1; Options for the language- and target-independent parts of the compiler. 2 3; Copyright (C) 2003-2018 Free Software Foundation, Inc. 4; 5; This file is part of GCC. 6; 7; GCC is free software; you can redistribute it and/or modify it under 8; the terms of the GNU General Public License as published by the Free 9; Software Foundation; either version 3, or (at your option) any later 10; version. 11; 12; GCC is distributed in the hope that it will be useful, but WITHOUT ANY 13; WARRANTY; without even the implied warranty of MERCHANTABILITY or 14; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15; for more details. 16; 17; You should have received a copy of the GNU General Public License 18; along with GCC; see the file COPYING3. If not see 19; <http://www.gnu.org/licenses/>. 20 21; See the GCC internals manual (options.texi) for a description of this file's format. 22 23; Please try to keep this file in ASCII collating order. 24 25Variable 26int target_flags 27 28Variable 29int optimize 30 31Variable 32int optimize_size 33 34Variable 35int optimize_debug 36 37; Not used directly to control optimizations, only to save -Ofast 38; setting for "optimize" attributes. 39Variable 40int optimize_fast 41 42; True if this is the lto front end. This is used to disable gimple 43; generation and lowering passes that are normally run on the output 44; of a front end. These passes must be bypassed for lto since they 45; have already been done before the gimple was written. 46Variable 47bool in_lto_p = false 48 49; This variable is set to non-0 only by LTO front-end. 1 indicates that 50; the output produced will be used for incrmeental linking (thus weak symbols 51; can still be bound). 52Variable 53int flag_incremental_link = 0 54 55; 0 means straightforward implementation of complex divide acceptable. 56; 1 means wide ranges of inputs must work for complex divide. 57; 2 means C99-like requirements for complex multiply and divide. 58Variable 59int flag_complex_method = 1 60 61; Language specific warning pass for unused results. 62Variable 63bool flag_warn_unused_result = false 64 65Variable 66int *param_values 67 68; Nonzero if we should write GIMPLE bytecode for link-time optimization. 69Variable 70int flag_generate_lto 71 72; Nonzero if we should write GIMPLE bytecode for offload compilation. 73Variable 74int flag_generate_offload = 0 75 76; True to warn about any objects definitions whose size is larger 77; than N bytes. Also want about function definitions whose returned 78; values are larger than N bytes, where N is 'larger_than_size'. 79Variable 80bool warn_larger_than 81 82Variable 83HOST_WIDE_INT larger_than_size 84 85; True to warn about any function whose frame size is larger 86; than N bytes. 87Variable 88bool warn_frame_larger_than 89 90Variable 91HOST_WIDE_INT frame_larger_than_size 92 93; Nonzero means we should be saving declaration info into a .X file. 94Variable 95int flag_gen_aux_info = 0 96 97; Nonzero if we are compiling code for a shared library, zero for 98; executable. 99Variable 100int flag_shlib 101 102; These two are really VEC(char_p,heap) *. 103 104Variable 105void *flag_instrument_functions_exclude_functions 106 107Variable 108void *flag_instrument_functions_exclude_files 109 110; Generic structs (e.g. templates not explicitly specialized) 111; may not have a compilation unit associated with them, and so 112; may need to be treated differently from ordinary structs. 113; 114; Structs only handled by reference (indirectly), will also usually 115; not need as much debugging information. 116 117Variable 118enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY } 119 120Variable 121enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY } 122 123; True if we should exit after parsing options. 124Variable 125bool exit_after_options 126 127; Type(s) of debugging information we are producing (if any). See 128; flag-types.h for the definitions of the different possible types of 129; debugging information. 130Variable 131enum debug_info_type write_symbols = NO_DEBUG 132 133; Level of debugging information we are producing. See flag-types.h 134; for the definitions of the different possible levels. 135Variable 136enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE 137 138; Nonzero means use GNU-only extensions in the generated symbolic 139; debugging information. Currently, this only has an effect when 140; write_symbols is set to DBX_DEBUG or XCOFF_DEBUG. 141Variable 142bool use_gnu_debug_info_extensions 143 144; Original value of maximum field alignment in bytes, specified via 145; -fpack-struct=<value>. 146Variable 147unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT 148 149; Type of stack check. 150Variable 151enum stack_check_type flag_stack_check = NO_STACK_CHECK 152 153; True if stack usage information needs to be computed. 154Variable 155bool flag_stack_usage_info = false 156 157; -dA causes debug commentary information to be produced in 158; the generated assembly code (to make it more readable). This option 159; is generally only of use to those who actually need to read the 160; generated assembly code (perhaps while debugging the compiler itself). 161; Currently, this switch is only used by dwarf2out.c; however, it is intended 162; to be a catchall for printing debug information in the assembler file. 163Variable 164int flag_debug_asm 165 166; How many NOP insns to place at each function entry by default 167Variable 168HOST_WIDE_INT function_entry_patch_area_size 169 170; And how far the real asm entry point is into this area 171Variable 172HOST_WIDE_INT function_entry_patch_area_start 173 174; Balance between GNAT encodings and standard DWARF to emit. 175Variable 176enum dwarf_gnat_encodings gnat_encodings = DWARF_GNAT_ENCODINGS_DEFAULT 177 178; -dP causes the rtl to be emitted as a comment in assembly. 179Variable 180int flag_dump_rtl_in_asm 181 182; Whether -da was passed (used only in handle_common_deferred_options). 183Variable 184bool flag_dump_all_passed 185 186; Other flags saying which kinds of debugging dump have been requested. 187 188Variable 189int rtl_dump_and_exit 190 191Variable 192int flag_print_asm_name 193 194; Name of top-level original source file (what was input to cpp). 195; This comes from the #-command at the beginning of the actual input. 196; If there isn't any there, then this is the cc1 input file name. 197Variable 198const char *main_input_filename 199 200; Pointer to base name in main_input_filename, with directories and a 201; single final extension removed, and the length of this base 202; name. 203 204Variable 205const char *main_input_basename 206 207Variable 208int main_input_baselength 209 210; Which options have been printed by --help. 211Variable 212char *help_printed 213 214; Which enums have been printed by --help. 0 = not printed, no 215; relevant options seen, 1 = relevant option seen, not yet printed, 2 216; = printed. 217Variable 218char *help_enum_printed 219 220; The number of columns for --help output. 221Variable 222unsigned int help_columns 223 224; Whether this options structure has been through finish_options 225Variable 226bool flag_opts_finished 227 228; What the sanitizer should instrument 229Variable 230unsigned int flag_sanitize 231 232; What sanitizers should recover from errors 233Variable 234unsigned int flag_sanitize_recover = (SANITIZE_UNDEFINED | SANITIZE_UNDEFINED_NONDEFAULT | SANITIZE_KERNEL_ADDRESS) & ~(SANITIZE_UNREACHABLE | SANITIZE_RETURN) 235 236; What the coverage sanitizers should instrument 237Variable 238unsigned int flag_sanitize_coverage 239 240; Flag whether a prefix has been added to dump_base_name 241Variable 242bool dump_base_name_prefixed = false 243 244; Flag whether HSA generation has been explicitely disabled 245Variable 246bool flag_disable_hsa = false 247 248### 249Driver 250 251-assemble 252Driver Alias(S) 253 254-compile 255Driver Alias(c) 256 257-coverage 258Driver Alias(coverage) 259 260-debug 261Common Alias(g) 262 263-dump 264Common Separate Alias(d) 265 266-dump= 267Common Joined Alias(d) 268 269-dumpbase 270Common Separate Alias(dumpbase) 271 272-dumpdir 273Common Separate Alias(dumpdir) 274 275-entry 276Driver Separate Alias(e) 277 278-entry= 279Driver Joined Alias(e) 280 281-extra-warnings 282Common Warning Alias(Wextra) 283 284-for-assembler 285Driver Separate Alias(Xassembler) 286 287-for-assembler= 288Driver JoinedOrMissing Alias(Xassembler) 289 290-for-linker 291Driver Separate Alias(Xlinker) 292 293-for-linker= 294Driver JoinedOrMissing Alias(Xlinker) 295 296-force-link 297Driver Separate Alias(u) 298 299-force-link= 300Driver Joined Alias(u) 301 302-help 303Common Driver Var(help_flag) 304Display this information. 305 306-help= 307Common Driver Report Joined 308--help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params. 