS (try_block) = cleanup; 1141 CLEANUP_P (try_block) = 1; 1142 } 1143 1144 /* Likewise, for a function-try-block. */ 1145 1146 void 1147 finish_function_try_block (tree try_block) 1148 { 1149 finish_try_block (try_block); 1150 /* FIXME : something queer about CTOR_INITIALIZER somehow following 1151 the try block, but moving it inside. */ 1152 in_function_try_handler = 1; 1153 } 1154 1155 /* Finish a handler-sequence for a try-block, which may be given by 1156 TRY_BLOCK. */ 1157 1158 void 1159 finish_handler_sequence (tree try_block) 1160 { 1161 TRY_HANDLERS (try_block) = pop_stmt_list (TRY_HANDLERS (try_block)); 1162 check_handlers (TRY_HANDLERS (try_block)); 1163 } 1164 1165 /* Finish the handler-seq for a function-try-block, given by 1166 TRY_BLOCK. COMPOUND_STMT is the outer block created by 1167 begin_function_try_block. */ 1168 1169 void 1170 finish_function_handler_sequence (tree try_block, tree compound_stmt) 1171 { 1172 in_function_try_handler = 0; 1173 finish_handler_sequence (try_block); 1174 finish_compound_stmt (compound_stmt); 1175 } 1176 1177 /* Begin a handler. Returns a HANDLER if appropriate. */ 1178 1179 tree 1180 begin_handler (void) 1181 { 1182 tree r; 1183 1184 r = build_stmt (input_location, HANDLER, NULL_TREE, NULL_TREE); 1185 add_stmt (r); 1186 1187 /* Create a binding level for the eh_info and the exception object 1188 cleanup. */ 1189 HANDLER_BODY (r) = do_pushlevel (sk_catch); 1190 1191 return r; 1192 } 1193 1194 /* Finish the handler-parameters for a handler, which may be given by 1195 HANDLER. DECL is the declaration for the catch parameter, or NULL 1196 if this is a `catch (...)' clause. */ 1197 1198 void 1199 finish_handler_parms (tree decl, tree handler) 1200 { 1201 tree type = NULL_TREE; 1202 if (processing_template_decl) 1203 { 1204 if (decl) 1205 { 1206 decl = pushdecl (decl); 1207 decl = push_template_decl (decl); 1208 HANDLER_PARMS (handler) = decl; 1209 type = TREE_TYPE (decl); 1210 } 1211 } 1212 else 1213 type = expand_start_catch_block (decl); 1214 HANDLER_TYPE (handler) = type; 1215 if (!processing_template_decl && type) 1216 mark_used (eh_type_info (type)); 1217 } 1218 1219 /* Finish a handler, which may be given by HANDLER. The BLOCKs are 1220 the return value from the matching call to finish_handler_parms. */ 1221 1222 void 1223 finish_handler (tree handler) 1224 { 1225 if (!processing_template_decl) 1226 expand_end_catch_block (); 1227 HANDLER_BODY (handler) = do_poplevel (HANDLER_BODY (handler)); 1228 } 1229 1230 /* Begin a compound statement. FLAGS contains some bits that control the 1231 behavior and context. If BCS_NO_SCOPE is set, the compound statement 1232 does not define a scope. If BCS_FN_BODY is set, this is the outermost 1233 block of a function. If BCS_TRY_BLOCK is set, this is the block 1234 created on behalf of a TRY statement. Returns a token to be passed to 1235 finish_compound_stmt. */ 1236 1237 tree 1238 begin_compound_stmt (unsigned int flags) 1239 { 1240 tree r; 1241 1242 if (flags & BCS_NO_SCOPE) 1243 { 1244 r = push_stmt_list (); 1245 STATEMENT_LIST_NO_SCOPE (r) = 1; 1246 1247 /* Normally, we try hard to keep the BLOCK for a statement-expression. 1248 But, if it's a statement-expression with a scopeless block, there's 1249 nothing to keep, and we don't want to accidentally keep a block 1250 *inside* the scopeless block. */ 1251 keep_next_level (false); 1252 } 1253 else 1254 r = do_pushlevel (flags & BCS_TRY_BLOCK ? sk_try : sk_block); 1255 1256 /* When processing a template, we need to remember where the braces were, 1257 so that we can set up identical scopes when instantiating the template 1258 later. BIND_EXPR is a handy candidate for this. 1259 Note that do_poplevel won't create a BIND_EXPR itself here (and thus 1260 result in nested BIND_EXPRs), since we don't build BLOCK nodes when 1261 processing templates. */ 1262 if (processing_template_decl) 1263 { 1264 r = build3 (BIND_EXPR, NULL, NULL, r, NULL); 1265 BIND_EXPR_TRY_BLOCK (r) = (flags & BCS_TRY_BLOCK) != 0; 1266 BIND_EXPR_BODY_BLOCK (r) = (flags & BCS_FN_BODY) != 0; 1267 TREE_SIDE_EFFECTS (r) = 1; 1268 } 1269 1270 return r; 1271 } 1272 1273 /* Finish a compound-statement, which is given by STMT. */ 1274 1275 void 1276 finish_compound_stmt (tree stmt) 1277 { 1278 if (TREE_CODE (stmt) == BIND_EXPR) 1279 { 1280 tree body = do_poplevel (BIND_EXPR_BODY (stmt)); 1281 /* If the STATEMENT_LIST is empty and this BIND_EXPR isn't special, 1282 discard the BIND_EXPR so it can be merged with the containing 1283 STATEMENT_LIST. */ 1284 if (TREE_CODE (body) == STATEMENT_LIST 1285 && STATEMENT_LIST_HEAD (body) == NULL 1286 && !BIND_EXPR_BODY_BLOCK (stmt) 1287 && !BIND_EXPR_TRY_BLOCK (stmt)) 1288 stmt = body; 1289 else 1290 BIND_EXPR_BODY (stmt) = body; 1291 } 1292 else if (STATEMENT_LIST_NO_SCOPE (stmt)) 1293 stmt = pop_stmt_list (stmt); 1294 else 1295 { 1296 /* Destroy any ObjC "super" receivers that may have been 1297 created. */ 1298 objc_clear_super_receiver (); 1299 1300 stmt = do_poplevel (stmt); 1301 } 1302 1303 /* ??? See c_end_compound_stmt wrt statement expressions. */ 1304 add_stmt (stmt); 1305 finish_stmt (); 1306 } 1307 1308 /* Finish an asm-statement, whose components are a STRING, some 1309 OUTPUT_OPERANDS, some INPUT_OPERANDS, some CLOBBERS and some 1310 LABELS. Also note whether the asm-statement should be 1311 considered volatile. */ 1312 1313 tree 1314 finish_asm_stmt (int volatile_p, tree string, tree output_operands, 1315 tree input_operands, tree clobbers, tree labels) 1316 { 1317 tree r; 1318 tree t; 1319 int ninputs = list_length (input_operands); 1320 int noutputs = list_length (output_operands); 1321 1322 if (!processing_template_decl) 1323 { 1324 const char *constraint; 1325 const char **oconstraints; 1326 bool allows_mem, allows_reg, is_inout; 1327 tree operand; 1328 int i; 1329 1330 oconstraints = XALLOCAVEC (const char *, noutputs); 1331 1332 string = resolve_asm_operand_names (string, output_operands, 1333 input_operands, labels); 1334 1335 for (i = 0, t = output_operands; t; t = TREE_CHAIN (t), ++i) 1336 { 1337 operand = TREE_VALUE (t); 1338 1339 /* ??? Really, this should not be here. Users should be using a 1340 proper lvalue, dammit. But there's a long history of using 1341 casts in the output operands. In cases like longlong.h, this 1342 becomes a primitive form of typechecking -- if the cast can be 1343 removed, then the output operand had a type of the proper width; 1344 otherwise we'll get an error. Gross, but ... */ 1345 STRIP_NOPS (operand); 1346 1347 operand = mark_lvalue_use (operand); 1348 1349 if (!lvalue_or_else (operand, lv_asm, tf_warning_or_error)) 1350 operand = error_mark_node; 1351 1352 if (operand != error_mark_node 1353 && (TREE_READONLY (operand) 1354 || CP_TYPE_CONST_P (TREE_TYPE (operand)) 1355 /* Functions are not modifiable, even though they are 1356 lvalues. */ 1357 || TREE_CODE (TREE_TYPE (operand)) == FUNCTION_TYPE 1358 || TREE_CODE (TREE_TYPE (operand)) == METHOD_TYPE 1359 /* If it's an aggregate and any field is const, then it is 1360 effectively const. */ 1361 || (CLASS_TYPE_P (TREE_TYPE (operand)) 1362 && C_TYPE_FIELDS_READONLY (TREE_TYPE (operand))))) 1363 cxx_readonly_error (operand, lv_asm); 1364 1365 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (t))); 1366 oconstraints[i] = constraint; 1367 1368 if (parse_output_constraint (&constraint, i, ninputs, noutputs, 1369 &allows_mem, &allows_reg, &is_inout)) 1370 { 1371 /* If the operand is going to end up in memory, 1372 mark it addressable. */ 1373 if (!allows_reg && !cxx_mark_addressable (operand)) 1374 operand = error_mark_node; 1375 } 1376 else 1377 operand = error_mark_node; 1378 1379 TREE_VALUE (t) = operand; 1380 } 1381 1382 for (i = 0, t = input_operands; t; ++i, t = TREE_CHAIN (t)) 1383 { 1384 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (t))); 1385 operand = decay_conversion (TREE_VALUE (t)); 1386 1387 /* If the type of the operand hasn't been determined (e.g., 1388 because it involves an overloaded function), then issue 1389 an error message. There's no context available to 1390 resolve the overloading. */ 1391 if (TREE_TYPE (operand) == unknown_type_node) 1392 { 1393 error ("type of asm operand %qE could not be determined", 1394 TREE_VALUE (t)); 1395 operand = error_mark_node; 1396 } 1397 1398 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0, 1399 oconstraints, &allows_mem, &allows_reg)) 1400 { 1401 /* If the operand is going to end up in memory, 1402 mark it addressable. */ 1403 if (!allows_reg && allows_mem) 1404 { 1405 /* Strip the nops as we allow this case. FIXME, this really 1406 should be rejected or made deprecated. */ 1407 STRIP_NOPS (operand); 1408 if (!cxx_mark_addressable (operand)) 1409 operand = error_mark_node; 1410 } 1411 } 1412 else 1413 operand = error_mark_node; 1414 1415 TREE_VALUE (t) = operand; 1416 } 1417 } 1418 1419 r = build_stmt (input_location, ASM_EXPR, string, 1420 output_operands, input_operands, 1421 clobbers, labels); 1422 ASM_VOLATILE_P (r) = volatile_p || noutputs == 0; 1423 r = maybe_cleanup_point_expr_void (r); 1424 return add_stmt (r); 1425 } 1426 1427 /* Finish a label with the indicated NAME. Returns the new label. */ 1428 1429 tree 1430 finish_label_stmt (tree name) 1431 { 1432 tree decl = define_label (input_location, name); 1433 1434 if (decl == error_mark_node) 1435 return error_mark_node; 1436 1437 add_stmt (build_stmt (input_location, LABEL_EXPR, decl)); 1438 1439 return decl; 1440 } 1441 1442 /* Finish a series of declarations for local labels. G++ allows users 1443 to declare "local" labels, i.e., labels with scope. This extension 1444 is useful when writing code involving statement-expressions. */ 1445 1446 void 1447 finish_label_decl (tree name) 1448 { 1449 if (!at_function_scope_p ()) 1450 { 1451 error ("__label__ declarations are only allowed in function scopes"); 1452 return; 1453 } 1454 1455 add_decl_expr (declare_local_label (name)); 1456 } 1457 1458 /* When DECL goes out of scope, make sure that CLEANUP is executed. */ 1459 1460 void 1461 finish_decl_cleanup (tree decl, tree cleanup) 1462 { 1463 push_cleanup (decl, cleanup, false); 1464 } 1465 1466 /* If the current scope exits with an exception, run CLEANUP. */ 1467 1468 void 1469 finish_eh_cleanup (tree cleanup) 1470 { 1471 push_cleanup (NULL, cleanup, true); 1472 } 1473 1474 /* The MEM_INITS is a list of mem-initializers, in reverse of the 1475 order they were written by the user. Each node is as for 1476 emit_mem_initializers. */ 1477 1478 void 1479 finish_mem_initializers (tree mem_inits) 1480 { 1481 /* Reorder the MEM_INITS so that they are in the order they appeared 1482 in the source program. */ 1483 mem_inits = nreverse (mem_inits); 1484 1485 if (processing_template_decl) 1486 { 1487 tree mem; 1488 1489 for (mem = mem_inits; mem; mem = TREE_CHAIN (mem)) 1490 { 1491 /* If the TREE_PURPOSE is a TYPE_PACK_EXPANSION, skip the 1492 check for bare parameter packs in the TREE_VALUE, because 1493 any parameter packs in the TREE_VALUE have already been 1494 bound as part of the TREE_PURPOSE. See 1495 make_pack_expansion for more information. */ 1496 if (TREE_CODE (TREE_PURPOSE (mem)) != TYPE_PACK_EXPANSION 1497 && check_for_bare_parameter_packs (TREE_VALUE (mem))) 1498 TREE_VALUE (mem) = error_mark_node; 1499 } 1500 1501 add_stmt (build_min_nt (CTOR_INITIALIZER, mem_inits)); 1502 } 1503 else 1504 emit_mem_initializers (mem_inits); 1505 } 1506 1507 /* Finish a parenthesized expression EXPR. */ 1508 1509 tree 1510 finish_parenthesized_expr (tree expr) 1511 { 1512 if (EXPR_P (expr)) 1513 /* This inhibits warnings in c_common_truthvalue_conversion. */ 1514 TREE_NO_WARNING (expr) = 1; 1515 1516 if (TREE_CODE (expr) == OFFSET_REF 1517 || TREE_CODE (expr) == SCOPE_REF) 1518 /* [expr.unary.op]/3 The qualified id of a pointer-to-member must not be 1519 enclosed in parentheses. */ 1520 PTRMEM_OK_P (expr) = 0; 1521 1522 if (TREE_CODE (expr) == STRING_CST) 1523 PAREN_STRING_LITERAL_P (expr) = 1; 1524 1525 return expr; 1526 } 1527 1528 /* Finish a reference to a non-static data member (DECL) that is not 1529 preceded by `.' or `->'. */ 1530 1531 tree 1532 finish_non_static_data_member (tree decl, tree object, tree qualifying_scope) 1533 { 1534 gcc_assert (TREE_CODE (decl) == FIELD_DECL); 1535 1536 if (!object) 1537 { 1538 tree scope = qualifying_scope; 1539 if (scope == NULL_TREE) 1540 scope = context_for_name_lookup (decl); 1541 object = maybe_dummy_object (scope, NULL); 1542 } 1543 1544 if (object == error_mark_node) 1545 return error_mark_node; 1546 1547 /* DR 613: Can use non-static data members without an associated 1548 object in sizeof/decltype/alignof. */ 1549 if (is_dummy_object (object) && cp_unevaluated_operand == 0 1550 && (!processing_template_decl || !current_class_ref)) 1551 { 1552 if (current_function_decl 1553 && DECL_STATIC_FUNCTION_P (current_function_decl)) 1554 error ("invalid use of member %q+D in static member function", decl); 1555 else 1556 error ("invalid use of non-static data member %q+D", decl); 1557 error ("from this location"); 1558 1559 return error_mark_node; 1560 } 1561 1562 if (current_class_ptr) 1563 TREE_USED (current_class_ptr) = 1; 1564 if (processing_template_decl && !qualifying_scope) 1565 { 1566 tree type = TREE_TYPE (decl); 1567 1568 if (TREE_CODE (type) == REFERENCE_TYPE) 1569 /* Quals on the object don't matter. */; 1570 else 1571 { 1572 /* Set the cv qualifiers. */ 1573 int quals = cp_type_quals (TREE_TYPE (object)); 1574 1575 if (DECL_MUTABLE_P (decl)) 1576 quals &= ~TYPE_QUAL_CONST; 1577 1578 quals |= cp_type_quals (TREE_TYPE (decl)); 1579 type = cp_build_qualified_type (type, quals); 1580 } 1581 1582 return (convert_from_reference 1583 (build_min (COMPONENT_REF, type, object, decl, NULL_TREE))); 1584 } 1585 /* If PROCESSING_TEMPLATE_DECL is nonzero here, then 1586 QUALIFYING_SCOPE is also non-null. Wrap this in a SCOPE_REF 1587 for now. */ 1588 else if (processing_template_decl) 1589 return build_qualified_name (TREE_TYPE (decl), 1590 qualifying_scope, 1591 DECL_NAME (decl), 1592 /*template_p=*/false); 1593 else 1594 { 1595 tree access_type = TREE_TYPE (object); 1596 1597 perform_or_defer_access_check (TYPE_BINFO (access_type), decl, 1598 decl); 1599 1600 /* If the data member was named `C::M', convert `*this' to `C' 1601 first. */ 1602 if (qualifying_scope) 1603 { 1604 tree binfo = NULL_TREE; 1605 object = build_scoped_ref (object, qualifying_scope, 1606 &binfo); 1607 } 1608 1609 return build_class_member_access_expr (object, decl, 1610 /*access_path=*/NULL_TREE, 1611 /*preserve_reference=*/false, 1612 tf_warning_or_error); 1613 } 1614 } 1615 1616 /* If we are currently parsing a template and we encountered a typedef 1617 TYPEDEF_DECL that is being accessed though CONTEXT, this function 1618 adds the typedef to a list tied to the current template. 1619 At tempate instantiatin time, that list is walked and access check 1620 performed for each typedef. 1621 LOCATION is the location of the usage point of TYPEDEF_DECL. */ 1622 1623 void 1624 add_typedef_to_current_template_for_access_check (tree typedef_decl, 1625 tree context, 1626 location_t location) 1627 { 1628 tree template_info = NULL; 1629 tree cs = current_scope (); 1630 1631 if (!is_typedef_decl (typedef_decl) 1632 || !context 1633 || !CLASS_TYPE_P (context) 1634 || !cs) 1635 return; 1636 1637 if (CLASS_TYPE_P (cs) || TREE_CODE (cs) == FUNCTION_DECL) 1638 template_info = get_template_info (cs); 1639 1640 if (template_info 1641 && TI_TEMPLATE (template_info) 1642 && !currently_open_class (context)) 1643 append_type_to_template_for_access_check (cs, typedef_decl, 1644 context, location); 1645 } 1646 1647 /* DECL was the declaration to which a qualified-id resolved. Issue 1648 an error message if it is not accessible. If OBJECT_TYPE is 1649 non-NULL, we have just seen `x->' or `x.' and OBJECT_TYPE is the 1650 type of `*x', or `x', respectively. If the DECL was named as 1651 `A::B' then NESTED_NAME_SPECIFIER is `A'. */ 1652 1653 void 1654 check_accessibility_of_qualified_id (tree decl, 1655 tree object_type, 1656 tree nested_name_specifier) 1657 { 1658 tree scope; 1659 tree qualifying_type = NULL_TREE; 1660 1661 /* If we are parsing a template declaration and if decl is a typedef, 1662 add it to a list tied to the template. 1663 At template instantiation time, that list will be walked and 1664 access check performed. */ 1665 add_typedef_to_current_template_for_access_check (decl, 1666 nested_name_specifier 1667 ? nested_name_specifier 1668 : DECL_CONTEXT (decl), 1669 input_location); 1670 1671 /* If we're not checking, return immediately. */ 1672 if (deferred_access_no_check) 1673 return; 1674 1675 /* Determine the SCOPE of DECL. */ 1676 scope = context_for_name_lookup (decl); 1677 /* If the SCOPE is not a type, then DECL is not a member. */ 1678 if (!TYPE_P (scope)) 1679 return; 1680 /* Compute the scope through which DECL is being accessed. */ 1681 if (object_type 1682 /* OBJECT_TYPE might not be a class type; consider: 1683 1684 class A { typedef int I; }; 1685 I *p; 1686 p->A::I::~I(); 1687 1688 In this case, we will have "A::I" as the DECL, but "I" as the 1689 OBJECT_TYPE. */ 1690 && CLASS_TYPE_P (object_type) 1691 && DERIVED_FROM_P (scope, object_type)) 1692 /* If we are processing a `->' or `.' expression, use the type of the 1693 left-hand side. */ 1694 qualifying_type = object_type; 1695 else if (nested_name_specifier) 1696 { 1697 /* If the reference is to a non-static member of the 1698 current class, treat it as if it were referenced through 1699 `this'. */ 1700 if (DECL_NONSTATIC_MEMBER_P (decl) 1701 && current_class_ptr 1702 && DERIVED_FROM_P (scope, current_class_type)) 1703 qualifying_type = current_class_type; 1704 /* Otherwise, use the type indicated by the 1705 nested-name-specifier. */ 1706 else 1707 qualifying_type = nested_name_specifier; 1708 } 1709 else 1710 /* Otherwise, the name must be from the current class or one of 1711 its bases. */ 1712 qualifying_type = currently_open_derived_class (scope); 1713 1714 if (qualifying_type 1715 /* It is possible for qualifying type to be a TEMPLATE_TYPE_PARM 1716 or similar in a default argument value. */ 1717 && CLASS_TYPE_P (qualifying_type) 1718 && !dependent_type_p (qualifying_type)) 1719 perform_or_defer_access_check (TYPE_BINFO (qualifying_type), decl, 1720 decl); 1721 } 1722 1723 /* EXPR is the result of a qualified-id. The QUALIFYING_CLASS was the 1724 class named to the left of the "::" operator. DONE is true if this 1725 expression is a complete postfix-expression; it is false if this 1726 expression is followed by '->', '[', '(', etc. ADDRESS_P is true 1727 iff this expression is the operand of '&'. TEMPLATE_P is true iff 1728 the qualified-id was of the form "A::template B". TEMPLATE_ARG_P 1729 is true iff this qualified name appears as a template argument. */ 1730 1731 tree 1732 finish_qualified_id_expr (tree qualifying_class, 1733 tree expr, 1734 bool done, 1735 bool address_p, 1736 bool template_p, 1737 bool template_arg_p) 1738 { 1739 gcc_assert (TYPE_P (qualifying_class)); 1740 1741 if (error_operand_p (expr)) 1742 return error_mark_node; 1743 1744 if (DECL_P (expr) || BASELINK_P (expr)) 1745 mark_used (expr); 1746 1747 if (template_p) 1748 check_template_keyword (expr); 1749 1750 /* If EXPR occurs as the operand of '&', use special handling that 1751 permits a pointer-to-member. */ 1752 if (address_p && done) 1753 { 1754 if (TREE_CODE (expr) == SCOPE_REF) 1755 expr = TREE_OPERAND (expr, 1); 1756 expr = build_offset_ref (qualifying_class, expr, 1757 /*address_p=*/true); 1758 return expr; 1759 } 1760 1761 /* Within the scope of a class, turn references to non-static 1762 members into expression of the form "this->...". */ 1763 if (template_arg_p) 1764 /* But, within a template argument, we do not want make the 1765 transformation, as there is no "this" pointer. */ 1766 ; 1767 else if (TREE_CODE (expr) == FIELD_DECL) 1768 { 1769 push_deferring_access_checks (dk_no_check); 1770 expr = finish_non_static_data_member (expr, NULL_TREE, 1771 qualifying_class); 1772 pop_deferring_access_checks (); 1773 } 1774 else if (BASELINK_P (expr) && !processing_template_decl) 1775 { 1776 tree ob; 1777 1778 /* See if any of the functions are non-static members. */ 1779 /* If so, the expression may be relative to 'this'. */ 1780 if (!shared_member_p (expr) 1781 && (ob = maybe_dummy_object (qualifying_class, NULL), 1782 !is_dummy_object (ob))) 1783 expr = (build_class_member_access_expr 1784 (ob, 1785 expr, 1786 BASELINK_ACCESS_BINFO (expr), 1787 /*preserve_reference=*/false, 1788 tf_warning_or_error)); 1789 else if (done) 1790 /* The expression is a qualified name whose address is not 1791 being taken. */ 1792 expr = build_offset_ref (qualifying_class, expr, /*address_p=*/false); 1793 } 1794 1795 return expr; 1796 } 1797 1798 /* Begin a statement-expression. The value returned must be passed to 1799 finish_stmt_expr. */ 1800 1801 tree 1802 begin_stmt_expr (void) 1803 { 1804 return push_stmt_list (); 1805 } 1806 1807 /* Process the final expression of a statement expression. EXPR can be 1808 NULL, if the final expression is empty. Return a STATEMENT_LIST 1809 containing all the statements in the statement-expression, or 1810 ERROR_MARK_NODE if there was an error. */ 1811 1812 tree 1813 finish_stmt_expr_expr (tree expr, tree stmt_expr) 1814 { 1815 if (error_operand_p (expr)) 1816 { 1817 /* The type of the statement-expression is the type of the last 1818 expression. */ 1819 TREE_TYPE (stmt_expr) = error_mark_node; 1820 return error_mark_node; 1821 } 1822 1823 /* If the last statement does not have "void" type, then the value 1824 of the last statement is the value of the entire expression. */ 1825 if (expr) 1826 { 1827 tree type = TREE_TYPE (expr); 1828 1829 if (processing_template_decl) 1830 { 1831 expr = build_stmt (input_location, EXPR_STMT, expr); 1832 expr = add_stmt (expr); 1833 /* Mark the last statement so that we can recognize it as such at 1834 template-instantiation time. */ 1835 EXPR_STMT_STMT_EXPR_RESULT (expr) = 1; 1836 } 1837 else if (VOID_TYPE_P (type)) 1838 { 1839 /* Just treat this like an ordinary statement. */ 1840 expr = finish_expr_stmt (expr); 1841 } 1842 else 1843 { 1844 /* It actually has a value we need to deal with. First, force it 1845 to be an rvalue so that we won't need to build up a copy 1846 constructor call later when we try to assign it to something. */ 1847 expr = force_rvalue (expr, tf_warning_or_error); 1848 if (error_operand_p (expr)) 1849 return error_mark_node; 1850 1851 /* Update for array-to-pointer decay. */ 1852 type = TREE_TYPE (expr); 1853 1854 /* Wrap it in a CLEANUP_POINT_EXPR and add it to the list like a 1855 normal statement, but don't convert to void or actually add 1856 the EXPR_STMT. */ 1857 if (TREE_CODE (expr) != CLEANUP_POINT_EXPR) 1858 expr = maybe_cleanup_point_expr (expr); 1859 add_stmt (expr); 1860 } 1861 1862 /* The type of the statement-expression is the type of the last 1863 expression. */ 1864 TREE_TYPE (stmt_expr) = type; 1865 } 1866 1867 return stmt_expr; 1868 } 1869 1870 /* Finish a statement-expression. EXPR should be the value returned 1871 by the previous begin_stmt_expr. Returns an expression 1872 representing the statement-expression. */ 1873 1874 tree 1875 finish_stmt_expr (tree stmt_expr, bool has_no_scope) 1876 { 1877 tree type; 1878 tree result; 1879 1880 if (error_operand_p (stmt_expr)) 1881 { 1882 pop_stmt_list (stmt_expr); 1883 return error_mark_node; 1884 } 1885 1886 gcc_assert (TREE_CODE (stmt_expr) == STATEMENT_LIST); 1887 1888 type = TREE_TYPE (stmt_expr); 1889 result = pop_stmt_list (stmt_expr); 1890 TREE_TYPE (result) = type; 1891 1892 if (processing_template_decl) 1893 { 1894 result = build_min (STMT_EXPR, type, result); 1895 TREE_SIDE_EFFECTS (result) = 1; 1896 STMT_EXPR_NO_SCOPE (result) = has_no_scope; 1897 } 1898 else if (CLASS_TYPE_P (type)) 1899 { 1900 /* Wrap the statement-expression in a TARGET_EXPR so that the 1901 temporary object created by the final expression is destroyed at 1902 the end of the full-expression containing the 1903 statement-expression. */ 1904 result = force_target_expr (type, result, tf_warning_or_error); 1905 } 1906 1907 return result; 1908 } 1909 1910 /* Returns the expression which provides the value of STMT_EXPR. */ 1911 1912 tree 1913 stmt_expr_value_expr (tree stmt_expr) 1914 { 1915 tree t = STMT_EXPR_STMT (stmt_expr); 1916 1917 if (TREE_CODE (t) == BIND_EXPR) 1918 t = BIND_EXPR_BODY (t); 1919 1920 if (TREE_CODE (t) == STATEMENT_LIST && STATEMENT_LIST_TAIL (t)) 1921 t = STATEMENT_LIST_TAIL (t)->stmt; 1922 1923 if (TREE_CODE (t) == EXPR_STMT) 1924 t = EXPR_STMT_EXPR (t); 1925 1926 return t; 1927 } 1928 1929 /* Return TRUE iff EXPR_STMT is an empty list of 1930 expression statements. */ 1931 1932 bool 1933 empty_expr_stmt_p (tree expr_stmt) 1934 { 1935 tree body = NULL_TREE; 1936 1937 if (expr_stmt == void_zero_node) 1938 return true; 1939 1940 if (expr_stmt) 1941 { 1942 if (TREE_CODE (expr_stmt) == EXPR_STMT) 1943 body = EXPR_STMT_EXPR (expr_stmt); 1944 else if (TREE_CODE (expr_stmt) == STATEMENT_LIST) 1945 body = expr_stmt; 1946 } 1947 1948 if (body) 1949 { 1950 if (TREE_CODE (body) == STATEMENT_LIST) 1951 return tsi_end_p (tsi_start (body)); 1952 else 1953 return empty_expr_stmt_p (body); 1954 } 1955 return false; 1956 } 1957 1958 /* Perform Koenig lookup. FN is the postfix-expression representing 1959 the function (or functions) to call; ARGS are the arguments to the 1960 call; if INCLUDE_STD then the `std' namespace is automatically 1961 considered an associated namespace (used in range-based for loops). 1962 Returns the functions to be considered by overload resolution. */ 1963 1964 tree 1965 perform_koenig_lookup (tree fn, VEC(tree,gc) *args, bool include_std, 1966 tsubst_flags_t complain) 1967 { 1968 tree identifier = NULL_TREE; 1969 tree functions = NULL_TREE; 1970 tree tmpl_args = NULL_TREE; 1971 bool template_id = false; 1972 1973 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR) 1974 { 1975 /* Use a separate flag to handle null args. */ 1976 template_id = true; 1977 tmpl_args = TREE_OPERAND (fn, 1); 1978 fn = TREE_OPERAND (fn, 0); 1979 } 1980 1981 /* Find the name of the overloaded function. */ 1982 if (TREE_CODE (fn) == IDENTIFIER_NODE) 1983 identifier = fn; 1984 else if (is_overloaded_fn (fn)) 1985 { 1986 functions = fn; 1987 identifier = DECL_NAME (get_first_fn (functions)); 1988 } 1989 else if (DECL_P (fn)) 1990 { 1991 functions = fn; 1992 identifier = DECL_NAME (fn); 1993 } 1994 1995 /* A call to a namespace-scope function using an unqualified name. 1996 1997 Do Koenig lookup -- unless any of the arguments are 1998 type-dependent. */ 1999 if (!any_type_dependent_arguments_p (args) 2000 && !any_dependent_template_arguments_p (tmpl_args)) 2001 { 2002 fn = lookup_arg_dependent (identifier, functions, args, include_std); 2003 if (!fn) 2004 { 2005 /* The unqualified name could not be resolved. */ 2006 if (complain) 2007 fn = unqualified_fn_lookup_error (identifier); 2008 else 2009 fn = identifier; 2010 } 2011 } 2012 2013 if (fn && template_id) 2014 fn = build2 (TEMPLATE_ID_EXPR, unknown_type_node, fn, tmpl_args); 2015 2016 return fn; 2017 } 2018 2019 /* Generate an expression for `FN (ARGS)'. This may change the 2020 contents of ARGS. 2021 2022 If DISALLOW_VIRTUAL is true, the call to FN will be not generated 2023 as a virtual call, even if FN is virtual. (This flag is set when 2024 encountering an expression where the function name is explicitly 2025 qualified. For example a call to `X::f' never generates a virtual 2026 call.) 2027 2028 Returns code for the call. */ 2029 2030 tree 2031 finish_call_expr (tree fn, VEC(tree,gc) **args, bool disallow_virtual, 2032 bool koenig_p, tsubst_flags_t complain) 2033 { 2034 tree result; 2035 tree orig_fn; 2036 VEC(tree,gc) *orig_args = NULL; 2037 2038 if (fn == error_mark_node) 2039 return error_mark_node; 2040 2041 gcc_assert (!TYPE_P (fn)); 2042 2043 orig_fn = fn; 2044 2045 if (processing_template_decl) 2046 { 2047 /* If the call expression is dependent, build a CALL_EXPR node 2048 with no type; type_dependent_expression_p recognizes 2049 expressions with no type as being dependent. */ 2050 if (type_dependent_expression_p (fn) 2051 || any_type_dependent_arguments_p (*args) 2052 /* For a non-static member function that doesn't have an 2053 explicit object argument, we need to specifically 2054 test the type dependency of the "this" pointer because it 2055 is not included in *ARGS even though it is considered to 2056 be part of the list of arguments. Note that this is 2057 related to CWG issues 515 and 1005. */ 2058 || (TREE_CODE (fn) != COMPONENT_REF 2059 && non_static_member_function_p (fn) 2060 && current_class_ref 2061 && type_dependent_expression_p (current_class_ref))) 2062 { 2063 result = build_nt_call_vec (fn, *args); 2064 KOENIG_LOOKUP_P (result) = koenig_p; 2065 if (cfun) 2066 { 2067 do 2068 { 2069 tree fndecl = OVL_CURRENT (fn); 2070 if (TREE_CODE (fndecl) != FUNCTION_DECL 2071 || !TREE_THIS_VOLATILE (fndecl)) 2072 break; 2073 fn = OVL_NEXT (fn); 2074 } 2075 while (fn); 2076 if (!fn) 2077 current_function_returns_abnormally = 1; 2078 } 2079 return result; 2080 } 2081 orig_args = make_tree_vector_copy (*args); 2082 if (!BASELINK_P (fn) 2083 && TREE_CODE (fn) != PSEUDO_DTOR_EXPR 2084 && TREE_TYPE (fn) != unknown_type_node) 2085 fn = build_non_dependent_expr (fn); 2086 make_args_non_dependent (*args); 2087 } 2088 2089 if (TREE_CODE (fn) == COMPONENT_REF) 2090 { 2091 tree member = TREE_OPERAND (fn, 1); 2092 if (BASELINK_P (member)) 2093 { 2094 tree object = TREE_OPERAND (fn, 0); 2095 return build_new_method_call (object, member, 2096 args, NULL_TREE, 2097 (disallow_virtual 2098 ? LOOKUP_NORMAL | LOOKUP_NONVIRTUAL 2099 : LOOKUP_NORMAL), 2100 /*fn_p=*/NULL, 2101 complain); 2102 } 2103 } 2104 2105 if (is_overloaded_fn (fn)) 2106 fn = baselink_for_fns (fn); 2107 2108 result = NULL_TREE; 2109 if (BASELINK_P (fn)) 2110 { 2111 tree object; 2112 2113 /* A call to a member function. From [over.call.func]: 2114 2115 If the keyword this is in scope and refers to the class of 2116 that member function, or a derived class thereof, then the 2117 function call is transformed into a qualified function call 2118 using (*this) as the postfix-expression to the left of the 2119 . operator.... [Otherwise] a contrived object of type T 2120 becomes the implied object argument. 