309 310-language 311Driver Separate Alias(x) 312 313-language= 314Driver Joined Alias(x) 315 316-library-directory 317Driver Separate Alias(L) 318 319-library-directory= 320Driver Joined Alias(L) 321 322-no-canonical-prefixes 323Driver Alias(no-canonical-prefixes) 324 325-no-standard-libraries 326Driver Alias(nostdlib) 327 328-no-sysroot-suffix 329Driver Var(no_sysroot_suffix) 330 331-no-warnings 332Common Alias(w) 333 334-optimize 335Common Alias(O) 336 337-output 338Common Driver Separate Alias(o) MissingArgError(missing filename after %qs) 339 340-output= 341Common Driver Joined Alias(o) MissingArgError(missing filename after %qs) 342 343-pass-exit-codes 344Driver Alias(pass-exit-codes) 345 346-pedantic 347Common Alias(Wpedantic) 348 349-pedantic-errors 350Common Alias(pedantic-errors) 351 352-pie 353Driver Alias(pie) 354 355-static-pie 356Driver Alias(static-pie) 357 358-pipe 359Driver Alias(pipe) 360 361-prefix 362Driver Separate Alias(B) 363 364-prefix= 365Driver JoinedOrMissing Alias(B) 366 367-preprocess 368Driver Alias(E) 369 370-print-file-name 371Driver Separate Alias(print-file-name=) 372 373-print-file-name= 374Driver JoinedOrMissing Alias(print-file-name=) 375 376-print-libgcc-file-name 377Driver Alias(print-libgcc-file-name) 378 379-print-multi-directory 380Driver Alias(print-multi-directory) 381 382-print-multi-lib 383Driver Alias(print-multi-lib) 384 385-print-multi-os-directory 386Driver Alias(print-multi-os-directory) 387 388-print-multiarch 389Driver Alias(print-multiarch) 390 391-print-prog-name 392Driver Separate Alias(print-prog-name=) 393 394-print-prog-name= 395Driver JoinedOrMissing Alias(print-prog-name=) 396 397-print-search-dirs 398Driver Alias(print-search-dirs) 399 400-print-sysroot 401Driver Alias(print-sysroot) 402 403-print-sysroot-headers-suffix 404Driver Alias(print-sysroot-headers-suffix) 405 406-profile 407Common Alias(p) 408 409-save-temps 410Driver Alias(save-temps) 411 412-shared 413Driver Alias(shared) 414 415-specs 416Driver Separate Alias(specs=) 417 418-specs= 419Driver Joined Alias(specs=) 420 421-static 422Driver Alias(static) 423 424-symbolic 425Driver Alias(symbolic) 426 427-target-help 428Common Driver 429Alias for --help=target. 430 431-time 432Driver Alias(time) 433 434-verbose 435Driver Alias(v) 436 437;; The driver used to convert options such as --help into forms such 438;; as -fhelp; the following four entries are for compatibility with 439;; any direct uses of those (undocumented) -f forms 440fhelp 441Common Driver Alias(-help) 442 443fhelp= 444Common Driver Joined Alias(-help=) 445 446ftarget-help 447Common Driver Alias(-target-help) 448 449fversion 450Common Driver Alias(-version) 451 452-param 453Common Separate 454--param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters. 455 456-param= 457Common Joined Alias(-param) 458 459-sysroot 460Driver Separate Alias(-sysroot=) 461 462-sysroot= 463Driver JoinedOrMissing 464 465-version 466Common Driver 467 468B 469Driver Joined Separate 470 471E 472Driver 473 474L 475Driver Joined Separate 476 477N 478Driver 479 480O 481Common JoinedOrMissing Optimization 482-O<number> Set optimization level to <number>. 483 484Os 485Common Optimization 486Optimize for space rather than speed. 487 488Ofast 489Common Optimization 490Optimize for speed disregarding exact standards compliance. 491 492Og 493Common Optimization 494Optimize for debugging experience rather than speed or size. 495 496Q 497Driver 498 499Qn 500Driver Negative(Qy) 501 502Qy 503Driver Negative(Qn) 504 505R 506Driver Joined Separate 507 508S 509Driver 510 511T 512Driver Joined Separate 513 514Tbss 515Driver Separate 516 517Tbss= 518Driver Joined 519 520Tdata 521Driver Separate 522 523Tdata= 524Driver Joined 525 526Ttext 527Driver Separate 528 529Ttext= 530Driver Joined 531 532W 533Common RejectNegative Warning Alias(Wextra) 534This switch is deprecated; use -Wextra instead. 535 536Wa, 537Driver JoinedOrMissing RejectNegative 538 539Wl, 540Driver JoinedOrMissing RejectNegative 541 542Wp, 543Driver JoinedOrMissing RejectNegative 544 545Waggregate-return 546Common Var(warn_aggregate_return) Warning 547Warn about returning structures, unions or arrays. 548 549Waggressive-loop-optimizations 550Common Var(warn_aggressive_loop_optimizations) Init(1) Warning 551Warn if a loop with constant number of iterations triggers undefined behavior. 552 553Warray-bounds 554Common Var(warn_array_bounds) Warning 555Warn if an array is accessed out of bounds. 556 557Warray-bounds= 558Common Joined RejectNegative UInteger Var(warn_array_bounds) Warning IntegerRange(0, 2) 559Warn if an array is accessed out of bounds. 560 561Wattributes 562Common Var(warn_attributes) Init(1) Warning 563Warn about inappropriate attribute usage. 564 565Wattribute-alias 566Common Var(warn_attributes) Init(1) Warning 567Warn about type safety and similar errors in attribute alias and related. 568 569Wcast-align 570Common Var(warn_cast_align) Warning 571Warn about pointer casts which increase alignment. 572 573Wcast-align=strict 574Common Var(warn_cast_align,2) Warning 575Warn about pointer casts which increase alignment. 576 577Wcpp 578Common Var(warn_cpp) Init(1) Warning 579Warn when a #warning directive is encountered. 580 581Wdeprecated-declarations 582Common Var(warn_deprecated_decl) Init(1) Warning 583Warn about uses of __attribute__((deprecated)) declarations. 584 585Wdisabled-optimization 586Common Var(warn_disabled_optimization) Warning 587Warn when an optimization pass is disabled. 588 589Werror 590Common Var(warnings_are_errors) 591Treat all warnings as errors. 592 593Werror= 594Common Joined 595Treat specified warning as error. 596 597Wextra 598Common Var(extra_warnings) Warning 599Print extra (possibly unwanted) warnings. 600 601Wfatal-errors 602Common Var(flag_fatal_errors) 603Exit on the first error occurred. 604 605Wframe-larger-than= 606Common RejectNegative Joined UInteger Warning 607-Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes. 608 609Wfree-nonheap-object 610Common Var(warn_free_nonheap_object) Init(1) Warning 611Warn when attempting to free a non-heap object. 612 613Whsa 614Common Var(warn_hsa) Init(1) Warning 615Warn when a function cannot be expanded to HSAIL. 616 617Wimplicit-fallthrough 618Common Alias(Wimplicit-fallthrough=,3,0) Warning 619 620Wimplicit-fallthrough= 621Common Var(warn_implicit_fallthrough) RejectNegative Joined UInteger Warning IntegerRange(0, 5) 622Warn when a switch case falls through. 623 624Winline 625Common Var(warn_inline) Warning 626Warn when an inlined function cannot be inlined. 627 628Winvalid-memory-model 629Common Var(warn_invalid_memory_model) Init(1) Warning 630Warn when an atomic memory model parameter is known to be outside the valid range. 631 632Wlarger-than- 633Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=) 634 635Wlarger-than= 636Common RejectNegative Joined UInteger Warning 637-Wlarger-than=<number> Warn if an object is larger than <number> bytes. 638 639Wnonnull-compare 640Var(warn_nonnull_compare) Warning 641Warn if comparing pointer parameter with nonnull attribute with NULL. 642 643Wnull-dereference 644Common Var(warn_null_dereference) Warning 645Warn if dereferencing a NULL pointer may lead to erroneous or undefined behavior. 646 647Wunsafe-loop-optimizations 648Common Ignore Warning 649Does nothing. Preserved for backward compatibility. 650 651Wmissing-noreturn 652Common Warning Alias(Wsuggest-attribute=noreturn) 653 654Wodr 655Common Var(warn_odr_violations) Init(1) Warning 656Warn about some C++ One Definition Rule violations during link time optimization. 657 658Woverflow 659Common Var(warn_overflow) Init(1) Warning 660Warn about overflow in arithmetic expressions. 661 662Wlto-type-mismatch 663Common Var(warn_lto_type_mismatch) Init(1) Warning 664During link time optimization warn about mismatched types of global declarations. 665 666Wpacked 667Common Var(warn_packed) Warning 668Warn when the packed attribute has no effect on struct layout. 669 670Wpadded 671Common Var(warn_padded) Warning 672Warn when padding is required to align structure members. 673 674Wpedantic 675Common Var(pedantic) Init(0) Warning 676Issue warnings needed for strict compliance to the standard. 677 678Wreturn-local-addr 679Common Var(warn_return_local_addr) Init(1) Warning 680Warn about returning a pointer/reference to a local or temporary variable. 681 682Wshadow 683Common Var(warn_shadow) Warning 684Warn when one variable shadows another. Same as -Wshadow=global. 685 686Wshadow=global 687Common Warning Alias(Wshadow) 688Warn when one variable shadows another (globally). 689 690Wshadow=local 691Common Var(warn_shadow_local) Warning EnabledBy(Wshadow) 692Warn when one local variable shadows another local variable or parameter. 693 694Wshadow-local 695Common Warning Undocumented Alias(Wshadow=local) 696 697Wshadow=compatible-local 698Common Var(warn_shadow_compatible_local) Warning EnabledBy(Wshadow=local) 699Warn when one local variable shadows another local variable or parameter of compatible type. 700 701Wshadow-compatible-local 702Common Warning Undocumented Alias(Wshadow=compatible-local) 703 704Wstack-protector 705Common Var(warn_stack_protect) Warning 706Warn when not issuing stack smashing protection for some reason. 707 708Wstack-usage= 709Common Joined RejectNegative UInteger Var(warn_stack_usage) Warning 710-Wstack-usage=<number> Warn if stack usage might be larger than specified amount. 711 712Wstrict-aliasing 713Common Warning 714Warn about code which might break strict aliasing rules. 715 716Wstrict-aliasing= 717Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning 718Warn about code which might break strict aliasing rules. 719 720Wstrict-overflow 721Common Warning 722Warn about optimizations that assume that signed overflow is undefined. 723 724Wstrict-overflow= 725Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning 726Warn about optimizations that assume that signed overflow is undefined. 727 728Wsuggest-attribute=cold 729Common Var(warn_suggest_attribute_cold) Warning 730Warn about functions which might be candidates for __attribute__((cold)). 731 732Wsuggest-attribute=const 733Common Var(warn_suggest_attribute_const) Warning 734Warn about functions which might be candidates for __attribute__((const)). 735 736Wsuggest-attribute=pure 737Common Var(warn_suggest_attribute_pure) Warning 738Warn about functions which might be candidates for __attribute__((pure)). 739 740Wsuggest-attribute=noreturn 741Common Var(warn_suggest_attribute_noreturn) Warning 742Warn about functions which might be candidates for __attribute__((noreturn)). 743 744Wsuggest-attribute=malloc 745Common Var(warn_suggest_attribute_malloc) Warning 746Warn about functions which might be candidates for __attribute__((malloc)). 747 748Wsuggest-final-types 749Common Var(warn_suggest_final_types) Warning 750Warn about C++ polymorphic types where adding final keyword would improve code quality. 751 752Wsuggest-final-methods 753Common Var(warn_suggest_final_methods) Warning 754Warn about C++ virtual methods where adding final keyword would improve code quality. 755 756Wswitch-unreachable 757Common Var(warn_switch_unreachable) Warning Init(1) 758Warn about statements between switch's controlling expression and the first 759case. 760 761Wsystem-headers 762Common Var(warn_system_headers) Warning 763Do not suppress warnings from system headers. 764 765Wtrampolines 766Common Var(warn_trampolines) Warning 767Warn whenever a trampoline is generated. 768 769Wtype-limits 770Common Var(warn_type_limits) Warning EnabledBy(Wextra) 771Warn if a comparison is always true or always false due to the limited range of the data type. 772 773Wuninitialized 774Common Var(warn_uninitialized) Warning EnabledBy(Wextra) 775Warn about uninitialized automatic variables. 776 777Wmaybe-uninitialized 778Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized) 779Warn about maybe uninitialized automatic variables. 780 781Wunreachable-code 782Common Ignore Warning 783Does nothing. Preserved for backward compatibility. 784 785Wunused 786Common Var(warn_unused) Init(0) Warning 787Enable all -Wunused- warnings. 788 789Wunused-but-set-parameter 790Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra) 791Warn when a function parameter is only set, otherwise unused. 792 793Wunused-but-set-variable 794Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused) 795Warn when a variable is only set, otherwise unused. 796 797Wunused-function 798Common Var(warn_unused_function) Warning EnabledBy(Wunused) 799Warn when a function is unused. 800 801Wunused-label 802Common Var(warn_unused_label) Warning EnabledBy(Wunused) 803Warn when a label is unused. 804 805Wunused-parameter 806Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra) 807Warn when a function parameter is unused. 808 809Wunused-value 810Common Var(warn_unused_value) Warning EnabledBy(Wunused) 811Warn when an expression value is unused. 812 813Wunused-variable 814Common Var(warn_unused_variable) Warning EnabledBy(Wunused) 815Warn when a variable is unused. 816 817Wcoverage-mismatch 818Common Var(warn_coverage_mismatch) Init(1) Warning 819Warn in case profiles in -fprofile-use do not match. 820 821Wvector-operation-performance 822Common Var(warn_vector_operation_performance) Warning 823Warn when a vector operation is compiled outside the SIMD. 824 825Xassembler 826Driver Separate 827 828Xlinker 829Driver Separate 830 831Xpreprocessor 832Driver Separate 833 834Z 835Driver 836 837aux-info 838Common Separate Var(aux_info_file_name) 839-aux-info <file> Emit declaration information into <file>. 840 841aux-info= 842Common Joined Alias(aux-info) 843 844auxbase 845Common Separate RejectDriver Var(aux_base_name) 846 847auxbase-strip 848Common Separate RejectDriver 849 850coverage 851Driver 852 853c 854Driver 855 856d 857Common Joined 858-d<letters> Enable dumps from specific passes of the compiler. 859 860dumpbase 861Common Separate Var(dump_base_name) 862-dumpbase <file> Set the file basename to be used for dumps. 863 864dumpdir 865Common Separate Var(dump_dir_name) 866-dumpdir <dir> Set the directory name to be used for dumps. 867 868dumpmachine 869Driver 870 871dumpspecs 872Driver 873 874dumpversion 875Driver 876 877dumpfullversion 878Driver 879 880e 881Driver Joined Separate 882 883; This option has historically been passed down to the linker by an 884; accident of a %{e*} spec, so ensure it continues to be passed down 885; as a single option. The supported option for this purpose is 886; -rdynamic. See PR 47390. 887export-dynamic 888Driver Undocumented 889 890; The version of the C++ ABI in use. The following values are allowed: 891; 892; 0: The version of the ABI believed most conformant with the C++ ABI 893; specification. This ABI may change as bugs are discovered and fixed. 894; Therefore, 0 will not necessarily indicate the same ABI in different 895; versions of G++. 896; 897; 1: The version of the ABI first used in G++ 3.2. No longer selectable. 898; 899; 2: The version of the ABI first used in G++ 3.4, and the default 900; until GCC 4.9. 901; 902; 3: The version of the ABI that fixes the missing underscore 903; in template non-type arguments of pointer type. 904; 905; 4: The version of the ABI that introduces unambiguous mangling of 906; vector types. First selectable in G++ 4.5. 907; 908; 5: The version of the ABI that ignores attribute const/noreturn 909; in function pointer mangling, and corrects mangling of decltype and 910; function parameters used in other parameters and the return type. 911; First selectable in G++ 4.6. 912; 913; 6: The version of the ABI that doesn't promote scoped enums to int and 914; changes the mangling of template argument packs, const/static_cast, 915; prefix ++ and --, and a class scope function used as a template 916; argument. 917; First selectable in G++ 4.7. 918; 919; 7: The version of the ABI that treats nullptr_t as a builtin type and 920; corrects the mangling of lambdas in default argument scope. 921; First selectable in G++ 4.8. 922; 923; 8: The version of the ABI that corrects the substitution behavior of 924; function types with function-cv-qualifiers. 925; First selectable in G++ 4.9 and default in G++ 5. 926; 927; 9: The version of the ABI that corrects the alignment of nullptr_t. 928; First selectable and default in G++ 5.2. 929; 930; 10: The version of the ABI that mangles attributes that affect type 931; identity, such as ia32 calling convention attributes (stdcall, etc.) 932; Default in G++ 6 (set in c_common_post_options). 933; 934; 11: The version of the ABI that corrects mangling of sizeof... expressions 935; and introduces new inheriting constructor handling. 936; Default in G++ 7. 937; 938; 12: Corrects the calling convention for classes with only deleted copy/move 939; constructors and changes passing/returning of empty records. 940; Default in G++ 8.1. 941; 942; 13: Fixes the accidental change in 12 to the calling convention for classes 943; with deleted copy constructor and trivial move constructor. 944; Default in G++ 8.2. 945; 946; Additional positive integers will be assigned as new versions of 947; the ABI become the default version of the ABI. 948fabi-version= 949Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0) 950The version of the C++ ABI in use. 951 952faggressive-loop-optimizations 953Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1) 954Aggressively optimize loops using language constraints. 955 956falign-functions 957Common Report Var(align_functions,0) Optimization UInteger 958Align the start of functions. 959 960falign-functions= 961Common RejectNegative Joined UInteger Var(align_functions) Optimization 962 963flimit-function-alignment 964Common Report Var(flag_limit_function_alignment) Optimization Init(0) 965 966falign-jumps 967Common Report Var(align_jumps,0) Optimization UInteger 968Align labels which are only reached by jumping. 969 970falign-jumps= 971Common RejectNegative Joined UInteger Var(align_jumps) Optimization 972 973falign-labels 974Common Report Var(align_labels,0) Optimization UInteger 975Align all labels. 976 977falign-labels= 978Common RejectNegative Joined UInteger Var(align_labels) Optimization 979 980falign-loops 981Common Report Var(align_loops,0) Optimization UInteger 982Align the start of loops. 983 984falign-loops= 985Common RejectNegative Joined UInteger Var(align_loops) Optimization 986 987fargument-alias 988Common Ignore 989Does nothing. Preserved for backward compatibility. 990 991fargument-noalias 992Common Ignore 993Does nothing. Preserved for backward compatibility. 994 995fargument-noalias-global 996Common Ignore 997Does nothing. Preserved for backward compatibility. 998 999fargument-noalias-anything 1000Common Ignore 1001Does nothing. Preserved for backward compatibility. 1002 1003fsanitize= 1004Common Driver Report Joined 1005Select what to sanitize. 1006 1007fsanitize-coverage= 1008Common Report Joined 1009Select type of coverage sanitization. 1010 1011fasan-shadow-offset= 1012Common Joined RejectNegative Var(common_deferred_options) Defer 1013-fasan-shadow-offset=<number> Use custom shadow memory offset. 1014 1015fsanitize-sections= 1016Common Joined RejectNegative Var(common_deferred_options) Defer 1017-fsanitize-sections=<sec1,sec2,...> Sanitize global variables 1018in user-defined sections. 1019 1020fsanitize-recover= 1021Common Report Joined 1022After diagnosing undefined behavior attempt to continue execution. 1023 1024fsanitize-recover 1025Common Report 1026This switch is deprecated; use -fsanitize-recover= instead. 1027 1028fsanitize-address-use-after-scope 1029Common Driver Report Var(flag_sanitize_address_use_after_scope) Init(0) 1030 1031fsanitize-undefined-trap-on-error 1032Common Driver Report Var(flag_sanitize_undefined_trap_on_error) Init(0) 1033Use trap instead of a library function for undefined behavior sanitization. 