2121 2122 In this situation: 2123 2124 struct A { void f(); }; 2125 struct B : public A {}; 2126 struct C : public A { void g() { B::f(); }}; 2127 2128 "the class of that member function" refers to `A'. But 11.2 2129 [class.access.base] says that we need to convert 'this' to B* as 2130 part of the access, so we pass 'B' to maybe_dummy_object. */ 2131 2132 object = maybe_dummy_object (BINFO_TYPE (BASELINK_ACCESS_BINFO (fn)), 2133 NULL); 2134 2135 if (processing_template_decl) 2136 { 2137 if (type_dependent_expression_p (object)) 2138 { 2139 tree ret = build_nt_call_vec (orig_fn, orig_args); 2140 release_tree_vector (orig_args); 2141 return ret; 2142 } 2143 object = build_non_dependent_expr (object); 2144 } 2145 2146 result = build_new_method_call (object, fn, args, NULL_TREE, 2147 (disallow_virtual 2148 ? LOOKUP_NORMAL|LOOKUP_NONVIRTUAL 2149 : LOOKUP_NORMAL), 2150 /*fn_p=*/NULL, 2151 complain); 2152 } 2153 else if (is_overloaded_fn (fn)) 2154 { 2155 /* If the function is an overloaded builtin, resolve it. */ 2156 if (TREE_CODE (fn) == FUNCTION_DECL 2157 && (DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL 2158 || DECL_BUILT_IN_CLASS (fn) == BUILT_IN_MD)) 2159 result = resolve_overloaded_builtin (input_location, fn, *args); 2160 2161 if (!result) 2162 /* A call to a namespace-scope function. */ 2163 result = build_new_function_call (fn, args, koenig_p, complain); 2164 } 2165 else if (TREE_CODE (fn) == PSEUDO_DTOR_EXPR) 2166 { 2167 if (!VEC_empty (tree, *args)) 2168 error ("arguments to destructor are not allowed"); 2169 /* Mark the pseudo-destructor call as having side-effects so 2170 that we do not issue warnings about its use. */ 2171 result = build1 (NOP_EXPR, 2172 void_type_node, 2173 TREE_OPERAND (fn, 0)); 2174 TREE_SIDE_EFFECTS (result) = 1; 2175 } 2176 else if (CLASS_TYPE_P (TREE_TYPE (fn))) 2177 /* If the "function" is really an object of class type, it might 2178 have an overloaded `operator ()'. */ 2179 result = build_op_call (fn, args, complain); 2180 2181 if (!result) 2182 /* A call where the function is unknown. */ 2183 result = cp_build_function_call_vec (fn, args, complain); 2184 2185 if (processing_template_decl && result != error_mark_node) 2186 { 2187 if (TREE_CODE (result) == INDIRECT_REF) 2188 result = TREE_OPERAND (result, 0); 2189 result = build_call_vec (TREE_TYPE (result), orig_fn, orig_args); 2190 SET_EXPR_LOCATION (result, input_location); 2191 KOENIG_LOOKUP_P (result) = koenig_p; 2192 release_tree_vector (orig_args); 2193 result = convert_from_reference (result); 2194 } 2195 2196 if (koenig_p) 2197 { 2198 /* Free garbage OVERLOADs from arg-dependent lookup. */ 2199 tree next = NULL_TREE; 2200 for (fn = orig_fn; 2201 fn && TREE_CODE (fn) == OVERLOAD && OVL_ARG_DEPENDENT (fn); 2202 fn = next) 2203 { 2204 if (processing_template_decl) 2205 /* In a template, we'll re-use them at instantiation time. */ 2206 OVL_ARG_DEPENDENT (fn) = false; 2207 else 2208 { 2209 next = OVL_CHAIN (fn); 2210 ggc_free (fn); 2211 } 2212 } 2213 } 2214 2215 return result; 2216 } 2217 2218 /* Finish a call to a postfix increment or decrement or EXPR. (Which 2219 is indicated by CODE, which should be POSTINCREMENT_EXPR or 2220 POSTDECREMENT_EXPR.) */ 2221 2222 tree 2223 finish_increment_expr (tree expr, enum tree_code code) 2224 { 2225 return build_x_unary_op (code, expr, tf_warning_or_error); 2226 } 2227 2228 /* Finish a use of `this'. Returns an expression for `this'. */ 2229 2230 tree 2231 finish_this_expr (void) 2232 { 2233 tree result; 2234 2235 if (current_class_ptr) 2236 { 2237 tree type = TREE_TYPE (current_class_ref); 2238 2239 /* In a lambda expression, 'this' refers to the captured 'this'. */ 2240 if (LAMBDA_TYPE_P (type)) 2241 result = lambda_expr_this_capture (CLASSTYPE_LAMBDA_EXPR (type)); 2242 else 2243 result = current_class_ptr; 2244 2245 } 2246 else if (current_function_decl 2247 && DECL_STATIC_FUNCTION_P (current_function_decl)) 2248 { 2249 error ("%<this%> is unavailable for static member functions"); 2250 result = error_mark_node; 2251 } 2252 else 2253 { 2254 if (current_function_decl) 2255 error ("invalid use of %<this%> in non-member function"); 2256 else 2257 error ("invalid use of %<this%> at top level"); 2258 result = error_mark_node; 2259 } 2260 2261 return result; 2262 } 2263 2264 /* Finish a pseudo-destructor expression. If SCOPE is NULL, the 2265 expression was of the form `OBJECT.~DESTRUCTOR' where DESTRUCTOR is 2266 the TYPE for the type given. If SCOPE is non-NULL, the expression 2267 was of the form `OBJECT.SCOPE::~DESTRUCTOR'. */ 2268 2269 tree 2270 finish_pseudo_destructor_expr (tree object, tree scope, tree destructor) 2271 { 2272 if (object == error_mark_node || destructor == error_mark_node) 2273 return error_mark_node; 2274 2275 gcc_assert (TYPE_P (destructor)); 2276 2277 if (!processing_template_decl) 2278 { 2279 if (scope == error_mark_node) 2280 { 2281 error ("invalid qualifying scope in pseudo-destructor name"); 2282 return error_mark_node; 2283 } 2284 if (scope && TYPE_P (scope) && !check_dtor_name (scope, destructor)) 2285 { 2286 error ("qualified type %qT does not match destructor name ~%qT", 2287 scope, destructor); 2288 return error_mark_node; 2289 } 2290 2291 2292 /* [expr.pseudo] says both: 2293 2294 The type designated by the pseudo-destructor-name shall be 2295 the same as the object type. 2296 2297 and: 2298 2299 The cv-unqualified versions of the object type and of the 2300 type designated by the pseudo-destructor-name shall be the 2301 same type. 2302 2303 We implement the more generous second sentence, since that is 2304 what most other compilers do. */ 2305 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (object), 2306 destructor)) 2307 { 2308 error ("%qE is not of type %qT", object, destructor); 2309 return error_mark_node; 2310 } 2311 } 2312 2313 return build3 (PSEUDO_DTOR_EXPR, void_type_node, object, scope, destructor); 2314 } 2315 2316 /* Finish an expression of the form CODE EXPR. */ 2317 2318 tree 2319 finish_unary_op_expr (enum tree_code code, tree expr) 2320 { 2321 tree result = build_x_unary_op (code, expr, tf_warning_or_error); 2322 if (TREE_OVERFLOW_P (result) && !TREE_OVERFLOW_P (expr)) 2323 overflow_warning (input_location, result); 2324 2325 return result; 2326 } 2327 2328 /* Finish a compound-literal expression. TYPE is the type to which 2329 the CONSTRUCTOR in COMPOUND_LITERAL is being cast. */ 2330 2331 tree 2332 finish_compound_literal (tree type, tree compound_literal, 2333 tsubst_flags_t complain) 2334 { 2335 if (type == error_mark_node) 2336 return error_mark_node; 2337 2338 if (TREE_CODE (type) == REFERENCE_TYPE) 2339 { 2340 compound_literal 2341 = finish_compound_literal (TREE_TYPE (type), compound_literal, 2342 complain); 2343 return cp_build_c_cast (type, compound_literal, complain); 2344 } 2345 2346 if (!TYPE_OBJ_P (type)) 2347 { 2348 if (complain & tf_error) 2349 error ("compound literal of non-object type %qT", type); 2350 return error_mark_node; 2351 } 2352 2353 if (processing_template_decl) 2354 { 2355 TREE_TYPE (compound_literal) = type; 2356 /* Mark the expression as a compound literal. */ 2357 TREE_HAS_CONSTRUCTOR (compound_literal) = 1; 2358 return compound_literal; 2359 } 2360 2361 type = complete_type (type); 2362 2363 if (TYPE_NON_AGGREGATE_CLASS (type)) 2364 { 2365 /* Trying to deal with a CONSTRUCTOR instead of a TREE_LIST 2366 everywhere that deals with function arguments would be a pain, so 2367 just wrap it in a TREE_LIST. The parser set a flag so we know 2368 that it came from T{} rather than T({}). */ 2369 CONSTRUCTOR_IS_DIRECT_INIT (compound_literal) = 1; 2370 compound_literal = build_tree_list (NULL_TREE, compound_literal); 2371 return build_functional_cast (type, compound_literal, complain); 2372 } 2373 2374 if (TREE_CODE (type) == ARRAY_TYPE 2375 && check_array_initializer (NULL_TREE, type, compound_literal)) 2376 return error_mark_node; 2377 compound_literal = reshape_init (type, compound_literal, complain); 2378 if (SCALAR_TYPE_P (type) 2379 && !BRACE_ENCLOSED_INITIALIZER_P (compound_literal) 2380 && (complain & tf_warning_or_error)) 2381 check_narrowing (type, compound_literal); 2382 if (TREE_CODE (type) == ARRAY_TYPE 2383 && TYPE_DOMAIN (type) == NULL_TREE) 2384 { 2385 cp_complete_array_type_or_error (&type, compound_literal, 2386 false, complain); 2387 if (type == error_mark_node) 2388 return error_mark_node; 2389 } 2390 compound_literal = digest_init (type, compound_literal, complain); 2391 if (TREE_CODE (compound_literal) == CONSTRUCTOR) 2392 TREE_HAS_CONSTRUCTOR (compound_literal) = true; 2393 /* Put static/constant array temporaries in static variables, but always 2394 represent class temporaries with TARGET_EXPR so we elide copies. */ 2395 if ((!at_function_scope_p () || CP_TYPE_CONST_P (type)) 2396 && TREE_CODE (type) == ARRAY_TYPE 2397 && !TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type) 2398 && initializer_constant_valid_p (compound_literal, type)) 2399 { 2400 tree decl = create_temporary_var (type); 2401 DECL_INITIAL (decl) = compound_literal; 2402 TREE_STATIC (decl) = 1; 2403 if (literal_type_p (type) && CP_TYPE_CONST_NON_VOLATILE_P (type)) 2404 { 2405 /* 5.19 says that a constant expression can include an 2406 lvalue-rvalue conversion applied to "a glvalue of literal type 2407 that refers to a non-volatile temporary object initialized 2408 with a constant expression". Rather than try to communicate 2409 that this VAR_DECL is a temporary, just mark it constexpr. */ 2410 DECL_DECLARED_CONSTEXPR_P (decl) = true; 2411 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl) = true; 2412 TREE_CONSTANT (decl) = true; 2413 } 2414 cp_apply_type_quals_to_decl (cp_type_quals (type), decl); 2415 decl = pushdecl_top_level (decl); 2416 DECL_NAME (decl) = make_anon_name (); 2417 SET_DECL_ASSEMBLER_NAME (decl, DECL_NAME (decl)); 2418 return decl; 2419 } 2420 else 2421 return get_target_expr_sfinae (compound_literal, complain); 2422 } 2423 2424 /* Return the declaration for the function-name variable indicated by 2425 ID. */ 2426 2427 tree 2428 finish_fname (tree id) 2429 { 2430 tree decl; 2431 2432 decl = fname_decl (input_location, C_RID_CODE (id), id); 2433 if (processing_template_decl && current_function_decl) 2434 decl = DECL_NAME (decl); 2435 return decl; 2436 } 2437 2438 /* Finish a translation unit. */ 2439 2440 void 2441 finish_translation_unit (void) 2442 { 2443 /* In case there were missing closebraces, 2444 get us back to the global binding level. */ 2445 pop_everything (); 2446 while (current_namespace != global_namespace) 2447 pop_namespace (); 2448 2449 /* Do file scope __FUNCTION__ et al. */ 2450 finish_fname_decls (); 2451 } 2452 2453 /* Finish a template type parameter, specified as AGGR IDENTIFIER. 2454 Returns the parameter. */ 2455 2456 tree 2457 finish_template_type_parm (tree aggr, tree identifier) 2458 { 2459 if (aggr != class_type_node) 2460 { 2461 permerror (input_location, "template type parameters must use the keyword %<class%> or %<typename%>"); 2462 aggr = class_type_node; 2463 } 2464 2465 return build_tree_list (aggr, identifier); 2466 } 2467 2468 /* Finish a template template parameter, specified as AGGR IDENTIFIER. 2469 Returns the parameter. */ 2470 2471 tree 2472 finish_template_template_parm (tree aggr, tree identifier) 2473 { 2474 tree decl = build_decl (input_location, 2475 TYPE_DECL, identifier, NULL_TREE); 2476 tree tmpl = build_lang_decl (TEMPLATE_DECL, identifier, NULL_TREE); 2477 DECL_TEMPLATE_PARMS (tmpl) = current_template_parms; 2478 DECL_TEMPLATE_RESULT (tmpl) = decl; 2479 DECL_ARTIFICIAL (decl) = 1; 2480 end_template_decl (); 2481 2482 gcc_assert (DECL_TEMPLATE_PARMS (tmpl)); 2483 2484 check_default_tmpl_args (decl, DECL_TEMPLATE_PARMS (tmpl), 2485 /*is_primary=*/true, /*is_partial=*/false, 2486 /*is_friend=*/0); 2487 2488 return finish_template_type_parm (aggr, tmpl); 2489 } 2490 2491 /* ARGUMENT is the default-argument value for a template template 2492 parameter. If ARGUMENT is invalid, issue error messages and return 2493 the ERROR_MARK_NODE. Otherwise, ARGUMENT itself is returned. */ 2494 2495 tree 2496 check_template_template_default_arg (tree argument) 2497 { 2498 if (TREE_CODE (argument) != TEMPLATE_DECL 2499 && TREE_CODE (argument) != TEMPLATE_TEMPLATE_PARM 2500 && TREE_CODE (argument) != UNBOUND_CLASS_TEMPLATE) 2501 { 2502 if (TREE_CODE (argument) == TYPE_DECL) 2503 error ("invalid use of type %qT as a default value for a template " 2504 "template-parameter", TREE_TYPE (argument)); 2505 else 2506 error ("invalid default argument for a template template parameter"); 2507 return error_mark_node; 2508 } 2509 2510 return argument; 2511 } 2512 2513 /* Begin a class definition, as indicated by T. */ 2514 2515 tree 2516 begin_class_definition (tree t) 2517 { 2518 if (error_operand_p (t) || error_operand_p (TYPE_MAIN_DECL (t))) 2519 return error_mark_node; 2520 2521 if (processing_template_parmlist) 2522 { 2523 error ("definition of %q#T inside template parameter list", t); 2524 return error_mark_node; 2525 } 2526 2527 /* According to the C++ ABI, decimal classes defined in ISO/IEC TR 24733 2528 are passed the same as decimal scalar types. */ 2529 if (TREE_CODE (t) == RECORD_TYPE 2530 && !processing_template_decl) 2531 { 2532 tree ns = TYPE_CONTEXT (t); 2533 if (ns && TREE_CODE (ns) == NAMESPACE_DECL 2534 && DECL_CONTEXT (ns) == std_node 2535 && DECL_NAME (ns) 2536 && !strcmp (IDENTIFIER_POINTER (DECL_NAME (ns)), "decimal")) 2537 { 2538 const char *n = TYPE_NAME_STRING (t); 2539 if ((strcmp (n, "decimal32") == 0) 2540 || (strcmp (n, "decimal64") == 0) 2541 || (strcmp (n, "decimal128") == 0)) 2542 TYPE_TRANSPARENT_AGGR (t) = 1; 2543 } 2544 } 2545 2546 /* A non-implicit typename comes from code like: 2547 2548 template <typename T> struct A { 2549 template <typename U> struct A<T>::B ... 2550 2551 This is erroneous. */ 2552 else if (TREE_CODE (t) == TYPENAME_TYPE) 2553 { 2554 error ("invalid definition of qualified type %qT", t); 2555 t = error_mark_node; 2556 } 2557 2558 if (t == error_mark_node || ! MAYBE_CLASS_TYPE_P (t)) 2559 { 2560 t = make_class_type (RECORD_TYPE); 2561 pushtag (make_anon_name (), t, /*tag_scope=*/ts_current); 2562 } 2563 2564 if (TYPE_BEING_DEFINED (t)) 2565 { 2566 t = make_class_type (TREE_CODE (t)); 2567 pushtag (TYPE_IDENTIFIER (t), t, /*tag_scope=*/ts_current); 2568 } 2569 maybe_process_partial_specialization (t); 2570 pushclass (t); 2571 TYPE_BEING_DEFINED (t) = 1; 2572 2573 if (flag_pack_struct) 2574 { 2575 tree v; 2576 TYPE_PACKED (t) = 1; 2577 /* Even though the type is being defined for the first time 2578 here, there might have been a forward declaration, so there 2579 might be cv-qualified variants of T. */ 2580 for (v = TYPE_NEXT_VARIANT (t); v; v = TYPE_NEXT_VARIANT (v)) 2581 TYPE_PACKED (v) = 1; 2582 } 2583 /* Reset the interface data, at the earliest possible 2584 moment, as it might have been set via a class foo; 2585 before. */ 2586 if (! TYPE_ANONYMOUS_P (t)) 2587 { 2588 struct c_fileinfo *finfo = get_fileinfo (input_filename); 2589 CLASSTYPE_INTERFACE_ONLY (t) = finfo->interface_only; 2590 SET_CLASSTYPE_INTERFACE_UNKNOWN_X 2591 (t, finfo->interface_unknown); 2592 } 2593 reset_specialization(); 2594 2595 /* Make a declaration for this class in its own scope. */ 2596 build_self_reference (); 2597 2598 return t; 2599 } 2600 2601 /* Finish the member declaration given by DECL. */ 2602 2603 void 2604 finish_member_declaration (tree decl) 2605 { 2606 if (decl == error_mark_node || decl == NULL_TREE) 2607 return; 2608 2609 if (decl == void_type_node) 2610 /* The COMPONENT was a friend, not a member, and so there's 2611 nothing for us to do. */ 2612 return; 2613 2614 /* We should see only one DECL at a time. */ 2615 gcc_assert (DECL_CHAIN (decl) == NULL_TREE); 2616 2617 /* Set up access control for DECL. */ 2618 TREE_PRIVATE (decl) 2619 = (current_access_specifier == access_private_node); 2620 TREE_PROTECTED (decl) 2621 = (current_access_specifier == access_protected_node); 2622 if (TREE_CODE (decl) == TEMPLATE_DECL) 2623 { 2624 TREE_PRIVATE (DECL_TEMPLATE_RESULT (decl)) = TREE_PRIVATE (decl); 2625 TREE_PROTECTED (DECL_TEMPLATE_RESULT (decl)) = TREE_PROTECTED (decl); 2626 } 2627 2628 /* Mark the DECL as a member of the current class. */ 2629 DECL_CONTEXT (decl) = current_class_type; 2630 2631 /* Check for bare parameter packs in the member variable declaration. */ 2632 if (TREE_CODE (decl) == FIELD_DECL) 2633 { 2634 if (check_for_bare_parameter_packs (TREE_TYPE (decl))) 2635 TREE_TYPE (decl) = error_mark_node; 2636 if (check_for_bare_parameter_packs (DECL_ATTRIBUTES (decl))) 2637 DECL_ATTRIBUTES (decl) = NULL_TREE; 2638 } 2639 2640 /* [dcl.link] 2641 2642 A C language linkage is ignored for the names of class members 2643 and the member function type of class member functions. */ 2644 if (DECL_LANG_SPECIFIC (decl) && DECL_LANGUAGE (decl) == lang_c) 2645 SET_DECL_LANGUAGE (decl, lang_cplusplus); 2646 2647 /* Put functions on the TYPE_METHODS list and everything else on the 2648 TYPE_FIELDS list. Note that these are built up in reverse order. 2649 We reverse them (to obtain declaration order) in finish_struct. */ 2650 if (TREE_CODE (decl) == FUNCTION_DECL 2651 || DECL_FUNCTION_TEMPLATE_P (decl)) 2652 { 2653 /* We also need to add this function to the 2654 CLASSTYPE_METHOD_VEC. */ 2655 if (add_method (current_class_type, decl, NULL_TREE)) 2656 { 2657 DECL_CHAIN (decl) = TYPE_METHODS (current_class_type); 2658 TYPE_METHODS (current_class_type) = decl; 2659 2660 maybe_add_class_template_decl_list (current_class_type, decl, 2661 /*friend_p=*/0); 2662 } 2663 } 2664 /* Enter the DECL into the scope of the class. */ 2665 else if (pushdecl_class_level (decl)) 2666 { 2667 if (TREE_CODE (decl) == USING_DECL) 2668 { 2669 /* For now, ignore class-scope USING_DECLS, so that 2670 debugging backends do not see them. */ 2671 DECL_IGNORED_P (decl) = 1; 2672 } 2673 2674 /* All TYPE_DECLs go at the end of TYPE_FIELDS. Ordinary fields 2675 go at the beginning. The reason is that lookup_field_1 2676 searches the list in order, and we want a field name to 2677 override a type name so that the "struct stat hack" will 2678 work. In particular: 2679 2680 struct S { enum E { }; int E } s; 2681 s.E = 3; 2682 2683 is valid. In addition, the FIELD_DECLs must be maintained in 2684 declaration order so that class layout works as expected. 2685 However, we don't need that order until class layout, so we 2686 save a little time by putting FIELD_DECLs on in reverse order 2687 here, and then reversing them in finish_struct_1. (We could 2688 also keep a pointer to the correct insertion points in the 2689 list.) */ 2690 2691 if (TREE_CODE (decl) == TYPE_DECL) 2692 TYPE_FIELDS (current_class_type) 2693 = chainon (TYPE_FIELDS (current_class_type), decl); 2694 else 2695 { 2696 DECL_CHAIN (decl) = TYPE_FIELDS (current_class_type); 2697 TYPE_FIELDS (current_class_type) = decl; 2698 } 2699 2700 maybe_add_class_template_decl_list (current_class_type, decl, 2701 /*friend_p=*/0); 2702 } 2703 2704 if (pch_file) 2705 note_decl_for_pch (decl); 2706 } 2707 2708 /* DECL has been declared while we are building a PCH file. Perform 2709 actions that we might normally undertake lazily, but which can be 2710 performed now so that they do not have to be performed in 2711 translation units which include the PCH file. */ 2712 2713 void 2714 note_decl_for_pch (tree decl) 2715 { 2716 gcc_assert (pch_file); 2717 2718 /* There's a good chance that we'll have to mangle names at some 2719 point, even if only for emission in debugging information. */ 2720 if ((TREE_CODE (decl) == VAR_DECL 2721 || TREE_CODE (decl) == FUNCTION_DECL) 2722 && !processing_template_decl) 2723 mangle_decl (decl); 2724 } 2725 2726 /* Finish processing a complete template declaration. The PARMS are 2727 the template parameters. */ 2728 2729 void 2730 finish_template_decl (tree parms) 2731 { 2732 if (parms) 2733 end_template_decl (); 2734 else 2735 end_specialization (); 2736 } 2737 2738 /* Finish processing a template-id (which names a type) of the form 2739 NAME < ARGS >. Return the TYPE_DECL for the type named by the 2740 template-id. If ENTERING_SCOPE is nonzero we are about to enter 2741 the scope of template-id indicated. */ 2742 2743 tree 2744 finish_template_type (tree name, tree args, int entering_scope) 2745 { 2746 tree type; 2747 2748 type = lookup_template_class (name, args, 2749 NULL_TREE, NULL_TREE, entering_scope, 2750 tf_warning_or_error | tf_user); 2751 if (type == error_mark_node) 2752 return type; 2753 else if (CLASS_TYPE_P (type) && !alias_type_or_template_p (type)) 2754 return TYPE_STUB_DECL (type); 2755 else 2756 return TYPE_NAME (type); 2757 } 2758 2759 /* Finish processing a BASE_CLASS with the indicated ACCESS_SPECIFIER. 2760 Return a TREE_LIST containing the ACCESS_SPECIFIER and the 2761 BASE_CLASS, or NULL_TREE if an error occurred. The 2762 ACCESS_SPECIFIER is one of 2763 access_{default,public,protected_private}_node. For a virtual base 2764 we set TREE_TYPE. */ 2765 2766 tree 2767 finish_base_specifier (tree base, tree access, bool virtual_p) 2768 { 2769 tree result; 2770 2771 if (base == error_mark_node) 2772 { 2773 error ("invalid base-class specification"); 2774 result = NULL_TREE; 2775 } 2776 else if (! MAYBE_CLASS_TYPE_P (base)) 2777 { 2778 error ("%qT is not a class type", base); 2779 result = NULL_TREE; 2780 } 2781 else 2782 { 2783 if (cp_type_quals (base) != 0) 2784 { 2785 /* DR 484: Can a base-specifier name a cv-qualified 2786 class type? */ 2787 base = TYPE_MAIN_VARIANT (base); 2788 } 2789 result = build_tree_list (access, base); 2790 if (virtual_p) 2791 TREE_TYPE (result) = integer_type_node; 2792 } 2793 2794 return result; 2795 } 2796 2797 /* If FNS is a member function, a set of member functions, or a 2798 template-id referring to one or more member functions, return a 2799 BASELINK for FNS, incorporating the current access context. 2800 Otherwise, return FNS unchanged. */ 2801 2802 tree 2803 baselink_for_fns (tree fns) 2804 { 2805 tree scope; 2806 tree cl; 2807 2808 if (BASELINK_P (fns) 2809 || error_operand_p (fns)) 2810 return fns; 2811 2812 scope = ovl_scope (fns); 2813 if (!CLASS_TYPE_P (scope)) 2814 return fns; 2815 2816 cl = currently_open_derived_class (scope); 2817 if (!cl) 2818 cl = scope; 2819 cl = TYPE_BINFO (cl); 2820 return build_baselink (cl, cl, fns, /*optype=*/NULL_TREE); 2821 } 2822 2823 /* Returns true iff DECL is a variable from a function outside 2824 the current one. */ 2825 2826 static bool 2827 outer_var_p (tree decl) 2828 { 2829 return ((TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == PARM_DECL) 2830 && DECL_FUNCTION_SCOPE_P (decl) 2831 && DECL_CONTEXT (decl) != current_function_decl); 2832 } 2833 2834 /* As above, but also checks that DECL is automatic. */ 2835 2836 static bool 2837 outer_automatic_var_p (tree decl) 2838 { 2839 return (outer_var_p (decl) 2840 && !TREE_STATIC (decl)); 2841 } 2842 2843 /* ID_EXPRESSION is a representation of parsed, but unprocessed, 2844 id-expression. (See cp_parser_id_expression for details.) SCOPE, 2845 if non-NULL, is the type or namespace used to explicitly qualify 2846 ID_EXPRESSION. DECL is the entity to which that name has been 2847 resolved. 2848 2849 *CONSTANT_EXPRESSION_P is true if we are presently parsing a 2850 constant-expression. In that case, *NON_CONSTANT_EXPRESSION_P will 2851 be set to true if this expression isn't permitted in a 2852 constant-expression, but it is otherwise not set by this function. 2853 *ALLOW_NON_CONSTANT_EXPRESSION_P is true if we are parsing a 2854 constant-expression, but a non-constant expression is also 2855 permissible. 2856 2857 DONE is true if this expression is a complete postfix-expression; 2858 it is false if this expression is followed by '->', '[', '(', etc. 2859 ADDRESS_P is true iff this expression is the operand of '&'. 2860 TEMPLATE_P is true iff the qualified-id was of the form 2861 "A::template B". TEMPLATE_ARG_P is true iff this qualified name 2862 appears as a template argument. 2863 2864 If an error occurs, and it is the kind of error that might cause 2865 the parser to abort a tentative parse, *ERROR_MSG is filled in. It 2866 is the caller's responsibility to issue the message. *ERROR_MSG 2867 will be a string with static storage duration, so the caller need 2868 not "free" it. 2869 2870 Return an expression for the entity, after issuing appropriate 2871 diagnostics. This function is also responsible for transforming a 2872 reference to a non-static member into a COMPONENT_REF that makes 2873 the use of "this" explicit. 2874 2875 Upon return, *IDK will be filled in appropriately. */ 2876 tree 2877 finish_id_expression (tree id_expression, 2878 tree decl, 2879 tree scope, 2880 cp_id_kind *idk, 2881 bool integral_constant_expression_p, 2882 bool allow_non_integral_constant_expression_p, 2883 bool *non_integral_constant_expression_p, 2884 bool template_p, 2885 bool done, 2886 bool address_p, 2887 bool template_arg_p, 2888 const char **error_msg, 2889 location_t location) 2890 { 2891 decl = strip_using_decl (decl); 2892 2893 /* Initialize the output parameters. */ 2894 *idk = CP_ID_KIND_NONE; 2895 *error_msg = NULL; 2896 2897 if (id_expression == error_mark_node) 2898 return error_mark_node; 2899 /* If we have a template-id, then no further lookup is 2900 required. If the template-id was for a template-class, we 2901 will sometimes have a TYPE_DECL at this point. */ 2902 else if (TREE_CODE (decl) == TEMPLATE_ID_EXPR 2903 || TREE_CODE (decl) == TYPE_DECL) 2904 ; 2905 /* Look up the name. */ 2906 else 2907 { 2908 if (decl == error_mark_node) 2909 { 2910 /* Name lookup failed. */ 2911 if (scope 2912 && (!TYPE_P (scope) 2913 || (!dependent_type_p (scope) 2914 && !(TREE_CODE (id_expression) == IDENTIFIER_NODE 2915 && IDENTIFIER_TYPENAME_P (id_expression) 2916 && dependent_type_p (TREE_TYPE (id_expression)))))) 2917 { 2918 /* If the qualifying type is non-dependent (and the name 2919 does not name a conversion operator to a dependent 2920 type), issue an error. */ 2921 qualified_name_lookup_error (scope, id_expression, decl, location); 2922 return error_mark_node; 2923 } 2924 else if (!scope) 2925 { 2926 /* It may be resolved via Koenig lookup. */ 2927 *idk = CP_ID_KIND_UNQUALIFIED; 2928 return id_expression; 2929 } 2930 else 2931 decl = id_expression; 2932 } 2933 /* If DECL is a variable that would be out of scope under 2934 ANSI/ISO rules, but in scope in the ARM, name lookup 2935 will succeed. Issue a diagnostic here. */ 2936 else 2937 decl = check_for_out_of_scope_variable (decl); 2938 2939 /* Remember that the name was used in the definition of 2940 the current class so that we can check later to see if 2941 the meaning would have been different after the class 2942 was entirely defined. */ 2943 if (!scope && decl != error_mark_node 2944 && TREE_CODE (id_expression) == IDENTIFIER_NODE) 2945 maybe_note_name_used_in_class (id_expression, decl); 2946 2947 /* Disallow uses of local variables from containing functions, except 2948 within lambda-expressions. */ 2949 if (!outer_var_p (decl) 2950 /* It's not a use (3.2) if we're in an unevaluated context. */ 2951 || cp_unevaluated_operand) 2952 /* OK. */; 2953 else if (TREE_STATIC (decl)) 2954 { 2955 if (processing_template_decl) 2956 /* For a use of an outer static var, return the identifier so 2957 that we'll look it up again in the instantiation. */ 2958 return id_expression; 2959 } 2960 else 2961 { 2962 tree context = DECL_CONTEXT (decl); 2963 tree containing_function = current_function_decl; 2964 tree lambda_stack = NULL_TREE; 2965 tree lambda_expr = NULL_TREE; 2966 tree initializer = convert_from_reference (decl); 2967 2968 /* Mark it as used now even if the use is ill-formed. */ 2969 mark_used (decl); 2970 2971 /* Core issue 696: "[At the July 2009 meeting] the CWG expressed 2972 support for an approach in which a reference to a local 2973 [constant] automatic variable in a nested class or lambda body 2974 would enter the expression as an rvalue, which would reduce 2975 the complexity of the problem" 2976 2977 FIXME update for final resolution of core issue 696. */ 2978 if (decl_constant_var_p (decl)) 2979 { 2980 if (processing_template_decl) 2981 /* In a template, the constant value may not be in a usable 2982 form, so look it up again at instantiation time. */ 2983 return id_expression; 2984 else 2985 return integral_constant_value (decl); 2986 } 2987 2988 /* If we are in a lambda function, we can move out until we hit 2989 1. the context, 2990 2. a non-lambda function, or 2991 3. a non-default capturing lambda function. */ 2992 while (context != containing_function 2993 && LAMBDA_FUNCTION_P (containing_function)) 2994 { 2995 lambda_expr = CLASSTYPE_LAMBDA_EXPR 2996 (DECL_CONTEXT (containing_function)); 2997 2998 if (LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda_expr) 2999 == CPLD_NONE) 3000 break; 3001 3002 lambda_stack = tree_cons (NULL_TREE, 3003 lambda_expr, 3004 lambda_stack); 3005 3006 containing_function 3007 = decl_function_context (containing_function); 3008 } 3009 3010 if (context == containing_function) 3011 { 3012 decl = add_default_capture (lambda_stack, 3013 /*id=*/DECL_NAME (decl), 3014 initializer); 3015 } 3016 else if (lambda_expr) 3017 { 3018 error ("%qD is not captured", decl); 3019 return error_mark_node; 3020 } 3021 else 3022 { 3023 error (TREE_CODE (decl) == VAR_DECL 3024 ? G_("use of %<auto%> variable from containing function") 3025 : G_("use of parameter from containing function")); 3026 error (" %q+#D declared here", decl); 3027 return error_mark_node; 3028 } 3029 } 3030 3031 /* Also disallow uses of function parameters outside the function 3032 body, except inside an unevaluated context (i.e. decltype). */ 3033 if (TREE_CODE (decl) == PARM_DECL 3034 && DECL_CONTEXT (decl) == NULL_TREE 3035 && !cp_unevaluated_operand) 3036 { 3037 error ("use of parameter %qD outside function body", decl); 3038 return error_mark_node; 3039 } 3040 } 3041 3042 /* If we didn't find anything, or what we found was a type, 3043 then this wasn't really an id-expression. */ 3044 if (TREE_CODE (decl) == TEMPLATE_DECL 3045 && !DECL_FUNCTION_TEMPLATE_P (decl)) 3046 { 3047 *error_msg = "missing template arguments"; 3048 return error_mark_node; 3049 } 3050 else if (TREE_CODE (decl) == TYPE_DECL 3051 || TREE_CODE (decl) == NAMESPACE_DECL) 3052 { 3053 *error_msg = "expected primary-expression"; 3054 return error_mark_node; 3055 } 3056 3057 /* If the name resolved to a template parameter, there is no 3058 need to look it up again later. */ 3059 if ((TREE_CODE (decl) == CONST_DECL && DECL_TEMPLATE_PARM_P (decl)) 3060 || TREE_CODE (decl) == TEMPLATE_PARM_INDEX) 3061 { 3062 tree r; 3063 3064 *idk = CP_ID_KIND_NONE; 3065 if (TREE_CODE (decl) == TEMPLATE_PARM_INDEX) 3066 decl = TEMPLATE_PARM_DECL (decl); 3067 r = convert_from_reference (DECL_INITIAL (decl)); 3068 3069 if (integral_constant_expression_p 3070 && !dependent_type_p (TREE_TYPE (decl)) 3071 && !(INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (r)))) 3072 { 3073 if (!allow_non_integral_constant_expression_p) 3074 error ("template parameter %qD of type %qT is not allowed in " 3075 "an integral constant expression because it is not of " 3076 "integral or enumeration type", decl, TREE_TYPE (decl)); 3077 *non_integral_constant_expression_p = true; 3078 } 3079 return r; 3080 } 3081 /* Similarly, we resolve enumeration constants to their 3082 underlying values. */ 3083 else if (TREE_CODE (decl) == CONST_DECL) 3084 { 3085 *idk = CP_ID_KIND_NONE; 3086 if (!processing_template_decl) 3087 { 3088 used_types_insert (TREE_TYPE (decl)); 3089 return DECL_INITIAL (decl); 3090 } 3091 return decl; 3092 } 3093 else 3094 { 3095 bool dependent_p; 3096 3097 /* If the declaration was explicitly qualified indicate 3098 that. The semantics of `A::f(3)' are different than 3099 `f(3)' if `f' is virtual. */ 3100 *idk = (scope 3101 ? CP_ID_KIND_QUALIFIED 3102 : (TREE_CODE (decl) == TEMPLATE_ID_EXPR 3103 ? CP_ID_KIND_TEMPLATE_ID 3104 : CP_ID_KIND_UNQUALIFIED)); 3105 3106 3107 /* [temp.dep.expr] 3108 3109 An id-expression is type-dependent if it contains an 3110 identifier that was declared with a dependent type. 3111 3112 The standard is not very specific about an id-expression that 3113 names a set of overloaded functions. What if some of them 3114 have dependent types and some of them do not? Presumably, 3115 such a name should be treated as a dependent name. */ 3116 /* Assume the name is not dependent. */ 3117 dependent_p = false; 3118 if (!processing_template_decl) 3119 /* No names are dependent outside a template. */ 3120 ; 3121 /* A template-id where the name of the template was not resolved 3122 is definitely dependent. */ 3123 else if (TREE_CODE (decl) == TEMPLATE_ID_EXPR 3124 && (TREE_CODE (TREE_OPERAND (decl, 0)) 3125 == IDENTIFIER_NODE)) 3126 dependent_p = true; 3127 /* For anything except an overloaded function, just check its 3128 type. */ 3129 else if (!is_overloaded_fn (decl)) 3130 dependent_p 3131 = dependent_type_p (TREE_TYPE (decl)); 3132 /* For a set of overloaded functions, check each of the 3133 functions. */ 3134 else 3135 { 3136 tree fns = decl; 3137 3138 if (BASELINK_P (fns)) 3139 fns = BASELINK_FUNCTIONS (fns); 3140 3141 /* For a template-id, check to see if the template 3142 arguments are dependent. */ 3143 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR) 3144 { 3145 tree args = TREE_OPERAND (fns, 1); 3146 dependent_p = any_dependent_template_arguments_p (args); 3147 /* The functions are those referred to by the 3148 template-id. */ 3149 fns = TREE_OPERAND (fns, 0); 3150 } 3151 3152 /* If there are no dependent template arguments, go through 3153 the overloaded functions. */ 3154 while (fns && !dependent_p) 3155 { 3156 tree fn = OVL_CURRENT (fns); 3157 3158 /* Member functions of dependent classes are 3159 dependent. */ 3160 if (TREE_CODE (fn) == FUNCTION_DECL 3161 && type_dependent_expression_p (fn)) 3162 dependent_p = true; 3163 else if (TREE_CODE (fn) == TEMPLATE_DECL 3164 && dependent_template_p (fn)) 3165 dependent_p = true; 3166 3167 fns = OVL_NEXT (fns); 3168 } 3169 } 3170 3171 /* If the name was dependent on a template parameter, we will 3172 resolve the name at instantiation time. */ 3173 if (dependent_p) 3174 { 3175 /* Create a SCOPE_REF for qualified names, if the scope is 3176 dependent. */ 3177 if (scope) 3178 { 3179 if (TYPE_P (scope)) 3180 { 3181 if (address_p && done) 3182 decl = finish_qualified_id_expr (scope, decl, 3183 done, address_p, 3184 template_p, 3185 template_arg_p); 3186 else 3187 { 3188 tree type = NULL_TREE; 3189 if (DECL_P (decl) && !dependent_scope_p (scope)) 3190 type = TREE_TYPE (decl); 3191 decl = build_qualified_name (type, 3192 scope, 3193 id_expression, 3194 template_p); 3195 } 3196 } 3197 if (TREE_TYPE (decl)) 3198 decl = convert_from_reference (decl); 3199 return decl; 3200 } 3201 /* A TEMPLATE_ID already contains all the information we 3202 need. */ 3203 if (TREE_CODE (id_expression) == TEMPLATE_ID_EXPR) 3204 return id_expression; 3205 *idk = CP_ID_KIND_UNQUALIFIED_DEPENDENT; 3206 /* If we found a variable, then name lookup during the 3207 instantiation will always resolve to the same VAR_DECL 3208 (or an instantiation thereof). */ 3209 if (TREE_CODE (decl) == VAR_DECL 3210 || TREE_CODE (decl) == PARM_DECL) 3211 { 3212 mark_used (decl); 3213 return convert_from_reference (decl); 3214 } 3215 /* The same is true for FIELD_DECL, but we also need to 3216 make sure that the syntax is correct. */ 3217 else if (TREE_CODE (decl) == FIELD_DECL) 3218 { 3219 /* Since SCOPE is NULL here, this is an unqualified name. 3220 Access checking has been performed during name lookup 3221 already. Turn off checking to avoid duplicate errors. */ 3222 push_deferring_access_checks (dk_no_check); 3223 decl = finish_non_static_data_member 3224 (decl, NULL_TREE, 3225 /*qualifying_scope=*/NULL_TREE); 3226 pop_deferring_access_checks (); 3227 return decl; 3228 } 3229 return id_expression; 3230 } 3231 3232 if (TREE_CODE (decl) == NAMESPACE_DECL) 3233 { 3234 error ("use of namespace %qD as expression", decl); 3235 return error_mark_node; 3236 } 3237 else if (DECL_CLASS_TEMPLATE_P (decl)) 3238 { 3239 error ("use of class template %qT as expression", decl); 3240 return error_mark_node; 3241 } 3242 else if (TREE_CODE (decl) == TREE_LIST) 3243 { 3244 /* Ambiguous reference to base members. */ 3245 error ("request for member %qD is ambiguous in " 3246 "multiple inheritance lattice", id_expression); 3247 print_candidates (decl); 3248 return error_mark_node; 3249 } 3250 3251 /* Mark variable-like entities as used. Functions are similarly 3252 marked either below or after overload resolution. */ 3253 if (TREE_CODE (decl) == VAR_DECL 3254 || TREE_CODE (decl) == PARM_DECL 3255 || TREE_CODE (decl) == RESULT_DECL) 3256 mark_used (decl); 3257 3258 /* Only certain kinds of names are allowed in constant 3259 expression. Enumerators and template parameters have already 3260 been handled above. */ 3261 if (! error_operand_p (decl) 3262 && integral_constant_expression_p 3263 && ! decl_constant_var_p (decl) 3264 && ! builtin_valid_in_constant_expr_p (decl)) 3265 { 3266 if (!allow_non_integral_constant_expression_p) 3267 { 3268 error ("%qD cannot appear in a constant-expression", decl); 3269 return error_mark_node; 3270 } 3271 *non_integral_constant_expression_p = true; 3272 } 3273 3274 if (scope) 3275 { 3276 decl = (adjust_result_of_qualified_name_lookup 3277 (decl, scope, current_nonlambda_class_type())); 3278 3279 if (TREE_CODE (decl) == FUNCTION_DECL) 3280 mark_used (decl); 3281 3282 if (TREE_CODE (decl) == FIELD_DECL || BASELINK_P (decl)) 3283 decl = finish_qualified_id_expr (scope, 3284 decl, 3285 done, 3286 address_p, 3287 template_p, 3288 template_arg_p); 3289 else 3290 { 3291 tree r = convert_from_reference (decl); 3292 3293 /* In a template, return a SCOPE_REF for most qualified-ids 3294 so that we can check access at instantiation time. But if 3295 we're looking at a member of the current instantiation, we 3296 know we have access and building up the SCOPE_REF confuses 3297 non-type template argument handling. */ 3298 if (processing_template_decl && TYPE_P (scope) 3299 && !currently_open_class (scope)) 3300 r = build_qualified_name (TREE_TYPE (r), 3301 scope, decl, 3302 template_p); 3303 decl = r; 3304 } 3305 } 3306 else if (TREE_CODE (decl) == FIELD_DECL) 3307 { 3308 /* Since SCOPE is NULL here, this is an unqualified name. 3309 Access checking has been performed during name lookup 3310 already. Turn off checking to avoid duplicate errors. */ 3311 push_deferring_access_checks (dk_no_check); 3312 decl = finish_non_static_data_member (decl, NULL_TREE, 3313 /*qualifying_scope=*/NULL_TREE); 3314 pop_deferring_access_checks (); 3315 } 3316 else if (is_overloaded_fn (decl)) 3317 { 3318 tree first_fn; 3319 3320 first_fn = get_first_fn (decl); 3321 if (TREE_CODE (first_fn) == TEMPLATE_DECL) 3322 first_fn = DECL_TEMPLATE_RESULT (first_fn); 3323 3324 if (!really_overloaded_fn (decl) 3325 && !mark_used (first_fn)) 3326 return error_mark_node; 3327 3328 if (!template_arg_p 3329 && TREE_CODE (first_fn) == FUNCTION_DECL 3330 && DECL_FUNCTION_MEMBER_P (first_fn) 3331 && !shared_member_p (decl)) 3332 { 3333 /* A set of member functions. */ 3334 decl = maybe_dummy_object (DECL_CONTEXT (first_fn), 0); 3335 return finish_class_member_access_expr (decl, id_expression, 3336 /*template_p=*/false, 3337 tf_warning_or_error); 3338 } 3339 3340 decl = baselink_for_fns (decl); 3341 } 3342 else 3343 { 3344 if (DECL_P (decl) && DECL_NONLOCAL (decl) 3345 && DECL_CLASS_SCOPE_P (decl)) 3346 { 3347 tree context = context_for_name_lookup (decl); 3348 if (context != current_class_type) 3349 { 3350 tree path = currently_open_derived_class (context); 3351 perform_or_defer_access_check (TYPE_BINFO (path), 3352 decl, decl); 3353 } 3354 } 3355 3356 decl = convert_from_reference (decl); 3357 } 3358 } 3359 3360 if (TREE_DEPRECATED (decl)) 3361 warn_deprecated_use (decl, NULL_TREE); 3362 3363 return decl; 3364 } 3365 3366 /* Implement the __typeof keyword: Return the type of EXPR, suitable for 3367 use as a type-specifier. */ 3368 3369 tree 3370 finish_typeof (tree expr) 3371 { 3372 tree type; 3373 3374 if (type_dependent_expression_p (expr)) 3375 { 3376 type = cxx_make_type (TYPEOF_TYPE); 3377 TYPEOF_TYPE_EXPR (type) = expr; 3378 SET_TYPE_STRUCTURAL_EQUALITY (type); 3379 3380 return type; 3381 } 3382 3383 expr = mark_type_use (expr); 3384 3385 type = unlowered_expr_type (expr); 3386 3387 if (!type || type == unknown_type_node) 3388 { 3389 error ("type of %qE is unknown", expr); 3390 return error_mark_node; 3391 } 3392 3393 return type; 3394 } 3395 3396 /* Implement the __underlying_type keyword: Return the underlying 3397 type of TYPE, suitable for use as a type-specifier. */ 3398 3399 tree 3400 finish_underlying_type (tree type) 3401 { 3402 tree underlying_type; 3403 3404 if (processing_template_decl) 3405 { 3406 underlying_type = cxx_make_type (UNDERLYING_TYPE); 3407 UNDERLYING_TYPE_TYPE (underlying_type) = type; 3408 SET_TYPE_STRUCTURAL_EQUALITY (underlying_type); 3409 3410 return underlying_type; 3411 } 3412 3413 complete_type (type); 3414 3415 if (TREE_CODE (type) != ENUMERAL_TYPE) 3416 { 3417 error ("%qT is not an enumeration type", type); 3418 return error_mark_node; 3419 } 3420 3421 underlying_type = ENUM_UNDERLYING_TYPE (type); 3422 3423 /* Fixup necessary in this case because ENUM_UNDERLYING_TYPE 3424 includes TYPE_MIN_VALUE and TYPE_MAX_VALUE information. 3425 See finish_enum_value_list for details. */ 3426 if (!ENUM_FIXED_UNDERLYING_TYPE_P (type)) 3427 underlying_type 3428 = c_common_type_for_mode (TYPE_MODE (underlying_type), 3429 TYPE_UNSIGNED (underlying_type)); 3430 3431 return underlying_type; 3432 } 3433 3434 /* Implement the __direct_bases keyword: Return the direct base classes 3435 of type */ 3436 3437 tree 3438 calculate_direct_bases (tree type) 3439 { 3440 VEC(tree, gc) *vector = make_tree_vector(); 3441 tree bases_vec = NULL_TREE; 3442 VEC(tree, none) *base_binfos; 3443 tree binfo; 3444 unsigned i; 3445 3446 complete_type (type); 3447 3448 if (!NON_UNION_CLASS_TYPE_P (type)) 3449 return make_tree_vec (0); 3450 3451 base_binfos = BINFO_BASE_BINFOS (TYPE_BINFO (type)); 3452 3453 /* Virtual bases are initialized first */ 3454 for (i = 0; VEC_iterate (tree, base_binfos, i, binfo); i++) 3455 { 3456 if (BINFO_VIRTUAL_P (binfo)) 3457 { 3458 VEC_safe_push (tree, gc, vector, binfo); 3459 } 3460 } 3461 3462 /* Now non-virtuals */ 3463 for (i = 0; VEC_iterate (tree, base_binfos, i, binfo); i++) 3464 { 3465 if (!BINFO_VIRTUAL_P (binfo)) 3466 { 3467 VEC_safe_push (tree, gc, vector, binfo); 3468 } 3469 } 3470 3471 3472 bases_vec = make_tree_vec (VEC_length (tree, vector)); 3473 3474 for (i = 0; i < VEC_length (tree, vector); ++i) 3475 { 3476 TREE_VEC_ELT (bases_vec, i) = BINFO_TYPE (VEC_index (tree, vector, i)); 3477 } 3478 return bases_vec; 3479 } 3480 3481 /* Implement the __bases keyword: Return the base classes 3482 of type */ 3483 3484 /* Find morally non-virtual base classes by walking binfo hierarchy */ 3485 /* Virtual base classes are handled separately in finish_bases */ 3486 3487 static tree 3488 dfs_calculate_bases_pre (tree binfo, ATTRIBUTE_UNUSED void *data_) 3489 { 3490 /* Don't walk bases of virtual bases */ 3491 return BINFO_VIRTUAL_P (binfo) ? dfs_skip_bases : NULL_TREE; 3492 } 3493 3494 static tree 3495 dfs_calculate_bases_post (tree binfo, void *data_) 3496 { 3497 VEC(tree, gc) **data = (VEC(tree, gc) **) data_; 3498 if (!BINFO_VIRTUAL_P (binfo)) 3499 { 3500 VEC_safe_push (tree, gc, *data, BINFO_TYPE (binfo)); 3501 } 3502 return NULL_TREE; 3503 } 3504 3505 /* Calculates the morally non-virtual base classes of a class */ 3506 static VEC(tree, gc) * 3507 calculate_bases_helper (tree type) 3508 { 3509 VEC(tree, gc) *vector = make_tree_vector(); 3510 3511 /* Now add non-virtual base classes in order of construction */ 3512 dfs_walk_all (TYPE_BINFO (type), 3513 dfs_calculate_bases_pre, dfs_calculate_bases_post, &vector); 3514 return vector; 3515 } 3516 3517 tree 3518 calculate_bases (tree type) 3519 { 3520 VEC(tree, gc) *vector = make_tree_vector(); 3521 tree bases_vec = NULL_TREE; 3522 unsigned i; 3523 VEC(tree, gc) *vbases; 3524 VEC(tree, gc) *nonvbases; 3525 tree binfo; 3526 3527 complete_type (type); 3528 3529 if (!NON_UNION_CLASS_TYPE_P (type)) 3530 return make_tree_vec (0); 3531 3532 /* First go through virtual base classes */ 3533 for (vbases = CLASSTYPE_VBASECLASSES (type), i = 0; 3534 VEC_iterate (tree, vbases, i, binfo); i++) 3535 { 3536 VEC(tree, gc) *vbase_bases = calculate_bases_helper (BINFO_TYPE (binfo)); 3537 VEC_safe_splice (tree, gc, vector, vbase_bases); 3538 release_tree_vector (vbase_bases); 3539 } 3540 3541 /* Now for the non-virtual bases */ 3542 nonvbases = calculate_bases_helper (type); 3543 VEC_safe_splice (tree, gc, vector, nonvbases); 3544 release_tree_vector (nonvbases); 3545 3546 /* Last element is entire class, so don't copy */ 3547 bases_vec = make_tree_vec (VEC_length (tree, vector) - 1); 3548 3549 for (i = 0; i < VEC_length (tree, vector) - 1; ++i) 3550 { 3551 TREE_VEC_ELT (bases_vec, i) = VEC_index (tree, vector, i); 3552 } 3553 release_tree_vector (vector); 3554 return bases_vec; 3555 } 3556 3557 tree 3558 finish_bases (tree type, bool direct) 3559 { 3560 tree bases = NULL_TREE; 3561 3562 if (!processing_template_decl) 3563 { 3564 /* Parameter packs can only be used in templates */ 3565 error ("Parameter pack __bases only valid in template declaration"); 3566 return error_mark_node; 3567 } 3568 3569 bases = cxx_make_type (BASES); 3570 BASES_TYPE (bases) = type; 3571 BASES_DIRECT (bases) = direct; 3572 SET_TYPE_STRUCTURAL_EQUALITY (bases); 3573 3574 return bases; 3575 } 3576 3577 /* Perform C++-specific checks for __builtin_offsetof before calling 3578 fold_offsetof. */ 3579 3580 tree 3581 finish_offsetof (tree expr) 3582 { 3583 if (TREE_CODE (expr) == PSEUDO_DTOR_EXPR) 3584 { 3585 error ("cannot apply %<offsetof%> to destructor %<~%T%>", 3586 TREE_OPERAND (expr, 2)); 3587 return error_mark_node; 3588 } 3589 if (TREE_CODE (TREE_TYPE (expr)) == FUNCTION_TYPE 3590 || TREE_CODE (TREE_TYPE (expr)) == METHOD_TYPE 3591 || TREE_TYPE (expr) == unknown_type_node) 3592 { 3593 if (TREE_CODE (expr) == COMPONENT_REF 3594 || TREE_CODE (expr) == COMPOUND_EXPR) 3595 expr = TREE_OPERAND (expr, 1); 3596 error ("cannot apply %<offsetof%> to member function %qD", expr); 3597 return error_mark_node; 3598 } 3599 if (REFERENCE_REF_P (expr)) 3600 expr = TREE_OPERAND (expr, 0); 3601 if (TREE_CODE (expr) == COMPONENT_REF) 3602 { 3603 tree object = TREE_OPERAND (expr, 0); 3604 if (!complete_type_or_else (TREE_TYPE (object), object)) 3605 return error_mark_node; 3606 } 3607 return fold_offsetof (expr); 3608 } 3609 3610 /* Replace the AGGR_INIT_EXPR at *TP with an equivalent CALL_EXPR. This 3611 function is broken out from the above for the benefit of the tree-ssa 3612 project. */ 3613 3614 void 3615 simplify_aggr_init_expr (tree *tp) 3616 { 3617 tree aggr_init_expr = *tp; 3618 3619 /* Form an appropriate CALL_EXPR. */ 3620 tree fn = AGGR_INIT_EXPR_FN (aggr_init_expr); 3621 tree slot = AGGR_INIT_EXPR_SLOT (aggr_init_expr); 3622 tree type = TREE_TYPE (slot); 3623 3624 tree call_expr; 3625 enum style_t { ctor, arg, pcc } style; 3626 3627 if (AGGR_INIT_VIA_CTOR_P (aggr_init_expr)) 3628 style = ctor; 3629 #ifdef PCC_STATIC_STRUCT_RETURN 3630 else if (1) 3631 style = pcc; 3632 #endif 3633 else 3634 { 3635 gcc_assert (TREE_ADDRESSABLE (type)); 3636 style = arg; 3637 } 3638 3639 call_expr = build_call_array_loc (input_location, 3640 TREE_TYPE (TREE_TYPE (TREE_TYPE (fn))), 3641 fn, 3642 aggr_init_expr_nargs (aggr_init_expr), 3643 AGGR_INIT_EXPR_ARGP (aggr_init_expr)); 3644 TREE_NOTHROW (call_expr) = TREE_NOTHROW (aggr_init_expr); 3645 3646 if (style == ctor) 3647 { 3648 /* Replace the first argument to the ctor with the address of the 3649 slot. */ 3650 cxx_mark_addressable (slot); 3651 CALL_EXPR_ARG (call_expr, 0) = 3652 build1 (ADDR_EXPR, build_pointer_type (type), slot); 3653 } 3654 else if (style == arg) 3655 { 3656 /* Just mark it addressable here, and leave the rest to 3657 expand_call{,_inline}. */ 3658 cxx_mark_addressable (slot); 3659 CALL_EXPR_RETURN_SLOT_OPT (call_expr) = true; 3660 call_expr = build2 (INIT_EXPR, TREE_TYPE (call_expr), slot, call_expr); 3661 } 3662 else if (style == pcc) 3663 { 3664 /* If we're using the non-reentrant PCC calling convention, then we 3665 need to copy the returned value out of the static buffer into the 3666 SLOT. */ 3667 push_deferring_access_checks (dk_no_check); 3668 call_expr = build_aggr_init (slot, call_expr, 3669 DIRECT_BIND | LOOKUP_ONLYCONVERTING, 3670 tf_warning_or_error); 3671 pop_deferring_access_checks (); 3672 call_expr = build2 (COMPOUND_EXPR, TREE_TYPE (slot), call_expr, slot); 3673 } 3674 3675 if (AGGR_INIT_ZERO_FIRST (aggr_init_expr)) 3676 { 3677 tree init = build_zero_init (type, NULL_TREE, 3678 /*static_storage_p=*/false); 3679 init = build2 (INIT_EXPR, void_type_node, slot, init); 3680 call_expr = build2 (COMPOUND_EXPR, TREE_TYPE (call_expr), 3681 init, call_expr); 3682 } 3683 3684 *tp = call_expr; 3685 } 3686 3687 /* Emit all thunks to FN that should be emitted when FN is emitted. */ 3688 3689 void 3690 emit_associated_thunks (tree fn) 3691 { 3692 /* When we use vcall offsets, we emit thunks with the virtual 3693 functions to which they thunk. The whole point of vcall offsets 3694 is so that you can know statically the entire set of thunks that 3695 will ever be needed for a given virtual function, thereby 3696 enabling you to output all the thunks with the function itself. */ 3697 if (DECL_VIRTUAL_P (fn) 3698 /* Do not emit thunks for extern template instantiations. */ 3699 && ! DECL_REALLY_EXTERN (fn)) 3700 { 3701 tree thunk; 3702 3703 for (thunk = DECL_THUNKS (fn); thunk; thunk = DECL_CHAIN (thunk)) 3704 { 3705 if (!THUNK_ALIAS (thunk)) 3706 { 3707 use_thunk (thunk, /*emit_p=*/1); 3708 if (DECL_RESULT_THUNK_P (thunk)) 3709 { 3710 tree probe; 3711 3712 for (probe = DECL_THUNKS (thunk); 3713 probe; probe = DECL_CHAIN (probe)) 3714 use_thunk (probe, /*emit_p=*/1); 3715 } 3716 } 3717 else 3718 gcc_assert (!DECL_THUNKS (thunk)); 3719 } 3720 } 3721 } 3722 3723 /* Returns true iff FUN is an instantiation of a constexpr function 3724 template. */ 3725 3726 static inline bool 3727 is_instantiation_of_constexpr (tree fun) 3728 { 3729 return (DECL_TEMPLOID_INSTANTIATION (fun) 3730 && DECL_DECLARED_CONSTEXPR_P (DECL_TEMPLATE_RESULT 3731 (DECL_TI_TEMPLATE (fun)))); 3732 } 3733 3734 /* Generate RTL for FN. */ 3735 3736 bool 3737 expand_or_defer_fn_1 (tree fn) 3738 { 3739 /* When the parser calls us after finishing the body of a template 3740 function, we don't really want to expand the body. */ 3741 if (processing_template_decl) 3742 { 3743 /* Normally, collection only occurs in rest_of_compilation. So, 3744 if we don't collect here, we never collect junk generated 3745 during the processing of templates until we hit a 3746 non-template function. It's not safe to do this inside a 3747 nested class, though, as the parser may have local state that 3748 is not a GC root. */ 3749 if (!function_depth) 3750 ggc_collect (); 3751 return false; 3752 } 3753 3754 gcc_assert (DECL_SAVED_TREE (fn)); 3755 3756 /* If this is a constructor or destructor body, we have to clone 3757 it. */ 3758 if (maybe_clone_body (fn)) 3759 { 3760 /* We don't want to process FN again, so pretend we've written 3761 it out, even though we haven't. */ 3762 TREE_ASM_WRITTEN (fn) = 1; 3763 /* If this is an instantiation of a constexpr function, keep 3764 DECL_SAVED_TREE for explain_invalid_constexpr_fn. */ 3765 if (!is_instantiation_of_constexpr (fn)) 3766 DECL_SAVED_TREE (fn) = NULL_TREE; 3767 return false; 3768 } 3769 3770 /* We make a decision about linkage for these functions at the end 3771 of the compilation. Until that point, we do not want the back 3772 end to output them -- but we do want it to see the bodies of 3773 these functions so that it can inline them as appropriate. */ 3774 if (DECL_DECLARED_INLINE_P (fn) || DECL_IMPLICIT_INSTANTIATION (fn)) 3775 { 3776 if (DECL_INTERFACE_KNOWN (fn)) 3777 /* We've already made a decision as to how this function will 3778 be handled. */; 3779 else if (!at_eof) 3780 { 3781 DECL_EXTERNAL (fn) = 1; 3782 DECL_NOT_REALLY_EXTERN (fn) = 1; 3783 note_vague_linkage_fn (fn); 3784 /* A non-template inline function with external linkage will 3785 always be COMDAT. As we must eventually determine the 3786 linkage of all functions, and as that causes writes to 3787 the data mapped in from the PCH file, it's advantageous 3788 to mark the functions at this point. */ 3789 if (!DECL_IMPLICIT_INSTANTIATION (fn)) 3790 { 3791 /* This function must have external linkage, as 3792 otherwise DECL_INTERFACE_KNOWN would have been 3793 set. */ 3794 gcc_assert (TREE_PUBLIC (fn)); 3795 comdat_linkage (fn); 3796 DECL_INTERFACE_KNOWN (fn) = 1; 3797 } 3798 } 3799 else 3800 import_export_decl (fn); 3801 3802 /* If the user wants us to keep all inline functions, then mark 3803 this function as needed so that finish_file will make sure to 3804 output it later. Similarly, all dllexport'd functions must 3805 be emitted; there may be callers in other DLLs. */ 3806 if ((flag_keep_inline_functions 3807 && DECL_DECLARED_INLINE_P (fn) 3808 && !DECL_REALLY_EXTERN (fn)) 3809 || (flag_keep_inline_dllexport 3810 && lookup_attribute ("dllexport", DECL_ATTRIBUTES (fn)))) 3811 { 3812 mark_needed (fn); 3813 DECL_EXTERNAL (fn) = 0; 3814 } 3815 } 3816 3817 /* There's no reason to do any of the work here if we're only doing 3818 semantic analysis; this code just generates RTL. */ 3819 if (flag_syntax_only) 3820 return false; 3821 3822 return true; 3823 } 3824 3825 void 3826 expand_or_defer_fn (tree fn) 3827 { 3828 if (expand_or_defer_fn_1 (fn)) 3829 { 3830 function_depth++; 3831 3832 /* Expand or defer, at the whim of the compilation unit manager. */ 3833 cgraph_finalize_function (fn, function_depth > 1); 3834 emit_associated_thunks (fn); 3835 3836 function_depth--; 3837 } 3838 } 3839 3840 struct nrv_data 3841 { 3842 tree var; 3843 tree result; 3844 htab_t visited; 3845 }; 3846 3847 /* Helper function for walk_tree, used by finalize_nrv below. */ 3848 3849 static tree 3850 finalize_nrv_r (tree* tp, int* walk_subtrees, void* data) 3851 { 3852 struct nrv_data *dp = (struct nrv_data *)data; 3853 void **slot; 3854 3855 /* No need to walk into types. There wouldn't be any need to walk into 3856 non-statements, except that we have to consider STMT_EXPRs. */ 3857 if (TYPE_P (*tp)) 3858 *walk_subtrees = 0; 3859 /* Change all returns to just refer to the RESULT_DECL; this is a nop, 3860 but differs from using NULL_TREE in that it indicates that we care 3861 about the value of the RESULT_DECL. */ 3862 else if (TREE_CODE (*tp) == RETURN_EXPR) 3863 TREE_OPERAND (*tp, 0) = dp->result; 3864 /* Change all cleanups for the NRV to only run when an exception is 3865 thrown. */ 3866 else if (TREE_CODE (*tp) == CLEANUP_STMT 3867 && CLEANUP_DECL (*tp) == dp->var) 3868 CLEANUP_EH_ONLY (*tp) = 1; 3869 /* Replace the DECL_EXPR for the NRV with an initialization of the 3870 RESULT_DECL, if needed. */ 3871 else if (TREE_CODE (*tp) == DECL_EXPR 3872 && DECL_EXPR_DECL (*tp) == dp->var) 3873 { 3874 tree init; 3875 if (DECL_INITIAL (dp->var) 3876 && DECL_INITIAL (dp->var) != error_mark_node) 3877 init = build2 (INIT_EXPR, void_type_node, dp->result, 3878 DECL_INITIAL (dp->var)); 3879 else 3880 init = build_empty_stmt (EXPR_LOCATION (*tp)); 3881 DECL_INITIAL (dp->var) = NULL_TREE; 3882 SET_EXPR_LOCATION (init, EXPR_LOCATION (*tp)); 3883 *tp = init; 3884 } 3885 /* And replace all uses of the NRV with the RESULT_DECL. */ 3886 else if (*tp == dp->var) 3887 *tp = dp->result; 3888 3889 /* Avoid walking into the same tree more than once. Unfortunately, we 3890 can't just use walk_tree_without duplicates because it would only call 3891 us for the first occurrence of dp->var in the function body. */ 3892 slot = htab_find_slot (dp->visited, *tp, INSERT); 3893 if (*slot) 3894 *walk_subtrees = 0; 3895 else 3896 *slot = *tp; 3897 3898 /* Keep iterating. */ 3899 return NULL_TREE; 3900 } 3901 3902 /* Called from finish_function to implement the named return value 3903 optimization by overriding all the RETURN_EXPRs and pertinent 3904 CLEANUP_STMTs and replacing all occurrences of VAR with RESULT, the 3905 RESULT_DECL for the function. */ 3906 3907 void 3908 finalize_nrv (tree *tp, tree var, tree result) 3909 { 3910 struct nrv_data data; 3911 3912 /* Copy name from VAR to RESULT. */ 3913 DECL_NAME (result) = DECL_NAME (var); 3914 /* Don't forget that we take its address. */ 3915 TREE_ADDRESSABLE (result) = TREE_ADDRESSABLE (var); 3916 /* Finally set DECL_VALUE_EXPR to avoid assigning 3917 a stack slot at -O0 for the original var and debug info 3918 uses RESULT location for VAR. */ 3919 SET_DECL_VALUE_EXPR (var, result); 3920 DECL_HAS_VALUE_EXPR_P (var) = 1; 3921 3922 data.var = var; 3923 data.result = result; 3924 data.visited = htab_create (37, htab_hash_pointer, htab_eq_pointer, NULL); 3925 cp_walk_tree (tp, finalize_nrv_r, &data, 0); 3926 htab_delete (data.visited); 3927 } 3928 3929 /* Create CP_OMP_CLAUSE_INFO for clause C. Returns true if it is invalid. */ 3930 3931 bool 3932 cxx_omp_create_clause_info (tree c, tree type, bool need_default_ctor, 3933 bool need_copy_ctor, bool need_copy_assignment) 3934 { 3935 int save_errorcount = errorcount; 3936 tree info, t; 3937 3938 /* Always allocate 3 elements for simplicity. These are the 3939 function decls for the ctor, dtor, and assignment op. 3940 This layout is known to the three lang hooks, 3941 cxx_omp_clause_default_init, cxx_omp_clause_copy_init, 3942 and cxx_omp_clause_assign_op. */ 3943 info = make_tree_vec (3); 3944 CP_OMP_CLAUSE_INFO (c) = info; 3945 3946 if (need_default_ctor || need_copy_ctor) 3947 { 3948 if (need_default_ctor) 3949 t = get_default_ctor (type); 3950 else 3951 t = get_copy_ctor (type, tf_warning_or_error); 3952 3953 if (t && !trivial_fn_p (t)) 3954 TREE_VEC_ELT (info, 0) = t; 3955 } 3956 3957 if ((need_default_ctor || need_copy_ctor) 3958 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)) 3959 TREE_VEC_ELT (info, 1) = get_dtor (type, tf_warning_or_error); 3960 3961 if (need_copy_assignment) 3962 { 3963 t = get_copy_assign (type); 3964 3965 if (t && !trivial_fn_p (t)) 3966 TREE_VEC_ELT (info, 2) = t; 3967 } 3968 3969 return errorcount != save_errorcount; 3970 } 3971 3972 /* For all elements of CLAUSES, validate them vs OpenMP constraints. 3973 Remove any elements from the list that are invalid. */ 3974 3975 tree 3976 finish_omp_clauses (tree clauses) 3977 { 3978 bitmap_head generic_head, firstprivate_head, lastprivate_head; 3979 tree c, t, *pc = &clauses; 3980 const char *name; 3981 3982 bitmap_obstack_initialize (NULL); 3983 bitmap_initialize (&generic_head, &bitmap_default_obstack); 3984 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack); 3985 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack); 3986 3987 for (pc = &clauses, c = clauses; c ; c = *pc) 3988 { 3989 bool remove = false; 3990 3991 switch (OMP_CLAUSE_CODE (c)) 3992 { 3993 case OMP_CLAUSE_SHARED: 3994 name = "shared"; 3995 goto check_dup_generic; 3996 case OMP_CLAUSE_PRIVATE: 3997 name = "private"; 3998 goto check_dup_generic; 3999 case OMP_CLAUSE_REDUCTION: 4000 name = "reduction"; 4001 goto check_dup_generic; 4002 case OMP_CLAUSE_COPYPRIVATE: 4003 name = "copyprivate"; 4004 goto check_dup_generic; 4005 case OMP_CLAUSE_COPYIN: 4006 name = "copyin"; 4007 goto check_dup_generic; 4008 check_dup_generic: 4009 t = OMP_CLAUSE_DECL (c); 4010 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 4011 { 4012 if (processing_template_decl) 4013 break; 4014 if (DECL_P (t)) 4015 error ("%qD is not a variable in clause %qs", t, name); 4016 else 4017 error ("%qE is not a variable in clause %qs", t, name); 4018 remove = true; 4019 } 4020 else if (bitmap_bit_p (&generic_head, DECL_UID (t)) 4021 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)) 4022 || bitmap_bit_p (&lastprivate_head, DECL_UID (t))) 4023 { 4024 error ("%qD appears more than once in data clauses", t); 4025 remove = true; 4026 } 4027 else 4028 bitmap_set_bit (&generic_head, DECL_UID (t)); 4029 break; 4030 4031 case OMP_CLAUSE_FIRSTPRIVATE: 4032 t = OMP_CLAUSE_DECL (c); 4033 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 4034 { 4035 if (processing_template_decl) 4036 break; 4037 if (DECL_P (t)) 4038 error ("%qD is not a variable in clause %<firstprivate%>", t); 4039 else 4040 error ("%qE is not a variable in clause %<firstprivate%>", t); 4041 remove = true; 4042 } 4043 else if (bitmap_bit_p (&generic_head, DECL_UID (t)) 4044 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))) 4045 { 4046 error ("%qD appears more than once in data clauses", t); 4047 remove = true; 4048 } 4049 else 4050 bitmap_set_bit (&firstprivate_head, DECL_UID (t)); 4051 break; 4052 4053 case OMP_CLAUSE_LASTPRIVATE: 4054 t = OMP_CLAUSE_DECL (c); 4055 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 4056 { 4057 if (processing_template_decl) 4058 break; 4059 if (DECL_P (t)) 4060 error ("%qD is not a variable in clause %<lastprivate%>", t); 4061 else 4062 error ("%qE is not a variable in clause %<lastprivate%>", t); 4063 remove = true; 4064 } 4065 else if (bitmap_bit_p (&generic_head, DECL_UID (t)) 4066 || bitmap_bit_p (&lastprivate_head, DECL_UID (t))) 4067 { 4068 error ("%qD appears more than once in data clauses", t); 4069 remove = true; 4070 } 4071 else 4072 bitmap_set_bit (&lastprivate_head, DECL_UID (t)); 4073 break; 4074 4075 case OMP_CLAUSE_IF: 4076 t = OMP_CLAUSE_IF_EXPR (c); 4077 t = maybe_convert_cond (t); 4078 if (t == error_mark_node) 4079 remove = true; 4080 else if (!processing_template_decl) 4081 t = fold_build_cleanup_point_expr (TREE_TYPE (t), t); 4082 OMP_CLAUSE_IF_EXPR (c) = t; 4083 break; 4084 4085 case OMP_CLAUSE_FINAL: 4086 t = OMP_CLAUSE_FINAL_EXPR (c); 4087 t = maybe_convert_cond (t); 4088 if (t == error_mark_node) 4089 remove = true; 4090 else if (!processing_template_decl) 4091 t = fold_build_cleanup_point_expr (TREE_TYPE (t), t); 4092 OMP_CLAUSE_FINAL_EXPR (c) = t; 4093 break; 4094 4095 case OMP_CLAUSE_NUM_THREADS: 4096 t = OMP_CLAUSE_NUM_THREADS_EXPR (c); 4097 if (t == error_mark_node) 4098 remove = true; 4099 else if (!type_dependent_expression_p (t) 4100 && !INTEGRAL_TYPE_P (TREE_TYPE (t))) 4101 { 4102 error ("num_threads expression must be integral"); 4103 remove = true; 4104 } 4105 else 4106 { 4107 t = mark_rvalue_use (t); 4108 if (!processing_template_decl) 4109 t = fold_build_cleanup_point_expr (TREE_TYPE (t), t); 4110 OMP_CLAUSE_NUM_THREADS_EXPR (c) = t; 4111 } 4112 break; 4113 4114 case OMP_CLAUSE_SCHEDULE: 4115 t = OMP_CLAUSE_SCHEDULE_CHUNK_EXPR (c); 4116 if (t == NULL) 4117 ; 4118 else if (t == error_mark_node) 4119 remove = true; 4120 else if (!type_dependent_expression_p (t) 4121 && !INTEGRAL_TYPE_P (TREE_TYPE (t))) 4122 { 4123 error ("schedule chunk size expression must be integral"); 4124 remove = true; 4125 } 4126 else 4127 { 4128 t = mark_rvalue_use (t); 4129 if (!processing_template_decl) 4130 t = fold_build_cleanup_point_expr (TREE_TYPE (t), t); 4131 OMP_CLAUSE_SCHEDULE_CHUNK_EXPR (c) = t; 4132 } 4133 break; 4134 4135 case OMP_CLAUSE_NOWAIT: 4136 case OMP_CLAUSE_ORDERED: 4137 case OMP_CLAUSE_DEFAULT: 4138 case OMP_CLAUSE_UNTIED: 4139 case OMP_CLAUSE_COLLAPSE: 4140 case OMP_CLAUSE_MERGEABLE: 4141 break; 4142 4143 default: 4144 gcc_unreachable (); 4145 } 4146 4147 if (remove) 4148 *pc = OMP_CLAUSE_CHAIN (c); 4149 else 4150 pc = &OMP_CLAUSE_CHAIN (c); 4151 } 4152 4153 for (pc = &clauses, c = clauses; c ; c = *pc) 4154 { 4155 enum omp_clause_code c_kind = OMP_CLAUSE_CODE (c); 4156 bool remove = false; 4157 bool need_complete_non_reference = false; 4158 bool need_default_ctor = false; 4159 bool need_copy_ctor = false; 4160 bool need_copy_assignment = false; 4161 bool need_implicitly_determined = false; 4162 tree type, inner_type; 4163 4164 switch (c_kind) 4165 { 4166 case OMP_CLAUSE_SHARED: 4167 name = "shared"; 4168 need_implicitly_determined = true; 4169 break; 4170 case OMP_CLAUSE_PRIVATE: 4171 name = "private"; 4172 need_complete_non_reference = true; 4173 need_default_ctor = true; 4174 need_implicitly_determined = true; 4175 break; 4176 case OMP_CLAUSE_FIRSTPRIVATE: 4177 name = "firstprivate"; 4178 need_complete_non_reference = true; 4179 need_copy_ctor = true; 4180 need_implicitly_determined = true; 4181 break; 4182 case OMP_CLAUSE_LASTPRIVATE: 4183 name = "lastprivate"; 4184 need_complete_non_reference = true; 4185 need_copy_assignment = true; 4186 need_implicitly_determined = true; 4187 break; 4188 case OMP_CLAUSE_REDUCTION: 4189 name = "reduction"; 4190 need_implicitly_determined = true; 4191 break; 4192 case OMP_CLAUSE_COPYPRIVATE: 4193 name = "copyprivate"; 4194 need_copy_assignment = true; 4195 break; 4196 case OMP_CLAUSE_COPYIN: 4197 name = "copyin"; 4198 need_copy_assignment = true; 4199 break; 4200 default: 4201 pc = &OMP_CLAUSE_CHAIN (c); 4202 continue; 4203 } 4204 4205 t = OMP_CLAUSE_DECL (c); 4206 if (processing_template_decl 4207 && TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 4208 { 4209 pc = &OMP_CLAUSE_CHAIN (c); 4210 continue; 4211 } 4212 4213 switch (c_kind) 4214 { 4215 case OMP_CLAUSE_LASTPRIVATE: 4216 if (!bitmap_bit_p (&firstprivate_head, DECL_UID (t))) 4217 need_default_ctor = true; 4218 break; 4219 4220 case OMP_CLAUSE_REDUCTION: 4221 if (AGGREGATE_TYPE_P (TREE_TYPE (t)) 4222 || POINTER_TYPE_P (TREE_TYPE (t))) 4223 { 4224 error ("%qE has invalid type for %<reduction%>", t); 4225 remove = true; 4226 } 4227 else if (FLOAT_TYPE_P (TREE_TYPE (t))) 4228 { 4229 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c); 4230 switch (r_code) 4231 { 4232 case PLUS_EXPR: 4233 case MULT_EXPR: 4234 case MINUS_EXPR: 4235 case MIN_EXPR: 4236 case MAX_EXPR: 4237 break; 4238 default: 4239 error ("%qE has invalid type for %<reduction(%s)%>", 4240 t, operator_name_info[r_code].name); 4241 remove = true; 4242 } 4243 } 4244 break; 4245 4246 case OMP_CLAUSE_COPYIN: 4247 