1034 1035fasynchronous-unwind-tables 1036Common Report Var(flag_asynchronous_unwind_tables) Optimization 1037Generate unwind tables that are exact at each instruction boundary. 1038 1039fauto-inc-dec 1040Common Report Var(flag_auto_inc_dec) Init(1) Optimization 1041Generate auto-inc/dec instructions. 1042 1043fauto-profile 1044Common Report Var(flag_auto_profile) 1045Use sample profile information for call graph node weights. The default 1046profile file is fbdata.afdo in 'pwd'. 1047 1048fauto-profile= 1049Common Joined RejectNegative Var(auto_profile_file) 1050Use sample profile information for call graph node weights. The profile 1051file is specified in the argument. 1052 1053; -fcheck-bounds causes gcc to generate array bounds checks. 1054; For C, C++ and ObjC: defaults off. 1055; For Java: defaults to on. 1056; For Fortran: defaults to off. 1057fbounds-check 1058Common Report Var(flag_bounds_check) 1059Generate code to check bounds before indexing arrays. 1060 1061fbranch-count-reg 1062Common Report Var(flag_branch_on_count_reg) Optimization 1063Replace add, compare, branch with branch on count register. 1064 1065fbranch-probabilities 1066Common Report Var(flag_branch_probabilities) Optimization 1067Use profiling information for branch probabilities. 1068 1069fbranch-target-load-optimize 1070Common Report Var(flag_branch_target_load_optimize) Optimization 1071Perform branch target load optimization before prologue / epilogue threading. 1072 1073fbranch-target-load-optimize2 1074Common Report Var(flag_branch_target_load_optimize2) Optimization 1075Perform branch target load optimization after prologue / epilogue threading. 1076 1077fbtr-bb-exclusive 1078Common Report Var(flag_btr_bb_exclusive) Optimization 1079Restrict target load migration not to re-use registers in any basic block. 1080 1081fcall-saved- 1082Common Joined RejectNegative Var(common_deferred_options) Defer 1083-fcall-saved-<register> Mark <register> as being preserved across functions. 1084 1085fcall-used- 1086Common Joined RejectNegative Var(common_deferred_options) Defer 1087-fcall-used-<register> Mark <register> as being corrupted by function calls. 1088 1089; Nonzero for -fcaller-saves: allocate values in regs that need to 1090; be saved across function calls, if that produces overall better code. 1091; Optional now, so people can test it. 1092fcaller-saves 1093Common Report Var(flag_caller_saves) Optimization 1094Save registers around function calls. 1095 1096fcheck-data-deps 1097Common Report Var(flag_check_data_deps) 1098This switch is deprecated; do not use. 1099 1100fcheck-new 1101Common Var(flag_check_new) 1102Check the return value of new in C++. 1103 1104fchecking 1105Common Var(flag_checking) Init(CHECKING_P ? ENABLE_EXTRA_CHECKING ? 2 : 1 : 0) 1106Perform internal consistency checkings. 1107 1108fchecking= 1109Common Joined RejectNegative UInteger Var(flag_checking) 1110Perform internal consistency checkings. 1111 1112fcode-hoisting 1113Common Report Var(flag_code_hoisting) Optimization 1114Enable code hoisting. 1115 1116fcombine-stack-adjustments 1117Common Report Var(flag_combine_stack_adjustments) Optimization 1118Looks for opportunities to reduce stack adjustments and stack references. 1119 1120fcommon 1121Common Report Var(flag_no_common,0) 1122Do not put uninitialized globals in the common section. 1123 1124fcompare-debug 1125Driver 1126; Converted by the driver to -fcompare-debug= options. 1127 1128fcompare-debug= 1129Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt) 1130-fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump. 1131 1132fcompare-debug-second 1133Common Driver RejectNegative Var(flag_compare_debug) 1134Run only the second compilation of -fcompare-debug. 1135 1136fcompare-elim 1137Common Report Var(flag_compare_elim_after_reload) Optimization 1138Perform comparison elimination after register allocation has finished. 1139 1140fconserve-stack 1141Common Var(flag_conserve_stack) Optimization 1142Do not perform optimizations increasing noticeably stack usage. 1143 1144fcprop-registers 1145Common Report Var(flag_cprop_registers) Optimization 1146Perform a register copy-propagation optimization pass. 1147 1148fcrossjumping 1149Common Report Var(flag_crossjumping) Optimization 1150Perform cross-jumping optimization. 1151 1152fcse-follow-jumps 1153Common Report Var(flag_cse_follow_jumps) Optimization 1154When running CSE, follow jumps to their targets. 1155 1156fcse-skip-blocks 1157Common Ignore 1158Does nothing. Preserved for backward compatibility. 1159 1160fcx-limited-range 1161Common Report Var(flag_cx_limited_range) Optimization SetByCombined 1162Omit range reduction step when performing complex division. 1163 1164fcx-fortran-rules 1165Common Report Var(flag_cx_fortran_rules) Optimization 1166Complex multiplication and division follow Fortran rules. 1167 1168fdata-sections 1169Common Report Var(flag_data_sections) 1170Place data items into their own section. 1171 1172fdbg-cnt-list 1173Common Report Var(common_deferred_options) Defer 1174List all available debugging counters with their limits and counts. 1175 1176fdbg-cnt= 1177Common RejectNegative Joined Var(common_deferred_options) Defer 1178-fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit. 1179 1180fdebug-prefix-map= 1181Common Joined RejectNegative Var(common_deferred_options) Defer 1182-fdebug-prefix-map=<old>=<new> Map one directory name to another in debug information. 1183 1184ffile-prefix-map= 1185Common Joined RejectNegative Var(common_deferred_options) Defer 1186-ffile-prefix-map=<old>=<new> Map one directory name to another in compilation result. 1187 1188fdebug-types-section 1189Common Report Var(flag_debug_types_section) Init(0) 1190Output .debug_types section when using DWARF v4 debuginfo. 1191 1192; Nonzero for -fdefer-pop: don't pop args after each function call 1193; instead save them up to pop many calls' args with one insns. 1194fdefer-pop 1195Common Report Var(flag_defer_pop) Optimization 1196Defer popping functions args from stack until later. 1197 1198fdelayed-branch 1199Common Report Var(flag_delayed_branch) Optimization 1200Attempt to fill delay slots of branch instructions. 1201 1202fdelete-dead-exceptions 1203Common Report Var(flag_delete_dead_exceptions) Init(0) Optimization 1204Delete dead instructions that may throw exceptions. 1205 1206fdelete-null-pointer-checks 1207Common Report Var(flag_delete_null_pointer_checks) Init(-1) Optimization 1208Delete useless null pointer checks. 1209 1210fdevirtualize-at-ltrans 1211Common Report Var(flag_ltrans_devirtualize) 1212Stream extra data to support more aggressive devirtualization in LTO local transformation mode. 1213 1214fdevirtualize-speculatively 1215Common Report Var(flag_devirtualize_speculatively) Optimization 1216Perform speculative devirtualization. 1217 1218fdevirtualize 1219Common Report Var(flag_devirtualize) Optimization 1220Try to convert virtual calls to direct ones. 1221 1222fdiagnostics-show-location= 1223Common Joined RejectNegative Enum(diagnostic_prefixing_rule) 1224-fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics. 1225 1226; Required for these enum values. 1227SourceInclude 1228pretty-print.h 1229 1230Enum 1231Name(diagnostic_prefixing_rule) Type(int) 1232 1233EnumValue 1234Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE) 1235 1236EnumValue 1237Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE) 1238 1239fdiagnostics-show-caret 1240Common Var(flag_diagnostics_show_caret) Init(1) 1241Show the source line with a caret indicating the column. 1242 1243fdiagnostics-color 1244Common Alias(fdiagnostics-color=,always,never) 1245; 1246 1247fdiagnostics-color= 1248Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO) 1249-fdiagnostics-color=[never|always|auto] Colorize diagnostics. 1250 1251; Required for these enum values. 1252SourceInclude 1253diagnostic-color.h 1254 1255Enum 1256Name(diagnostic_color_rule) Type(int) 1257 1258EnumValue 1259Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO) 1260 1261EnumValue 1262Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES) 1263 1264EnumValue 1265Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO) 1266 1267fdiagnostics-parseable-fixits 1268Common Var(flag_diagnostics_parseable_fixits) 1269Print fix-it hints in machine-readable form. 1270 1271fdiagnostics-generate-patch 1272Common Var(flag_diagnostics_generate_patch) 1273Print fix-it hints to stderr in unified diff format. 1274 1275fdiagnostics-show-option 1276Common Var(flag_diagnostics_show_option) Init(1) 1277Amend appropriate diagnostic messages with the command line option that controls them. 1278 1279fdisable- 1280Common Joined RejectNegative Var(common_deferred_options) Defer 1281-fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass. 1282 1283fenable- 1284Common Joined RejectNegative Var(common_deferred_options) Defer 1285-fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass. 1286 1287fdump- 1288Common Joined RejectNegative Var(common_deferred_options) Defer 1289-fdump-<type> Dump various compiler internals to a file. 1290 1291fdump-final-insns 1292Driver RejectNegative 1293 1294fdump-final-insns= 1295Common RejectNegative Joined Var(flag_dump_final_insns) 1296-fdump-final-insns=filename Dump to filename the insns at the end of translation. 1297 1298fdump-go-spec= 1299Common RejectNegative Joined Var(flag_dump_go_spec) 1300-fdump-go-spec=filename Write all declarations to file as Go code. 1301 1302fdump-noaddr 1303Common Report Var(flag_dump_noaddr) 1304Suppress output of addresses in debugging dumps. 