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t)) 4248 { 4249 error ("%qE must be %<threadprivate%> for %<copyin%>", t); 4250 remove = true; 4251 } 4252 break; 4253 4254 default: 4255 break; 4256 } 4257 4258 if (need_complete_non_reference || need_copy_assignment) 4259 { 4260 t = require_complete_type (t); 4261 if (t == error_mark_node) 4262 remove = true; 4263 else if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE 4264 && need_complete_non_reference) 4265 { 4266 error ("%qE has reference type for %qs", t, name); 4267 remove = true; 4268 } 4269 } 4270 if (need_implicitly_determined) 4271 { 4272 const char *share_name = NULL; 4273 4274 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t)) 4275 share_name = "threadprivate"; 4276 else switch (cxx_omp_predetermined_sharing (t)) 4277 { 4278 case OMP_CLAUSE_DEFAULT_UNSPECIFIED: 4279 break; 4280 case OMP_CLAUSE_DEFAULT_SHARED: 4281 /* const vars may be specified in firstprivate clause. */ 4282 if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE 4283 && cxx_omp_const_qual_no_mutable (t)) 4284 break; 4285 share_name = "shared"; 4286 break; 4287 case OMP_CLAUSE_DEFAULT_PRIVATE: 4288 share_name = "private"; 4289 break; 4290 default: 4291 gcc_unreachable (); 4292 } 4293 if (share_name) 4294 { 4295 error ("%qE is predetermined %qs for %qs", 4296 t, share_name, name); 4297 remove = true; 4298 } 4299 } 4300 4301 /* We're interested in the base element, not arrays. */ 4302 inner_type = type = TREE_TYPE (t); 4303 while (TREE_CODE (inner_type) == ARRAY_TYPE) 4304 inner_type = TREE_TYPE (inner_type); 4305 4306 /* Check for special function availability by building a call to one. 4307 Save the results, because later we won't be in the right context 4308 for making these queries. */ 4309 if (CLASS_TYPE_P (inner_type) 4310 && COMPLETE_TYPE_P (inner_type) 4311 && (need_default_ctor || need_copy_ctor || need_copy_assignment) 4312 && !type_dependent_expression_p (t) 4313 && cxx_omp_create_clause_info (c, inner_type, need_default_ctor, 4314 need_copy_ctor, need_copy_assignment)) 4315 remove = true; 4316 4317 if (remove) 4318 *pc = OMP_CLAUSE_CHAIN (c); 4319 else 4320 pc = &OMP_CLAUSE_CHAIN (c); 4321 } 4322 4323 bitmap_obstack_release (NULL); 4324 return clauses; 4325 } 4326 4327 /* For all variables in the tree_list VARS, mark them as thread local. */ 4328 4329 void 4330 finish_omp_threadprivate (tree vars) 4331 { 4332 tree t; 4333 4334 /* Mark every variable in VARS to be assigned thread local storage. */ 4335 for (t = vars; t; t = TREE_CHAIN (t)) 4336 { 4337 tree v = TREE_PURPOSE (t); 4338 4339 if (error_operand_p (v)) 4340 ; 4341 else if (TREE_CODE (v) != VAR_DECL) 4342 error ("%<threadprivate%> %qD is not file, namespace " 4343 "or block scope variable", v); 4344 /* If V had already been marked threadprivate, it doesn't matter 4345 whether it had been used prior to this point. */ 4346 else if (TREE_USED (v) 4347 && (DECL_LANG_SPECIFIC (v) == NULL 4348 || !CP_DECL_THREADPRIVATE_P (v))) 4349 error ("%qE declared %<threadprivate%> after first use", v); 4350 else if (! TREE_STATIC (v) && ! DECL_EXTERNAL (v)) 4351 error ("automatic variable %qE cannot be %<threadprivate%>", v); 4352 else if (! COMPLETE_TYPE_P (TREE_TYPE (v))) 4353 error ("%<threadprivate%> %qE has incomplete type", v); 4354 else if (TREE_STATIC (v) && TYPE_P (CP_DECL_CONTEXT (v)) 4355 && CP_DECL_CONTEXT (v) != current_class_type) 4356 error ("%<threadprivate%> %qE directive not " 4357 "in %qT definition", v, CP_DECL_CONTEXT (v)); 4358 else 4359 { 4360 /* Allocate a LANG_SPECIFIC structure for V, if needed. */ 4361 if (DECL_LANG_SPECIFIC (v) == NULL) 4362 { 4363 retrofit_lang_decl (v); 4364 4365 /* Make sure that DECL_DISCRIMINATOR_P continues to be true 4366 after the allocation of the lang_decl structure. */ 4367 if (DECL_DISCRIMINATOR_P (v)) 4368 DECL_LANG_SPECIFIC (v)->u.base.u2sel = 1; 4369 } 4370 4371 if (! DECL_THREAD_LOCAL_P (v)) 4372 { 4373 DECL_TLS_MODEL (v) = decl_default_tls_model (v); 4374 /* If rtl has been already set for this var, call 4375 make_decl_rtl once again, so that encode_section_info 4376 has a chance to look at the new decl flags. */ 4377 if (DECL_RTL_SET_P (v)) 4378 make_decl_rtl (v); 4379 } 4380 CP_DECL_THREADPRIVATE_P (v) = 1; 4381 } 4382 } 4383 } 4384 4385 /* Build an OpenMP structured block. */ 4386 4387 tree 4388 begin_omp_structured_block (void) 4389 { 4390 return do_pushlevel (sk_omp); 4391 } 4392 4393 tree 4394 finish_omp_structured_block (tree block) 4395 { 4396 return do_poplevel (block); 4397 } 4398 4399 /* Similarly, except force the retention of the BLOCK. */ 4400 4401 tree 4402 begin_omp_parallel (void) 4403 { 4404 keep_next_level (true); 4405 return begin_omp_structured_block (); 4406 } 4407 4408 tree 4409 finish_omp_parallel (tree clauses, tree body) 4410 { 4411 tree stmt; 4412 4413 body = finish_omp_structured_block (body); 4414 4415 stmt = make_node (OMP_PARALLEL); 4416 TREE_TYPE (stmt) = void_type_node; 4417 OMP_PARALLEL_CLAUSES (stmt) = clauses; 4418 OMP_PARALLEL_BODY (stmt) = body; 4419 4420 return add_stmt (stmt); 4421 } 4422 4423 tree 4424 begin_omp_task (void) 4425 { 4426 keep_next_level (true); 4427 return begin_omp_structured_block (); 4428 } 4429 4430 tree 4431 finish_omp_task (tree clauses, tree body) 4432 { 4433 tree stmt; 4434 4435 body = finish_omp_structured_block (body); 4436 4437 stmt = make_node (OMP_TASK); 4438 TREE_TYPE (stmt) = void_type_node; 4439 OMP_TASK_CLAUSES (stmt) = clauses; 4440 OMP_TASK_BODY (stmt) = body; 4441 4442 return add_stmt (stmt); 4443 } 4444 4445 /* Helper function for finish_omp_for. Convert Ith random access iterator 4446 into integral iterator. Return FALSE if successful. */ 4447 4448 static bool 4449 handle_omp_for_class_iterator (int i, location_t locus, tree declv, tree initv, 4450 tree condv, tree incrv, tree *body, 4451 tree *pre_body, tree clauses) 4452 { 4453 tree diff, iter_init, iter_incr = NULL, last; 4454 tree incr_var = NULL, orig_pre_body, orig_body, c; 4455 tree decl = TREE_VEC_ELT (declv, i); 4456 tree init = TREE_VEC_ELT (initv, i); 4457 tree cond = TREE_VEC_ELT (condv, i); 4458 tree incr = TREE_VEC_ELT (incrv, i); 4459 tree iter = decl; 4460 location_t elocus = locus; 4461 4462 if (init && EXPR_HAS_LOCATION (init)) 4463 elocus = EXPR_LOCATION (init); 4464 4465 switch (TREE_CODE (cond)) 4466 { 4467 case GT_EXPR: 4468 case GE_EXPR: 4469 case LT_EXPR: 4470 case LE_EXPR: 4471 if (TREE_OPERAND (cond, 1) == iter) 4472 cond = build2 (swap_tree_comparison (TREE_CODE (cond)), 4473 TREE_TYPE (cond), iter, TREE_OPERAND (cond, 0)); 4474 if (TREE_OPERAND (cond, 0) != iter) 4475 cond = error_mark_node; 4476 else 4477 { 4478 tree tem = build_x_binary_op (TREE_CODE (cond), iter, ERROR_MARK, 4479 TREE_OPERAND (cond, 1), ERROR_MARK, 4480 NULL, tf_warning_or_error); 4481 if (error_operand_p (tem)) 4482 return true; 4483 } 4484 break; 4485 default: 4486 cond = error_mark_node; 4487 break; 4488 } 4489 if (cond == error_mark_node) 4490 { 4491 error_at (elocus, "invalid controlling predicate"); 4492 return true; 4493 } 4494 diff = build_x_binary_op (MINUS_EXPR, TREE_OPERAND (cond, 1), 4495 ERROR_MARK, iter, ERROR_MARK, NULL, 4496 tf_warning_or_error); 4497 if (error_operand_p (diff)) 4498 return true; 4499 if (TREE_CODE (TREE_TYPE (diff)) != INTEGER_TYPE) 4500 { 4501 error_at (elocus, "difference between %qE and %qD does not have integer type", 4502 TREE_OPERAND (cond, 1), iter); 4503 return true; 4504 } 4505 4506 switch (TREE_CODE (incr)) 4507 { 4508 case PREINCREMENT_EXPR: 4509 case PREDECREMENT_EXPR: 4510 case POSTINCREMENT_EXPR: 4511 case POSTDECREMENT_EXPR: 4512 if (TREE_OPERAND (incr, 0) != iter) 4513 { 4514 incr = error_mark_node; 4515 break; 4516 } 4517 iter_incr = build_x_unary_op (TREE_CODE (incr), iter, 4518 tf_warning_or_error); 4519 if (error_operand_p (iter_incr)) 4520 return true; 4521 else if (TREE_CODE (incr) == PREINCREMENT_EXPR 4522 || TREE_CODE (incr) == POSTINCREMENT_EXPR) 4523 incr = integer_one_node; 4524 else 4525 incr = integer_minus_one_node; 4526 break; 4527 case MODIFY_EXPR: 4528 if (TREE_OPERAND (incr, 0) != iter) 4529 incr = error_mark_node; 4530 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR 4531 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR) 4532 { 4533 tree rhs = TREE_OPERAND (incr, 1); 4534 if (TREE_OPERAND (rhs, 0) == iter) 4535 { 4536 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (rhs, 1))) 4537 != INTEGER_TYPE) 4538 incr = error_mark_node; 4539 else 4540 { 4541 iter_incr = build_x_modify_expr (iter, TREE_CODE (rhs), 4542 TREE_OPERAND (rhs, 1), 4543 tf_warning_or_error); 4544 if (error_operand_p (iter_incr)) 4545 return true; 4546 incr = TREE_OPERAND (rhs, 1); 4547 incr = cp_convert (TREE_TYPE (diff), incr); 4548 if (TREE_CODE (rhs) == MINUS_EXPR) 4549 { 4550 incr = build1 (NEGATE_EXPR, TREE_TYPE (diff), incr); 4551 incr = fold_if_not_in_template (incr); 4552 } 4553 if (TREE_CODE (incr) != INTEGER_CST 4554 && (TREE_CODE (incr) != NOP_EXPR 4555 || (TREE_CODE (TREE_OPERAND (incr, 0)) 4556 != INTEGER_CST))) 4557 iter_incr = NULL; 4558 } 4559 } 4560 else if (TREE_OPERAND (rhs, 1) == iter) 4561 { 4562 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (rhs, 0))) != INTEGER_TYPE 4563 || TREE_CODE (rhs) != PLUS_EXPR) 4564 incr = error_mark_node; 4565 else 4566 { 4567 iter_incr = build_x_binary_op (PLUS_EXPR, 4568 TREE_OPERAND (rhs, 0), 4569 ERROR_MARK, iter, 4570 ERROR_MARK, NULL, 4571 tf_warning_or_error); 4572 if (error_operand_p (iter_incr)) 4573 return true; 4574 iter_incr = build_x_modify_expr (iter, NOP_EXPR, 4575 iter_incr, 4576 tf_warning_or_error); 4577 if (error_operand_p (iter_incr)) 4578 return true; 4579 incr = TREE_OPERAND (rhs, 0); 4580 iter_incr = NULL; 4581 } 4582 } 4583 else 4584 incr = error_mark_node; 4585 } 4586 else 4587 incr = error_mark_node; 4588 break; 4589 default: 4590 incr = error_mark_node; 4591 break; 4592 } 4593 4594 if (incr == error_mark_node) 4595 { 4596 error_at (elocus, "invalid increment expression"); 4597 return true; 4598 } 4599 4600 incr = cp_convert (TREE_TYPE (diff), incr); 4601 for (c = clauses; c ; c = OMP_CLAUSE_CHAIN (c)) 4602 if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE 4603 && OMP_CLAUSE_DECL (c) == iter) 4604 break; 4605 4606 decl = create_temporary_var (TREE_TYPE (diff)); 4607 pushdecl (decl); 4608 add_decl_expr (decl); 4609 last = create_temporary_var (TREE_TYPE (diff)); 4610 pushdecl (last); 4611 add_decl_expr (last); 4612 if (c && iter_incr == NULL) 4613 { 4614 incr_var = create_temporary_var (TREE_TYPE (diff)); 4615 pushdecl (incr_var); 4616 add_decl_expr (incr_var); 4617 } 4618 gcc_assert (stmts_are_full_exprs_p ()); 4619 4620 orig_pre_body = *pre_body; 4621 *pre_body = push_stmt_list (); 4622 if (orig_pre_body) 4623 add_stmt (orig_pre_body); 4624 if (init != NULL) 4625 finish_expr_stmt (build_x_modify_expr (iter, NOP_EXPR, init, 4626 tf_warning_or_error)); 4627 init = build_int_cst (TREE_TYPE (diff), 0); 4628 if (c && iter_incr == NULL) 4629 { 4630 finish_expr_stmt (build_x_modify_expr (incr_var, NOP_EXPR, 4631 incr, tf_warning_or_error)); 4632 incr = incr_var; 4633 iter_incr = build_x_modify_expr (iter, PLUS_EXPR, incr, 4634 tf_warning_or_error); 4635 } 4636 finish_expr_stmt (build_x_modify_expr (last, NOP_EXPR, init, 4637 tf_warning_or_error)); 4638 *pre_body = pop_stmt_list (*pre_body); 4639 4640 cond = cp_build_binary_op (elocus, 4641 TREE_CODE (cond), decl, diff, 4642 tf_warning_or_error); 4643 incr = build_modify_expr (elocus, decl, NULL_TREE, PLUS_EXPR, 4644 elocus, incr, NULL_TREE); 4645 4646 orig_body = *body; 4647 *body = push_stmt_list (); 4648 iter_init = build2 (MINUS_EXPR, TREE_TYPE (diff), decl, last); 4649 iter_init = build_x_modify_expr (iter, PLUS_EXPR, iter_init, 4650 tf_warning_or_error); 4651 iter_init = build1 (NOP_EXPR, void_type_node, iter_init); 4652 finish_expr_stmt (iter_init); 4653 finish_expr_stmt (build_x_modify_expr (last, NOP_EXPR, decl, 4654 tf_warning_or_error)); 4655 add_stmt (orig_body); 4656 *body = pop_stmt_list (*body); 4657 4658 if (c) 4659 { 4660 OMP_CLAUSE_LASTPRIVATE_STMT (c) = push_stmt_list (); 4661 finish_expr_stmt (iter_incr); 4662 OMP_CLAUSE_LASTPRIVATE_STMT (c) 4663 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (c)); 4664 } 4665 4666 TREE_VEC_ELT (declv, i) = decl; 4667 TREE_VEC_ELT (initv, i) = init; 4668 TREE_VEC_ELT (condv, i) = cond; 4669 TREE_VEC_ELT (incrv, i) = incr; 4670 4671 return false; 4672 } 4673 4674 /* Build and validate an OMP_FOR statement. CLAUSES, BODY, COND, INCR 4675 are directly for their associated operands in the statement. DECL 4676 and INIT are a combo; if DECL is NULL then INIT ought to be a 4677 MODIFY_EXPR, and the DECL should be extracted. PRE_BODY are 4678 optional statements that need to go before the loop into its 4679 sk_omp scope. */ 4680 4681 tree 4682 finish_omp_for (location_t locus, tree declv, tree initv, tree condv, 4683 tree incrv, tree body, tree pre_body, tree clauses) 4684 { 4685 tree omp_for = NULL, orig_incr = NULL; 4686 tree decl, init, cond, incr; 4687 location_t elocus; 4688 int i; 4689 4690 gcc_assert (TREE_VEC_LENGTH (declv) == TREE_VEC_LENGTH (initv)); 4691 gcc_assert (TREE_VEC_LENGTH (declv) == TREE_VEC_LENGTH (condv)); 4692 gcc_assert (TREE_VEC_LENGTH (declv) == TREE_VEC_LENGTH (incrv)); 4693 for (i = 0; i < TREE_VEC_LENGTH (declv); i++) 4694 { 4695 decl = TREE_VEC_ELT (declv, i); 4696 init = TREE_VEC_ELT (initv, i); 4697 cond = TREE_VEC_ELT (condv, i); 4698 incr = TREE_VEC_ELT (incrv, i); 4699 elocus = locus; 4700 4701 if (decl == NULL) 4702 { 4703 if (init != NULL) 4704 switch (TREE_CODE (init)) 4705 { 4706 case MODIFY_EXPR: 4707 decl = TREE_OPERAND (init, 0); 4708 init = TREE_OPERAND (init, 1); 4709 break; 4710 case MODOP_EXPR: 4711 if (TREE_CODE (TREE_OPERAND (init, 1)) == NOP_EXPR) 4712 { 4713 decl = TREE_OPERAND (init, 0); 4714 init = TREE_OPERAND (init, 2); 4715 } 4716 break; 4717 default: 4718 break; 4719 } 4720 4721 if (decl == NULL) 4722 { 4723 error_at (locus, 4724 "expected iteration declaration or initialization"); 4725 return NULL; 4726 } 4727 } 4728 4729 if (init && EXPR_HAS_LOCATION (init)) 4730 elocus = EXPR_LOCATION (init); 4731 4732 if (cond == NULL) 4733 { 4734 error_at (elocus, "missing controlling predicate"); 4735 return NULL; 4736 } 4737 4738 if (incr == NULL) 4739 { 4740 error_at (elocus, "missing increment expression"); 4741 return NULL; 4742 } 4743 4744 TREE_VEC_ELT (declv, i) = decl; 4745 TREE_VEC_ELT (initv, i) = init; 4746 } 4747 4748 if (dependent_omp_for_p (declv, initv, condv, incrv)) 4749 { 4750 tree stmt; 4751 4752 stmt = make_node (OMP_FOR); 4753 4754 for (i = 0; i < TREE_VEC_LENGTH (declv); i++) 4755 { 4756 /* This is really just a place-holder. We'll be decomposing this 4757 again and going through the cp_build_modify_expr path below when 4758 we instantiate the thing. */ 4759 TREE_VEC_ELT (initv, i) 4760 = build2 (MODIFY_EXPR, void_type_node, TREE_VEC_ELT (declv, i), 4761 TREE_VEC_ELT (initv, i)); 4762 } 4763 4764 TREE_TYPE (stmt) = void_type_node; 4765 OMP_FOR_INIT (stmt) = initv; 4766 OMP_FOR_COND (stmt) = condv; 4767 OMP_FOR_INCR (stmt) = incrv; 4768 OMP_FOR_BODY (stmt) = body; 4769 OMP_FOR_PRE_BODY (stmt) = pre_body; 4770 OMP_FOR_CLAUSES (stmt) = clauses; 4771 4772 SET_EXPR_LOCATION (stmt, locus); 4773 return add_stmt (stmt); 4774 } 4775 4776 if (processing_template_decl) 4777 orig_incr = make_tree_vec (TREE_VEC_LENGTH (incrv)); 4778 4779 for (i = 0; i < TREE_VEC_LENGTH (declv); ) 4780 { 4781 decl = TREE_VEC_ELT (declv, i); 4782 init = TREE_VEC_ELT (initv, i); 4783 cond = TREE_VEC_ELT (condv, i); 4784 incr = TREE_VEC_ELT (incrv, i); 4785 if (orig_incr) 4786 TREE_VEC_ELT (orig_incr, i) = incr; 4787 elocus = locus; 4788 4789 if (init && EXPR_HAS_LOCATION (init)) 4790 elocus = EXPR_LOCATION (init); 4791 4792 if (!DECL_P (decl)) 4793 { 4794 error_at (elocus, "expected iteration declaration or initialization"); 4795 return NULL; 4796 } 4797 4798 if (incr && TREE_CODE (incr) == MODOP_EXPR) 4799 { 4800 if (orig_incr) 4801 TREE_VEC_ELT (orig_incr, i) = incr; 4802 incr = cp_build_modify_expr (TREE_OPERAND (incr, 0), 4803 TREE_CODE (TREE_OPERAND (incr, 1)), 4804 TREE_OPERAND (incr, 2), 4805 tf_warning_or_error); 4806 } 4807 4808 if (CLASS_TYPE_P (TREE_TYPE (decl))) 4809 { 4810 if (handle_omp_for_class_iterator (i, locus, declv, initv, condv, 4811 incrv, &body, &pre_body, clauses)) 4812 return NULL; 4813 continue; 4814 } 4815 4816 if (!INTEGRAL_TYPE_P (TREE_TYPE (decl)) 4817 && TREE_CODE (TREE_TYPE (decl)) != POINTER_TYPE) 4818 { 4819 error_at (elocus, "invalid type for iteration variable %qE", decl); 4820 return NULL; 4821 } 4822 4823 if (!processing_template_decl) 4824 { 4825 init = fold_build_cleanup_point_expr (TREE_TYPE (init), init); 4826 init = cp_build_modify_expr (decl, NOP_EXPR, init, tf_warning_or_error); 4827 } 4828 else 4829 init = build2 (MODIFY_EXPR, void_type_node, decl, init); 4830 if (cond 4831 && TREE_SIDE_EFFECTS (cond) 4832 && COMPARISON_CLASS_P (cond) 4833 && !processing_template_decl) 4834 { 4835 tree t = TREE_OPERAND (cond, 0); 4836 if (TREE_SIDE_EFFECTS (t) 4837 && t != decl 4838 && (TREE_CODE (t) != NOP_EXPR 4839 || TREE_OPERAND (t, 0) != decl)) 4840 TREE_OPERAND (cond, 0) 4841 = fold_build_cleanup_point_expr (TREE_TYPE (t), t); 4842 4843 t = TREE_OPERAND (cond, 1); 4844 if (TREE_SIDE_EFFECTS (t) 4845 && t != decl 4846 && (TREE_CODE (t) != NOP_EXPR 4847 || TREE_OPERAND (t, 0) != decl)) 4848 TREE_OPERAND (cond, 1) 4849 = fold_build_cleanup_point_expr (TREE_TYPE (t), t); 4850 } 4851 if (decl == error_mark_node || init == error_mark_node) 4852 return NULL; 4853 4854 TREE_VEC_ELT (declv, i) = decl; 4855 TREE_VEC_ELT (initv, i) = init; 4856 TREE_VEC_ELT (condv, i) = cond; 4857 TREE_VEC_ELT (incrv, i) = incr; 4858 i++; 4859 } 4860 4861 if (IS_EMPTY_STMT (pre_body)) 4862 pre_body = NULL; 4863 4864 omp_for = c_finish_omp_for (locus, declv, initv, condv, incrv, 4865 body, pre_body); 4866 4867 if (omp_for == NULL) 4868 return NULL; 4869 4870 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INCR (omp_for)); i++) 4871 { 4872 decl = TREE_OPERAND (TREE_VEC_ELT (OMP_FOR_INIT (omp_for), i), 0); 4873 incr = TREE_VEC_ELT (OMP_FOR_INCR (omp_for), i); 4874 4875 if (TREE_CODE (incr) != MODIFY_EXPR) 4876 continue; 4877 4878 if (TREE_SIDE_EFFECTS (TREE_OPERAND (incr, 1)) 4879 && BINARY_CLASS_P (TREE_OPERAND (incr, 1)) 4880 && !processing_template_decl) 4881 { 4882 tree t = TREE_OPERAND (TREE_OPERAND (incr, 1), 0); 4883 if (TREE_SIDE_EFFECTS (t) 4884 && t != decl 4885 && (TREE_CODE (t) != NOP_EXPR 4886 || TREE_OPERAND (t, 0) != decl)) 4887 TREE_OPERAND (TREE_OPERAND (incr, 1), 0) 4888 = fold_build_cleanup_point_expr (TREE_TYPE (t), t); 4889 4890 t = TREE_OPERAND (TREE_OPERAND (incr, 1), 1); 4891 if (TREE_SIDE_EFFECTS (t) 4892 && t != decl 4893 && (TREE_CODE (t) != NOP_EXPR 4894 || TREE_OPERAND (t, 0) != decl)) 4895 TREE_OPERAND (TREE_OPERAND (incr, 1), 1) 4896 = fold_build_cleanup_point_expr (TREE_TYPE (t), t); 4897 } 4898 4899 if (orig_incr) 4900 TREE_VEC_ELT (OMP_FOR_INCR (omp_for), i) = TREE_VEC_ELT (orig_incr, i); 4901 } 4902 if (omp_for != NULL) 4903 OMP_FOR_CLAUSES (omp_for) = clauses; 4904 return omp_for; 4905 } 4906 4907 void 4908 finish_omp_atomic (enum tree_code code, enum tree_code opcode, tree lhs, 4909 tree rhs, tree v, tree lhs1, tree rhs1) 4910 { 4911 tree orig_lhs; 4912 tree orig_rhs; 4913 tree orig_v; 4914 tree orig_lhs1; 4915 tree orig_rhs1; 4916 bool dependent_p; 4917 tree stmt; 4918 4919 orig_lhs = lhs; 4920 orig_rhs = rhs; 4921 orig_v = v; 4922 orig_lhs1 = lhs1; 4923 orig_rhs1 = rhs1; 4924 dependent_p = false; 4925 stmt = NULL_TREE; 4926 4927 /* Even in a template, we can detect invalid uses of the atomic 4928 pragma if neither LHS nor RHS is type-dependent. */ 4929 if (processing_template_decl) 4930 { 4931 dependent_p = (type_dependent_expression_p (lhs) 4932 || (rhs && type_dependent_expression_p (rhs)) 4933 || (v && type_dependent_expression_p (v)) 4934 || (lhs1 && type_dependent_expression_p (lhs1)) 4935 || (rhs1 && type_dependent_expression_p (rhs1))); 4936 if (!dependent_p) 4937 { 4938 lhs = build_non_dependent_expr (lhs); 4939 if (rhs) 4940 rhs = build_non_dependent_expr (rhs); 4941 if (v) 4942 v = build_non_dependent_expr (v); 4943 if (lhs1) 4944 lhs1 = build_non_dependent_expr (lhs1); 4945 if (rhs1) 4946 rhs1 = build_non_dependent_expr (rhs1); 4947 } 4948 } 4949 if (!dependent_p) 4950 { 4951 stmt = c_finish_omp_atomic (input_location, code, opcode, lhs, rhs, 4952 v, lhs1, rhs1); 4953 if (stmt == error_mark_node) 4954 return; 4955 } 4956 if (processing_template_decl) 4957 { 4958 if (code == OMP_ATOMIC_READ) 4959 { 4960 stmt = build_min_nt (OMP_ATOMIC_READ, orig_lhs); 4961 stmt = build2 (MODIFY_EXPR, void_type_node, orig_v, stmt); 4962 } 4963 else 4964 { 4965 if (opcode == NOP_EXPR) 4966 stmt = build2 (MODIFY_EXPR, void_type_node, orig_lhs, orig_rhs); 4967 else 4968 stmt = build2 (opcode, void_type_node, orig_lhs, orig_rhs); 4969 if (orig_rhs1) 4970 stmt = build_min_nt (COMPOUND_EXPR, orig_rhs1, stmt); 4971 if (code != OMP_ATOMIC) 4972 { 4973 stmt = build_min_nt (code, orig_lhs1, stmt); 4974 stmt = build2 (MODIFY_EXPR, void_type_node, orig_v, stmt); 4975 } 4976 } 4977 stmt = build2 (OMP_ATOMIC, void_type_node, integer_zero_node, stmt); 4978 } 4979 add_stmt (stmt); 4980 } 4981 4982 void 4983 finish_omp_barrier (void) 4984 { 4985 tree fn = builtin_decl_explicit (BUILT_IN_GOMP_BARRIER); 4986 VEC(tree,gc) *vec = make_tree_vector (); 4987 tree stmt = finish_call_expr (fn, &vec, false, false, tf_warning_or_error); 4988 release_tree_vector (vec); 4989 finish_expr_stmt (stmt); 4990 } 4991 4992 void 4993 finish_omp_flush (void) 4994 { 4995 tree fn = builtin_decl_explicit (BUILT_IN_SYNC_SYNCHRONIZE); 4996 VEC(tree,gc) *vec = make_tree_vector (); 4997 tree stmt = finish_call_expr (fn, &vec, false, false, tf_warning_or_error); 4998 release_tree_vector (vec); 4999 finish_expr_stmt (stmt); 5000 } 5001 5002 void 5003 finish_omp_taskwait (void) 5004 { 5005 tree fn = builtin_decl_explicit (BUILT_IN_GOMP_TASKWAIT); 5006 VEC(tree,gc) *vec = make_tree_vector (); 5007 tree stmt = finish_call_expr (fn, &vec, false, false, tf_warning_or_error); 5008 release_tree_vector (vec); 5009 finish_expr_stmt (stmt); 5010 } 5011 5012 void 5013 finish_omp_taskyield (void) 5014 { 5015 tree fn = builtin_decl_explicit (BUILT_IN_GOMP_TASKYIELD); 5016 VEC(tree,gc) *vec = make_tree_vector (); 5017 tree stmt = finish_call_expr (fn, &vec, false, false, tf_warning_or_error); 5018 release_tree_vector (vec); 5019 finish_expr_stmt (stmt); 5020 } 5021 5022 /* Begin a __transaction_atomic or __transaction_relaxed statement. 5023 If PCOMPOUND is non-null, this is for a function-transaction-block, and we 5024 should create an extra compound stmt. */ 5025 5026 tree 5027 begin_transaction_stmt (location_t loc, tree *pcompound, int flags) 5028 { 5029 tree r; 5030 5031 if (pcompound) 5032 *pcompound = begin_compound_stmt (0); 5033 5034 r = build_stmt (loc, TRANSACTION_EXPR, NULL_TREE); 5035 5036 /* Only add the statement to the function if support enabled. */ 5037 if (flag_tm) 5038 add_stmt (r); 5039 else 5040 error_at (loc, ((flags & TM_STMT_ATTR_RELAXED) != 0 5041 ? G_("%<__transaction_relaxed%> without " 5042 "transactional memory support enabled") 5043 : G_("%<__transaction_atomic%> without " 5044 "transactional memory support enabled"))); 5045 5046 TRANSACTION_EXPR_BODY (r) = push_stmt_list (); 5047 return r; 5048 } 5049 5050 /* End a __transaction_atomic or __transaction_relaxed statement. 5051 If COMPOUND_STMT is non-null, this is for a function-transaction-block, 5052 and we should end the compound. If NOEX is non-NULL, we wrap the body in 5053 a MUST_NOT_THROW_EXPR with NOEX as condition. */ 5054 5055 void 5056 finish_transaction_stmt (tree stmt, tree compound_stmt, int flags, tree noex) 5057 { 5058 TRANSACTION_EXPR_BODY (stmt) = pop_stmt_list (TRANSACTION_EXPR_BODY (stmt)); 5059 TRANSACTION_EXPR_OUTER (stmt) = (flags & TM_STMT_ATTR_OUTER) != 0; 5060 TRANSACTION_EXPR_RELAXED (stmt) = (flags & TM_STMT_ATTR_RELAXED) != 0; 5061 TRANSACTION_EXPR_IS_STMT (stmt) = 1; 5062 5063 /* noexcept specifications are not allowed for function transactions. */ 5064 gcc_assert (!(noex && compound_stmt)); 5065 if (noex) 5066 { 5067 tree body = build_must_not_throw_expr (TRANSACTION_EXPR_BODY (stmt), 5068 noex); 5069 SET_EXPR_LOCATION (body, EXPR_LOCATION (TRANSACTION_EXPR_BODY (stmt))); 5070 TREE_SIDE_EFFECTS (body) = 1; 5071 TRANSACTION_EXPR_BODY (stmt) = body; 5072 } 5073 5074 if (compound_stmt) 5075 finish_compound_stmt (compound_stmt); 5076 finish_stmt (); 5077 } 5078 5079 /* Build a __transaction_atomic or __transaction_relaxed expression. If 5080 NOEX is non-NULL, we wrap the body in a MUST_NOT_THROW_EXPR with NOEX as 5081 condition. */ 5082 5083 tree 5084 build_transaction_expr (location_t loc, tree expr, int flags, tree noex) 5085 { 5086 tree ret; 5087 if (noex) 5088 { 5089 expr = build_must_not_throw_expr (expr, noex); 5090 SET_EXPR_LOCATION (expr, loc); 5091 TREE_SIDE_EFFECTS (expr) = 1; 5092 } 5093 ret = build1 (TRANSACTION_EXPR, TREE_TYPE (expr), expr); 5094 if (flags & TM_STMT_ATTR_RELAXED) 5095 TRANSACTION_EXPR_RELAXED (ret) = 1; 5096 SET_EXPR_LOCATION (ret, loc); 5097 return ret; 5098 } 5099 5100 void 5101 init_cp_semantics (void) 5102 { 5103 } 5104 5105 /* Build a STATIC_ASSERT for a static assertion with the condition 5106 CONDITION and the message text MESSAGE. LOCATION is the location 5107 of the static assertion in the source code. When MEMBER_P, this 5108 static assertion is a member of a class. */ 5109 void 5110 finish_static_assert (tree condition, tree message, location_t location, 5111 bool member_p) 5112 { 5113 if (check_for_bare_parameter_packs (condition)) 5114 condition = error_mark_node; 5115 5116 if (type_dependent_expression_p (condition) 5117 || value_dependent_expression_p (condition)) 5118 { 5119 /* We're in a template; build a STATIC_ASSERT and put it in 5120 the right place. */ 5121 tree assertion; 5122 5123 assertion = make_node (STATIC_ASSERT); 5124 STATIC_ASSERT_CONDITION (assertion) = condition; 5125 STATIC_ASSERT_MESSAGE (assertion) = message; 5126 STATIC_ASSERT_SOURCE_LOCATION (assertion) = location; 5127 5128 if (member_p) 5129 maybe_add_class_template_decl_list (current_class_type, 5130 assertion, 5131 /*friend_p=*/0); 5132 else 5133 add_stmt (assertion); 5134 5135 return; 5136 } 5137 5138 /* Fold the expression and convert it to a boolean value. */ 5139 condition = fold_non_dependent_expr (condition); 5140 condition = cp_convert (boolean_type_node, condition); 5141 condition = maybe_constant_value (condition); 5142 5143 if (TREE_CODE (condition) == INTEGER_CST && !integer_zerop (condition)) 5144 /* Do nothing; the condition is satisfied. */ 5145 ; 5146 else 5147 { 5148 location_t saved_loc = input_location; 5149 5150 input_location = location; 5151 if (TREE_CODE (condition) == INTEGER_CST 5152 && integer_zerop (condition)) 5153 /* Report the error. */ 5154 error ("static assertion failed: %s", TREE_STRING_POINTER (message)); 5155 else if (condition && condition != error_mark_node) 5156 { 5157 error ("non-constant condition for static assertion"); 5158 cxx_constant_value (condition); 5159 } 5160 input_location = saved_loc; 5161 } 5162 } 5163 5164 /* Implements the C++0x decltype keyword. Returns the type of EXPR, 5165 suitable for use as a type-specifier. 5166 5167 ID_EXPRESSION_OR_MEMBER_ACCESS_P is true when EXPR was parsed as an 5168 id-expression or a class member access, FALSE when it was parsed as 5169 a full expression. */ 5170 5171 tree 5172 finish_decltype_type (tree expr, bool id_expression_or_member_access_p, 5173 tsubst_flags_t complain) 5174 { 5175 tree type = NULL_TREE; 5176 5177 if (!expr || error_operand_p (expr)) 5178 return error_mark_node; 5179 5180 if (TYPE_P (expr) 5181 || TREE_CODE (expr) == TYPE_DECL 5182 || (TREE_CODE (expr) == BIT_NOT_EXPR 5183 && TYPE_P (TREE_OPERAND (expr, 0)))) 5184 { 5185 if (complain & tf_error) 5186 error ("argument to decltype must be an expression"); 5187 return error_mark_node; 5188 } 5189 5190 /* FIXME instantiation-dependent */ 5191 if (type_dependent_expression_p (expr) 5192 /* In a template, a COMPONENT_REF has an IDENTIFIER_NODE for op1 even 5193 if it isn't dependent, so that we can check access control at 5194 instantiation time, so defer the decltype as well (PR 42277). */ 5195 || (id_expression_or_member_access_p 5196 && processing_template_decl 5197 && TREE_CODE (expr) == COMPONENT_REF)) 5198 { 5199 type = cxx_make_type (DECLTYPE_TYPE); 5200 DECLTYPE_TYPE_EXPR (type) = expr; 5201 DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (type) 5202 = id_expression_or_member_access_p; 5203 SET_TYPE_STRUCTURAL_EQUALITY (type); 5204 5205 return type; 5206 } 5207 5208 /* The type denoted by decltype(e) is defined as follows: */ 5209 5210 expr = resolve_nondeduced_context (expr); 5211 5212 if (type_unknown_p (expr)) 5213 { 5214 if (complain & tf_error) 5215 error ("decltype cannot resolve address of overloaded function"); 5216 return error_mark_node; 5217 } 5218 5219 if (invalid_nonstatic_memfn_p (expr, complain)) 5220 return error_mark_node; 5221 5222 /* To get the size of a static data member declared as an array of 5223 unknown bound, we need to instantiate it. */ 5224 if (TREE_CODE (expr) == VAR_DECL 5225 && VAR_HAD_UNKNOWN_BOUND (expr) 5226 && DECL_TEMPLATE_INSTANTIATION (expr)) 5227 instantiate_decl (expr, /*defer_ok*/true, /*expl_inst_mem*/false); 5228 5229 if (id_expression_or_member_access_p) 5230 { 5231 /* If e is an id-expression or a class member access (5.2.5 5232 [expr.ref]), decltype(e) is defined as the type of the entity 5233 named by e. If there is no such entity, or e names a set of 5234 overloaded functions, the program is ill-formed. */ 5235 if (TREE_CODE (expr) == IDENTIFIER_NODE) 5236 expr = lookup_name (expr); 5237 5238 if (TREE_CODE (expr) == INDIRECT_REF) 5239 /* This can happen when the expression is, e.g., "a.b". Just 5240 look at the underlying operand. */ 5241 expr = TREE_OPERAND (expr, 0); 5242 5243 if (TREE_CODE (expr) == OFFSET_REF 5244 || TREE_CODE (expr) == MEMBER_REF) 5245 /* We're only interested in the field itself. If it is a 5246 BASELINK, we will need to see through it in the next 5247 step. */ 5248 expr = TREE_OPERAND (expr, 1); 5249 5250 if (BASELINK_P (expr)) 5251 /* See through BASELINK nodes to the underlying function. */ 5252 expr = BASELINK_FUNCTIONS (expr); 5253 5254 switch (TREE_CODE (expr)) 5255 { 5256 case FIELD_DECL: 5257 if (DECL_BIT_FIELD_TYPE (expr)) 5258 { 5259 type = DECL_BIT_FIELD_TYPE (expr); 5260 break; 5261 } 5262 /* Fall through for fields that aren't bitfields. */ 5263 5264 case FUNCTION_DECL: 5265 case VAR_DECL: 5266 case CONST_DECL: 5267 case PARM_DECL: 5268 case RESULT_DECL: 5269 case TEMPLATE_PARM_INDEX: 5270 expr = mark_type_use (expr); 5271 type = TREE_TYPE (expr); 5272 break; 5273 5274 case ERROR_MARK: 5275 type = error_mark_node; 5276 break; 5277 5278 case COMPONENT_REF: 5279 mark_type_use (expr); 5280 type = is_bitfield_expr_with_lowered_type (expr); 5281 if (!type) 5282 type = TREE_TYPE (TREE_OPERAND (expr, 1)); 5283 break; 5284 5285 case BIT_FIELD_REF: 5286 gcc_unreachable (); 5287 5288 case INTEGER_CST: 5289 case PTRMEM_CST: 5290 /* We can get here when the id-expression refers to an 5291 enumerator or non-type template parameter. */ 5292 type = TREE_TYPE (expr); 5293 break; 5294 5295 default: 5296 gcc_unreachable (); 5297 return error_mark_node; 5298 } 5299 } 5300 else 5301 { 5302 /* Within a lambda-expression: 5303 5304 Every occurrence of decltype((x)) where x is a possibly 5305 parenthesized id-expression that names an entity of 5306 automatic storage duration is treated as if x were 5307 transformed into an access to a corresponding data member 5308 of the closure type that would have been declared if x 5309 were a use of the denoted entity. */ 5310 if (outer_automatic_var_p (expr) 5311 && current_function_decl 5312 && LAMBDA_FUNCTION_P (current_function_decl)) 5313 type = capture_decltype (expr); 5314 else if (error_operand_p (expr)) 5315 type = error_mark_node; 5316 else if (expr == current_class_ptr) 5317 /* If the expression is just "this", we want the 5318 cv-unqualified pointer for the "this" type. */ 5319 type = TYPE_MAIN_VARIANT (TREE_TYPE (expr)); 5320 else 5321 { 5322 /* Otherwise, where T is the type of e, if e is an lvalue, 5323 decltype(e) is defined as T&; if an xvalue, T&&; otherwise, T. */ 5324 cp_lvalue_kind clk = lvalue_kind (expr); 5325 type = unlowered_expr_type (expr); 5326 gcc_assert (TREE_CODE (type) != REFERENCE_TYPE); 5327 if (clk != clk_none && !(clk & clk_class)) 5328 type = cp_build_reference_type (type, (clk & clk_rvalueref)); 5329 } 5330 } 5331 5332 return type; 5333 } 5334 5335 /* Called from trait_expr_value to evaluate either __has_nothrow_assign or 5336 __has_nothrow_copy, depending on assign_p. */ 5337 5338 static bool 5339 classtype_has_nothrow_assign_or_copy_p (tree type, bool assign_p) 5340 { 5341 tree fns; 5342 5343 if (assign_p) 5344 { 5345 int ix; 5346 ix = lookup_fnfields_1 (type, ansi_assopname (NOP_EXPR)); 5347 if (ix < 0) 5348 return false; 5349 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (type), ix); 5350 } 5351 else if (TYPE_HAS_COPY_CTOR (type)) 5352 { 5353 /* If construction of the copy constructor was postponed, create 5354 it now. */ 5355 if (CLASSTYPE_LAZY_COPY_CTOR (type)) 5356 lazily_declare_fn (sfk_copy_constructor, type); 5357 if (CLASSTYPE_LAZY_MOVE_CTOR (type)) 5358 lazily_declare_fn (sfk_move_constructor, type); 5359 fns = CLASSTYPE_CONSTRUCTORS (type); 5360 } 5361 else 5362 return false; 5363 5364 for (; fns; fns = OVL_NEXT (fns)) 5365 { 5366 tree fn = OVL_CURRENT (fns); 5367 5368 if (assign_p) 5369 { 5370 if (copy_fn_p (fn) == 0) 5371 continue; 5372 } 5373 else if (copy_fn_p (fn) <= 0) 5374 continue; 5375 5376 maybe_instantiate_noexcept (fn); 5377 if (!TYPE_NOTHROW_P (TREE_TYPE (fn))) 5378 return false; 5379 } 5380 5381 return true; 5382 } 5383 5384 /* Actually evaluates the trait. */ 5385 5386 static bool 5387 trait_expr_value (cp_trait_kind kind, tree type1, tree type2) 5388 { 5389 enum tree_code type_code1; 5390 tree t; 5391 5392 type_code1 = TREE_CODE (type1); 5393 5394 switch (kind) 5395 { 5396 case CPTK_HAS_NOTHROW_ASSIGN: 5397 type1 = strip_array_types (type1); 5398 return (!CP_TYPE_CONST_P (type1) && type_code1 != REFERENCE_TYPE 5399 && (trait_expr_value (CPTK_HAS_TRIVIAL_ASSIGN, type1, type2) 5400 || (CLASS_TYPE_P (type1) 5401 && classtype_has_nothrow_assign_or_copy_p (type1, 5402 true)))); 5403 5404 case CPTK_HAS_TRIVIAL_ASSIGN: 5405 /* ??? The standard seems to be missing the "or array of such a class 5406 type" wording for this trait. */ 5407 type1 = strip_array_types (type1); 5408 return (!CP_TYPE_CONST_P (type1) && type_code1 != REFERENCE_TYPE 5409 && (trivial_type_p (type1) 5410 || (CLASS_TYPE_P (type1) 5411 && TYPE_HAS_TRIVIAL_COPY_ASSIGN (type1)))); 5412 5413 case CPTK_HAS_NOTHROW_CONSTRUCTOR: 5414 type1 = strip_array_types (type1); 5415 return (trait_expr_value (CPTK_HAS_TRIVIAL_CONSTRUCTOR, type1, type2) 5416 || (CLASS_TYPE_P (type1) 5417 && (t = locate_ctor (type1)) 5418 && (maybe_instantiate_noexcept (t), 5419 TYPE_NOTHROW_P (TREE_TYPE (t))))); 5420 5421 case CPTK_HAS_TRIVIAL_CONSTRUCTOR: 5422 type1 = strip_array_types (type1); 5423 return (trivial_type_p (type1) 5424 || (CLASS_TYPE_P (type1) && TYPE_HAS_TRIVIAL_DFLT (type1))); 5425 5426 case CPTK_HAS_NOTHROW_COPY: 5427 type1 = strip_array_types (type1); 5428 return (trait_expr_value (CPTK_HAS_TRIVIAL_COPY, type1, type2) 5429 || (CLASS_TYPE_P (type1) 5430 && classtype_has_nothrow_assign_or_copy_p (type1, false))); 5431 5432 case CPTK_HAS_TRIVIAL_COPY: 5433 /* ??? The standard seems to be missing the "or array of such a class 5434 type" wording for this trait. */ 5435 type1 = strip_array_types (type1); 5436 return (trivial_type_p (type1) || type_code1 == REFERENCE_TYPE 5437 || (CLASS_TYPE_P (type1) && TYPE_HAS_TRIVIAL_COPY_CTOR (type1))); 5438 5439 case CPTK_HAS_TRIVIAL_DESTRUCTOR: 5440 type1 = strip_array_types (type1); 5441 return (trivial_type_p (type1) || type_code1 == REFERENCE_TYPE 5442 || (CLASS_TYPE_P (type1) 5443 && TYPE_HAS_TRIVIAL_DESTRUCTOR (type1))); 5444 5445 case CPTK_HAS_VIRTUAL_DESTRUCTOR: 5446 return type_has_virtual_destructor (type1); 5447 5448 case CPTK_IS_ABSTRACT: 5449 return (CLASS_TYPE_P (type1) && CLASSTYPE_PURE_VIRTUALS (type1)); 5450 5451 case CPTK_IS_BASE_OF: 5452 return (NON_UNION_CLASS_TYPE_P (type1) && NON_UNION_CLASS_TYPE_P (type2) 5453 && DERIVED_FROM_P (type1, type2)); 5454 5455 case CPTK_IS_CLASS: 5456 return (NON_UNION_CLASS_TYPE_P (type1)); 5457 5458 case CPTK_IS_CONVERTIBLE_TO: 5459 /* TODO */ 5460 return false; 5461 5462 case CPTK_IS_EMPTY: 5463 return (NON_UNION_CLASS_TYPE_P (type1) && CLASSTYPE_EMPTY_P (type1)); 5464 5465 case CPTK_IS_ENUM: 5466 return (type_code1 == ENUMERAL_TYPE); 5467 5468 case CPTK_IS_FINAL: 5469 return (CLASS_TYPE_P (type1) && CLASSTYPE_FINAL (type1)); 5470 5471 case CPTK_IS_LITERAL_TYPE: 5472 return (literal_type_p (type1)); 5473 5474 case CPTK_IS_POD: 5475 return (pod_type_p (type1)); 5476 5477 case CPTK_IS_POLYMORPHIC: 5478 return (CLASS_TYPE_P (type1) && TYPE_POLYMORPHIC_P (type1)); 5479 5480 case CPTK_IS_STD_LAYOUT: 5481 return (std_layout_type_p (type1)); 5482 5483 case CPTK_IS_TRIVIAL: 5484 return (trivial_type_p (type1)); 5485 5486 case CPTK_IS_UNION: 5487 return (type_code1 == UNION_TYPE); 5488 5489 default: 5490 gcc_unreachable (); 5491 return false; 5492 } 5493 } 5494 5495 /* If TYPE is an array of unknown bound, or (possibly cv-qualified) 5496 void, or a complete type, returns it, otherwise NULL_TREE. */ 5497 5498 static tree 5499 check_trait_type (tree type) 5500 { 5501 if (TREE_CODE (type) == ARRAY_TYPE && !TYPE_DOMAIN (type) 5502 && COMPLETE_TYPE_P (TREE_TYPE (type))) 5503 return type; 5504 5505 if (VOID_TYPE_P (type)) 5506 return type; 5507 5508 return complete_type_or_else (strip_array_types (type), NULL_TREE); 5509 } 5510 5511 /* Process a trait expression. */ 5512 5513 tree 5514 finish_trait_expr (cp_trait_kind kind, tree type1, tree type2) 5515 { 5516 gcc_assert (kind == CPTK_HAS_NOTHROW_ASSIGN 5517 || kind == CPTK_HAS_NOTHROW_CONSTRUCTOR 5518 || kind == CPTK_HAS_NOTHROW_COPY 5519 || kind == CPTK_HAS_TRIVIAL_ASSIGN 5520 || kind == CPTK_HAS_TRIVIAL_CONSTRUCTOR 5521 || kind == CPTK_HAS_TRIVIAL_COPY 5522 || kind == CPTK_HAS_TRIVIAL_DESTRUCTOR 5523 || kind == CPTK_HAS_VIRTUAL_DESTRUCTOR 5524 || kind == CPTK_IS_ABSTRACT 5525 || kind == CPTK_IS_BASE_OF 5526 || kind == CPTK_IS_CLASS 5527 || kind == CPTK_IS_CONVERTIBLE_TO 5528 || kind == CPTK_IS_EMPTY 5529 || kind == CPTK_IS_ENUM 5530 || kind == CPTK_IS_FINAL 5531 || kind == CPTK_IS_LITERAL_TYPE 5532 || kind == CPTK_IS_POD 5533 || kind == CPTK_IS_POLYMORPHIC 5534 || kind == CPTK_IS_STD_LAYOUT 5535 || kind == CPTK_IS_TRIVIAL 5536 || kind == CPTK_IS_UNION); 5537 5538 if (kind == CPTK_IS_CONVERTIBLE_TO) 5539 { 5540 sorry ("__is_convertible_to"); 5541 return error_mark_node; 5542 } 5543 5544 if (type1 == error_mark_node 5545 || ((kind == CPTK_IS_BASE_OF || kind == CPTK_IS_CONVERTIBLE_TO) 5546 && type2 == error_mark_node)) 5547 return error_mark_node; 5548 5549 if (processing_template_decl) 5550 { 5551 tree trait_expr = make_node (TRAIT_EXPR); 5552 TREE_TYPE (trait_expr) = boolean_type_node; 5553 TRAIT_EXPR_TYPE1 (trait_expr) = type1; 5554 TRAIT_EXPR_TYPE2 (trait_expr) = type2; 5555 TRAIT_EXPR_KIND (trait_expr) = kind; 5556 return trait_expr; 5557 } 5558 5559 switch (kind) 5560 { 5561 case CPTK_HAS_NOTHROW_ASSIGN: 5562 case CPTK_HAS_TRIVIAL_ASSIGN: 5563 case CPTK_HAS_NOTHROW_CONSTRUCTOR: 5564 case CPTK_HAS_TRIVIAL_CONSTRUCTOR: 5565 case CPTK_HAS_NOTHROW_COPY: 5566 case CPTK_HAS_TRIVIAL_COPY: 5567 case CPTK_HAS_TRIVIAL_DESTRUCTOR: 5568 case CPTK_HAS_VIRTUAL_DESTRUCTOR: 5569 case CPTK_IS_ABSTRACT: 5570 case CPTK_IS_EMPTY: 5571 case CPTK_IS_FINAL: 5572 case CPTK_IS_LITERAL_TYPE: 5573 case CPTK_IS_POD: 5574 case CPTK_IS_POLYMORPHIC: 5575 case CPTK_IS_STD_LAYOUT: 5576 case CPTK_IS_TRIVIAL: 5577 if (!check_trait_type (type1)) 5578 return error_mark_node; 5579 break; 5580 5581 case CPTK_IS_BASE_OF: 5582 if (NON_UNION_CLASS_TYPE_P (type1) && NON_UNION_CLASS_TYPE_P (type2) 5583 && !same_type_ignoring_top_level_qualifiers_p (type1, type2) 5584 && !complete_type_or_else (type2, NULL_TREE)) 5585 /* We already issued an error. */ 5586 return error_mark_node; 5587 break; 5588 5589 case CPTK_IS_CLASS: 5590 case CPTK_IS_ENUM: 5591 case CPTK_IS_UNION: 5592 break; 5593 5594 case CPTK_IS_CONVERTIBLE_TO: 5595 default: 5596 gcc_unreachable (); 5597 } 5598 5599 return (trait_expr_value (kind, type1, type2) 5600 ? boolean_true_node : boolean_false_node); 5601 } 5602 5603 /* Do-nothing variants of functions to handle pragma FLOAT_CONST_DECIMAL64, 5604 which is ignored for C++. */ 5605 5606 void 5607 set_float_const_decimal64 (void) 5608 { 5609 } 5610 5611 void 5612 clear_float_const_decimal64 (void) 5613 { 5614 } 5615 5616 bool 5617 float_const_decimal64_p (void) 5618 { 5619 return 0; 5620 } 5621 5622 5623 /* Return true if T is a literal type. */ 5624 5625 bool 5626 literal_type_p (tree t) 5627 { 5628 if (SCALAR_TYPE_P (t) 5629 || TREE_CODE (t) == REFERENCE_TYPE) 5630 return true; 5631 if (CLASS_TYPE_P (t)) 5632 { 5633 t = complete_type (t); 5634 gcc_assert (COMPLETE_TYPE_P (t) || errorcount); 5635 return CLASSTYPE_LITERAL_P (t); 5636 } 5637 if (TREE_CODE (t) == ARRAY_TYPE) 5638 return literal_type_p (strip_array_types (t)); 5639 return false; 5640 } 5641 5642 /* If DECL is a variable declared `constexpr', require its type 5643 be literal. Return the DECL if OK, otherwise NULL. */ 5644 5645 tree 5646 ensure_literal_type_for_constexpr_object (tree decl) 5647 { 5648 tree type = TREE_TYPE (decl); 5649 if (TREE_CODE (decl) == VAR_DECL && DECL_DECLARED_CONSTEXPR_P (decl) 5650 && !processing_template_decl) 5651 { 5652 if (CLASS_TYPE_P (type) && !COMPLETE_TYPE_P (complete_type (type))) 5653 /* Don't complain here, we'll complain about incompleteness 5654 when we try to initialize the variable. */; 5655 else if (!literal_type_p (type)) 5656 { 5657 error ("the type %qT of constexpr variable %qD is not literal", 5658 type, decl); 5659 explain_non_literal_class (type); 5660 return NULL; 5661 } 5662 } 5663 return decl; 5664 } 5665 5666 /* Representation of entries in the constexpr function definition table. */ 5667 5668 typedef struct GTY(()) constexpr_fundef { 5669 tree decl; 5670 tree body; 5671 } constexpr_fundef; 5672 5673 /* This table holds all constexpr function definitions seen in 5674 the current translation unit. */ 5675 5676 static GTY ((param_is (constexpr_fundef))) htab_t constexpr_fundef_table; 5677 5678 /* Utility function used for managing the constexpr function table. 5679 Return true if the entries pointed to by P and Q are for the 5680 same constexpr function. */ 5681 5682 static inline int 5683 constexpr_fundef_equal (const void *p, const void *q) 5684 { 5685 const constexpr_fundef *lhs = (const constexpr_fundef *) p; 5686 const constexpr_fundef *rhs = (const constexpr_fundef *) q; 5687 return lhs->decl == rhs->decl; 5688 } 5689 5690 /* Utility function used for managing the constexpr function table. 5691 Return a hash value for the entry pointed to by Q. */ 5692 5693 static inline hashval_t 5694 constexpr_fundef_hash (const void *p) 5695 { 5696 const constexpr_fundef *fundef = (const constexpr_fundef *) p; 5697 return DECL_UID (fundef->decl); 5698 } 5699 5700 /* Return a previously saved definition of function FUN. */ 5701 5702 static constexpr_fundef * 5703 retrieve_constexpr_fundef (tree fun) 5704 { 5705 constexpr_fundef fundef = { NULL, NULL }; 5706 if (constexpr_fundef_table == NULL) 5707 return NULL; 5708 5709 fundef.decl = fun; 5710 return (constexpr_fundef *) htab_find (constexpr_fundef_table, &fundef); 5711 } 5712 5713 /* Check whether the parameter and return types of FUN are valid for a 5714 constexpr function, and complain if COMPLAIN. */ 5715 5716 static bool 5717 is_valid_constexpr_fn (tree fun, bool complain) 5718 { 5719 tree parm = FUNCTION_FIRST_USER_PARM (fun); 5720 bool ret = true; 5721 for (; parm != NULL; parm = TREE_CHAIN (parm)) 5722 if (!literal_type_p (TREE_TYPE (parm))) 5723 { 5724 ret = false; 5725 if (complain) 5726 { 5727 error ("invalid type for parameter %d of constexpr " 5728 "function %q+#D", DECL_PARM_INDEX (parm), fun); 5729 explain_non_literal_class (TREE_TYPE (parm)); 5730 } 5731 } 5732 5733 if (!DECL_CONSTRUCTOR_P (fun)) 5734 { 5735 tree rettype = TREE_TYPE (TREE_TYPE (fun)); 5736 if (!literal_type_p (rettype)) 5737 { 5738 ret = false; 5739 if (complain) 5740 { 5741 error ("invalid return type %qT of constexpr function %q+D", 5742 rettype, fun); 5743 explain_non_literal_class (rettype); 5744 } 5745 } 5746 5747 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fun) 5748 && !CLASSTYPE_LITERAL_P (DECL_CONTEXT (fun))) 5749 { 5750 ret = false; 5751 if (complain) 5752 { 5753 error ("enclosing class of constexpr non-static member " 5754 "function %q+#D is not a literal type", fun); 5755 explain_non_literal_class (DECL_CONTEXT (fun)); 5756 } 5757 } 5758 } 5759 else if (CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fun))) 5760 { 5761 ret = false; 5762 if (complain) 5763 error ("%q#T has virtual base classes", DECL_CONTEXT (fun)); 5764 } 5765 5766 return ret; 5767 } 5768 5769 /* Subroutine of build_constexpr_constructor_member_initializers. 5770 The expression tree T represents a data member initialization 5771 in a (constexpr) constructor definition. Build a pairing of 5772 the data member with its initializer, and prepend that pair 5773 to the existing initialization pair INITS. */ 5774 5775 static bool 5776 build_data_member_initialization (tree t, VEC(constructor_elt,gc) **vec) 5777 { 5778 tree member, init; 5779 if (TREE_CODE (t) == CLEANUP_POINT_EXPR) 5780 t = TREE_OPERAND (t, 0); 5781 if (TREE_CODE (t) == EXPR_STMT) 5782 t = TREE_OPERAND (t, 0); 5783 if (t == error_mark_node) 5784 return false; 5785 if (TREE_CODE (t) == STATEMENT_LIST) 5786 { 5787 tree_stmt_iterator i; 5788 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i)) 5789 { 5790 if (! build_data_member_initialization (tsi_stmt (i), vec)) 5791 return false; 5792 } 5793 return true; 5794 } 5795 if (TREE_CODE (t) == CLEANUP_STMT) 5796 { 5797 /* We can't see a CLEANUP_STMT in a constructor for a literal class, 5798 but we can in a constexpr constructor for a non-literal class. Just 5799 ignore it; either all the initialization will be constant, in which 5800 case the cleanup can't run, or it can't be constexpr. 5801 Still recurse into CLEANUP_BODY. */ 5802 return build_data_member_initialization (CLEANUP_BODY (t), vec); 5803 } 5804 if (TREE_CODE (t) == CONVERT_EXPR) 5805 t = TREE_OPERAND (t, 0); 5806 if (TREE_CODE (t) == INIT_EXPR 5807 || TREE_CODE (t) == MODIFY_EXPR) 5808 { 5809 member = TREE_OPERAND (t, 0); 5810 init = unshare_expr (TREE_OPERAND (t, 1)); 5811 } 5812 else if (TREE_CODE (t) == CALL_EXPR) 5813 { 5814 member = CALL_EXPR_ARG (t, 0); 5815 /* We don't use build_cplus_new here because it complains about 5816 abstract bases. Leaving the call unwrapped means that it has the 5817 wrong type, but cxx_eval_constant_expression doesn't care. */ 5818 init = unshare_expr (t); 5819 } 5820 else if (TREE_CODE (t) == DECL_EXPR) 5821 /* Declaring a temporary, don't add it to the CONSTRUCTOR. */ 5822 return true; 5823 else 5824 gcc_unreachable (); 5825 if (TREE_CODE (member) == INDIRECT_REF) 5826 member = TREE_OPERAND (member, 0); 5827 if (TREE_CODE (member) == NOP_EXPR) 5828 { 5829 tree op = member; 5830 STRIP_NOPS (op); 5831 if (TREE_CODE (op) == ADDR_EXPR) 5832 { 5833 gcc_assert (same_type_ignoring_top_level_qualifiers_p 5834 (TREE_TYPE (TREE_TYPE (op)), 5835 TREE_TYPE (TREE_TYPE (member)))); 5836 /* Initializing a cv-qualified member; we need to look through 5837 the const_cast. */ 5838 member = op; 5839 } 5840 else if (op == current_class_ptr 5841 && (same_type_ignoring_top_level_qualifiers_p 5842 (TREE_TYPE (TREE_TYPE (member)), 5843 current_class_type))) 5844 /* Delegating constructor. */ 5845 member = op; 5846 else 5847 { 5848 /* This is an initializer for an empty base; keep it for now so 5849 we can check it in cxx_eval_bare_aggregate. */ 5850 gcc_assert (is_empty_class (TREE_TYPE (TREE_TYPE (member)))); 5851 } 5852 } 5853 if (TREE_CODE (member) == ADDR_EXPR) 5854 member = TREE_OPERAND (member, 0); 5855 if (TREE_CODE (member) == COMPONENT_REF 5856 /* If we're initializing a member of a subaggregate, it's a vtable 5857 pointer. Leave it as COMPONENT_REF so we remember the path to get 5858 to the vfield. */ 5859 && TREE_CODE (TREE_OPERAND (member, 0)) != COMPONENT_REF) 5860 member = TREE_OPERAND (member, 1); 5861 CONSTRUCTOR_APPEND_ELT (*vec, member, init); 5862 return true; 5863 } 5864 5865 /* Make sure that there are no statements after LAST in the constructor 5866 body represented by LIST. */ 5867 5868 bool 5869 check_constexpr_ctor_body (tree last, tree list) 5870 { 5871 bool ok = true; 5872 if (TREE_CODE (list) == STATEMENT_LIST) 5873 { 5874 tree_stmt_iterator i = tsi_last (list); 5875 for (; !tsi_end_p (i); tsi_prev (&i)) 5876 { 5877 tree t = tsi_stmt (i); 5878 if (t == last) 5879 break; 5880 if (TREE_CODE (t) == BIND_EXPR) 5881 { 5882 if (!check_constexpr_ctor_body (last, BIND_EXPR_BODY (t))) 5883 return false; 5884 else 5885 continue; 5886 } 5887 /* We currently allow typedefs and static_assert. 5888 FIXME allow them in the standard, too. */ 5889 if (TREE_CODE (t) != STATIC_ASSERT) 5890 { 5891 ok = false; 5892 break; 5893 } 5894 } 5895 } 5896 else if (list != last 5897 && TREE_CODE (list) != STATIC_ASSERT) 5898 ok = false; 5899 if (!ok) 5900 { 5901 error ("constexpr constructor does not have empty body"); 5902 DECL_DECLARED_CONSTEXPR_P (current_function_decl) = false; 5903 } 5904 return ok; 5905 } 5906 5907 /* VEC is a vector of constructor elements built up for the base and member 5908 initializers of a constructor for TYPE. They need to be in increasing 5909 offset order, which they might not be yet if TYPE has a primary base 5910 which is not first in the base-clause or a vptr and at least one base 5911 all of which are non-primary. */ 5912 5913 static VEC(constructor_elt,gc) * 5914 sort_constexpr_mem_initializers (tree type, VEC(constructor_elt,gc) *vec) 5915 { 5916 tree pri = CLASSTYPE_PRIMARY_BINFO (type); 5917 tree field_type; 5918 constructor_elt elt; 5919 int i; 5920 5921 if (pri) 5922 field_type = BINFO_TYPE (pri); 5923 else if (TYPE_CONTAINS_VPTR_P (type)) 5924 field_type = vtbl_ptr_type_node; 5925 else 5926 return vec; 5927 5928 /* Find the element for the primary base or vptr and move it to the 5929 beginning of the vec. */ 5930 for (i = 0; ; ++i) 5931 if (TREE_TYPE (VEC_index (constructor_elt, vec, i)->index) == field_type) 5932 break; 5933 5934 if (i > 0) 5935 { 5936 elt = *VEC_index (constructor_elt, vec, i); 5937 for (; i > 0; --i) 5938 VEC_replace (constructor_elt, vec, i, 5939 VEC_index (constructor_elt, vec, i-1)); 5940 VEC_replace (constructor_elt, vec, 0, &elt); 5941 } 5942 return vec; 5943 } 5944 5945 /* Build compile-time evalable representations of member-initializer list 5946 for a constexpr constructor. */ 5947 5948 static tree 5949 build_constexpr_constructor_member_initializers (tree type, tree body) 5950 { 5951 VEC(constructor_elt,gc) *vec = NULL; 5952 bool ok = true; 5953 if (TREE_CODE (body) == MUST_NOT_THROW_EXPR 5954 || TREE_CODE (body) == EH_SPEC_BLOCK) 5955 body = TREE_OPERAND (body, 0); 5956 if (TREE_CODE (body) == STATEMENT_LIST) 5957 body = STATEMENT_LIST_HEAD (body)->stmt; 5958 body = BIND_EXPR_BODY (body); 5959 if (TREE_CODE (body) == CLEANUP_POINT_EXPR) 5960 { 5961 body = TREE_OPERAND (body, 0); 5962 if (TREE_CODE (body) == EXPR_STMT) 5963 body = TREE_OPERAND (body, 0); 5964 if (TREE_CODE (body) == INIT_EXPR 5965 && (same_type_ignoring_top_level_qualifiers_p 5966 (TREE_TYPE (TREE_OPERAND (body, 0)), 5967 current_class_type))) 5968 { 5969 /* Trivial copy. */ 5970 return TREE_OPERAND (body, 1); 5971 } 5972 ok = build_data_member_initialization (body, &vec); 5973 } 5974 else if (TREE_CODE (body) == STATEMENT_LIST) 5975 { 5976 tree_stmt_iterator i; 5977 for (i = tsi_start (body); !tsi_end_p (i); tsi_next (&i)) 5978 { 5979 ok = build_data_member_initialization (tsi_stmt (i), &vec); 5980 if (!ok) 5981 break; 5982 } 5983 } 5984 else if (EXPR_P (body)) 5985 ok = build_data_member_initialization (body, &vec); 5986 else 5987 gcc_assert (errorcount > 0); 5988 if (ok) 5989 { 5990 if (VEC_length (constructor_elt, vec) > 0) 5991 { 5992 /* In a delegating constructor, return the target. */ 5993 constructor_elt *ce = VEC_index (constructor_elt, vec, 0); 5994 if (ce->index == current_class_ptr) 5995 { 5996 body = ce->value; 5997 VEC_free (constructor_elt, gc, vec); 5998 return body; 5999 } 6000 } 6001 vec = sort_constexpr_mem_initializers (type, vec); 6002 return build_constructor (type, vec); 6003 } 6004 else 6005 return error_mark_node; 6006 } 6007 6008 /* Subroutine of register_constexpr_fundef. BODY is the body of a function 6009 declared to be constexpr, or a sub-statement thereof. Returns the 6010 return value if suitable, error_mark_node for a statement not allowed in 6011 a constexpr function, or NULL_TREE if no return value was found. */ 6012 6013 static tree 6014 constexpr_fn_retval (tree body) 6015 { 6016 switch (TREE_CODE (body)) 6017 { 6018 case STATEMENT_LIST: 6019 { 6020 tree_stmt_iterator i; 6021 tree expr = NULL_TREE; 6022 for (i = tsi_start (body); !tsi_end_p (i); tsi_next (&i)) 6023 { 6024 tree s = constexpr_fn_retval (tsi_stmt (i)); 6025 if (s == error_mark_node) 6026 return error_mark_node; 6027 else if (s == NULL_TREE) 6028 /* Keep iterating. */; 6029 else if (expr) 6030 /* Multiple return statements. */ 6031 return error_mark_node; 6032 else 6033 expr = s; 6034 } 6035 return expr; 6036 } 6037 6038 case RETURN_EXPR: 6039 return unshare_expr (TREE_OPERAND (body, 0)); 6040 6041 case DECL_EXPR: 6042 if (TREE_CODE (DECL_EXPR_DECL (body)) == USING_DECL) 6043 return NULL_TREE; 6044 return error_mark_node; 6045 6046 case CLEANUP_POINT_EXPR: 6047 return constexpr_fn_retval (TREE_OPERAND (body, 0)); 6048 6049 case USING_STMT: 6050 return NULL_TREE; 6051 6052 default: 6053 return error_mark_node; 6054 } 6055 } 6056 6057 /* Subroutine of register_constexpr_fundef. BODY is the DECL_SAVED_TREE of 6058 FUN; do the necessary transformations to turn it into a single expression 6059 that we can store in the hash table. */ 6060 6061 static tree 6062 massage_constexpr_body (tree fun, tree body) 6063 { 6064 if (DECL_CONSTRUCTOR_P (fun)) 6065 body = build_constexpr_constructor_member_initializers 6066 (DECL_CONTEXT (fun), body); 6067 else 6068 { 6069 if (TREE_CODE (body) == EH_SPEC_BLOCK) 6070 body = EH_SPEC_STMTS (body); 6071 if (TREE_CODE (body) == MUST_NOT_THROW_EXPR) 6072 body = TREE_OPERAND (body, 0); 6073 if (TREE_CODE (body) == BIND_EXPR) 6074 body = BIND_EXPR_BODY (body); 6075 body = constexpr_fn_retval (body); 6076 } 6077 return body; 6078 } 6079 6080 /* FUN is a constexpr constructor with massaged body BODY. Return true 6081 if some bases/fields are uninitialized, and complain if COMPLAIN. */ 6082 6083 static bool 6084 cx_check_missing_mem_inits (tree fun, tree body, bool complain) 6085 { 6086 bool bad; 6087 tree field; 6088 unsigned i, nelts; 6089 tree ctype; 6090 6091 if (TREE_CODE (body) != CONSTRUCTOR) 6092 return false; 6093 6094 nelts = CONSTRUCTOR_NELTS (body); 6095 ctype = DECL_CONTEXT (fun); 6096 field = TYPE_FIELDS (ctype); 6097 6098 if (TREE_CODE (ctype) == UNION_TYPE) 6099 { 6100 if (nelts == 0 && next_initializable_field (field)) 6101 { 6102 if (complain) 6103 error ("%<constexpr%> constructor for union %qT must " 6104 "initialize exactly one non-static data member", ctype); 6105 return true; 6106 } 6107 return false; 6108 } 6109 6110 bad = false; 6111 for (i = 0; i <= nelts; ++i) 6112 { 6113 tree index; 6114 if (i == nelts) 6115 index = NULL_TREE; 6116 else 6117 { 6118 index = CONSTRUCTOR_ELT (body, i)->index; 6119 /* Skip base and vtable inits. */ 6120 if (TREE_CODE (index) != FIELD_DECL 6121 || DECL_ARTIFICIAL (index)) 6122 continue; 6123 } 6124 for (; field != index; field = DECL_CHAIN (field)) 6125 { 6126 tree ftype; 6127 if (TREE_CODE (field) != FIELD_DECL 6128 || (DECL_C_BIT_FIELD (field) && !DECL_NAME (field)) 6129 || DECL_ARTIFICIAL (field)) 6130 continue; 6131 ftype = strip_array_types (TREE_TYPE (field)); 6132 if (type_has_constexpr_default_constructor (ftype)) 6133 { 6134 /* It's OK to skip a member with a trivial constexpr ctor. 6135 A constexpr ctor that isn't trivial should have been 6136 added in by now. */ 6137 gcc_checking_assert (!TYPE_HAS_COMPLEX_DFLT (ftype) 6138 || errorcount != 0); 6139 continue; 6140 } 6141 if (!complain) 6142 return true; 6143 error ("uninitialized member %qD in %<constexpr%> constructor", 6144 field); 6145 bad = true; 6146 } 6147 if (field == NULL_TREE) 6148 break; 6149 field = DECL_CHAIN (field); 6150 } 6151 6152 return bad; 6153 } 6154 6155 /* We are processing the definition of the constexpr function FUN. 6156 Check that its BODY fulfills the propriate requirements and 6157 enter it in the constexpr function definition table. 6158 For constructor BODY is actually the TREE_LIST of the 6159 member-initializer list. */ 6160 6161 tree 6162 register_constexpr_fundef (tree fun, tree body) 6163 { 6164 constexpr_fundef entry; 6165 constexpr_fundef **slot; 6166 6167 if (!is_valid_constexpr_fn (fun, !DECL_GENERATED_P (fun))) 6168 return NULL; 6169 6170 body = massage_constexpr_body (fun, body); 6171 if (body == NULL_TREE || body == error_mark_node) 6172 { 6173 if (!DECL_CONSTRUCTOR_P (fun)) 6174 error ("body of constexpr function %qD not a return-statement", fun); 6175 return NULL; 6176 } 6177 6178 if (!potential_rvalue_constant_expression (body)) 6179 { 6180 if (!DECL_GENERATED_P (fun)) 6181 require_potential_rvalue_constant_expression (body); 6182 return NULL; 6183 } 6184 6185 if (DECL_CONSTRUCTOR_P (fun) 6186 && cx_check_missing_mem_inits (fun, body, !DECL_GENERATED_P (fun))) 6187 return NULL; 6188 6189 /* Create the constexpr function table if necessary. */ 6190 if (constexpr_fundef_table == NULL) 6191 constexpr_fundef_table = htab_create_ggc (101, 6192 constexpr_fundef_hash, 6193 constexpr_fundef_equal, 6194 ggc_free); 6195 entry.decl = fun; 6196 entry.body = body; 6197 slot = (constexpr_fundef **) 6198 htab_find_slot (constexpr_fundef_table, &entry, INSERT); 6199 6200 gcc_assert (*slot == NULL); 6201 *slot = ggc_alloc_constexpr_fundef (); 6202 **slot = entry; 6203 6204 return fun; 6205 } 6206 6207 /* FUN is a non-constexpr function called in a context that requires a 6208 constant expression. If it comes from a constexpr template, explain why 6209 the instantiation isn't constexpr. */ 6210 6211 void 6212 explain_invalid_constexpr_fn (tree fun) 6213 { 6214 static struct pointer_set_t *diagnosed; 6215 tree body; 6216 location_t save_loc; 6217 /* Only diagnose defaulted functions or instantiations. */ 6218 if (!DECL_DEFAULTED_FN (fun) 6219 && !is_instantiation_of_constexpr (fun)) 6220 return; 6221 if (diagnosed == NULL) 6222 diagnosed = pointer_set_create (); 6223 if (pointer_set_insert (diagnosed, fun) != 0) 6224 /* Already explained. */ 6225 return; 6226 6227 save_loc = input_location; 6228 input_location = DECL_SOURCE_LOCATION (fun); 6229 inform (0, "%q+D is not usable as a constexpr function because:", fun); 6230 /* First check the declaration. */ 6231 if (is_valid_constexpr_fn (fun, true)) 6232 { 6233 /* Then if it's OK, the body. */ 6234 if (DECL_DEFAULTED_FN (fun)) 6235 explain_implicit_non_constexpr (fun); 6236 else 6237 { 6238 body = massage_constexpr_body (fun, DECL_SAVED_TREE (fun)); 6239 require_potential_rvalue_constant_expression (body); 6240 if (DECL_CONSTRUCTOR_P (fun)) 6241 cx_check_missing_mem_inits (fun, body, true); 6242 } 6243 } 6244 input_location = save_loc; 6245 } 6246 6247 /* Objects of this type represent calls to constexpr functions 6248 along with the bindings of parameters to their arguments, for 6249 the purpose of compile time evaluation. */ 6250 6251 typedef struct GTY(()) constexpr_call { 6252 /* Description of the constexpr function definition. */ 6253 constexpr_fundef *fundef; 6254 /* Parameter bindings enironment. A TREE_LIST where each TREE_PURPOSE 6255 is a parameter _DECL and the TREE_VALUE is the value of the parameter. 6256 Note: This arrangement is made to accomodate the use of 6257 iterative_hash_template_arg (see pt.c). If you change this 6258 representation, also change the hash calculation in 6259 cxx_eval_call_expression. */ 6260 tree bindings; 6261 /* Result of the call. 6262 NULL means the call is being evaluated. 6263 error_mark_node means that the evaluation was erroneous; 6264 otherwise, the actuall value of the call. */ 6265 tree result; 6266 /* The hash of this call; we remember it here to avoid having to 6267 recalculate it when expanding the hash table. */ 6268 hashval_t hash; 6269 } constexpr_call; 6270 6271 /* A table of all constexpr calls that have been evaluated by the 6272 compiler in this translation unit. */ 6273 6274 static GTY ((param_is (constexpr_call))) htab_t constexpr_call_table; 6275 6276 static tree cxx_eval_constant_expression (const constexpr_call *, tree, 6277 bool, bool, bool *); 6278 6279 /* Compute a hash value for a constexpr call representation. */ 6280 6281 static hashval_t 6282 constexpr_call_hash (const void *p) 6283 { 6284 const constexpr_call *info = (const constexpr_call *) p; 6285 return info->hash; 6286 } 6287 6288 /* Return 1 if the objects pointed to by P and Q represent calls 6289 to the same constexpr function with the same arguments. 6290 Otherwise, return 0. */ 6291 6292 static int 6293 constexpr_call_equal (const void *p, const void *q) 6294 { 6295 const constexpr_call *lhs = (const constexpr_call *) p; 6296 const constexpr_call *rhs = (const constexpr_call *) q; 6297 tree lhs_bindings; 6298 tree rhs_bindings; 6299 if (lhs == rhs) 6300 return 1; 6301 if (!constexpr_fundef_equal (lhs->fundef, rhs->fundef)) 6302 return 0; 6303 lhs_bindings = lhs->bindings; 6304 rhs_bindings = rhs->bindings; 6305 while (lhs_bindings != NULL && rhs_bindings != NULL) 6306 { 6307 tree lhs_arg = TREE_VALUE (lhs_bindings); 6308 tree rhs_arg = TREE_VALUE (rhs_bindings); 6309 gcc_assert (TREE_TYPE (lhs_arg) == TREE_TYPE (rhs_arg)); 6310 if (!cp_tree_equal (lhs_arg, rhs_arg)) 6311 return 0; 6312 lhs_bindings = TREE_CHAIN (lhs_bindings); 6313 rhs_bindings = TREE_CHAIN (rhs_bindings); 6314 } 6315 return lhs_bindings == rhs_bindings; 6316 } 6317 6318 /* Initialize the constexpr call table, if needed. */ 6319 6320 static void 6321 maybe_initialize_constexpr_call_table (void) 6322 { 6323 if (constexpr_call_table == NULL) 6324 constexpr_call_table = htab_create_ggc (101, 6325 constexpr_call_hash, 6326 constexpr_call_equal, 6327 ggc_free); 6328 } 6329 6330 /* Return true if T designates the implied `this' parameter. */ 6331 6332 static inline bool 6333 is_this_parameter (tree t) 6334 { 6335 return t == current_class_ptr; 6336 } 6337 6338 /* We have an expression tree T that represents a call, either CALL_EXPR 6339 or AGGR_INIT_EXPR. If the call is lexically to a named function, 6340 retrun the _DECL for that function. */ 6341 6342 static tree 6343 get_function_named_in_call (tree t) 6344 { 6345 tree fun = NULL; 6346 switch (TREE_CODE (t)) 6347 { 6348 case CALL_EXPR: 6349 fun = CALL_EXPR_FN (t); 6350 break; 6351 6352 case AGGR_INIT_EXPR: 6353 fun = AGGR_INIT_EXPR_FN (t); 6354 break; 6355 6356 default: 6357 gcc_unreachable(); 6358 break; 6359 } 6360 if (TREE_CODE (fun) == ADDR_EXPR 6361 && TREE_CODE (TREE_OPERAND (fun, 0)) == FUNCTION_DECL) 6362 fun = TREE_OPERAND (fun, 0); 6363 return fun; 6364 } 6365 6366 /* We have an expression tree T that represents a call, either CALL_EXPR 6367 or AGGR_INIT_EXPR. Return the Nth argument. */ 6368 6369 static inline tree 6370 get_nth_callarg (tree t, int n) 6371 { 6372 switch (TREE_CODE (t)) 6373 { 6374 case CALL_EXPR: 6375 return CALL_EXPR_ARG (t, n); 6376 6377 case AGGR_INIT_EXPR: 6378 return AGGR_INIT_EXPR_ARG (t, n); 6379 6380 default: 6381 gcc_unreachable (); 6382 return NULL; 6383 } 6384 } 6385 6386 /* Look up the binding of the function parameter T in a constexpr 6387 function call context CALL. */ 6388 6389 static tree 6390 lookup_parameter_binding (const constexpr_call *call, tree t) 6391 { 6392 tree b = purpose_member (t, call->bindings); 6393 return TREE_VALUE (b); 6394 } 6395 6396 /* Attempt to evaluate T which represents a call to a builtin function. 