1305 1306freport-bug 1307Common Driver Var(flag_report_bug) 1308Collect and dump debug information into temporary file if ICE in C/C++ 1309compiler occurred. 1310 1311fdump-internal-locations 1312Common Var(flag_dump_locations) Init(0) 1313Dump detailed information on GCC's internal representation of source code locations. 1314 1315fdump-passes 1316Common Var(flag_dump_passes) Init(0) 1317Dump optimization passes. 1318 1319fdump-unnumbered 1320Common Report Var(flag_dump_unnumbered) 1321Suppress output of instruction numbers, line number notes and addresses in debugging dumps. 1322 1323fdump-unnumbered-links 1324Common Report Var(flag_dump_unnumbered_links) 1325Suppress output of previous and next insn numbers in debugging dumps. 1326 1327fdwarf2-cfi-asm 1328Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE) 1329Enable CFI tables via GAS assembler directives. 1330 1331fearly-inlining 1332Common Report Var(flag_early_inlining) Init(1) Optimization 1333Perform early inlining. 1334 1335feliminate-dwarf2-dups 1336Common Ignore 1337Does nothing. Preserved for backward compatibility. 1338 1339fipa-sra 1340Common Report Var(flag_ipa_sra) Init(0) Optimization 1341Perform interprocedural reduction of aggregates. 1342 1343feliminate-unused-debug-symbols 1344Common Report Var(flag_debug_only_used_symbols) 1345Perform unused symbol elimination in debug info. 1346 1347feliminate-unused-debug-types 1348Common Report Var(flag_eliminate_unused_debug_types) Init(1) 1349Perform unused type elimination in debug info. 1350 1351femit-class-debug-always 1352Common Report Var(flag_emit_class_debug_always) Init(0) 1353Do not suppress C++ class debug information. 1354 1355fexceptions 1356Common Report Var(flag_exceptions) Optimization 1357Enable exception handling. 1358 1359fexpensive-optimizations 1360Common Report Var(flag_expensive_optimizations) Optimization 1361Perform a number of minor, expensive optimizations. 1362 1363fexcess-precision= 1364Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT) SetByCombined 1365-fexcess-precision=[fast|standard] Specify handling of excess floating-point precision. 1366 1367Enum 1368Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs) 1369 1370EnumValue 1371Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST) 1372 1373EnumValue 1374Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD) 1375 1376; Whether we permit the extended set of values for FLT_EVAL_METHOD 1377; introduced in ISO/IEC TS 18661-3, or limit ourselves to those in C99/C11. 1378fpermitted-flt-eval-methods= 1379Common Joined RejectNegative Enum(permitted_flt_eval_methods) Var(flag_permitted_flt_eval_methods) Init(PERMITTED_FLT_EVAL_METHODS_DEFAULT) 1380-fpermitted-flt-eval-methods=[c11|ts-18661] Specify which values of FLT_EVAL_METHOD are permitted. 1381 1382Enum 1383Name(permitted_flt_eval_methods) Type(enum permitted_flt_eval_methods) UnknownError(unknown specification for the set of FLT_EVAL_METHOD values to permit %qs) 1384 1385EnumValue 1386Enum(permitted_flt_eval_methods) String(c11) Value(PERMITTED_FLT_EVAL_METHODS_C11) 1387 1388EnumValue 1389Enum(permitted_flt_eval_methods) String(ts-18661-3) Value(PERMITTED_FLT_EVAL_METHODS_TS_18661) 1390 1391ffast-math 1392Common Optimization 1393 1394ffat-lto-objects 1395Common Var(flag_fat_lto_objects) 1396Output lto objects containing both the intermediate language and binary output. 1397 1398ffinite-math-only 1399Common Report Var(flag_finite_math_only) Optimization SetByCombined 1400Assume no NaNs or infinities are generated. 1401 1402ffixed- 1403Common Joined RejectNegative Var(common_deferred_options) Defer 1404-ffixed-<register> Mark <register> as being unavailable to the compiler. 1405 1406ffloat-store 1407Common Report Var(flag_float_store) Optimization 1408Don't allocate floats and doubles in extended-precision registers. 1409 1410fforce-addr 1411Common Ignore 1412Does nothing. Preserved for backward compatibility. 1413 1414fforward-propagate 1415Common Report Var(flag_forward_propagate) Optimization 1416Perform a forward propagation pass on RTL. 1417 1418ffp-contract= 1419Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization 1420-ffp-contract=[off|on|fast] Perform floating-point expression contraction. 1421 1422Enum 1423Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs) 1424 1425EnumValue 1426Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF) 1427 1428; Not implemented, fall back to conservative FP_CONTRACT_OFF. 1429EnumValue 1430Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF) 1431 1432EnumValue 1433Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST) 1434 1435ffp-int-builtin-inexact 1436Common Report Var(flag_fp_int_builtin_inexact) Init(1) Optimization 1437Allow built-in functions ceil, floor, round, trunc to raise \"inexact\" exceptions. 1438 1439; Nonzero means don't put addresses of constant functions in registers. 1440; Used for compiling the Unix kernel, where strange substitutions are 1441; done on the assembly output. 1442ffunction-cse 1443Common Report Var(flag_no_function_cse,0) Optimization 1444Allow function addresses to be held in registers. 1445 1446ffunction-sections 1447Common Report Var(flag_function_sections) 1448Place each function into its own section. 1449 1450fgcse 1451Common Report Var(flag_gcse) Optimization 1452Perform global common subexpression elimination. 1453 1454fgcse-lm 1455Common Report Var(flag_gcse_lm) Init(1) Optimization 1456Perform enhanced load motion during global common subexpression elimination. 1457 1458fgcse-sm 1459Common Report Var(flag_gcse_sm) Init(0) Optimization 1460Perform store motion after global common subexpression elimination. 1461 1462fgcse-las 1463Common Report Var(flag_gcse_las) Init(0) Optimization 1464Perform redundant load after store elimination in global common subexpression 1465elimination. 1466 1467fgcse-after-reload 1468Common Report Var(flag_gcse_after_reload) Optimization 1469Perform global common subexpression elimination after register allocation has 1470finished. 1471 1472Enum 1473Name(dwarf_gnat_encodings) Type(int) 1474 1475EnumValue 1476Enum(dwarf_gnat_encodings) String(all) Value(DWARF_GNAT_ENCODINGS_ALL) 1477 1478EnumValue 1479Enum(dwarf_gnat_encodings) String(gdb) Value(DWARF_GNAT_ENCODINGS_GDB) 1480 1481EnumValue 1482Enum(dwarf_gnat_encodings) String(minimal) Value(DWARF_GNAT_ENCODINGS_MINIMAL) 1483 1484fgnat-encodings= 1485Common Enum(dwarf_gnat_encodings) Joined RejectNegative Report Undocumented Var(gnat_encodings) 1486-fgnat-encodings=[all|gdb|minimal] Select the balance between GNAT encodings and standard DWARF emitted in the debug information 1487 1488; This option is not documented yet as its semantics will change. 1489fgraphite 1490Common Report Var(flag_graphite) Optimization 1491Enable in and out of Graphite representation. 1492 1493fgraphite-identity 1494Common Report Var(flag_graphite_identity) Optimization 1495Enable Graphite Identity transformation. 1496 1497fhoist-adjacent-loads 1498Common Report Var(flag_hoist_adjacent_loads) Optimization 1499Enable hoisting adjacent loads to encourage generating conditional move 1500instructions. 1501 1502fkeep-gc-roots-live 1503Common Undocumented Report Var(flag_keep_gc_roots_live) Optimization 1504; Always keep a pointer to a live memory block 1505 1506floop-parallelize-all 1507Common Report Var(flag_loop_parallelize_all) Optimization 1508Mark all loops as parallel. 1509 1510floop-strip-mine 1511Common Alias(floop-nest-optimize) 1512Enable loop nest transforms. Same as -floop-nest-optimize. 1513 1514floop-interchange 1515Common Report Var(flag_loop_interchange) Optimization 1516Enable loop interchange on trees. 1517 1518floop-block 1519Common Alias(floop-nest-optimize) 1520Enable loop nest transforms. Same as -floop-nest-optimize. 1521 1522floop-unroll-and-jam 1523Common Report Var(flag_unroll_jam) Optimization 1524Perform unroll-and-jam on loops. 1525 1526fgnu-tm 1527Common Report Var(flag_tm) 1528Enable support for GNU transactional memory. 1529 1530fgnu-unique 1531Common Report Var(flag_gnu_unique) Init(1) 1532Use STB_GNU_UNIQUE if supported by the assembler. 1533 1534floop-flatten 1535Common Ignore 1536Does nothing. Preserved for backward compatibility. 1537 1538floop-nest-optimize 1539Common Report Var(flag_loop_nest_optimize) Optimization 1540Enable the loop nest optimizer. 1541 1542fstrict-volatile-bitfields 1543Common Report Var(flag_strict_volatile_bitfields) Init(-1) Optimization 1544Force bitfield accesses to match their type width. 1545 1546fstore-merging 1547Common Report Var(flag_store_merging) Optimization 1548Merge adjacent stores. 1549 1550fguess-branch-probability 1551Common Report Var(flag_guess_branch_prob) Optimization 1552Enable guessing of branch probabilities. 1553 1554; Nonzero means ignore `#ident' directives. 0 means handle them. 1555; Generate position-independent code for executables if possible 1556; On SVR4 targets, it also controls whether or not to emit a 1557; string identifying the compiler. 1558fident 1559Common Report Var(flag_no_ident,0) 1560Process #ident directives. 1561 1562fif-conversion 1563Common Report Var(flag_if_conversion) Optimization 1564Perform conversion of conditional jumps to branchless equivalents. 1565 1566fif-conversion2 1567Common Report Var(flag_if_conversion2) Optimization 1568Perform conversion of conditional jumps to conditional execution. 1569 1570fstack-reuse= 1571Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization 1572-fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables. 