6397 We assume here that all builtin functions evaluate to scalar types 6398 represented by _CST nodes. */ 6399 6400 static tree 6401 cxx_eval_builtin_function_call (const constexpr_call *call, tree t, 6402 bool allow_non_constant, bool addr, 6403 bool *non_constant_p) 6404 { 6405 const int nargs = call_expr_nargs (t); 6406 tree *args = (tree *) alloca (nargs * sizeof (tree)); 6407 tree new_call; 6408 int i; 6409 for (i = 0; i < nargs; ++i) 6410 { 6411 args[i] = cxx_eval_constant_expression (call, CALL_EXPR_ARG (t, i), 6412 allow_non_constant, addr, 6413 non_constant_p); 6414 if (allow_non_constant && *non_constant_p) 6415 return t; 6416 } 6417 if (*non_constant_p) 6418 return t; 6419 new_call = build_call_array_loc (EXPR_LOCATION (t), TREE_TYPE (t), 6420 CALL_EXPR_FN (t), nargs, args); 6421 return fold (new_call); 6422 } 6423 6424 /* TEMP is the constant value of a temporary object of type TYPE. Adjust 6425 the type of the value to match. */ 6426 6427 static tree 6428 adjust_temp_type (tree type, tree temp) 6429 { 6430 if (TREE_TYPE (temp) == type) 6431 return temp; 6432 /* Avoid wrapping an aggregate value in a NOP_EXPR. */ 6433 if (TREE_CODE (temp) == CONSTRUCTOR) 6434 return build_constructor (type, CONSTRUCTOR_ELTS (temp)); 6435 gcc_assert (SCALAR_TYPE_P (type)); 6436 return cp_fold_convert (type, temp); 6437 } 6438 6439 /* Subroutine of cxx_eval_call_expression. 6440 We are processing a call expression (either CALL_EXPR or 6441 AGGR_INIT_EXPR) in the call context of OLD_CALL. Evaluate 6442 all arguments and bind their values to correspondings 6443 parameters, making up the NEW_CALL context. */ 6444 6445 static void 6446 cxx_bind_parameters_in_call (const constexpr_call *old_call, tree t, 6447 constexpr_call *new_call, 6448 bool allow_non_constant, 6449 bool *non_constant_p) 6450 { 6451 const int nargs = call_expr_nargs (t); 6452 tree fun = new_call->fundef->decl; 6453 tree parms = DECL_ARGUMENTS (fun); 6454 int i; 6455 for (i = 0; i < nargs; ++i) 6456 { 6457 tree x, arg; 6458 tree type = parms ? TREE_TYPE (parms) : void_type_node; 6459 /* For member function, the first argument is a pointer to the implied 6460 object. And for an object contruction, don't bind `this' before 6461 it is fully constructed. */ 6462 if (i == 0 && DECL_CONSTRUCTOR_P (fun)) 6463 goto next; 6464 x = get_nth_callarg (t, i); 6465 arg = cxx_eval_constant_expression (old_call, x, allow_non_constant, 6466 TREE_CODE (type) == REFERENCE_TYPE, 6467 non_constant_p); 6468 /* Don't VERIFY_CONSTANT here. */ 6469 if (*non_constant_p && allow_non_constant) 6470 return; 6471 /* Just discard ellipsis args after checking their constantitude. */ 6472 if (!parms) 6473 continue; 6474 if (*non_constant_p) 6475 /* Don't try to adjust the type of non-constant args. */ 6476 goto next; 6477 6478 /* Make sure the binding has the same type as the parm. */ 6479 if (TREE_CODE (type) != REFERENCE_TYPE) 6480 arg = adjust_temp_type (type, arg); 6481 new_call->bindings = tree_cons (parms, arg, new_call->bindings); 6482 next: 6483 parms = TREE_CHAIN (parms); 6484 } 6485 } 6486 6487 /* Variables and functions to manage constexpr call expansion context. 6488 These do not need to be marked for PCH or GC. */ 6489 6490 /* FIXME remember and print actual constant arguments. */ 6491 static VEC(tree,heap) *call_stack = NULL; 6492 static int call_stack_tick; 6493 static int last_cx_error_tick; 6494 6495 static bool 6496 push_cx_call_context (tree call) 6497 { 6498 ++call_stack_tick; 6499 if (!EXPR_HAS_LOCATION (call)) 6500 SET_EXPR_LOCATION (call, input_location); 6501 VEC_safe_push (tree, heap, call_stack, call); 6502 if (VEC_length (tree, call_stack) > (unsigned) max_constexpr_depth) 6503 return false; 6504 return true; 6505 } 6506 6507 static void 6508 pop_cx_call_context (void) 6509 { 6510 ++call_stack_tick; 6511 VEC_pop (tree, call_stack); 6512 } 6513 6514 VEC(tree,heap) * 6515 cx_error_context (void) 6516 { 6517 VEC(tree,heap) *r = NULL; 6518 if (call_stack_tick != last_cx_error_tick 6519 && !VEC_empty (tree, call_stack)) 6520 r = call_stack; 6521 last_cx_error_tick = call_stack_tick; 6522 return r; 6523 } 6524 6525 /* Subroutine of cxx_eval_constant_expression. 6526 Evaluate the call expression tree T in the context of OLD_CALL expression 6527 evaluation. */ 6528 6529 static tree 6530 cxx_eval_call_expression (const constexpr_call *old_call, tree t, 6531 bool allow_non_constant, bool addr, 6532 bool *non_constant_p) 6533 { 6534 location_t loc = EXPR_LOC_OR_HERE (t); 6535 tree fun = get_function_named_in_call (t); 6536 tree result; 6537 constexpr_call new_call = { NULL, NULL, NULL, 0 }; 6538 constexpr_call **slot; 6539 constexpr_call *entry; 6540 bool depth_ok; 6541 6542 if (TREE_CODE (fun) != FUNCTION_DECL) 6543 { 6544 /* Might be a constexpr function pointer. */ 6545 fun = cxx_eval_constant_expression (old_call, fun, allow_non_constant, 6546 /*addr*/false, non_constant_p); 6547 if (TREE_CODE (fun) == ADDR_EXPR) 6548 fun = TREE_OPERAND (fun, 0); 6549 } 6550 if (TREE_CODE (fun) != FUNCTION_DECL) 6551 { 6552 if (!allow_non_constant && !*non_constant_p) 6553 error_at (loc, "expression %qE does not designate a constexpr " 6554 "function", fun); 6555 *non_constant_p = true; 6556 return t; 6557 } 6558 if (DECL_CLONED_FUNCTION_P (fun)) 6559 fun = DECL_CLONED_FUNCTION (fun); 6560 if (is_builtin_fn (fun)) 6561 return cxx_eval_builtin_function_call (old_call, t, allow_non_constant, 6562 addr, non_constant_p); 6563 if (!DECL_DECLARED_CONSTEXPR_P (fun)) 6564 { 6565 if (!allow_non_constant) 6566 { 6567 error_at (loc, "call to non-constexpr function %qD", fun); 6568 explain_invalid_constexpr_fn (fun); 6569 } 6570 *non_constant_p = true; 6571 return t; 6572 } 6573 6574 /* Shortcut trivial copy constructor/op=. */ 6575 if (call_expr_nargs (t) == 2 && trivial_fn_p (fun)) 6576 { 6577 tree arg = convert_from_reference (get_nth_callarg (t, 1)); 6578 return cxx_eval_constant_expression (old_call, arg, allow_non_constant, 6579 addr, non_constant_p); 6580 } 6581 6582 /* If in direct recursive call, optimize definition search. */ 6583 if (old_call != NULL && old_call->fundef->decl == fun) 6584 new_call.fundef = old_call->fundef; 6585 else 6586 { 6587 new_call.fundef = retrieve_constexpr_fundef (fun); 6588 if (new_call.fundef == NULL || new_call.fundef->body == NULL) 6589 { 6590 if (!allow_non_constant) 6591 { 6592 if (DECL_INITIAL (fun)) 6593 { 6594 /* The definition of fun was somehow unsuitable. */ 6595 error_at (loc, "%qD called in a constant expression", fun); 6596 explain_invalid_constexpr_fn (fun); 6597 } 6598 else 6599 error_at (loc, "%qD used before its definition", fun); 6600 } 6601 *non_constant_p = true; 6602 return t; 6603 } 6604 } 6605 cxx_bind_parameters_in_call (old_call, t, &new_call, 6606 allow_non_constant, non_constant_p); 6607 if (*non_constant_p) 6608 return t; 6609 6610 depth_ok = push_cx_call_context (t); 6611 6612 new_call.hash 6613 = iterative_hash_template_arg (new_call.bindings, 6614 constexpr_fundef_hash (new_call.fundef)); 6615 6616 /* If we have seen this call before, we are done. */ 6617 maybe_initialize_constexpr_call_table (); 6618 slot = (constexpr_call **) 6619 htab_find_slot (constexpr_call_table, &new_call, INSERT); 6620 entry = *slot; 6621 if (entry == NULL) 6622 { 6623 /* We need to keep a pointer to the entry, not just the slot, as the 6624 slot can move in the call to cxx_eval_builtin_function_call. */ 6625 *slot = entry = ggc_alloc_constexpr_call (); 6626 *entry = new_call; 6627 } 6628 /* Calls which are in progress have their result set to NULL 6629 so that we can detect circular dependencies. */ 6630 else if (entry->result == NULL) 6631 { 6632 if (!allow_non_constant) 6633 error ("call has circular dependency"); 6634 *non_constant_p = true; 6635 entry->result = result = error_mark_node; 6636 } 6637 6638 if (!depth_ok) 6639 { 6640 if (!allow_non_constant) 6641 error ("constexpr evaluation depth exceeds maximum of %d (use " 6642 "-fconstexpr-depth= to increase the maximum)", 6643 max_constexpr_depth); 6644 *non_constant_p = true; 6645 entry->result = result = error_mark_node; 6646 } 6647 else 6648 { 6649 result = entry->result; 6650 if (!result || result == error_mark_node) 6651 result = (cxx_eval_constant_expression 6652 (&new_call, new_call.fundef->body, 6653 allow_non_constant, addr, 6654 non_constant_p)); 6655 if (result == error_mark_node) 6656 *non_constant_p = true; 6657 if (*non_constant_p) 6658 entry->result = result = error_mark_node; 6659 else 6660 { 6661 /* If this was a call to initialize an object, set the type of 6662 the CONSTRUCTOR to the type of that object. */ 6663 if (DECL_CONSTRUCTOR_P (fun)) 6664 { 6665 tree ob_arg = get_nth_callarg (t, 0); 6666 STRIP_NOPS (ob_arg); 6667 gcc_assert (TREE_CODE (TREE_TYPE (ob_arg)) == POINTER_TYPE 6668 && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (ob_arg)))); 6669 result = adjust_temp_type (TREE_TYPE (TREE_TYPE (ob_arg)), 6670 result); 6671 } 6672 entry->result = result; 6673 } 6674 } 6675 6676 pop_cx_call_context (); 6677 return unshare_expr (result); 6678 } 6679 6680 /* FIXME speed this up, it's taking 16% of compile time on sieve testcase. */ 6681 6682 bool 6683 reduced_constant_expression_p (tree t) 6684 { 6685 if (TREE_OVERFLOW_P (t)) 6686 /* Integer overflow makes this not a constant expression. */ 6687 return false; 6688 /* FIXME are we calling this too much? */ 6689 return initializer_constant_valid_p (t, TREE_TYPE (t)) != NULL_TREE; 6690 } 6691 6692 /* Some expressions may have constant operands but are not constant 6693 themselves, such as 1/0. Call this function (or rather, the macro 6694 following it) to check for that condition. 6695 6696 We only call this in places that require an arithmetic constant, not in 6697 places where we might have a non-constant expression that can be a 6698 component of a constant expression, such as the address of a constexpr 6699 variable that might be dereferenced later. */ 6700 6701 static bool 6702 verify_constant (tree t, bool allow_non_constant, bool *non_constant_p) 6703 { 6704 if (!*non_constant_p && !reduced_constant_expression_p (t)) 6705 { 6706 if (!allow_non_constant) 6707 { 6708 /* If T was already folded to a _CST with TREE_OVERFLOW set, 6709 printing the folded constant isn't helpful. */ 6710 if (TREE_OVERFLOW_P (t)) 6711 { 6712 permerror (input_location, "overflow in constant expression"); 6713 /* If we're being permissive (and are in an enforcing 6714 context), consider this constant. */ 6715 if (flag_permissive) 6716 return false; 6717 } 6718 else 6719 error ("%q+E is not a constant expression", t); 6720 } 6721 *non_constant_p = true; 6722 } 6723 return *non_constant_p; 6724 } 6725 #define VERIFY_CONSTANT(X) \ 6726 do { \ 6727 if (verify_constant ((X), allow_non_constant, non_constant_p)) \ 6728 return t; \ 6729 } while (0) 6730 6731 /* Subroutine of cxx_eval_constant_expression. 6732 Attempt to reduce the unary expression tree T to a compile time value. 6733 If successful, return the value. Otherwise issue a diagnostic 6734 and return error_mark_node. */ 6735 6736 static tree 6737 cxx_eval_unary_expression (const constexpr_call *call, tree t, 6738 bool allow_non_constant, bool addr, 6739 bool *non_constant_p) 6740 { 6741 tree r; 6742 tree orig_arg = TREE_OPERAND (t, 0); 6743 tree arg = cxx_eval_constant_expression (call, orig_arg, allow_non_constant, 6744 addr, non_constant_p); 6745 VERIFY_CONSTANT (arg); 6746 if (arg == orig_arg) 6747 return t; 6748 r = fold_build1 (TREE_CODE (t), TREE_TYPE (t), arg); 6749 VERIFY_CONSTANT (r); 6750 return r; 6751 } 6752 6753 /* Subroutine of cxx_eval_constant_expression. 6754 Like cxx_eval_unary_expression, except for binary expressions. */ 6755 6756 static tree 6757 cxx_eval_binary_expression (const constexpr_call *call, tree t, 6758 bool allow_non_constant, bool addr, 6759 bool *non_constant_p) 6760 { 6761 tree r; 6762 tree orig_lhs = TREE_OPERAND (t, 0); 6763 tree orig_rhs = TREE_OPERAND (t, 1); 6764 tree lhs, rhs; 6765 lhs = cxx_eval_constant_expression (call, orig_lhs, 6766 allow_non_constant, addr, 6767 non_constant_p); 6768 VERIFY_CONSTANT (lhs); 6769 rhs = cxx_eval_constant_expression (call, orig_rhs, 6770 allow_non_constant, addr, 6771 non_constant_p); 6772 VERIFY_CONSTANT (rhs); 6773 if (lhs == orig_lhs && rhs == orig_rhs) 6774 return t; 6775 r = fold_build2 (TREE_CODE (t), TREE_TYPE (t), lhs, rhs); 6776 VERIFY_CONSTANT (r); 6777 return r; 6778 } 6779 6780 /* Subroutine of cxx_eval_constant_expression. 6781 Attempt to evaluate condition expressions. Dead branches are not 6782 looked into. */ 6783 6784 static tree 6785 cxx_eval_conditional_expression (const constexpr_call *call, tree t, 6786 bool allow_non_constant, bool addr, 6787 bool *non_constant_p) 6788 { 6789 tree val = cxx_eval_constant_expression (call, TREE_OPERAND (t, 0), 6790 allow_non_constant, addr, 6791 non_constant_p); 6792 VERIFY_CONSTANT (val); 6793 /* Don't VERIFY_CONSTANT the other operands. */ 6794 if (integer_zerop (val)) 6795 return cxx_eval_constant_expression (call, TREE_OPERAND (t, 2), 6796 allow_non_constant, addr, 6797 non_constant_p); 6798 return cxx_eval_constant_expression (call, TREE_OPERAND (t, 1), 6799 allow_non_constant, addr, 6800 non_constant_p); 6801 } 6802 6803 /* Subroutine of cxx_eval_constant_expression. 6804 Attempt to reduce a reference to an array slot. */ 6805 6806 static tree 6807 cxx_eval_array_reference (const constexpr_call *call, tree t, 6808 bool allow_non_constant, bool addr, 6809 bool *non_constant_p) 6810 { 6811 tree oldary = TREE_OPERAND (t, 0); 6812 tree ary = cxx_eval_constant_expression (call, oldary, 6813 allow_non_constant, addr, 6814 non_constant_p); 6815 tree index, oldidx; 6816 HOST_WIDE_INT i; 6817 tree elem_type; 6818 unsigned len, elem_nchars = 1; 6819 if (*non_constant_p) 6820 return t; 6821 oldidx = TREE_OPERAND (t, 1); 6822 index = cxx_eval_constant_expression (call, oldidx, 6823 allow_non_constant, false, 6824 non_constant_p); 6825 VERIFY_CONSTANT (index); 6826 if (addr && ary == oldary && index == oldidx) 6827 return t; 6828 else if (addr) 6829 return build4 (ARRAY_REF, TREE_TYPE (t), ary, index, NULL, NULL); 6830 elem_type = TREE_TYPE (TREE_TYPE (ary)); 6831 if (TREE_CODE (ary) == CONSTRUCTOR) 6832 len = CONSTRUCTOR_NELTS (ary); 6833 else if (TREE_CODE (ary) == STRING_CST) 6834 { 6835 elem_nchars = (TYPE_PRECISION (elem_type) 6836 / TYPE_PRECISION (char_type_node)); 6837 len = (unsigned) TREE_STRING_LENGTH (ary) / elem_nchars; 6838 } 6839 else 6840 { 6841 /* We can't do anything with other tree codes, so use 6842 VERIFY_CONSTANT to complain and fail. */ 6843 VERIFY_CONSTANT (ary); 6844 gcc_unreachable (); 6845 } 6846 if (compare_tree_int (index, len) >= 0) 6847 { 6848 if (tree_int_cst_lt (index, array_type_nelts_top (TREE_TYPE (ary)))) 6849 { 6850 /* If it's within the array bounds but doesn't have an explicit 6851 initializer, it's value-initialized. */ 6852 tree val = build_value_init (elem_type, tf_warning_or_error); 6853 return cxx_eval_constant_expression (call, val, 6854 allow_non_constant, addr, 6855 non_constant_p); 6856 } 6857 6858 if (!allow_non_constant) 6859 error ("array subscript out of bound"); 6860 *non_constant_p = true; 6861 return t; 6862 } 6863 i = tree_low_cst (index, 0); 6864 if (TREE_CODE (ary) == CONSTRUCTOR) 6865 return VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ary), i)->value; 6866 else if (elem_nchars == 1) 6867 return build_int_cst (cv_unqualified (TREE_TYPE (TREE_TYPE (ary))), 6868 TREE_STRING_POINTER (ary)[i]); 6869 else 6870 { 6871 tree type = cv_unqualified (TREE_TYPE (TREE_TYPE (ary))); 6872 return native_interpret_expr (type, (const unsigned char *) 6873 TREE_STRING_POINTER (ary) 6874 + i * elem_nchars, elem_nchars); 6875 } 6876 /* Don't VERIFY_CONSTANT here. */ 6877 } 6878 6879 /* Subroutine of cxx_eval_constant_expression. 6880 Attempt to reduce a field access of a value of class type. */ 6881 6882 static tree 6883 cxx_eval_component_reference (const constexpr_call *call, tree t, 6884 bool allow_non_constant, bool addr, 6885 bool *non_constant_p) 6886 { 6887 unsigned HOST_WIDE_INT i; 6888 tree field; 6889 tree value; 6890 tree part = TREE_OPERAND (t, 1); 6891 tree orig_whole = TREE_OPERAND (t, 0); 6892 tree whole = cxx_eval_constant_expression (call, orig_whole, 6893 allow_non_constant, addr, 6894 non_constant_p); 6895 if (whole == orig_whole) 6896 return t; 6897 if (addr) 6898 return fold_build3 (COMPONENT_REF, TREE_TYPE (t), 6899 whole, part, NULL_TREE); 6900 /* Don't VERIFY_CONSTANT here; we only want to check that we got a 6901 CONSTRUCTOR. */ 6902 if (!*non_constant_p && TREE_CODE (whole) != CONSTRUCTOR) 6903 { 6904 if (!allow_non_constant) 6905 error ("%qE is not a constant expression", orig_whole); 6906 *non_constant_p = true; 6907 } 6908 if (DECL_MUTABLE_P (part)) 6909 { 6910 if (!allow_non_constant) 6911 error ("mutable %qD is not usable in a constant expression", part); 6912 *non_constant_p = true; 6913 } 6914 if (*non_constant_p) 6915 return t; 6916 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (whole), i, field, value) 6917 { 6918 if (field == part) 6919 return value; 6920 } 6921 if (TREE_CODE (TREE_TYPE (whole)) == UNION_TYPE 6922 && CONSTRUCTOR_NELTS (whole) > 0) 6923 { 6924 /* DR 1188 says we don't have to deal with this. */ 6925 if (!allow_non_constant) 6926 error ("accessing %qD member instead of initialized %qD member in " 6927 "constant expression", part, CONSTRUCTOR_ELT (whole, 0)->index); 6928 *non_constant_p = true; 6929 return t; 6930 } 6931 6932 /* If there's no explicit init for this field, it's value-initialized. */ 6933 value = build_value_init (TREE_TYPE (t), tf_warning_or_error); 6934 return cxx_eval_constant_expression (call, value, 6935 allow_non_constant, addr, 6936 non_constant_p); 6937 } 6938 6939 /* Subroutine of cxx_eval_constant_expression. 6940 Attempt to reduce a field access of a value of class type that is 6941 expressed as a BIT_FIELD_REF. */ 6942 6943 static tree 6944 cxx_eval_bit_field_ref (const constexpr_call *call, tree t, 6945 bool allow_non_constant, bool addr, 6946 bool *non_constant_p) 6947 { 6948 tree orig_whole = TREE_OPERAND (t, 0); 6949 tree retval, fldval, utype, mask; 6950 bool fld_seen = false; 6951 HOST_WIDE_INT istart, isize; 6952 tree whole = cxx_eval_constant_expression (call, orig_whole, 6953 allow_non_constant, addr, 6954 non_constant_p); 6955 tree start, field, value; 6956 unsigned HOST_WIDE_INT i; 6957 6958 if (whole == orig_whole) 6959 return t; 6960 /* Don't VERIFY_CONSTANT here; we only want to check that we got a 6961 CONSTRUCTOR. */ 6962 if (!*non_constant_p && TREE_CODE (whole) != CONSTRUCTOR) 6963 { 6964 if (!allow_non_constant) 6965 error ("%qE is not a constant expression", orig_whole); 6966 *non_constant_p = true; 6967 } 6968 if (*non_constant_p) 6969 return t; 6970 6971 start = TREE_OPERAND (t, 2); 6972 istart = tree_low_cst (start, 0); 6973 isize = tree_low_cst (TREE_OPERAND (t, 1), 0); 6974 utype = TREE_TYPE (t); 6975 if (!TYPE_UNSIGNED (utype)) 6976 utype = build_nonstandard_integer_type (TYPE_PRECISION (utype), 1); 6977 retval = build_int_cst (utype, 0); 6978 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (whole), i, field, value) 6979 { 6980 tree bitpos = bit_position (field); 6981 if (bitpos == start && DECL_SIZE (field) == TREE_OPERAND (t, 1)) 6982 return value; 6983 if (TREE_CODE (TREE_TYPE (field)) == INTEGER_TYPE 6984 && TREE_CODE (value) == INTEGER_CST 6985 && host_integerp (bitpos, 0) 6986 && host_integerp (DECL_SIZE (field), 0)) 6987 { 6988 HOST_WIDE_INT bit = tree_low_cst (bitpos, 0); 6989 HOST_WIDE_INT sz = tree_low_cst (DECL_SIZE (field), 0); 6990 HOST_WIDE_INT shift; 6991 if (bit >= istart && bit + sz <= istart + isize) 6992 { 6993 fldval = fold_convert (utype, value); 6994 mask = build_int_cst_type (utype, -1); 6995 mask = fold_build2 (LSHIFT_EXPR, utype, mask, 6996 size_int (TYPE_PRECISION (utype) - sz)); 6997 mask = fold_build2 (RSHIFT_EXPR, utype, mask, 6998 size_int (TYPE_PRECISION (utype) - sz)); 6999 fldval = fold_build2 (BIT_AND_EXPR, utype, fldval, mask); 7000 shift = bit - istart; 7001 if (BYTES_BIG_ENDIAN) 7002 shift = TYPE_PRECISION (utype) - shift - sz; 7003 fldval = fold_build2 (LSHIFT_EXPR, utype, fldval, 7004 size_int (shift)); 7005 retval = fold_build2 (BIT_IOR_EXPR, utype, retval, fldval); 7006 fld_seen = true; 7007 } 7008 } 7009 } 7010 if (fld_seen) 7011 return fold_convert (TREE_TYPE (t), retval); 7012 gcc_unreachable (); 7013 return error_mark_node; 7014 } 7015 7016 /* Subroutine of cxx_eval_constant_expression. 7017 Evaluate a short-circuited logical expression T in the context 7018 of a given constexpr CALL. BAILOUT_VALUE is the value for 7019 early return. CONTINUE_VALUE is used here purely for 7020 sanity check purposes. */ 7021 7022 static tree 7023 cxx_eval_logical_expression (const constexpr_call *call, tree t, 7024 tree bailout_value, tree continue_value, 7025 bool allow_non_constant, bool addr, 7026 bool *non_constant_p) 7027 { 7028 tree r; 7029 tree lhs = cxx_eval_constant_expression (call, TREE_OPERAND (t, 0), 7030 allow_non_constant, addr, 7031 non_constant_p); 7032 VERIFY_CONSTANT (lhs); 7033 if (tree_int_cst_equal (lhs, bailout_value)) 7034 return lhs; 7035 gcc_assert (tree_int_cst_equal (lhs, continue_value)); 7036 r = cxx_eval_constant_expression (call, TREE_OPERAND (t, 1), 7037 allow_non_constant, addr, non_constant_p); 7038 VERIFY_CONSTANT (r); 7039 return r; 7040 } 7041 7042 /* REF is a COMPONENT_REF designating a particular field. V is a vector of 7043 CONSTRUCTOR elements to initialize (part of) an object containing that 7044 field. Return a pointer to the constructor_elt corresponding to the 7045 initialization of the field. */ 7046 7047 static constructor_elt * 7048 base_field_constructor_elt (VEC(constructor_elt,gc) *v, tree ref) 7049 { 7050 tree aggr = TREE_OPERAND (ref, 0); 7051 tree field = TREE_OPERAND (ref, 1); 7052 HOST_WIDE_INT i; 7053 constructor_elt *ce; 7054 7055 gcc_assert (TREE_CODE (ref) == COMPONENT_REF); 7056 7057 if (TREE_CODE (aggr) == COMPONENT_REF) 7058 { 7059 constructor_elt *base_ce 7060 = base_field_constructor_elt (v, aggr); 7061 v = CONSTRUCTOR_ELTS (base_ce->value); 7062 } 7063 7064 for (i = 0; VEC_iterate (constructor_elt, v, i, ce); ++i) 7065 if (ce->index == field) 7066 return ce; 7067 7068 gcc_unreachable (); 7069 return NULL; 7070 } 7071 7072 /* Subroutine of cxx_eval_constant_expression. 7073 The expression tree T denotes a C-style array or a C-style 7074 aggregate. Reduce it to a constant expression. */ 7075 7076 static tree 7077 cxx_eval_bare_aggregate (const constexpr_call *call, tree t, 7078 bool allow_non_constant, bool addr, 7079 bool *non_constant_p) 7080 { 7081 VEC(constructor_elt,gc) *v = CONSTRUCTOR_ELTS (t); 7082 VEC(constructor_elt,gc) *n = VEC_alloc (constructor_elt, gc, 7083 VEC_length (constructor_elt, v)); 7084 constructor_elt *ce; 7085 HOST_WIDE_INT i; 7086 bool changed = false; 7087 gcc_assert (!BRACE_ENCLOSED_INITIALIZER_P (t)); 7088 for (i = 0; VEC_iterate (constructor_elt, v, i, ce); ++i) 7089 { 7090 tree elt = cxx_eval_constant_expression (call, ce->value, 7091 allow_non_constant, addr, 7092 non_constant_p); 7093 /* Don't VERIFY_CONSTANT here. */ 7094 if (allow_non_constant && *non_constant_p) 7095 goto fail; 7096 if (elt != ce->value) 7097 changed = true; 7098 if (TREE_CODE (ce->index) == COMPONENT_REF) 7099 { 7100 /* This is an initialization of a vfield inside a base 7101 subaggregate that we already initialized; push this 7102 initialization into the previous initialization. */ 7103 constructor_elt *inner = base_field_constructor_elt (n, ce->index); 7104 inner->value = elt; 7105 } 7106 else if (TREE_CODE (ce->index) == NOP_EXPR) 7107 { 7108 /* This is an initializer for an empty base; now that we've 7109 checked that it's constant, we can ignore it. */ 7110 gcc_assert (is_empty_class (TREE_TYPE (TREE_TYPE (ce->index)))); 7111 } 7112 else 7113 CONSTRUCTOR_APPEND_ELT (n, ce->index, elt); 7114 } 7115 if (*non_constant_p || !changed) 7116 { 7117 fail: 7118 VEC_free (constructor_elt, gc, n); 7119 return t; 7120 } 7121 t = build_constructor (TREE_TYPE (t), n); 7122 TREE_CONSTANT (t) = true; 7123 return t; 7124 } 7125 7126 /* Subroutine of cxx_eval_constant_expression. 7127 The expression tree T is a VEC_INIT_EXPR which denotes the desired 7128 initialization of a non-static data member of array type. Reduce it to a 7129 CONSTRUCTOR. 7130 7131 Note that apart from value-initialization (when VALUE_INIT is true), 7132 this is only intended to support value-initialization and the 7133 initializations done by defaulted constructors for classes with 7134 non-static data members of array type. In this case, VEC_INIT_EXPR_INIT 7135 will either be NULL_TREE for the default constructor, or a COMPONENT_REF 7136 for the copy/move constructor. */ 7137 7138 static tree 7139 cxx_eval_vec_init_1 (const constexpr_call *call, tree atype, tree init, 7140 bool value_init, bool allow_non_constant, bool addr, 7141 bool *non_constant_p) 7142 { 7143 tree elttype = TREE_TYPE (atype); 7144 int max = tree_low_cst (array_type_nelts (atype), 0); 7145 VEC(constructor_elt,gc) *n = VEC_alloc (constructor_elt, gc, max + 1); 7146 bool pre_init = false; 7147 int i; 7148 7149 /* For the default constructor, build up a call to the default 7150 constructor of the element type. We only need to handle class types 7151 here, as for a constructor to be constexpr, all members must be 7152 initialized, which for a defaulted default constructor means they must 7153 be of a class type with a constexpr default constructor. */ 7154 if (TREE_CODE (elttype) == ARRAY_TYPE) 7155 /* We only do this at the lowest level. */; 7156 else if (value_init) 7157 { 7158 init = build_value_init (elttype, tf_warning_or_error); 7159 init = cxx_eval_constant_expression 7160 (call, init, allow_non_constant, addr, non_constant_p); 7161 pre_init = true; 7162 } 7163 else if (!init) 7164 { 7165 VEC(tree,gc) *argvec = make_tree_vector (); 7166 init = build_special_member_call (NULL_TREE, complete_ctor_identifier, 7167 &argvec, elttype, LOOKUP_NORMAL, 7168 tf_warning_or_error); 7169 release_tree_vector (argvec); 7170 init = cxx_eval_constant_expression (call, init, allow_non_constant, 7171 addr, non_constant_p); 7172 pre_init = true; 7173 } 7174 7175 if (*non_constant_p && !allow_non_constant) 7176 goto fail; 7177 7178 for (i = 0; i <= max; ++i) 7179 { 7180 tree idx = build_int_cst (size_type_node, i); 7181 tree eltinit; 7182 if (TREE_CODE (elttype) == ARRAY_TYPE) 7183 { 7184 /* A multidimensional array; recurse. */ 7185 if (value_init || init == NULL_TREE) 7186 eltinit = NULL_TREE; 7187 else 7188 eltinit = cp_build_array_ref (input_location, init, idx, 7189 tf_warning_or_error); 7190 eltinit = cxx_eval_vec_init_1 (call, elttype, eltinit, value_init, 7191 allow_non_constant, addr, 7192 non_constant_p); 7193 } 7194 else if (pre_init) 7195 { 7196 /* Initializing an element using value or default initialization 7197 we just pre-built above. */ 7198 if (i == 0) 7199 eltinit = init; 7200 else 7201 eltinit = unshare_expr (init); 7202 } 7203 else 7204 { 7205 /* Copying an element. */ 7206 VEC(tree,gc) *argvec; 7207 gcc_assert (same_type_ignoring_top_level_qualifiers_p 7208 (atype, TREE_TYPE (init))); 7209 eltinit = cp_build_array_ref (input_location, init, idx, 7210 tf_warning_or_error); 7211 if (!real_lvalue_p (init)) 7212 eltinit = move (eltinit); 7213 argvec = make_tree_vector (); 7214 VEC_quick_push (tree, argvec, eltinit); 7215 eltinit = (build_special_member_call 7216 (NULL_TREE, complete_ctor_identifier, &argvec, 7217 elttype, LOOKUP_NORMAL, tf_warning_or_error)); 7218 release_tree_vector (argvec); 7219 eltinit = cxx_eval_constant_expression 7220 (call, eltinit, allow_non_constant, addr, non_constant_p); 7221 } 7222 if (*non_constant_p && !allow_non_constant) 7223 goto fail; 7224 CONSTRUCTOR_APPEND_ELT (n, idx, eltinit); 7225 } 7226 7227 if (!*non_constant_p) 7228 { 7229 init = build_constructor (atype, n); 7230 TREE_CONSTANT (init) = true; 7231 return init; 7232 } 7233 7234 fail: 7235 VEC_free (constructor_elt, gc, n); 7236 return init; 7237 } 7238 7239 static tree 7240 cxx_eval_vec_init (const constexpr_call *call, tree t, 7241 bool allow_non_constant, bool addr, 7242 bool *non_constant_p) 7243 { 7244 tree atype = TREE_TYPE (t); 7245 tree init = VEC_INIT_EXPR_INIT (t); 7246 tree r = cxx_eval_vec_init_1 (call, atype, init, 7247 VEC_INIT_EXPR_VALUE_INIT (t), 7248 allow_non_constant, addr, non_constant_p); 7249 if (*non_constant_p) 7250 return t; 7251 else 7252 return r; 7253 } 7254 7255 /* A less strict version of fold_indirect_ref_1, which requires cv-quals to 7256 match. We want to be less strict for simple *& folding; if we have a 7257 non-const temporary that we access through a const pointer, that should 7258 work. We handle this here rather than change fold_indirect_ref_1 7259 because we're dealing with things like ADDR_EXPR of INTEGER_CST which 7260 don't really make sense outside of constant expression evaluation. Also 7261 we want to allow folding to COMPONENT_REF, which could cause trouble 7262 with TBAA in fold_indirect_ref_1. 7263 7264 Try to keep this function synced with fold_indirect_ref_1. */ 7265 7266 static tree 7267 cxx_fold_indirect_ref (location_t loc, tree type, tree op0, bool *empty_base) 7268 { 7269 tree sub, subtype; 7270 7271 sub = op0; 7272 STRIP_NOPS (sub); 7273 subtype = TREE_TYPE (sub); 7274 if (!POINTER_TYPE_P (subtype)) 7275 return NULL_TREE; 7276 7277 if (TREE_CODE (sub) == ADDR_EXPR) 7278 { 7279 tree op = TREE_OPERAND (sub, 0); 7280 tree optype = TREE_TYPE (op); 7281 7282 /* *&CONST_DECL -> to the value of the const decl. */ 7283 if (TREE_CODE (op) == CONST_DECL) 7284 return DECL_INITIAL (op); 7285 /* *&p => p; make sure to handle *&"str"[cst] here. */ 7286 if (same_type_ignoring_top_level_qualifiers_p (optype, type)) 7287 { 7288 tree fop = fold_read_from_constant_string (op); 7289 if (fop) 7290 return fop; 7291 else 7292 return op; 7293 } 7294 /* *(foo *)&fooarray => fooarray[0] */ 7295 else if (TREE_CODE (optype) == ARRAY_TYPE 7296 && (same_type_ignoring_top_level_qualifiers_p 7297 (type, TREE_TYPE (optype)))) 7298 { 7299 tree type_domain = TYPE_DOMAIN (optype); 7300 tree min_val = size_zero_node; 7301 if (type_domain && TYPE_MIN_VALUE (type_domain)) 7302 min_val = TYPE_MIN_VALUE (type_domain); 7303 return build4_loc (loc, ARRAY_REF, type, op, min_val, 7304 NULL_TREE, NULL_TREE); 7305 } 7306 /* *(foo *)&complexfoo => __real__ complexfoo */ 7307 else if (TREE_CODE (optype) == COMPLEX_TYPE 7308 && (same_type_ignoring_top_level_qualifiers_p 7309 (type, TREE_TYPE (optype)))) 7310 return fold_build1_loc (loc, REALPART_EXPR, type, op); 7311 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */ 7312 else if (TREE_CODE (optype) == VECTOR_TYPE 7313 && (same_type_ignoring_top_level_qualifiers_p 7314 (type, TREE_TYPE (optype)))) 7315 { 7316 tree part_width = TYPE_SIZE (type); 7317 tree index = bitsize_int (0); 7318 return fold_build3_loc (loc, BIT_FIELD_REF, type, op, part_width, index); 7319 } 7320 /* Also handle conversion to an empty base class, which 7321 is represented with a NOP_EXPR. */ 7322 else if (is_empty_class (type) 7323 && CLASS_TYPE_P (optype) 7324 && DERIVED_FROM_P (type, optype)) 7325 { 7326 *empty_base = true; 7327 return op; 7328 } 7329 /* *(foo *)&struct_with_foo_field => COMPONENT_REF */ 7330 else if (RECORD_OR_UNION_TYPE_P (optype)) 7331 { 7332 tree field = TYPE_FIELDS (optype); 7333 for (; field; field = DECL_CHAIN (field)) 7334 if (TREE_CODE (field) == FIELD_DECL 7335 && integer_zerop (byte_position (field)) 7336 && (same_type_ignoring_top_level_qualifiers_p 7337 (TREE_TYPE (field), type))) 7338 { 7339 return fold_build3 (COMPONENT_REF, type, op, field, NULL_TREE); 7340 break; 7341 } 7342 } 7343 } 7344 else if (TREE_CODE (sub) == POINTER_PLUS_EXPR 7345 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST) 7346 { 7347 tree op00 = TREE_OPERAND (sub, 0); 7348 tree op01 = TREE_OPERAND (sub, 1); 7349 7350 STRIP_NOPS (op00); 7351 if (TREE_CODE (op00) == ADDR_EXPR) 7352 { 7353 tree op00type; 7354 op00 = TREE_OPERAND (op00, 0); 7355 op00type = TREE_TYPE (op00); 7356 7357 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */ 7358 if (TREE_CODE (op00type) == VECTOR_TYPE 7359 && (same_type_ignoring_top_level_qualifiers_p 7360 (type, TREE_TYPE (op00type)))) 7361 { 7362 HOST_WIDE_INT offset = tree_low_cst (op01, 0); 7363 tree part_width = TYPE_SIZE (type); 7364 unsigned HOST_WIDE_INT part_widthi = tree_low_cst (part_width, 0)/BITS_PER_UNIT; 7365 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT; 7366 tree index = bitsize_int (indexi); 7367 7368 if (offset/part_widthi <= TYPE_VECTOR_SUBPARTS (op00type)) 7369 return fold_build3_loc (loc, 7370 BIT_FIELD_REF, type, op00, 7371 part_width, index); 7372 7373 } 7374 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */ 7375 else if (TREE_CODE (op00type) == COMPLEX_TYPE 7376 && (same_type_ignoring_top_level_qualifiers_p 7377 (type, TREE_TYPE (op00type)))) 7378 { 7379 tree size = TYPE_SIZE_UNIT (type); 7380 if (tree_int_cst_equal (size, op01)) 7381 return fold_build1_loc (loc, IMAGPART_EXPR, type, op00); 7382 } 7383 /* ((foo *)&fooarray)[1] => fooarray[1] */ 7384 else if (TREE_CODE (op00type) == ARRAY_TYPE 7385 && (same_type_ignoring_top_level_qualifiers_p 7386 (type, TREE_TYPE (op00type)))) 7387 { 7388 tree type_domain = TYPE_DOMAIN (op00type); 7389 tree min_val = size_zero_node; 7390 if (type_domain && TYPE_MIN_VALUE (type_domain)) 7391 min_val = TYPE_MIN_VALUE (type_domain); 7392 op01 = size_binop_loc (loc, EXACT_DIV_EXPR, op01, 7393 TYPE_SIZE_UNIT (type)); 7394 op01 = size_binop_loc (loc, PLUS_EXPR, op01, min_val); 7395 return build4_loc (loc, ARRAY_REF, type, op00, op01, 7396 NULL_TREE, NULL_TREE); 7397 } 7398 /* ((foo *)&struct_with_foo_field)[1] => COMPONENT_REF */ 7399 else if (RECORD_OR_UNION_TYPE_P (op00type)) 7400 { 7401 tree field = TYPE_FIELDS (op00type); 7402 for (; field; field = DECL_CHAIN (field)) 7403 if (TREE_CODE (field) == FIELD_DECL 7404 && tree_int_cst_equal (byte_position (field), op01) 7405 && (same_type_ignoring_top_level_qualifiers_p 7406 (TREE_TYPE (field), type))) 7407 { 7408 return fold_build3 (COMPONENT_REF, type, op00, 7409 field, NULL_TREE); 7410 break; 7411 } 7412 } 7413 } 7414 } 7415 /* *(foo *)fooarrptreturn> (*fooarrptr)[0] */ 7416 else if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE 7417 && (same_type_ignoring_top_level_qualifiers_p 7418 (type, TREE_TYPE (TREE_TYPE (subtype))))) 7419 { 7420 tree type_domain; 7421 tree min_val = size_zero_node; 7422 sub = cxx_fold_indirect_ref (loc, TREE_TYPE (subtype), sub, NULL); 7423 if (!sub) 7424 sub = build1_loc (loc, INDIRECT_REF, TREE_TYPE (subtype), sub); 7425 type_domain = TYPE_DOMAIN (TREE_TYPE (sub)); 7426 if (type_domain && TYPE_MIN_VALUE (type_domain)) 7427 min_val = TYPE_MIN_VALUE (type_domain); 7428 return build4_loc (loc, ARRAY_REF, type, sub, min_val, NULL_TREE, 7429 NULL_TREE); 7430 } 7431 7432 return NULL_TREE; 7433 } 7434 7435 static tree 7436 cxx_eval_indirect_ref (const constexpr_call *call, tree t, 7437 bool allow_non_constant, bool addr, 7438 bool *non_constant_p) 7439 { 7440 tree orig_op0 = TREE_OPERAND (t, 0); 7441 tree op0 = cxx_eval_constant_expression (call, orig_op0, allow_non_constant, 7442 /*addr*/false, non_constant_p); 7443 bool empty_base = false; 7444 tree r; 7445 7446 /* Don't VERIFY_CONSTANT here. */ 7447 if (*non_constant_p) 7448 return t; 7449 7450 r = cxx_fold_indirect_ref (EXPR_LOCATION (t), TREE_TYPE (t), op0, 7451 &empty_base); 7452 7453 if (r) 7454 r = cxx_eval_constant_expression (call, r, allow_non_constant, 7455 addr, non_constant_p); 7456 else 7457 { 7458 tree sub = op0; 7459 STRIP_NOPS (sub); 7460 if (TREE_CODE (sub) == POINTER_PLUS_EXPR) 7461 { 7462 sub = TREE_OPERAND (sub, 0); 7463 STRIP_NOPS (sub); 7464 } 7465 if (TREE_CODE (sub) == ADDR_EXPR) 7466 { 7467 /* We couldn't fold to a constant value. Make sure it's not 7468 something we should have been able to fold. */ 7469 gcc_assert (!same_type_ignoring_top_level_qualifiers_p 7470 (TREE_TYPE (TREE_TYPE (sub)), TREE_TYPE (t))); 7471 /* DR 1188 says we don't have to deal with this. */ 7472 if (!allow_non_constant) 7473 error ("accessing value of %qE through a %qT glvalue in a " 7474 "constant expression", build_fold_indirect_ref (sub), 7475 TREE_TYPE (t)); 7476 *non_constant_p = true; 7477 return t; 7478 } 7479 } 7480 7481 /* If we're pulling out the value of an empty base, make sure 7482 that the whole object is constant and then return an empty 7483 CONSTRUCTOR. */ 7484 if (empty_base) 7485 { 7486 VERIFY_CONSTANT (r); 7487 r = build_constructor (TREE_TYPE (t), NULL); 7488 TREE_CONSTANT (r) = true; 7489 } 7490 7491 if (r == NULL_TREE) 7492 { 7493 if (!addr) 7494 VERIFY_CONSTANT (t); 7495 return t; 7496 } 7497 return r; 7498 } 7499 7500 /* Complain about R, a VAR_DECL, not being usable in a constant expression. 7501 Shared between potential_constant_expression and 7502 cxx_eval_constant_expression. */ 7503 7504 static void 7505 non_const_var_error (tree r) 7506 { 7507 tree type = TREE_TYPE (r); 7508 error ("the value of %qD is not usable in a constant " 7509 "expression", r); 7510 /* Avoid error cascade. */ 7511 if (DECL_INITIAL (r) == error_mark_node) 7512 return; 7513 if (DECL_DECLARED_CONSTEXPR_P (r)) 7514 inform (DECL_SOURCE_LOCATION (r), 7515 "%qD used in its own initializer", r); 7516 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (type)) 7517 { 7518 if (!CP_TYPE_CONST_P (type)) 7519 inform (DECL_SOURCE_LOCATION (r), 7520 "%q#D is not const", r); 7521 else if (CP_TYPE_VOLATILE_P (type)) 7522 inform (DECL_SOURCE_LOCATION (r), 7523 "%q#D is volatile", r); 7524 else if (!DECL_INITIAL (r) 7525 || !TREE_CONSTANT (DECL_INITIAL (r))) 7526 inform (DECL_SOURCE_LOCATION (r), 7527 "%qD was not initialized with a constant " 7528 "expression", r); 7529 else 7530 gcc_unreachable (); 7531 } 7532 else 7533 { 7534 if (cxx_dialect >= cxx0x && !DECL_DECLARED_CONSTEXPR_P (r)) 7535 inform (DECL_SOURCE_LOCATION (r), 7536 "%qD was not declared %<constexpr%>", r); 7537 else 7538 inform (DECL_SOURCE_LOCATION (r), 7539 "%qD does not have integral or enumeration type", 7540 r); 7541 } 7542 } 7543 7544 /* Attempt to reduce the expression T to a constant value. 7545 On failure, issue diagnostic and return error_mark_node. */ 7546 /* FIXME unify with c_fully_fold */ 7547 7548 static tree 7549 cxx_eval_constant_expression (const constexpr_call *call, tree t, 7550 bool allow_non_constant, bool addr, 7551 bool *non_constant_p) 7552 { 7553 tree r = t; 7554 7555 if (t == error_mark_node) 7556 { 7557 *non_constant_p = true; 7558 return t; 7559 } 7560 if (CONSTANT_CLASS_P (t)) 7561 { 7562 if (TREE_CODE (t) == PTRMEM_CST) 7563 t = cplus_expand_constant (t); 7564 return t; 7565 } 7566 if (TREE_CODE (t) != NOP_EXPR 7567 && reduced_constant_expression_p (t)) 7568 return fold (t); 7569 7570 switch (TREE_CODE (t)) 7571 { 7572 case VAR_DECL: 7573 if (addr) 7574 return t; 7575 /* else fall through. */ 7576 case CONST_DECL: 7577 r = integral_constant_value (t); 7578 if (TREE_CODE (r) == TARGET_EXPR 7579 && TREE_CODE (TARGET_EXPR_INITIAL (r)) == CONSTRUCTOR) 7580 r = TARGET_EXPR_INITIAL (r); 7581 if (DECL_P (r)) 7582 { 7583 if (!allow_non_constant) 7584 non_const_var_error (r); 7585 *non_constant_p = true; 7586 } 7587 break; 7588 7589 case FUNCTION_DECL: 7590 case TEMPLATE_DECL: 7591 case LABEL_DECL: 7592 return t; 7593 7594 case PARM_DECL: 7595 if (call && DECL_CONTEXT (t) == call->fundef->decl) 7596 { 7597 if (DECL_ARTIFICIAL (t) && DECL_CONSTRUCTOR_P (DECL_CONTEXT (t))) 7598 { 7599 if (!allow_non_constant) 7600 sorry ("use of the value of the object being constructed " 7601 "in a constant expression"); 7602 *non_constant_p = true; 7603 } 7604 else 7605 r = lookup_parameter_binding (call, t); 7606 } 7607 else if (addr) 7608 /* Defer in case this is only used for its type. */; 7609 else 7610 { 7611 if (!allow_non_constant) 7612 error ("%qE is not a constant expression", t); 7613 *non_constant_p = true; 7614 } 7615 break; 7616 7617 case CALL_EXPR: 7618 case AGGR_INIT_EXPR: 7619 r = cxx_eval_call_expression (call, t, allow_non_constant, addr, 7620 non_constant_p); 7621 break; 7622 7623 case TARGET_EXPR: 7624 if (!literal_type_p (TREE_TYPE (t))) 7625 { 7626 if (!allow_non_constant) 7627 { 7628 error ("temporary of non-literal type %qT in a " 7629 "constant expression", TREE_TYPE (t)); 7630 explain_non_literal_class (TREE_TYPE (t)); 7631 } 7632 *non_constant_p = true; 7633 break; 7634 } 7635 /* else fall through. */ 7636 case INIT_EXPR: 7637 /* Pass false for 'addr' because these codes indicate 7638 initialization of a temporary. */ 7639 r = cxx_eval_constant_expression (call, TREE_OPERAND (t, 1), 7640 allow_non_constant, false, 7641 non_constant_p); 7642 if (!*non_constant_p) 7643 /* Adjust the type of the result to the type of the temporary. */ 7644 r = adjust_temp_type (TREE_TYPE (t), r); 7645 break; 7646 7647 case SCOPE_REF: 7648 r = cxx_eval_constant_expression (call, TREE_OPERAND (t, 1), 7649 allow_non_constant, addr, 7650 non_constant_p); 7651 break; 7652 7653 case RETURN_EXPR: 7654 case NON_LVALUE_EXPR: 7655 case TRY_CATCH_EXPR: 7656 case CLEANUP_POINT_EXPR: 7657 case MUST_NOT_THROW_EXPR: 7658 case SAVE_EXPR: 7659 r = cxx_eval_constant_expression (call, TREE_OPERAND (t, 0), 7660 allow_non_constant, addr, 7661 non_constant_p); 7662 break; 7663 7664 /* These differ from cxx_eval_unary_expression in that this doesn't 7665 check for a constant operand or result; an address can be 7666 constant without its operand being, and vice versa. */ 7667 case INDIRECT_REF: 7668 r = cxx_eval_indirect_ref (call, t, allow_non_constant, addr, 7669 non_constant_p); 7670 break; 7671 7672 case ADDR_EXPR: 7673 { 7674 tree oldop = TREE_OPERAND (t, 0); 7675 tree op = cxx_eval_constant_expression (call, oldop, 7676 allow_non_constant, 7677 /*addr*/true, 7678 non_constant_p); 7679 /* Don't VERIFY_CONSTANT here. */ 7680 if (*non_constant_p) 7681 return t; 7682 /* This function does more aggressive folding than fold itself. */ 7683 r = build_fold_addr_expr_with_type (op, TREE_TYPE (t)); 7684 if (TREE_CODE (r) == ADDR_EXPR && TREE_OPERAND (r, 0) == oldop) 7685 return t; 7686 break; 7687 } 7688 7689 case REALPART_EXPR: 7690 case IMAGPART_EXPR: 7691 case CONJ_EXPR: 7692 case FIX_TRUNC_EXPR: 7693 case FLOAT_EXPR: 7694 case NEGATE_EXPR: 7695 case ABS_EXPR: 7696 case BIT_NOT_EXPR: 7697 case TRUTH_NOT_EXPR: 7698 case FIXED_CONVERT_EXPR: 7699 r = cxx_eval_unary_expression (call, t, allow_non_constant, addr, 7700 non_constant_p); 7701 break; 7702 7703 case COMPOUND_EXPR: 7704 { 7705 /* check_return_expr sometimes wraps a TARGET_EXPR in a 7706 COMPOUND_EXPR; don't get confused. Also handle EMPTY_CLASS_EXPR 7707 introduced by build_call_a. */ 7708 tree op0 = TREE_OPERAND (t, 0); 7709 tree op1 = TREE_OPERAND (t, 1); 7710 STRIP_NOPS (op1); 7711 if ((TREE_CODE (op0) == TARGET_EXPR && op1 == TARGET_EXPR_SLOT (op0)) 7712 || TREE_CODE (op1) == EMPTY_CLASS_EXPR) 7713 r = cxx_eval_constant_expression (call, op0, allow_non_constant, 7714 addr, non_constant_p); 7715 else 7716 { 7717 /* Check that the LHS is constant and then discard it. */ 7718 cxx_eval_constant_expression (call, op0, allow_non_constant, 7719 false, non_constant_p); 7720 op1 = TREE_OPERAND (t, 1); 7721 r = cxx_eval_constant_expression (call, op1, allow_non_constant, 7722 addr, non_constant_p); 7723 } 7724 } 7725 break; 7726 7727 case POINTER_PLUS_EXPR: 7728 case PLUS_EXPR: 7729 case MINUS_EXPR: 7730 case MULT_EXPR: 7731 case TRUNC_DIV_EXPR: 7732 case CEIL_DIV_EXPR: 7733 case FLOOR_DIV_EXPR: 7734 case ROUND_DIV_EXPR: 7735 case TRUNC_MOD_EXPR: 7736 case CEIL_MOD_EXPR: 7737 case ROUND_MOD_EXPR: 7738 case RDIV_EXPR: 7739 case EXACT_DIV_EXPR: 7740 case MIN_EXPR: 7741 case MAX_EXPR: 7742 case LSHIFT_EXPR: 7743 case RSHIFT_EXPR: 7744 case LROTATE_EXPR: 7745 case RROTATE_EXPR: 7746 case BIT_IOR_EXPR: 7747 case BIT_XOR_EXPR: 7748 case BIT_AND_EXPR: 7749 case TRUTH_XOR_EXPR: 7750 case LT_EXPR: 7751 case LE_EXPR: 7752 case GT_EXPR: 7753 case GE_EXPR: 7754 case EQ_EXPR: 7755 case NE_EXPR: 7756 case UNORDERED_EXPR: 7757 case ORDERED_EXPR: 7758 case UNLT_EXPR: 7759 case UNLE_EXPR: 7760 case UNGT_EXPR: 7761 case UNGE_EXPR: 7762 case UNEQ_EXPR: 7763 case RANGE_EXPR: 7764 case COMPLEX_EXPR: 7765 r = cxx_eval_binary_expression (call, t, allow_non_constant, addr, 7766 non_constant_p); 7767 break; 7768 7769 /* fold can introduce non-IF versions of these; still treat them as 7770 short-circuiting. */ 7771 case TRUTH_AND_EXPR: 7772 case TRUTH_ANDIF_EXPR: 7773 r = cxx_eval_logical_expression (call, t, boolean_false_node, 7774 boolean_true_node, 7775 allow_non_constant, addr, 7776 non_constant_p); 7777 break; 7778 7779 case TRUTH_OR_EXPR: 7780 case TRUTH_ORIF_EXPR: 7781 r = cxx_eval_logical_expression (call, t, boolean_true_node, 7782 boolean_false_node, 7783 allow_non_constant, addr, 7784 non_constant_p); 7785 break; 7786 7787 case ARRAY_REF: 7788 r = cxx_eval_array_reference (call, t, allow_non_constant, addr, 7789 non_constant_p); 7790 break; 7791 7792 case COMPONENT_REF: 7793 r = cxx_eval_component_reference (call, t, allow_non_constant, addr, 7794 non_constant_p); 7795 break; 7796 7797 case BIT_FIELD_REF: 7798 r = cxx_eval_bit_field_ref (call, t, allow_non_constant, addr, 7799 non_constant_p); 7800 break; 7801 7802 case COND_EXPR: 7803 case VEC_COND_EXPR: 7804 r = cxx_eval_conditional_expression (call, t, allow_non_constant, addr, 7805 non_constant_p); 7806 break; 7807 7808 case CONSTRUCTOR: 7809 r = cxx_eval_bare_aggregate (call, t, allow_non_constant, addr, 7810 non_constant_p); 7811 break; 7812 7813 case VEC_INIT_EXPR: 7814 /* We can get this in a defaulted constructor for a class with a 7815 non-static data member of array type. Either the initializer will 7816 be NULL, meaning default-initialization, or it will be an lvalue 7817 or xvalue of the same type, meaning direct-initialization from the 7818 corresponding member. */ 7819 r = cxx_eval_vec_init (call, t, allow_non_constant, addr, 7820 non_constant_p); 7821 break; 7822 7823 case CONVERT_EXPR: 7824 case VIEW_CONVERT_EXPR: 7825 case NOP_EXPR: 7826 { 7827 tree oldop = TREE_OPERAND (t, 0); 7828 tree op = oldop; 7829 tree to = TREE_TYPE (t); 7830 op = cxx_eval_constant_expression (call, TREE_OPERAND (t, 0), 7831 allow_non_constant, addr, 7832 non_constant_p); 7833 if (*non_constant_p) 7834 return t; 7835 if (op == oldop) 7836 /* We didn't fold at the top so we could check for ptr-int 7837 conversion. */ 7838 return fold (t); 7839 r = fold_build1 (TREE_CODE (t), to, op); 7840 /* Conversion of an out-of-range value has implementation-defined 7841 behavior; the language considers it different from arithmetic 7842 overflow, which is undefined. */ 7843 if (TREE_OVERFLOW_P (r) && !TREE_OVERFLOW_P (op)) 7844 TREE_OVERFLOW (r) = false; 7845 } 7846 break; 7847 7848 case EMPTY_CLASS_EXPR: 7849 /* This is good enough for a function argument that might not get 7850 used, and they can't do anything with it, so just return it. */ 7851 return t; 7852 7853 case LAMBDA_EXPR: 7854 case PREINCREMENT_EXPR: 7855 case POSTINCREMENT_EXPR: 7856 case PREDECREMENT_EXPR: 7857 case POSTDECREMENT_EXPR: 7858 case NEW_EXPR: 7859 case VEC_NEW_EXPR: 7860 case DELETE_EXPR: 7861 case VEC_DELETE_EXPR: 7862 case THROW_EXPR: 7863 case MODIFY_EXPR: 7864 case MODOP_EXPR: 7865 /* GCC internal stuff. */ 7866 case VA_ARG_EXPR: 7867 case OBJ_TYPE_REF: 7868 case WITH_CLEANUP_EXPR: 7869 case STATEMENT_LIST: 7870 case BIND_EXPR: 7871 case NON_DEPENDENT_EXPR: 7872 case BASELINK: 7873 case EXPR_STMT: 7874 case OFFSET_REF: 7875 if (!allow_non_constant) 7876 error_at (EXPR_LOC_OR_HERE (t), 7877 "expression %qE is not a constant-expression", t); 7878 *non_constant_p = true; 7879 break; 7880 7881 default: 7882 internal_error ("unexpected expression %qE of kind %s", t, 7883 tree_code_name[TREE_CODE (t)]); 7884 *non_constant_p = true; 7885 break; 7886 } 7887 7888 if (r == error_mark_node) 7889 *non_constant_p = true; 7890 7891 if (*non_constant_p) 7892 return t; 7893 else 7894 return r; 7895 } 7896 7897 static tree 7898 cxx_eval_outermost_constant_expr (tree t, bool allow_non_constant) 7899 { 7900 bool non_constant_p = false; 7901 tree r = cxx_eval_constant_expression (NULL, t, allow_non_constant, 7902 false, &non_constant_p); 7903 7904 verify_constant (r, allow_non_constant, &non_constant_p); 7905 7906 if (TREE_CODE (t) != CONSTRUCTOR 7907 && cp_has_mutable_p (TREE_TYPE (t))) 7908 { 7909 /* We allow a mutable type if the original expression was a 7910 CONSTRUCTOR so that we can do aggregate initialization of 7911 constexpr variables. */ 7912 if (!allow_non_constant) 7913 error ("%qT cannot be the type of a complete constant expression " 7914 "because it has mutable sub-objects", TREE_TYPE (t)); 7915 non_constant_p = true; 7916 } 7917 7918 /* Technically we should check this for all subexpressions, but that 7919 runs into problems with our internal representation of pointer 7920 subtraction and the 5.19 rules are still in flux. */ 7921 if (CONVERT_EXPR_CODE_P (TREE_CODE (r)) 7922 && ARITHMETIC_TYPE_P (TREE_TYPE (r)) 7923 && TREE_CODE (TREE_OPERAND (r, 0)) == ADDR_EXPR) 7924 { 7925 if (!allow_non_constant) 7926 error ("conversion from pointer type %qT " 7927 "to arithmetic type %qT in a constant-expression", 7928 TREE_TYPE (TREE_OPERAND (r, 0)), TREE_TYPE (r)); 7929 non_constant_p = true; 7930 } 7931 7932 if (non_constant_p && !allow_non_constant) 7933 return error_mark_node; 7934 else if (non_constant_p && TREE_CONSTANT (t)) 7935 { 7936 /* This isn't actually constant, so unset TREE_CONSTANT. */ 7937 if (EXPR_P (t) || TREE_CODE (t) == CONSTRUCTOR) 7938 r = copy_node (t); 7939 else 7940 r = build_nop (TREE_TYPE (t), t); 7941 TREE_CONSTANT (r) = false; 7942 return r; 7943 } 7944 else if (non_constant_p || r == t) 7945 return t; 7946 else if (TREE_CODE (r) == CONSTRUCTOR && CLASS_TYPE_P (TREE_TYPE (r))) 7947 { 7948 if (TREE_CODE (t) == TARGET_EXPR 7949 && TARGET_EXPR_INITIAL (t) == r) 7950 return t; 7951 else 7952 { 7953 r = get_target_expr (r); 7954 TREE_CONSTANT (r) = true; 7955 return r; 7956 } 7957 } 7958 else 7959 return r; 7960 } 7961 7962 /* Returns true if T is a valid subexpression of a constant expression, 7963 even if it isn't itself a constant expression. */ 7964 7965 bool 7966 is_sub_constant_expr (tree t) 7967 { 7968 bool non_constant_p = false; 7969 cxx_eval_constant_expression (NULL, t, true, false, &non_constant_p); 7970 return !non_constant_p; 7971 } 7972 7973 /* If T represents a constant expression returns its reduced value. 7974 Otherwise return error_mark_node. If T is dependent, then 7975 return NULL. */ 7976 7977 tree 7978 cxx_constant_value (tree t) 7979 { 7980 return cxx_eval_outermost_constant_expr (t, false); 7981 } 7982 7983 /* If T is a constant expression, returns its reduced value. 7984 Otherwise, if T does not have TREE_CONSTANT set, returns T. 7985 Otherwise, returns a version of T without TREE_CONSTANT. */ 7986 7987 tree 7988 maybe_constant_value (tree t) 7989 { 7990 tree r; 7991 7992 if (type_dependent_expression_p (t) 7993 || type_unknown_p (t) 7994 || BRACE_ENCLOSED_INITIALIZER_P (t) 7995 || !potential_constant_expression (t) 7996 || value_dependent_expression_p (t)) 7997 { 7998 if (TREE_OVERFLOW_P (t)) 7999 { 8000 t = build_nop (TREE_TYPE (t), t); 8001 TREE_CONSTANT (t) = false; 8002 } 8003 return t; 8004 } 8005 8006 r = cxx_eval_outermost_constant_expr (t, true); 8007 #ifdef ENABLE_CHECKING 8008 /* cp_tree_equal looks through NOPs, so allow them. */ 8009 gcc_assert (r == t 8010 || CONVERT_EXPR_P (t) 8011 || (TREE_CONSTANT (t) && !TREE_CONSTANT (r)) 8012 || !cp_tree_equal (r, t)); 8013 #endif 8014 return r; 8015 } 8016 8017 /* Like maybe_constant_value, but returns a CONSTRUCTOR directly, rather 8018 than wrapped in a TARGET_EXPR. */ 8019 8020 tree 8021 maybe_constant_init (tree t) 8022 { 8023 t = maybe_constant_value (t); 8024 if (TREE_CODE (t) == TARGET_EXPR) 8025 { 8026 tree init = TARGET_EXPR_INITIAL (t); 8027 if (TREE_CODE (init) == CONSTRUCTOR 8028 && TREE_CONSTANT (init)) 8029 t = init; 8030 } 8031 return t; 8032 } 8033 8034 #if 0 8035 /* FIXME see ADDR_EXPR section in potential_constant_expression_1. */ 8036 /* Return true if the object referred to by REF has automatic or thread 8037 local storage. */ 8038 8039 enum { ck_ok, ck_bad, ck_unknown }; 8040 static int 8041 check_automatic_or_tls (tree ref) 8042 { 8043 enum machine_mode mode; 8044 HOST_WIDE_INT bitsize, bitpos; 8045 tree offset; 8046 int volatilep = 0, unsignedp = 0; 8047 tree decl = get_inner_reference (ref, &bitsize, &bitpos, &offset, 8048 &mode, &unsignedp, &volatilep, false); 8049 duration_kind dk; 8050 8051 /* If there isn't a decl in the middle, we don't know the linkage here, 8052 and this isn't a constant expression anyway. */ 8053 if (!DECL_P (decl)) 8054 return ck_unknown; 8055 dk = decl_storage_duration (decl); 8056 return (dk == dk_auto || dk == dk_thread) ? ck_bad : ck_ok; 8057 } 8058 #endif 8059 8060 /* Return true if T denotes a potentially constant expression. Issue 8061 diagnostic as appropriate under control of FLAGS. If WANT_RVAL is true, 8062 an lvalue-rvalue conversion is implied. 8063 8064 C++0x [expr.const] used to say 8065 8066 6 An expression is a potential constant expression if it is 8067 a constant expression where all occurences of function 8068 parameters are replaced by arbitrary constant expressions 8069 of the appropriate type. 8070 8071 2 A conditional expression is a constant expression unless it 8072 involves one of the following as a potentially evaluated 8073 subexpression (3.2), but subexpressions of logical AND (5.14), 8074 logical OR (5.15), and conditional (5.16) operations that are 8075 not evaluated are not considered. */ 8076 8077 static bool 8078 potential_constant_expression_1 (tree t, bool want_rval, tsubst_flags_t flags) 8079 { 8080 enum { any = false, rval = true }; 8081 int i; 8082 tree tmp; 8083 8084 /* C++98 has different rules for the form of a constant expression that 8085 are enforced in the parser, so we can assume that anything that gets 8086 this far is suitable. */ 8087 if (cxx_dialect < cxx0x) 8088 return true; 8089 8090 if (t == error_mark_node) 8091 return false; 8092 if (t == NULL_TREE) 8093 return true; 8094 if (TREE_THIS_VOLATILE (t)) 8095 { 8096 if (flags & tf_error) 8097 error ("expression %qE has side-effects", t); 8098 return false; 8099 } 8100 if (CONSTANT_CLASS_P (t)) 8101 { 8102 if (TREE_OVERFLOW (t)) 8103 { 8104 if (flags & tf_error) 8105 { 8106 permerror (EXPR_LOC_OR_HERE (t), 8107 "overflow in constant expression"); 8108 if (flag_permissive) 8109 return true; 8110 } 8111 return false; 8112 } 8113 return true; 8114 } 8115 8116 switch (TREE_CODE (t)) 8117 { 8118 case FUNCTION_DECL: 8119 case BASELINK: 8120 case TEMPLATE_DECL: 8121 case OVERLOAD: 8122 case TEMPLATE_ID_EXPR: 8123 case LABEL_DECL: 8124 case CONST_DECL: 8125 case SIZEOF_EXPR: 8126 case ALIGNOF_EXPR: 8127 case OFFSETOF_EXPR: 8128 case NOEXCEPT_EXPR: 8129 case TEMPLATE_PARM_INDEX: 8130 case TRAIT_EXPR: 8131 case IDENTIFIER_NODE: 8132 case USERDEF_LITERAL: 8133 /* We can see a FIELD_DECL in a pointer-to-member expression. */ 8134 case FIELD_DECL: 8135 case PARM_DECL: 8136 case USING_DECL: 8137 return true; 8138 8139 case AGGR_INIT_EXPR: 8140 case CALL_EXPR: 8141 /* -- an invocation of a function other than a constexpr function 8142 or a constexpr constructor. */ 8143 { 8144 tree fun = get_function_named_in_call (t); 8145 const int nargs = call_expr_nargs (t); 8146 i = 0; 8147 8148 if (is_overloaded_fn (fun)) 8149 { 8150 if (TREE_CODE (fun) == FUNCTION_DECL) 8151 { 8152 if (builtin_valid_in_constant_expr_p (fun)) 8153 return true; 8154 if (!DECL_DECLARED_CONSTEXPR_P (fun) 8155 /* Allow any built-in function; if the expansion 8156 isn't constant, we'll deal with that then. */ 8157 && !is_builtin_fn (fun)) 8158 { 8159 if (flags & tf_error) 8160 { 8161 error_at (EXPR_LOC_OR_HERE (t), 8162 "call to non-constexpr function %qD", fun); 8163 explain_invalid_constexpr_fn (fun); 8164 } 8165 return false; 8166 } 8167 /* A call to a non-static member function takes the address 8168 of the object as the first argument. But in a constant 8169 expression the address will be folded away, so look 8170 through it now. */ 8171 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fun) 8172 && !DECL_CONSTRUCTOR_P (fun)) 8173 { 8174 tree x = get_nth_callarg (t, 0); 8175 if (is_this_parameter (x)) 8176 { 8177 if (DECL_CONSTRUCTOR_P (DECL_CONTEXT (x))) 8178 { 8179 if (flags & tf_error) 8180 sorry ("calling a member function of the " 8181 "object being constructed in a constant " 8182 "expression"); 8183 return false; 8184 } 8185 /* Otherwise OK. */; 8186 } 8187 else if (!potential_constant_expression_1 (x, rval, flags)) 8188 return false; 8189 i = 1; 8190 } 8191 } 8192 else 8193 fun = get_first_fn (fun); 8194 /* Skip initial arguments to base constructors. */ 8195 if (DECL_BASE_CONSTRUCTOR_P (fun)) 8196 i = num_artificial_parms_for (fun); 8197 fun = DECL_ORIGIN (fun); 8198 } 8199 else 8200 { 8201 if (potential_constant_expression_1 (fun, rval, flags)) 8202 /* Might end up being a constant function pointer. */; 8203 else 8204 return false; 8205 } 8206 for (; i < nargs; ++i) 8207 { 8208 tree x = get_nth_callarg (t, i); 8209 if (!potential_constant_expression_1 (x, rval, flags)) 8210 return false; 8211 } 8212 return true; 8213 } 8214 8215 case NON_LVALUE_EXPR: 8216 /* -- an lvalue-to-rvalue conversion (4.1) unless it is applied to 8217 -- an lvalue of integral type that refers to a non-volatile 8218 const variable or static data member initialized with 8219 constant expressions, or 8220 8221 -- an lvalue of literal type that refers to non-volatile 8222 object defined with constexpr, or that refers to a 8223 sub-object of such an object; */ 8224 return potential_constant_expression_1 (TREE_OPERAND (t, 0), rval, flags); 8225 8226 case VAR_DECL: 8227 if (want_rval && !decl_constant_var_p (t) 8228 && !dependent_type_p (TREE_TYPE (t))) 8229 { 8230 if (flags & tf_error) 8231 non_const_var_error (t); 8232 return false; 8233 } 8234 return true; 8235 8236 case NOP_EXPR: 8237 case CONVERT_EXPR: 8238 case VIEW_CONVERT_EXPR: 8239 /* -- a reinterpret_cast. FIXME not implemented, and this rule 8240 may change to something more specific to type-punning (DR 1312). */ 8241 { 8242 tree from = TREE_OPERAND (t, 0); 8243 return (potential_constant_expression_1 8244 (from, TREE_CODE (t) != VIEW_CONVERT_EXPR, flags)); 8245 } 8246 8247 case ADDR_EXPR: 8248 /* -- a unary operator & that is applied to an lvalue that 8249 designates an object with thread or automatic storage 8250 duration; */ 8251 t = TREE_OPERAND (t, 0); 8252 #if 0 8253 /* FIXME adjust when issue 1197 is fully resolved. For now don't do 8254 any checking here, as we might dereference the pointer later. If 8255 we remove this code, also remove check_automatic_or_tls. */ 8256 i = check_automatic_or_tls (t); 8257 if (i == ck_ok) 8258 return true; 8259 if (i == ck_bad) 8260 { 8261 if (flags & tf_error) 8262 error ("address-of an object %qE with thread local or " 8263 "automatic storage is not a constant expression", t); 8264 return false; 8265 } 8266 #endif 8267 return potential_constant_expression_1 (t, any, flags); 8268 8269 case COMPONENT_REF: 8270 case BIT_FIELD_REF: 8271 case ARROW_EXPR: 8272 case OFFSET_REF: 8273 /* -- a class member access unless its postfix-expression is 8274 of literal type or of pointer to literal type. */ 8275 /* This test would be redundant, as it follows from the 8276 postfix-expression being a potential constant expression. */ 8277 return potential_constant_expression_1 (TREE_OPERAND (t, 0), 8278 want_rval, flags); 8279 8280 case EXPR_PACK_EXPANSION: 8281 return potential_constant_expression_1 (PACK_EXPANSION_PATTERN (t), 8282 want_rval, flags); 8283 8284 case INDIRECT_REF: 8285 { 8286 tree x = TREE_OPERAND (t, 0); 8287 STRIP_NOPS (x); 8288 if (is_this_parameter (x)) 8289 { 8290 if (want_rval && DECL_CONTEXT (x) 8291 && DECL_CONSTRUCTOR_P (DECL_CONTEXT (x))) 8292 { 8293 if (flags & tf_error) 8294 sorry ("use of the value of the object being constructed " 8295 "in a constant expression"); 8296 return false; 8297 } 8298 return true; 8299 } 8300 return potential_constant_expression_1 (x, rval, flags); 8301 } 8302 8303 case LAMBDA_EXPR: 8304 case DYNAMIC_CAST_EXPR: 8305 case PSEUDO_DTOR_EXPR: 8306 case PREINCREMENT_EXPR: 8307 case POSTINCREMENT_EXPR: 8308 case PREDECREMENT_EXPR: 8309 case POSTDECREMENT_EXPR: 8310 case NEW_EXPR: 8311 case VEC_NEW_EXPR: 8312 case DELETE_EXPR: 8313 case VEC_DELETE_EXPR: 8314 case THROW_EXPR: 8315 case MODIFY_EXPR: 8316 case MODOP_EXPR: 8317 /* GCC internal stuff. */ 8318 case VA_ARG_EXPR: 8319 case OBJ_TYPE_REF: 8320 case WITH_CLEANUP_EXPR: 8321 case CLEANUP_POINT_EXPR: 8322 case MUST_NOT_THROW_EXPR: 8323 case TRY_CATCH_EXPR: 8324 case STATEMENT_LIST: 8325 /* Don't bother trying to define a subset of statement-expressions to 8326 be constant-expressions, at least for now. */ 8327 case STMT_EXPR: 8328 case EXPR_STMT: 8329 case BIND_EXPR: 8330 case TRANSACTION_EXPR: 8331 case IF_STMT: 8332 case DO_STMT: 8333 case FOR_STMT: 8334 case WHILE_STMT: 8335 if (flags & tf_error) 8336 error ("expression %qE is not a constant-expression", t); 8337 return false; 8338 8339 case TYPEID_EXPR: 8340 /* -- a typeid expression whose operand is of polymorphic 8341 class type; */ 8342 { 8343 tree e = TREE_OPERAND (t, 0); 8344 if (!TYPE_P (e) && !type_dependent_expression_p (e) 8345 && TYPE_POLYMORPHIC_P (TREE_TYPE (e))) 8346 { 8347 if (flags & tf_error) 8348 error ("typeid-expression is not a constant expression " 8349 "because %qE is of polymorphic type", e); 8350 return false; 8351 } 8352 return true; 8353 } 8354 8355 case MINUS_EXPR: 8356 /* -- a subtraction where both operands are pointers. */ 8357 if (TYPE_PTR_P (TREE_OPERAND (t, 0)) 8358 && TYPE_PTR_P (TREE_OPERAND (t, 1))) 8359 { 8360 if (flags & tf_error) 8361 error ("difference of two pointer expressions is not " 8362 "a constant expression"); 8363 return false; 8364 } 8365 want_rval = true; 8366 goto binary; 8367 8368 case LT_EXPR: 8369 case LE_EXPR: 8370 case GT_EXPR: 8371 case GE_EXPR: 8372 case EQ_EXPR: 8373 case NE_EXPR: 8374 /* -- a relational or equality operator where at least 8375 one of the operands is a pointer. */ 8376 if (TYPE_PTR_P (TREE_OPERAND (t, 0)) 8377 || TYPE_PTR_P (TREE_OPERAND (t, 1))) 8378 { 8379 if (flags & tf_error) 8380 error ("pointer comparison expression is not a " 8381 "constant expression"); 8382 return false; 8383 } 8384 want_rval = true; 8385 goto binary; 8386 8387 case BIT_NOT_EXPR: 8388 /* A destructor. */ 8389 if (TYPE_P (TREE_OPERAND (t, 0))) 8390 return true; 8391 /* else fall through. */ 8392 8393 case REALPART_EXPR: 8394 case IMAGPART_EXPR: 8395 case CONJ_EXPR: 8396 case SAVE_EXPR: 8397 case FIX_TRUNC_EXPR: 8398 case FLOAT_EXPR: 8399 case NEGATE_EXPR: 8400 case ABS_EXPR: 8401 case TRUTH_NOT_EXPR: 8402 case FIXED_CONVERT_EXPR: 8403 case UNARY_PLUS_EXPR: 8404 return potential_constant_expression_1 (TREE_OPERAND (t, 0), rval, 8405 flags); 8406 8407 case CAST_EXPR: 8408 case CONST_CAST_EXPR: 8409 case STATIC_CAST_EXPR: 8410 case REINTERPRET_CAST_EXPR: 8411 case IMPLICIT_CONV_EXPR: 8412 return (potential_constant_expression_1 8413 (TREE_OPERAND (t, 0), 8414 TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE, flags)); 8415 8416 case PAREN_EXPR: 8417 case NON_DEPENDENT_EXPR: 8418 /* For convenience. */ 8419 case RETURN_EXPR: 8420 return potential_constant_expression_1 (TREE_OPERAND (t, 0), 8421 want_rval, flags); 8422 8423 case SCOPE_REF: 8424 return potential_constant_expression_1 (TREE_OPERAND (t, 1), 8425 want_rval, flags); 8426 8427 case TARGET_EXPR: 8428 if (!literal_type_p (TREE_TYPE (t))) 8429 { 8430 if (flags & tf_error) 8431 { 8432 error ("temporary of non-literal type %qT in a " 8433 "constant expression", TREE_TYPE (t)); 8434 explain_non_literal_class (TREE_TYPE (t)); 8435 } 8436 return false; 8437 } 8438 case INIT_EXPR: 8439 return potential_constant_expression_1 (TREE_OPERAND (t, 1), 8440 rval, flags); 8441 8442 case CONSTRUCTOR: 8443 { 8444 VEC(constructor_elt, gc) *v = CONSTRUCTOR_ELTS (t); 8445 constructor_elt *ce; 8446 for (i = 0; VEC_iterate (constructor_elt, v, i, ce); ++i) 8447 if (!potential_constant_expression_1 (ce->value, want_rval, flags)) 8448 return false; 8449 return true; 8450 } 8451 8452 case TREE_LIST: 8453 { 8454 gcc_assert (TREE_PURPOSE (t) == NULL_TREE 8455 || DECL_P (TREE_PURPOSE (t))); 8456 if (!potential_constant_expression_1 (TREE_VALUE (t), want_rval, 8457 flags)) 8458 return false; 8459 if (TREE_CHAIN (t) == NULL_TREE) 8460 return true; 8461 return potential_constant_expression_1 (TREE_CHAIN (t), want_rval, 8462 flags); 8463 } 8464 8465 case TRUNC_DIV_EXPR: 8466 case CEIL_DIV_EXPR: 8467 case FLOOR_DIV_EXPR: 8468 case ROUND_DIV_EXPR: 8469 case TRUNC_MOD_EXPR: 8470 case CEIL_MOD_EXPR: 8471 case ROUND_MOD_EXPR: 8472 { 8473 tree denom = TREE_OPERAND (t, 1); 8474 /* We can't call maybe_constant_value on an expression 8475 that hasn't been through fold_non_dependent_expr yet. */ 8476 if (!processing_template_decl) 8477 denom = maybe_constant_value (denom); 8478 if (integer_zerop (denom)) 8479 { 8480 if (flags & tf_error) 8481 error ("division by zero is not a constant-expression"); 8482 return false; 8483 } 8484 else 8485 { 8486 want_rval = true; 8487 goto binary; 8488 } 8489 } 8490 8491 case COMPOUND_EXPR: 8492 { 8493 /* check_return_expr sometimes wraps a TARGET_EXPR in a 8494 COMPOUND_EXPR; don't get confused. Also handle EMPTY_CLASS_EXPR 8495 introduced by build_call_a. */ 8496 tree op0 = TREE_OPERAND (t, 0); 8497 tree op1 = TREE_OPERAND (t, 1); 8498 STRIP_NOPS (op1); 8499 if ((TREE_CODE (op0) == TARGET_EXPR && op1 == TARGET_EXPR_SLOT (op0)) 8500 || TREE_CODE (op1) == EMPTY_CLASS_EXPR) 8501 return potential_constant_expression_1 (op0, want_rval, flags); 8502 else 8503 goto binary; 8504 } 8505 8506 /* If the first operand is the non-short-circuit constant, look at 8507 the second operand; otherwise we only care about the first one for 8508 potentiality. */ 8509 case TRUTH_AND_EXPR: 8510 case TRUTH_ANDIF_EXPR: 8511 tmp = boolean_true_node; 8512 goto truth; 8513 case TRUTH_OR_EXPR: 8514 case TRUTH_ORIF_EXPR: 8515 tmp = boolean_false_node; 8516 truth: 8517 if (TREE_OPERAND (t, 0) == tmp) 8518 return potential_constant_expression_1 (TREE_OPERAND (t, 1), rval, flags); 8519 else 8520 return potential_constant_expression_1 (TREE_OPERAND (t, 0), rval, flags); 8521 8522 case PLUS_EXPR: 8523 case MULT_EXPR: 8524 case POINTER_PLUS_EXPR: 8525 case RDIV_EXPR: 8526 case EXACT_DIV_EXPR: 8527 case MIN_EXPR: 8528 case MAX_EXPR: 8529 case LSHIFT_EXPR: 8530 case RSHIFT_EXPR: 8531 case LROTATE_EXPR: 8532 case RROTATE_EXPR: 8533 case BIT_IOR_EXPR: 8534 case BIT_XOR_EXPR: 8535 case BIT_AND_EXPR: 8536 case TRUTH_XOR_EXPR: 8537 case UNORDERED_EXPR: 8538 case ORDERED_EXPR: 8539 case UNLT_EXPR: 8540 case UNLE_EXPR: 8541 case UNGT_EXPR: 8542 case UNGE_EXPR: 8543 case UNEQ_EXPR: 8544 case LTGT_EXPR: 8545 case RANGE_EXPR: 8546 case COMPLEX_EXPR: 8547 want_rval = true; 8548 /* Fall through. */ 8549 case ARRAY_REF: 8550 case ARRAY_RANGE_REF: 8551 case MEMBER_REF: 8552 case DOTSTAR_EXPR: 8553 binary: 8554 for (i = 0; i < 2; ++i) 8555 if (!potential_constant_expression_1 (TREE_OPERAND (t, i), 8556 want_rval, flags)) 8557 return false; 8558 return true; 8559 8560 case FMA_EXPR: 8561 for (i = 0; i < 3; ++i) 8562 if (!potential_constant_expression_1 (TREE_OPERAND (t, i), 8563 true, flags)) 8564 return false; 8565 return true; 8566 8567 case COND_EXPR: 8568 case VEC_COND_EXPR: 8569 /* If the condition is a known constant, we know which of the legs we 8570 care about; otherwise we only require that the condition and 8571 either of the legs be potentially constant. */ 8572 tmp = TREE_OPERAND (t, 0); 8573 if (!potential_constant_expression_1 (tmp, rval, flags)) 8574 return false; 8575 else if (integer_zerop (tmp)) 8576 return potential_constant_expression_1 (TREE_OPERAND (t, 2), 8577 want_rval, flags); 8578 else if (TREE_CODE (tmp) == INTEGER_CST) 8579 return potential_constant_expression_1 (TREE_OPERAND (t, 1), 8580 want_rval, flags); 8581 for (i = 1; i < 3; ++i) 8582 if (potential_constant_expression_1 (TREE_OPERAND (t, i), 8583 want_rval, tf_none)) 8584 return true; 8585 if (flags & tf_error) 8586 error ("expression %qE is not a constant-expression", t); 8587 return false; 8588 8589 case VEC_INIT_EXPR: 8590 if (VEC_INIT_EXPR_IS_CONSTEXPR (t)) 8591 return true; 8592 if (flags & tf_error) 8593 { 8594 error ("non-constant array initialization"); 8595 diagnose_non_constexpr_vec_init (t); 8596 } 8597 return false; 8598 8599 default: 8600 sorry ("unexpected AST of kind %s", tree_code_name[TREE_CODE (t)]); 8601 gcc_unreachable(); 8602 return false; 8603 } 8604 } 8605 8606 /* The main entry point to the above. */ 8607 8608 bool 8609 potential_constant_expression (tree t) 8610 { 8611 return potential_constant_expression_1 (t, false, tf_none); 8612 } 8613 8614 /* As above, but require a constant rvalue. */ 8615 8616 bool 8617 potential_rvalue_constant_expression (tree t) 8618 { 8619 return potential_constant_expression_1 (t, true, tf_none); 8620 } 8621 8622 /* Like above, but complain about non-constant expressions. */ 8623 8624 bool 8625 require_potential_constant_expression (tree t) 8626 { 8627 return potential_constant_expression_1 (t, false, tf_warning_or_error); 8628 } 8629 8630 /* Cross product of the above. */ 8631 8632 bool 8633 require_potential_rvalue_constant_expression (tree t) 8634 { 8635 return potential_constant_expression_1 (t, true, tf_warning_or_error); 8636 } 8637 8638 /* Constructor for a lambda expression. */ 8639 8640 tree 8641 build_lambda_expr (void) 8642 { 8643 tree lambda = make_node (LAMBDA_EXPR); 8644 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda) = CPLD_NONE; 8645 LAMBDA_EXPR_CAPTURE_LIST (lambda) = NULL_TREE; 8646 LAMBDA_EXPR_THIS_CAPTURE (lambda) = NULL_TREE; 8647 LAMBDA_EXPR_PENDING_PROXIES (lambda) = NULL; 8648 LAMBDA_EXPR_RETURN_TYPE (lambda) = NULL_TREE; 8649 LAMBDA_EXPR_MUTABLE_P (lambda) = false; 8650 return lambda; 8651 } 8652 8653 /* Create the closure object for a LAMBDA_EXPR. */ 8654 8655 tree 8656 build_lambda_object (tree lambda_expr) 8657 { 8658 /* Build aggregate constructor call. 8659 - cp_parser_braced_list 8660 - cp_parser_functional_cast */ 8661 VEC(constructor_elt,gc) *elts = NULL; 8662 tree node, expr, type; 8663 location_t saved_loc; 8664 8665 if (processing_template_decl) 8666 return lambda_expr; 8667 8668 /* Make sure any error messages refer to the lambda-introducer. */ 8669 saved_loc = input_location; 8670 input_location = LAMBDA_EXPR_LOCATION (lambda_expr); 8671 8672 for (node = LAMBDA_EXPR_CAPTURE_LIST (lambda_expr); 8673 node; 8674 node = TREE_CHAIN (node)) 8675 { 8676 tree field = TREE_PURPOSE (node); 8677 tree val = TREE_VALUE (node); 8678 8679 if (field == error_mark_node) 8680 { 8681 expr = error_mark_node; 8682 goto out; 8683 } 8684 8685 if (DECL_P (val)) 8686 mark_used (val); 8687 8688 /* Mere mortals can't copy arrays with aggregate initialization, so 8689 do some magic to make it work here. */ 8690 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE) 8691 val = build_array_copy (val); 8692 else if (DECL_NORMAL_CAPTURE_P (field) 8693 && TREE_CODE (TREE_TYPE (field)) != REFERENCE_TYPE) 8694 { 8695 /* "the entities that are captured by copy are used to 8696 direct-initialize each corresponding non-static data 8697 member of the resulting closure object." 8698 8699 There's normally no way to express direct-initialization 8700 from an element of a CONSTRUCTOR, so we build up a special 8701 TARGET_EXPR to bypass the usual copy-initialization. */ 8702 val = force_rvalue (val, tf_warning_or_error); 8703 if (TREE_CODE (val) == TARGET_EXPR) 8704 TARGET_EXPR_DIRECT_INIT_P (val) = true; 8705 } 8706 8707 CONSTRUCTOR_APPEND_ELT (elts, DECL_NAME (field), val); 8708 } 8709 8710 expr = build_constructor (init_list_type_node, elts); 8711 CONSTRUCTOR_IS_DIRECT_INIT (expr) = 1; 8712 8713 /* N2927: "[The closure] class type is not an aggregate." 8714 But we briefly treat it as an aggregate to make this simpler. */ 8715 type = LAMBDA_EXPR_CLOSURE (lambda_expr); 8716 CLASSTYPE_NON_AGGREGATE (type) = 0; 8717 expr = finish_compound_literal (type, expr, tf_warning_or_error); 8718 CLASSTYPE_NON_AGGREGATE (type) = 1; 8719 8720 out: 8721 input_location = saved_loc; 8722 return expr; 8723 } 8724 8725 /* Return an initialized RECORD_TYPE for LAMBDA. 8726 LAMBDA must have its explicit captures already. */ 8727 8728 tree 8729 begin_lambda_type (tree lambda) 8730 { 8731 tree type; 8732 8733 { 8734 /* Unique name. This is just like an unnamed class, but we cannot use 8735 make_anon_name because of certain checks against TYPE_ANONYMOUS_P. */ 8736 tree name; 8737 name = make_lambda_name (); 8738 8739 /* Create the new RECORD_TYPE for this lambda. */ 8740 type = xref_tag (/*tag_code=*/record_type, 8741 name, 8742 /*scope=*/ts_within_enclosing_non_class, 8743 /*template_header_p=*/false); 8744 } 8745 8746 /* Designate it as a struct so that we can use aggregate initialization. */ 8747 CLASSTYPE_DECLARED_CLASS (type) = false; 8748 8749 /* Clear base types. */ 8750 xref_basetypes (type, /*bases=*/NULL_TREE); 8751 8752 /* Start the class. */ 8753 type = begin_class_definition (type); 8754 if (type == error_mark_node) 8755 return error_mark_node; 8756 8757 /* Cross-reference the expression and the type. */ 8758 LAMBDA_EXPR_CLOSURE (lambda) = type; 8759 CLASSTYPE_LAMBDA_EXPR (type) = lambda; 8760 8761 return type; 8762 } 8763 8764 /* Returns the type to use for the return type of the operator() of a 8765 closure class. */ 8766 8767 tree 8768 lambda_return_type (tree expr) 8769 { 8770 tree type; 8771 if (type_unknown_p (expr) 8772 || BRACE_ENCLOSED_INITIALIZER_P (expr)) 8773 { 8774 cxx_incomplete_type_error (expr, TREE_TYPE (expr)); 8775 return void_type_node; 8776 } 8777 if (type_dependent_expression_p (expr)) 8778 type = dependent_lambda_return_type_node; 8779 else 8780 type = cv_unqualified (type_decays_to (unlowered_expr_type (expr))); 8781 return type; 8782 } 8783 8784 /* Given a LAMBDA_EXPR or closure type LAMBDA, return the op() of the 8785 closure type. */ 8786 8787 tree 8788 lambda_function (tree lambda) 8789 { 8790 tree type; 8791 if (TREE_CODE (lambda) == LAMBDA_EXPR) 8792 type = LAMBDA_EXPR_CLOSURE (lambda); 8793 else 8794 type = lambda; 8795 gcc_assert (LAMBDA_TYPE_P (type)); 8796 /* Don't let debug_tree cause instantiation. */ 8797 if (CLASSTYPE_TEMPLATE_INSTANTIATION (type) 8798 && !COMPLETE_OR_OPEN_TYPE_P (type)) 8799 return NULL_TREE; 8800 lambda = lookup_member (type, ansi_opname (CALL_EXPR), 8801 /*protect=*/0, /*want_type=*/false, 8802 tf_warning_or_error); 8803 if (lambda) 8804 lambda = BASELINK_FUNCTIONS (lambda); 8805 return lambda; 8806 } 8807 8808 /* Returns the type to use for the FIELD_DECL corresponding to the 8809 capture of EXPR. 8810 The caller should add REFERENCE_TYPE for capture by reference. */ 8811 8812 tree 8813 lambda_capture_field_type (tree expr) 8814 { 8815 tree type; 8816 if (type_dependent_expression_p (expr) 8817 && !(TREE_TYPE (expr) && TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)) 8818 { 8819 type = cxx_make_type (DECLTYPE_TYPE); 8820 DECLTYPE_TYPE_EXPR (type) = expr; 8821 DECLTYPE_FOR_LAMBDA_CAPTURE (type) = true; 8822 SET_TYPE_STRUCTURAL_EQUALITY (type); 8823 } 8824 else 8825 type = non_reference (unlowered_expr_type (expr)); 8826 return type; 8827 } 8828 8829 /* Recompute the return type for LAMBDA with body of the form: 8830 { return EXPR ; } */ 8831 8832 void 8833 apply_lambda_return_type (tree lambda, tree return_type) 8834 { 8835 tree fco = lambda_function (lambda); 8836 tree result; 8837 8838 LAMBDA_EXPR_RETURN_TYPE (lambda) = return_type; 8839 8840 if (return_type == error_mark_node) 8841 return; 8842 if (TREE_TYPE (TREE_TYPE (fco)) == return_type) 8843 return; 8844 8845 /* TREE_TYPE (FUNCTION_DECL) == METHOD_TYPE 8846 TREE_TYPE (METHOD_TYPE) == return-type */ 8847 TREE_TYPE (fco) = change_return_type (return_type, TREE_TYPE (fco)); 8848 8849 result = DECL_RESULT (fco); 8850 if (result == NULL_TREE) 8851 return; 8852 8853 /* We already have a DECL_RESULT from start_preparsed_function. 8854 Now we need to redo the work it and allocate_struct_function 8855 did to reflect the new type. */ 8856 gcc_assert (current_function_decl == fco); 8857 result = build_decl (input_location, RESULT_DECL, NULL_TREE, 8858 TYPE_MAIN_VARIANT (return_type)); 8859 DECL_ARTIFICIAL (result) = 1; 8860 DECL_IGNORED_P (result) = 1; 8861 cp_apply_type_quals_to_decl (cp_type_quals (return_type), 8862 result); 8863 8864 DECL_RESULT (fco) = result; 8865 8866 if (!processing_template_decl && aggregate_value_p (result, fco)) 8867 { 8868 #ifdef PCC_STATIC_STRUCT_RETURN 8869 cfun->returns_pcc_struct = 1; 8870 #endif 8871 cfun->returns_struct = 1; 8872 } 8873 8874 } 8875 8876 /* DECL is a local variable or parameter from the surrounding scope of a 8877 lambda-expression. Returns the decltype for a use of the capture field 8878 for DECL even if it hasn't been captured yet. */ 8879 8880 static tree 8881 capture_decltype (tree decl) 8882 { 8883 tree lam = CLASSTYPE_LAMBDA_EXPR (DECL_CONTEXT (current_function_decl)); 8884 /* FIXME do lookup instead of list walk? */ 8885 tree cap = value_member (decl, LAMBDA_EXPR_CAPTURE_LIST (lam)); 8886 tree type; 8887 8888 if (cap) 8889 type = TREE_TYPE (TREE_PURPOSE (cap)); 8890 else 8891 switch (LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lam)) 8892 { 8893 case CPLD_NONE: 8894 error ("%qD is not captured", decl); 8895 return error_mark_node; 8896 8897 case CPLD_COPY: 8898 type = TREE_TYPE (decl); 8899 if (TREE_CODE (type) == REFERENCE_TYPE 8900 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE) 8901 type = TREE_TYPE (type); 8902 break; 8903 8904 case CPLD_REFERENCE: 8905 type = TREE_TYPE (decl); 8906 if (TREE_CODE (type) != REFERENCE_TYPE) 8907 type = build_reference_type (TREE_TYPE (decl)); 8908 break; 8909 8910 default: 8911 gcc_unreachable (); 8912 } 8913 8914 if (TREE_CODE (type) != REFERENCE_TYPE) 8915 { 8916 if (!LAMBDA_EXPR_MUTABLE_P (lam)) 8917 type = cp_build_qualified_type (type, (cp_type_quals (type) 8918 |TYPE_QUAL_CONST)); 8919 type = build_reference_type (type); 8920 } 8921 return type; 8922 } 8923 8924 /* Returns true iff DECL is a lambda capture proxy variable created by 8925 build_capture_proxy. */ 8926 8927 bool 8928 is_capture_proxy (tree decl) 8929 { 8930 return (TREE_CODE (decl) == VAR_DECL 8931 && DECL_HAS_VALUE_EXPR_P (decl) 8932 && !DECL_ANON_UNION_VAR_P (decl) 8933 && LAMBDA_FUNCTION_P (DECL_CONTEXT (decl))); 8934 } 8935 8936 /* Returns true iff DECL is a capture proxy for a normal capture 8937 (i.e. without explicit initializer). */ 8938 8939 bool 8940 is_normal_capture_proxy (tree decl) 8941 { 8942 tree val; 8943 8944 if (!is_capture_proxy (decl)) 8945 /* It's not a capture proxy. */ 8946 return false; 8947 8948 /* It is a capture proxy, is it a normal capture? */ 8949 val = DECL_VALUE_EXPR (decl); 8950 gcc_assert (TREE_CODE (val) == COMPONENT_REF); 8951 val = TREE_OPERAND (val, 1); 8952 return DECL_NORMAL_CAPTURE_P (val); 8953 } 8954 8955 /* VAR is a capture proxy created by build_capture_proxy; add it to the 8956 current function, which is the operator() for the appropriate lambda. */ 8957 8958 void 8959 insert_capture_proxy (tree var) 8960 { 8961 cp_binding_level *b; 8962 int skip; 8963 tree stmt_list; 8964 8965 /* Put the capture proxy in the extra body block so that it won't clash 8966 with a later local variable. */ 8967 b = current_binding_level; 8968 for (skip = 0; ; ++skip) 8969 { 8970 cp_binding_level *n = b->level_chain; 8971 if (n->kind == sk_function_parms) 8972 break; 8973 b = n; 8974 } 8975 pushdecl_with_scope (var, b, false); 8976 8977 /* And put a DECL_EXPR in the STATEMENT_LIST for the same block. */ 8978 var = build_stmt (DECL_SOURCE_LOCATION (var), DECL_EXPR, var); 8979 stmt_list = VEC_index (tree, stmt_list_stack, 8980 VEC_length (tree, stmt_list_stack) - 1 - skip); 8981 gcc_assert (stmt_list); 8982 append_to_statement_list_force (var, &stmt_list); 8983 } 8984 8985 /* We've just finished processing a lambda; if the containing scope is also 8986 a lambda, insert any capture proxies that were created while processing 8987 the nested lambda. */ 8988 8989 void 8990 insert_pending_capture_proxies (void) 8991 { 8992 tree lam; 8993 VEC(tree,gc) *proxies; 8994 unsigned i; 8995 8996 if (!current_function_decl || !LAMBDA_FUNCTION_P (current_function_decl)) 8997 return; 8998 8999 lam = CLASSTYPE_LAMBDA_EXPR (DECL_CONTEXT (current_function_decl)); 9000 proxies = LAMBDA_EXPR_PENDING_PROXIES (lam); 9001 for (i = 0; i < VEC_length (tree, proxies); ++i) 9002 { 9003 tree var = VEC_index (tree, proxies, i); 9004 insert_capture_proxy (var); 9005 } 9006 release_tree_vector (LAMBDA_EXPR_PENDING_PROXIES (lam)); 9007 LAMBDA_EXPR_PENDING_PROXIES (lam) = NULL; 9008 } 9009 9010 /* Given REF, a COMPONENT_REF designating a field in the lambda closure, 9011 return the type we want the proxy to have: the type of the field itself, 9012 with added const-qualification if the lambda isn't mutable and the 9013 capture is by value. */ 9014 9015 tree 9016 lambda_proxy_type (tree ref) 9017 { 9018 tree type; 9019 if (REFERENCE_REF_P (ref)) 9020 ref = TREE_OPERAND (ref, 0); 9021 type = TREE_TYPE (ref); 9022 if (!dependent_type_p (type) 9023 || (type && TREE_CODE (type) == POINTER_TYPE)) 9024 return type; 9025 type = cxx_make_type (DECLTYPE_TYPE); 9026 DECLTYPE_TYPE_EXPR (type) = ref; 9027 DECLTYPE_FOR_LAMBDA_PROXY (type) = true; 9028 SET_TYPE_STRUCTURAL_EQUALITY (type); 9029 return type; 9030 } 9031 9032 /* MEMBER is a capture field in a lambda closure class. Now that we're 9033 inside the operator(), build a placeholder var for future lookups and 9034 debugging. */ 9035 9036 tree 9037 build_capture_proxy (tree member) 9038 { 9039 tree var, object, fn, closure, name, lam, type; 9040 9041 closure = DECL_CONTEXT (member); 9042 fn = lambda_function (closure); 9043 lam = CLASSTYPE_LAMBDA_EXPR (closure); 9044 9045 /* The proxy variable forwards to the capture field. */ 9046 object = build_fold_indirect_ref (DECL_ARGUMENTS (fn)); 9047 object = finish_non_static_data_member (member, object, NULL_TREE); 9048 if (REFERENCE_REF_P (object)) 9049 object = TREE_OPERAND (object, 0); 9050 9051 /* Remove the __ inserted by add_capture. */ 9052 name = get_identifier (IDENTIFIER_POINTER (DECL_NAME (member)) + 2); 9053 9054 type = lambda_proxy_type (object); 9055 var = build_decl (input_location, VAR_DECL, name, type); 9056 SET_DECL_VALUE_EXPR (var, object); 9057 DECL_HAS_VALUE_EXPR_P (var) = 1; 9058 DECL_ARTIFICIAL (var) = 1; 9059 TREE_USED (var) = 1; 9060 DECL_CONTEXT (var) = fn; 9061 9062 if (name == this_identifier) 9063 { 9064 gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (lam) == member); 9065 LAMBDA_EXPR_THIS_CAPTURE (lam) = var; 9066 } 9067 9068 if (fn == current_function_decl) 9069 insert_capture_proxy (var); 9070 else 9071 VEC_safe_push (tree, gc, LAMBDA_EXPR_PENDING_PROXIES (lam), var); 9072 9073 return var; 9074 } 9075 9076 /* From an ID and INITIALIZER, create a capture (by reference if 9077 BY_REFERENCE_P is true), add it to the capture-list for LAMBDA, 9078 and return it. */ 9079 9080 tree 9081 add_capture (tree lambda, tree id, tree initializer, bool by_reference_p, 9082 bool explicit_init_p) 9083 { 9084 char *buf; 9085 tree type, member, name; 9086 9087 type = lambda_capture_field_type (initializer); 9088 if (by_reference_p) 9089 { 9090 type = build_reference_type (type); 9091 if (!real_lvalue_p (initializer)) 9092 error ("cannot capture %qE by reference", initializer); 9093 } 9094 else 9095 /* Capture by copy requires a complete type. */ 9096 type = complete_type (type); 9097 9098 /* Add __ to the beginning of the field name so that user code 9099 won't find the field with name lookup. We can't just leave the name 9100 unset because template instantiation uses the name to find 9101 instantiated fields. */ 9102 buf = (char *) alloca (IDENTIFIER_LENGTH (id) + 3); 9103 buf[1] = buf[0] = '_'; 9104 memcpy (buf + 2, IDENTIFIER_POINTER (id), 9105 IDENTIFIER_LENGTH (id) + 1); 9106 name = get_identifier (buf); 9107 9108 /* If TREE_TYPE isn't set, we're still in the introducer, so check 9109 for duplicates. */ 9110 if (!LAMBDA_EXPR_CLOSURE (lambda)) 9111 { 9112 if (IDENTIFIER_MARKED (name)) 9113 { 9114 pedwarn (input_location, 0, 9115 "already captured %qD in lambda expression", id); 9116 return NULL_TREE; 9117 } 9118 IDENTIFIER_MARKED (name) = true; 9119 } 9120 9121 /* Make member variable. */ 9122 member = build_lang_decl (FIELD_DECL, name, type); 9123 9124 if (!explicit_init_p) 9125 /* Normal captures are invisible to name lookup but uses are replaced 9126 with references to the capture field; we implement this by only 9127 really making them invisible in unevaluated context; see 9128 qualify_lookup. For now, let's make explicitly initialized captures 9129 always visible. */ 9130 DECL_NORMAL_CAPTURE_P (member) = true; 9131 9132 if (id == this_identifier) 9133 LAMBDA_EXPR_THIS_CAPTURE (lambda) = member; 9134 9135 /* Add it to the appropriate closure class if we've started it. */ 9136 if (current_class_type 9137 && current_class_type == LAMBDA_EXPR_CLOSURE (lambda)) 9138 finish_member_declaration (member); 9139 9140 LAMBDA_EXPR_CAPTURE_LIST (lambda) 9141 = tree_cons (member, initializer, LAMBDA_EXPR_CAPTURE_LIST (lambda)); 9142 9143 if (LAMBDA_EXPR_CLOSURE (lambda)) 9144 return build_capture_proxy (member); 9145 /* For explicit captures we haven't started the function yet, so we wait 9146 and build the proxy from cp_parser_lambda_body. */ 9147 return NULL_TREE; 9148 } 9149 9150 /* Register all the capture members on the list CAPTURES, which is the 9151 LAMBDA_EXPR_CAPTURE_LIST for the lambda after the introducer. */ 9152 9153 void 9154 register_capture_members (tree captures) 9155 { 9156 if (captures == NULL_TREE) 9157 return; 9158 9159 register_capture_members (TREE_CHAIN (captures)); 9160 /* We set this in add_capture to avoid duplicates. */ 9161 IDENTIFIER_MARKED (DECL_NAME (TREE_PURPOSE (captures))) = false; 9162 finish_member_declaration (TREE_PURPOSE (captures)); 9163 } 9164 9165 /* Similar to add_capture, except this works on a stack of nested lambdas. 9166 BY_REFERENCE_P in this case is derived from the default capture mode. 9167 Returns the capture for the lambda at the bottom of the stack. */ 9168 9169 tree 9170 add_default_capture (tree lambda_stack, tree id, tree initializer) 9171 { 9172 bool this_capture_p = (id == this_identifier); 9173 9174 tree var = NULL_TREE; 9175 9176 tree saved_class_type = current_class_type; 9177 9178 tree node; 9179 9180 for (node = lambda_stack; 9181 node; 9182 node = TREE_CHAIN (node)) 9183 { 9184 tree lambda = TREE_VALUE (node); 9185 9186 current_class_type = LAMBDA_EXPR_CLOSURE (lambda); 9187 var = add_capture (lambda, 9188 id, 9189 initializer, 9190 /*by_reference_p=*/ 9191 (!this_capture_p 9192 && (LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda) 9193 == CPLD_REFERENCE)), 9194 /*explicit_init_p=*/false); 9195 initializer = convert_from_reference (var); 9196 } 9197 9198 current_class_type = saved_class_type; 9199 9200 return var; 9201 } 9202 9203 /* Return the capture pertaining to a use of 'this' in LAMBDA, in the form of an 9204 INDIRECT_REF, possibly adding it through default capturing. */ 9205 9206 tree 9207 lambda_expr_this_capture (tree lambda) 9208 { 9209 tree result; 9210 9211 tree this_capture = LAMBDA_EXPR_THIS_CAPTURE (lambda); 9212 9213 /* Try to default capture 'this' if we can. */ 9214 if (!this_capture 9215 && LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda) != CPLD_NONE) 9216 { 9217 tree containing_function = TYPE_CONTEXT (LAMBDA_EXPR_CLOSURE (lambda)); 9218 tree lambda_stack = tree_cons (NULL_TREE, lambda, NULL_TREE); 9219 tree init = NULL_TREE; 9220 9221 /* If we are in a lambda function, we can move out until we hit: 9222 1. a non-lambda function, 9223 2. a lambda function capturing 'this', or 9224 3. a non-default capturing lambda function. */ 9225 while (LAMBDA_FUNCTION_P (containing_function)) 9226 { 9227 tree lambda 9228 = CLASSTYPE_LAMBDA_EXPR (DECL_CONTEXT (containing_function)); 9229 9230 if (LAMBDA_EXPR_THIS_CAPTURE (lambda)) 9231 { 9232 /* An outer lambda has already captured 'this'. */ 9233 init = LAMBDA_EXPR_THIS_CAPTURE (lambda); 9234 break; 9235 } 9236 9237 if (LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda) == CPLD_NONE) 9238 /* An outer lambda won't let us capture 'this'. */ 9239 break; 9240 9241 lambda_stack = tree_cons (NULL_TREE, 9242 lambda, 9243 lambda_stack); 9244 9245 containing_function = decl_function_context (containing_function); 9246 } 9247 9248 if (!init && DECL_NONSTATIC_MEMBER_FUNCTION_P (containing_function) 9249 && !LAMBDA_FUNCTION_P (containing_function)) 9250 /* First parameter is 'this'. */ 9251 init = DECL_ARGUMENTS (containing_function); 9252 9253 if (init) 9254 this_capture = add_default_capture (lambda_stack, 9255 /*id=*/this_identifier, 9256 init); 9257 } 9258 9259 if (!this_capture) 9260 { 9261 error ("%<this%> was not captured for this lambda function"); 9262 result = error_mark_node; 9263 } 9264 else 9265 { 9266 /* To make sure that current_class_ref is for the lambda. */ 9267 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (current_class_ref)) 9268 == LAMBDA_EXPR_CLOSURE (lambda)); 9269 9270 result = this_capture; 9271 9272 /* If 'this' is captured, each use of 'this' is transformed into an 9273 access to the corresponding unnamed data member of the closure 9274 type cast (_expr.cast_ 5.4) to the type of 'this'. [ The cast 9275 ensures that the transformed expression is an rvalue. ] */ 9276 result = rvalue (result); 9277 } 9278 9279 return result; 9280 } 9281 9282 /* Returns the method basetype of the innermost non-lambda function, or 9283 NULL_TREE if none. */ 9284 9285 tree 9286 nonlambda_method_basetype (void) 9287 { 9288 tree fn, type; 9289 if (!current_class_ref) 9290 return NULL_TREE; 9291 9292 type = current_class_type; 9293 if (!LAMBDA_TYPE_P (type)) 9294 return type; 9295 9296 /* Find the nearest enclosing non-lambda function. */ 9297 fn = TYPE_NAME (type); 9298 do 9299 fn = decl_function_context (fn); 9300 while (fn && LAMBDA_FUNCTION_P (fn)); 9301 9302 if (!fn || !DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)) 9303 return NULL_TREE; 9304 9305 return TYPE_METHOD_BASETYPE (TREE_TYPE (fn)); 9306 } 9307 9308 /* If the closure TYPE has a static op(), also add a conversion to function 9309 pointer. */ 9310 9311 void 9312 maybe_add_lambda_conv_op (tree type) 9313 { 9314 bool nested = (current_function_decl != NULL_TREE); 9315 tree callop = lambda_function (type); 9316 tree rettype, name, fntype, fn, body, compound_stmt; 9317 tree thistype, stattype, statfn, convfn, call, arg; 9318 VEC (tree, gc) *argvec; 9319 9320 if (LAMBDA_EXPR_CAPTURE_LIST (CLASSTYPE_LAMBDA_EXPR (type)) != NULL_TREE) 9321 return; 9322 9323 if (processing_template_decl) 9324 return; 9325 9326 stattype = build_function_type (TREE_TYPE (TREE_TYPE (callop)), 9327 FUNCTION_ARG_CHAIN (callop)); 9328 9329 /* First build up the conversion op. */ 9330 9331 rettype = build_pointer_type (stattype); 9332 name = mangle_conv_op_name_for_type (rettype); 9333 thistype = cp_build_qualified_type (type, TYPE_QUAL_CONST); 9334 fntype = build_method_type_directly (thistype, rettype, void_list_node); 9335 fn = convfn = build_lang_decl (FUNCTION_DECL, name, fntype); 9336 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (callop); 9337 9338 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_pfn 9339 && DECL_ALIGN (fn) < 2 * BITS_PER_UNIT) 9340 DECL_ALIGN (fn) = 2 * BITS_PER_UNIT; 9341 9342 SET_OVERLOADED_OPERATOR_CODE (fn, TYPE_EXPR); 9343 grokclassfn (type, fn, NO_SPECIAL); 9344 set_linkage_according_to_type (type, fn); 9345 rest_of_decl_compilation (fn, toplevel_bindings_p (), at_eof); 9346 DECL_IN_AGGR_P (fn) = 1; 9347 DECL_ARTIFICIAL (fn) = 1; 9348 DECL_NOT_REALLY_EXTERN (fn) = 1; 9349 DECL_DECLARED_INLINE_P (fn) = 1; 9350 DECL_ARGUMENTS (fn) = build_this_parm (fntype, TYPE_QUAL_CONST); 9351 if (nested) 9352 DECL_INTERFACE_KNOWN (fn) = 1; 9353 9354 add_method (type, fn, NULL_TREE); 9355 9356 /* Generic thunk code fails for varargs; we'll complain in mark_used if 9357 the conversion op is used. */ 9358 if (varargs_function_p (callop)) 9359 { 9360 DECL_DELETED_FN (fn) = 1; 9361 return; 9362 } 9363 9364 /* Now build up the thunk to be returned. */ 9365 9366 name = get_identifier ("_FUN"); 9367 fn = statfn = build_lang_decl (FUNCTION_DECL, name, stattype); 9368 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (callop); 9369 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_pfn 9370 && DECL_ALIGN (fn) < 2 * BITS_PER_UNIT) 9371 DECL_ALIGN (fn) = 2 * BITS_PER_UNIT; 9372 grokclassfn (type, fn, NO_SPECIAL); 9373 set_linkage_according_to_type (type, fn); 9374 rest_of_decl_compilation (fn, toplevel_bindings_p (), at_eof); 9375 DECL_IN_AGGR_P (fn) = 1; 9376 DECL_ARTIFICIAL (fn) = 1; 9377 DECL_NOT_REALLY_EXTERN (fn) = 1; 9378 DECL_DECLARED_INLINE_P (fn) = 1; 9379 DECL_STATIC_FUNCTION_P (fn) = 1; 9380 DECL_ARGUMENTS (fn) = copy_list (DECL_CHAIN (DECL_ARGUMENTS (callop))); 9381 for (arg = DECL_ARGUMENTS (fn); arg; arg = DECL_CHAIN (arg)) 9382 DECL_CONTEXT (arg) = fn; 9383 if (nested) 9384 DECL_INTERFACE_KNOWN (fn) = 1; 9385 9386 add_method (type, fn, NULL_TREE); 9387 9388 if (nested) 9389 push_function_context (); 9390 else 9391 /* Still increment function_depth so that we don't GC in the 9392 middle of an expression. */ 9393 ++function_depth; 9394 9395 /* Generate the body of the thunk. */ 9396 9397 start_preparsed_function (statfn, NULL_TREE, 9398 SF_PRE_PARSED | SF_INCLASS_INLINE); 9399 if (DECL_ONE_ONLY (statfn)) 9400 { 9401 /* Put the thunk in the same comdat group as the call op. */ 9402 cgraph_add_to_same_comdat_group (cgraph_get_create_node (statfn), 9403 cgraph_get_create_node (callop)); 9404 } 9405 body = begin_function_body (); 9406 compound_stmt = begin_compound_stmt (0); 9407 9408 arg = build1 (NOP_EXPR, TREE_TYPE (DECL_ARGUMENTS (callop)), 9409 null_pointer_node); 9410 argvec = make_tree_vector (); 9411 VEC_quick_push (tree, argvec, arg); 9412 for (arg = DECL_ARGUMENTS (statfn); arg; arg = DECL_CHAIN (arg)) 9413 { 9414 mark_exp_read (arg); 9415 VEC_safe_push (tree, gc, argvec, arg); 9416 } 9417 call = build_call_a (callop, VEC_length (tree, argvec), 9418 VEC_address (tree, argvec)); 9419 CALL_FROM_THUNK_P (call) = 1; 9420 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (call))) 9421 call = build_cplus_new (TREE_TYPE (call), call, tf_warning_or_error); 9422 call = convert_from_reference (call); 9423 finish_return_stmt (call); 9424 9425 finish_compound_stmt (compound_stmt); 9426 finish_function_body (body); 9427 9428 expand_or_defer_fn (finish_function (2)); 9429 9430 /* Generate the body of the conversion op. */ 9431 9432 start_preparsed_function (convfn, NULL_TREE, 9433 SF_PRE_PARSED | SF_INCLASS_INLINE); 9434 body = begin_function_body (); 9435 compound_stmt = begin_compound_stmt (0); 9436 9437 /* decl_needed_p needs to see that it's used. */ 9438 TREE_USED (statfn) = 1; 9439 finish_return_stmt (decay_conversion (statfn)); 9440 9441 finish_compound_stmt (compound_stmt); 9442 finish_function_body (body); 9443 9444 expand_or_defer_fn (finish_function (2)); 9445 9446 if (nested) 9447 pop_function_context (); 9448 else 9449 --function_depth; 9450 } 9451 9452 /* Returns true iff VAL is a lambda-related declaration which should 9453 be ignored by unqualified lookup. */ 9454 9455 bool 9456 is_lambda_ignored_entity (tree val) 9457 { 9458 /* In unevaluated context, look past normal capture proxies. */ 9459 if (cp_unevaluated_operand && is_normal_capture_proxy (val)) 9460 return true; 9461 9462 /* Always ignore lambda fields, their names are only for debugging. */ 9463 if (TREE_CODE (val) == FIELD_DECL 9464 && CLASSTYPE_LAMBDA_EXPR (DECL_CONTEXT (val))) 9465 return true; 9466 9467 /* None of the lookups that use qualify_lookup want the op() from the 9468 lambda; they want the one from the enclosing class. */ 9469 if (TREE_CODE (val) == FUNCTION_DECL && LAMBDA_FUNCTION_P (val)) 9470 return true; 9471 9472 return false; 9473 } 9474 9475 #include "gt-cp-semantics.h" 9476