1573 1574Enum 1575Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs) 1576 1577EnumValue 1578Enum(stack_reuse_level) String(all) Value(SR_ALL) 1579 1580EnumValue 1581Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS) 1582 1583EnumValue 1584Enum(stack_reuse_level) String(none) Value(SR_NONE) 1585 1586ftree-loop-if-convert 1587Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization 1588Convert conditional jumps in innermost loops to branchless equivalents. 1589 1590ftree-loop-if-convert-stores 1591Common Ignore 1592Does nothing. Preserved for backward compatibility. 1593 1594; -finhibit-size-directive inhibits output of .size for ELF. 1595; This is used only for compiling crtstuff.c, 1596; and it may be extended to other effects 1597; needed for crtstuff.c on other systems. 1598finhibit-size-directive 1599Common Report Var(flag_inhibit_size_directive) 1600Do not generate .size directives. 1601 1602findirect-inlining 1603Common Report Var(flag_indirect_inlining) Optimization 1604Perform indirect inlining. 1605 1606; General flag to enable inlining. Specifying -fno-inline will disable 1607; all inlining apart from always-inline functions. 1608finline 1609Common Report Var(flag_no_inline,0) Init(0) Optimization 1610Enable inlining of function declared \"inline\", disabling disables all inlining. 1611 1612finline-small-functions 1613Common Report Var(flag_inline_small_functions) Optimization 1614Integrate functions into their callers when code size is known not to grow. 1615 1616finline-functions 1617Common Report Var(flag_inline_functions) Optimization 1618Integrate functions not declared \"inline\" into their callers when profitable. 1619 1620finline-functions-called-once 1621Common Report Var(flag_inline_functions_called_once) Optimization 1622Integrate functions only required by their single caller. 1623 1624finline-limit- 1625Common RejectNegative Joined Alias(finline-limit=) 1626 1627finline-limit= 1628Common RejectNegative Joined UInteger 1629-finline-limit=<number> Limit the size of inlined functions to <number>. 1630 1631finline-atomics 1632Common Report Var(flag_inline_atomics) Init(1) Optimization 1633Inline __atomic operations when a lock free instruction sequence is available. 1634 1635fcf-protection 1636Common RejectNegative Alias(fcf-protection=,full) 1637 1638fcf-protection= 1639Common Report Joined RejectNegative Enum(cf_protection_level) Var(flag_cf_protection) Init(CF_NONE) 1640-fcf-protection=[full|branch|return|none] Instrument functions with checks to verify jump/call/return control-flow transfer 1641instructions have valid targets. 1642 1643Enum 1644Name(cf_protection_level) Type(enum cf_protection_level) UnknownError(unknown Control-Flow Protection Level %qs) 1645 1646EnumValue 1647Enum(cf_protection_level) String(full) Value(CF_FULL) 1648 1649EnumValue 1650Enum(cf_protection_level) String(branch) Value(CF_BRANCH) 1651 1652EnumValue 1653Enum(cf_protection_level) String(return) Value(CF_RETURN) 1654 1655EnumValue 1656Enum(cf_protection_level) String(none) Value(CF_NONE) 1657 1658finstrument-functions 1659Common Report Var(flag_instrument_function_entry_exit) 1660Instrument function entry and exit with profiling calls. 1661 1662finstrument-functions-exclude-function-list= 1663Common RejectNegative Joined 1664-finstrument-functions-exclude-function-list=name,... Do not instrument listed functions. 1665 1666finstrument-functions-exclude-file-list= 1667Common RejectNegative Joined 1668-finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files. 1669 1670fipa-cp 1671Common Report Var(flag_ipa_cp) Optimization 1672Perform interprocedural constant propagation. 1673 1674fipa-cp-clone 1675Common Report Var(flag_ipa_cp_clone) Optimization 1676Perform cloning to make Interprocedural constant propagation stronger. 1677 1678fipa-cp-alignment 1679Common Ignore 1680Does nothing. Preserved for backward compatibility. 1681 1682fipa-bit-cp 1683Common Report Var(flag_ipa_bit_cp) Optimization 1684Perform interprocedural bitwise constant propagation. 1685 1686fipa-profile 1687Common Report Var(flag_ipa_profile) Init(0) Optimization 1688Perform interprocedural profile propagation. 1689 1690fipa-pta 1691Common Report Var(flag_ipa_pta) Init(0) Optimization 1692Perform interprocedural points-to analysis. 1693 1694fipa-pure-const 1695Common Report Var(flag_ipa_pure_const) Init(0) Optimization 1696Discover pure and const functions. 1697 1698fipa-icf 1699Common Report Var(flag_ipa_icf) Optimization 1700Perform Identical Code Folding for functions and read-only variables. 1701 1702fipa-icf-functions 1703Common Report Var(flag_ipa_icf_functions) Optimization 1704Perform Identical Code Folding for functions. 1705 1706fipa-icf-variables 1707Common Report Var(flag_ipa_icf_variables) Optimization 1708Perform Identical Code Folding for variables. 1709 1710fipa-reference 1711Common Report Var(flag_ipa_reference) Init(0) Optimization 1712Discover readonly and non addressable static variables. 1713 1714fipa-matrix-reorg 1715Common Ignore 1716Does nothing. Preserved for backward compatibility. 1717 1718fipa-struct-reorg 1719Common Ignore 1720Does nothing. Preserved for backward compatibility. 1721 1722fipa-vrp 1723Common Report Var(flag_ipa_vrp) Optimization 1724Perform IPA Value Range Propagation. 1725 1726fira-algorithm= 1727Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization 1728-fira-algorithm=[CB|priority] Set the used IRA algorithm. 1729 1730Enum 1731Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs) 1732 1733EnumValue 1734Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB) 1735 1736EnumValue 1737Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY) 1738 1739fira-region= 1740Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT) Optimization 1741-fira-region=[one|all|mixed] Set regions for IRA. 1742 1743Enum 1744Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs) 1745 1746EnumValue 1747Enum(ira_region) String(one) Value(IRA_REGION_ONE) 1748 1749EnumValue 1750Enum(ira_region) String(all) Value(IRA_REGION_ALL) 1751 1752EnumValue 1753Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED) 1754 1755fira-hoist-pressure 1756Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization 1757Use IRA based register pressure calculation 1758in RTL hoist optimizations. 1759 1760fira-loop-pressure 1761Common Report Var(flag_ira_loop_pressure) Optimization 1762Use IRA based register pressure calculation 1763in RTL loop optimizations. 1764 1765fira-share-save-slots 1766Common Report Var(flag_ira_share_save_slots) Init(1) Optimization 1767Share slots for saving different hard registers. 1768 1769fira-share-spill-slots 1770Common Report Var(flag_ira_share_spill_slots) Init(1) Optimization 1771Share stack slots for spilled pseudo-registers. 1772 1773fira-verbose= 1774Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5) 1775-fira-verbose=<number> Control IRA's level of diagnostic messages. 1776 1777fivopts 1778Common Report Var(flag_ivopts) Init(1) Optimization 1779Optimize induction variables on trees. 1780 1781fjump-tables 1782Common Var(flag_jump_tables) Init(1) Optimization 1783Use jump tables for sufficiently large switch statements. 1784 1785fkeep-inline-functions 1786Common Report Var(flag_keep_inline_functions) 1787Generate code for functions even if they are fully inlined. 1788 1789fkeep-static-functions 1790Common Report Var(flag_keep_static_functions) 1791Generate code for static functions even if they are never called. 1792 1793fkeep-static-consts 1794Common Report Var(flag_keep_static_consts) Init(1) 1795Emit static const variables even if they are not used. 1796 1797fleading-underscore 1798Common Report Var(flag_leading_underscore) Init(-1) 1799Give external symbols a leading underscore. 1800 1801floop-optimize 1802Common Ignore 1803Does nothing. Preserved for backward compatibility. 1804 1805flra-remat 1806Common Report Var(flag_lra_remat) Optimization 1807Do CFG-sensitive rematerialization in LRA. 1808 1809flto 1810Common 1811Enable link-time optimization. 1812 1813flto= 1814Common RejectNegative Joined Var(flag_lto) 1815Link-time optimization with number of parallel jobs or jobserver. 1816 1817Enum 1818Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs) 1819 1820EnumValue 1821Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE) 1822 1823EnumValue 1824Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE) 1825 1826EnumValue 1827Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED) 1828 1829EnumValue 1830Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1) 1831 1832EnumValue 1833Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX) 1834 1835flto-partition= 1836Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED) 1837Specify the algorithm to partition symbols and vars at linktime. 1838 1839; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h. 1840flto-compression-level= 1841Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1) IntegerRange(0, 9) 1842-flto-compression-level=<number> Use zlib compression level <number> for IL. 1843 1844flto-odr-type-merging 1845Common Report Var(flag_lto_odr_type_mering) Init(1) 1846Merge C++ types using One Definition Rule. 1847 1848flto-report 1849Common Report Var(flag_lto_report) Init(0) 1850Report various link-time optimization statistics. 1851 1852flto-report-wpa 1853Common Report Var(flag_lto_report_wpa) Init(0) 1854Report various link-time optimization statistics for WPA only. 1855 1856fmath-errno 1857Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined 1858Set errno after built-in math functions. 1859 1860fmax-errors= 1861Common Joined RejectNegative UInteger Var(flag_max_errors) 1862-fmax-errors=<number> Maximum number of errors to report. 1863 1864fmem-report 1865Common Report Var(mem_report) 1866Report on permanent memory allocation. 1867 1868fmem-report-wpa 1869Common Report Var(mem_report_wpa) 1870Report on permanent memory allocation in WPA only. 1871 1872; This will attempt to merge constant section constants, if 1 only 1873; string constants and constants from constant pool, if 2 also constant 1874; variables. 1875fmerge-all-constants 1876Common Report Var(flag_merge_constants,2) Init(1) 1877Attempt to merge identical constants and constant variables. 1878 1879fmerge-constants 1880Common Report Var(flag_merge_constants,1) 1881Attempt to merge identical constants across compilation units. 1882 1883fmerge-debug-strings 1884Common Report Var(flag_merge_debug_strings) Init(1) 1885Attempt to merge identical debug strings across compilation units. 1886 1887fmessage-length= 1888Common RejectNegative Joined UInteger 1889-fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping. 1890 1891fmodulo-sched 1892Common Report Var(flag_modulo_sched) Optimization 1893Perform SMS based modulo scheduling before the first scheduling pass. 1894 1895fmodulo-sched-allow-regmoves 1896Common Report Var(flag_modulo_sched_allow_regmoves) Optimization 1897Perform SMS based modulo scheduling with register moves allowed. 1898 1899fmove-loop-invariants 1900Common Report Var(flag_move_loop_invariants) Optimization 1901Move loop invariant computations out of loops. 1902 1903fdce 1904Common Var(flag_dce) Init(1) Optimization 1905Use the RTL dead code elimination pass. 1906 1907fdse 1908Common Var(flag_dse) Init(1) Optimization 1909Use the RTL dead store elimination pass. 1910 1911freschedule-modulo-scheduled-loops 1912Common Report Var(flag_resched_modulo_sched) Optimization 1913Enable/Disable the traditional scheduling in loops that already passed modulo scheduling. 1914 1915fnon-call-exceptions 1916Common Report Var(flag_non_call_exceptions) Optimization 1917Support synchronous non-call exceptions. 1918 1919foffload= 1920Common Driver Joined MissingArgError(options or targets missing after %qs) 1921-foffload=<targets>=<options> Specify offloading targets and options for them. 1922 1923foffload-abi= 1924Common Joined RejectNegative Enum(offload_abi) Var(flag_offload_abi) Init(OFFLOAD_ABI_UNSET) 1925-foffload-abi=[lp64|ilp32] Set the ABI to use in an offload compiler. 1926 1927Enum 1928Name(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs) 1929 1930EnumValue 1931Enum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32) 1932 1933EnumValue 1934Enum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64) 1935 1936fomit-frame-pointer 1937Common Report Var(flag_omit_frame_pointer) Optimization 1938When possible do not generate stack frames. 1939 1940fopt-info 1941Common Report Var(flag_opt_info) Optimization 1942Enable all optimization info dumps on stderr. 1943 1944fopt-info- 1945Common Joined RejectNegative Var(common_deferred_options) Defer 1946-fopt-info[-<type>=filename] Dump compiler optimization details. 1947 1948foptimize-register-move 1949Common Ignore 1950Does nothing. Preserved for backward compatibility. 1951 1952foptimize-sibling-calls 1953Common Report Var(flag_optimize_sibling_calls) Optimization 1954Optimize sibling and tail recursive calls. 1955 1956fpartial-inlining 1957Common Report Var(flag_partial_inlining) Optimization 1958Perform partial inlining. 1959 1960fpre-ipa-mem-report 1961Common Report Var(pre_ipa_mem_report) 1962Report on memory allocation before interprocedural optimization. 1963 1964fpost-ipa-mem-report 1965Common Report Var(post_ipa_mem_report) 1966Report on memory allocation before interprocedural optimization. 1967 1968fpack-struct 1969Common Report Var(flag_pack_struct) Optimization 1970Pack structure members together without holes. 1971 1972fpack-struct= 1973Common RejectNegative Joined UInteger Optimization 1974-fpack-struct=<number> Set initial maximum structure member alignment. 1975 1976fpcc-struct-return 1977Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN) 1978Return small aggregates in memory, not registers. 1979 1980fpeel-loops 1981Common Report Var(flag_peel_loops) Optimization 1982Perform loop peeling. 1983 1984fpeephole 1985Common Report Var(flag_no_peephole,0) Optimization 1986Enable machine specific peephole optimizations. 1987 1988fpeephole2 1989Common Report Var(flag_peephole2) Optimization 1990Enable an RTL peephole pass before sched2. 1991 1992fPIC 1993Common Report Var(flag_pic,2) Negative(fPIE) Init(-1) 1994Generate position-independent code if possible (large mode). 1995 1996fPIE 1997Common Report Var(flag_pie,2) Negative(fpic) Init(-1) 1998Generate position-independent code for executables if possible (large mode). 1999 2000fpic 2001Common Report Var(flag_pic,1) Negative(fpie) Init(-1) 2002Generate position-independent code if possible (small mode). 2003 2004fpie 2005Common Report Var(flag_pie,1) Negative(fPIC) Init(-1) 2006Generate position-independent code for executables if possible (small mode). 2007 2008fplt 2009Common Report Var(flag_plt) Init(1) Optimization 2010Use PLT for PIC calls (-fno-plt: load the address from GOT at call site). 2011 2012fplugin= 2013Common Joined RejectNegative Var(common_deferred_options) Defer 2014Specify a plugin to load. 2015 2016fplugin-arg- 2017Common Joined RejectNegative Var(common_deferred_options) Defer 2018-fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>. 2019 2020fpredictive-commoning 2021Common Report Var(flag_predictive_commoning) Optimization 2022Run predictive commoning optimization. 2023 2024fprefetch-loop-arrays 2025Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization 2026Generate prefetch instructions, if available, for arrays in loops. 2027 2028fprofile 2029Common Report Var(profile_flag) 2030Enable basic program profiling code. 2031 2032fprofile-abs-path 2033Common Report Var(profile_abs_path_flag) 2034Generate absolute source path names for gcov. 2035 2036fprofile-arcs 2037Common Report Var(profile_arc_flag) 2038Insert arc-based program profiling code. 2039 2040fprofile-dir= 2041Common Joined RejectNegative Var(profile_data_prefix) 2042Set the top-level directory for storing the profile data. 2043The default is 'pwd'. 2044 2045fprofile-correction 2046Common Report Var(flag_profile_correction) 2047Enable correction of flow inconsistent profile data input. 2048 2049fprofile-update= 2050Common Joined RejectNegative Enum(profile_update) Var(flag_profile_update) Init(PROFILE_UPDATE_SINGLE) 2051-fprofile-update=[single|atomic|prefer-atomic] Set the profile update method. 2052 2053Enum 2054Name(profile_update) Type(enum profile_update) UnknownError(unknown profile update method %qs) 2055 2056EnumValue 2057Enum(profile_update) String(single) Value(PROFILE_UPDATE_SINGLE) 2058 2059EnumValue 2060Enum(profile_update) String(atomic) Value(PROFILE_UPDATE_ATOMIC) 2061 2062EnumValue 2063Enum(profile_update) String(prefer-atomic) Value(PROFILE_UPDATE_PREFER_ATOMIC) 2064 2065fprofile-generate 2066Common 2067Enable common options for generating profile info for profile feedback directed optimizations. 2068 2069fprofile-generate= 2070Common Joined RejectNegative 2071Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=. 2072 2073fprofile-use 2074Common Var(flag_profile_use) 2075Enable common options for performing profile feedback directed optimizations. 2076 2077fprofile-use= 2078Common Joined RejectNegative 2079Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=. 2080 2081fprofile-values 2082Common Report Var(flag_profile_values) 2083Insert code to profile values of expressions. 2084 2085fprofile-report 2086Common Report Var(profile_report) 2087Report on consistency of profile. 2088 2089fprofile-reorder-functions 2090Common Report Var(flag_profile_reorder_functions) 2091Enable function reordering that improves code placement. 2092 2093fpatchable-function-entry= 2094Common Joined Optimization 2095Insert NOP instructions at each function entry. 2096 2097frandom-seed 2098Common Var(common_deferred_options) Defer 2099 2100frandom-seed= 2101Common Joined RejectNegative Var(common_deferred_options) Defer 2102-frandom-seed=<string> Make compile reproducible using <string>. 2103 2104; This switch causes the command line that was used to create an 2105; object file to be recorded into the object file. The exact format 2106; of this recording is target and binary file format dependent. 2107; It is related to the -fverbose-asm switch, but that switch only 2108; records information in the assembler output file as comments, so 2109; they never reach the object file. 2110frecord-gcc-switches 2111Common Report Var(flag_record_gcc_switches) 2112Record gcc command line switches in the object file. 2113 2114freg-struct-return 2115Common Report Var(flag_pcc_struct_return,0) Optimization 2116Return small aggregates in registers. 2117 2118fregmove 2119Common Ignore 2120Does nothing. Preserved for backward compatibility. 2121 2122flifetime-dse 2123Common Report Var(flag_lifetime_dse,2) Init(2) Optimization 2124Tell DSE that the storage for a C++ object is dead when the constructor 2125starts and when the destructor finishes. 2126 2127flifetime-dse= 2128Common Joined RejectNegative UInteger Var(flag_lifetime_dse) Optimization IntegerRange(0, 2) 2129 2130flive-range-shrinkage 2131Common Report Var(flag_live_range_shrinkage) Init(0) Optimization 2132Relief of register pressure through live range shrinkage. 2133 2134frename-registers 2135Common Report Var(flag_rename_registers) Init(2) Optimization 2136Perform a register renaming optimization pass. 2137 2138fschedule-fusion 2139Common Report Var(flag_schedule_fusion) Init(2) Optimization 2140Perform a target dependent instruction fusion optimization pass. 2141 2142freorder-blocks 2143Common Report Var(flag_reorder_blocks) Optimization 2144Reorder basic blocks to improve code placement. 2145 2146freorder-blocks-algorithm= 2147Common Joined RejectNegative Enum(reorder_blocks_algorithm) Var(flag_reorder_blocks_algorithm) Init(REORDER_BLOCKS_ALGORITHM_SIMPLE) Optimization 2148-freorder-blocks-algorithm=[simple|stc] Set the used basic block reordering algorithm. 2149 2150Enum 2151Name(reorder_blocks_algorithm) Type(enum reorder_blocks_algorithm) UnknownError(unknown basic block reordering algorithm %qs) 2152 2153EnumValue 2154Enum(reorder_blocks_algorithm) String(simple) Value(REORDER_BLOCKS_ALGORITHM_SIMPLE) 2155 2156EnumValue 2157Enum(reorder_blocks_algorithm) String(stc) Value(REORDER_BLOCKS_ALGORITHM_STC) 2158 2159freorder-blocks-and-partition 2160Common Report Var(flag_reorder_blocks_and_partition) Optimization 2161Reorder basic blocks and partition into hot and cold sections. 2162 2163freorder-functions 2164Common Report Var(flag_reorder_functions) Optimization 2165Reorder functions to improve code placement. 2166 2167frerun-cse-after-loop 2168Common Report Var(flag_rerun_cse_after_loop) Optimization 2169Add a common subexpression elimination pass after loop optimizations. 2170 2171frerun-loop-opt 2172Common Ignore 2173Does nothing. Preserved for backward compatibility. 2174 2175frounding-math 2176Common Report Var(flag_rounding_math) Optimization SetByCombined 2177Disable optimizations that assume default FP rounding behavior. 2178 2179fsched-interblock 2180Common Report Var(flag_schedule_interblock) Init(1) Optimization 2181Enable scheduling across basic blocks. 2182 2183fsched-pressure 2184Common Report Var(flag_sched_pressure) Init(0) Optimization 2185Enable register pressure sensitive insn scheduling. 2186 2187fsched-spec 2188Common Report Var(flag_schedule_speculative) Init(1) Optimization 2189Allow speculative motion of non-loads. 2190 2191fsched-spec-load 2192Common Report Var(flag_schedule_speculative_load) Optimization 2193Allow speculative motion of some loads. 2194 2195fsched-spec-load-dangerous 2196Common Report Var(flag_schedule_speculative_load_dangerous) Optimization 2197Allow speculative motion of more loads. 2198 2199fsched-verbose= 2200Common RejectNegative Joined UInteger Var(sched_verbose_param) Init(1) 2201-fsched-verbose=<number> Set the verbosity level of the scheduler. 2202 2203fsched2-use-superblocks 2204Common Report Var(flag_sched2_use_superblocks) Optimization 2205If scheduling post reload, do superblock scheduling. 2206 2207fsched2-use-traces 2208Common Ignore 2209Does nothing. Preserved for backward compatibility. 2210 2211fschedule-insns 2212Common Report Var(flag_schedule_insns) Optimization 2213Reschedule instructions before register allocation. 2214 2215fschedule-insns2 2216Common Report Var(flag_schedule_insns_after_reload) Optimization 2217Reschedule instructions after register allocation. 2218 2219; This flag should be on when a target implements non-trivial 2220; scheduling hooks, maybe saving some information for its own sake. 2221; On IA64, for example, this is used for correct bundling. 2222fselective-scheduling 2223Common Report Var(flag_selective_scheduling) Optimization 2224Schedule instructions using selective scheduling algorithm. 2225 2226fselective-scheduling2 2227Common Report Var(flag_selective_scheduling2) Optimization 2228Run selective scheduling after reload. 2229 2230fself-test= 2231Common Undocumented Joined Var(flag_self_test) 2232Run self-tests, using the given path to locate test files. 2233 2234fsel-sched-pipelining 2235Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization 2236Perform software pipelining of inner loops during selective scheduling. 2237 2238fsel-sched-pipelining-outer-loops 2239Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization 2240Perform software pipelining of outer loops during selective scheduling. 2241 2242fsel-sched-reschedule-pipelined 2243Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization 2244Reschedule pipelined regions without pipelining. 2245 2246fsemantic-interposition 2247Common Report Var(flag_semantic_interposition) Init(1) 2248Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker. 2249 2250; sched_stalled_insns means that insns can be moved prematurely from the queue 2251; of stalled insns into the ready list. 2252fsched-stalled-insns 2253Common Report Var(flag_sched_stalled_insns) Optimization UInteger 2254Allow premature scheduling of queued insns. 2255 2256fsched-stalled-insns= 2257Common RejectNegative Joined UInteger Optimization 2258-fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled. 2259 2260; sched_stalled_insns_dep controls how many recently scheduled cycles will 2261; be examined for a dependency on a stalled insn that is candidate for 2262; premature removal from the queue of stalled insns into the ready list (has 2263; an effect only if the flag 'sched_stalled_insns' is set). 2264fsched-stalled-insns-dep 2265Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger 2266Set dependence distance checking in premature scheduling of queued insns. 2267 2268fsched-stalled-insns-dep= 2269Common RejectNegative Joined UInteger Optimization 2270-fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns. 2271 2272fsched-group-heuristic 2273Common Report Var(flag_sched_group_heuristic) Init(1) Optimization 2274Enable the group heuristic in the scheduler. 2275 2276fsched-critical-path-heuristic 2277Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization 2278Enable the critical path heuristic in the scheduler. 2279 2280fsched-spec-insn-heuristic 2281Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization 2282Enable the speculative instruction heuristic in the scheduler. 2283 2284fsched-rank-heuristic 2285Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization 2286Enable the rank heuristic in the scheduler. 2287 2288fsched-last-insn-heuristic 2289Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization 2290Enable the last instruction heuristic in the scheduler. 2291 2292fsched-dep-count-heuristic 2293Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization 2294Enable the dependent count heuristic in the scheduler. 2295 2296fsection-anchors 2297Common Report Var(flag_section_anchors) Optimization 2298Access data in the same section from shared anchor points. 2299 2300fsee 2301Common Ignore 2302Does nothing. Preserved for backward compatibility. 2303 2304fzee 2305Common Ignore 2306Does nothing. Preserved for backward compatibility. 2307 2308free 2309Common Report Var(flag_ree) Init(0) 2310Turn on Redundant Extensions Elimination pass. 2311 2312fshow-column 2313Common Report Var(flag_show_column) Init(1) 2314Show column numbers in diagnostics, when available. Default on. 2315 2316fshrink-wrap 2317Common Report Var(flag_shrink_wrap) Optimization 2318Emit function prologues only before parts of the function that need it, 2319rather than at the top of the function. 2320 2321fshrink-wrap-separate 2322Common Report Var(flag_shrink_wrap_separate) Init(1) Optimization 2323Shrink-wrap parts of the prologue and epilogue separately. 2324 2325fsignaling-nans 2326Common Report Var(flag_signaling_nans) Optimization SetByCombined 2327Disable optimizations observable by IEEE signaling NaNs. 2328 2329fsigned-zeros 2330Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined 2331Disable floating point optimizations that ignore the IEEE signedness of zero. 2332 2333fsingle-precision-constant 2334Common Report Var(flag_single_precision_constant) Optimization 2335Convert floating point constants to single precision constants. 2336 2337fsplit-ivs-in-unroller 2338Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization 2339Split lifetimes of induction variables when loops are unrolled. 2340 2341fsplit-stack 2342Common Report Var(flag_split_stack) Init(-1) 2343Generate discontiguous stack frames. 2344 2345fsplit-wide-types 2346Common Report Var(flag_split_wide_types) Optimization 2347Split wide types into independent registers. 2348 2349fssa-backprop 2350Common Report Var(flag_ssa_backprop) Init(1) Optimization 2351Enable backward propagation of use properties at the SSA level. 2352 2353fssa-phiopt 2354Common Report Var(flag_ssa_phiopt) Optimization 2355Optimize conditional patterns using SSA PHI nodes. 2356 2357fstdarg-opt 2358Common Report Var(flag_stdarg_opt) Init(1) Optimization 2359Optimize amount of stdarg registers saved to stack at start of function. 2360 2361fvariable-expansion-in-unroller 2362Common Report Var(flag_variable_expansion_in_unroller) Optimization 2363Apply variable expansion when loops are unrolled. 2364 2365fstack-check= 2366Common Report RejectNegative Joined Optimization 2367-fstack-check=[no|generic|specific] Insert stack checking code into the program. 2368 2369fstack-check 2370Common Alias(fstack-check=, specific, no) 2371Insert stack checking code into the program. Same as -fstack-check=specific. 2372 2373fstack-clash-protection 2374Common Report Var(flag_stack_clash_protection) Optimization 2375Insert code to probe each page of stack space as it is allocated to protect 2376from stack-clash style attacks. 2377 2378fstack-limit 2379Common Var(common_deferred_options) Defer 2380 2381fstack-limit-register= 2382Common RejectNegative Joined Var(common_deferred_options) Defer 2383-fstack-limit-register=<register> Trap if the stack goes past <register>. 2384 2385fstack-limit-symbol= 2386Common RejectNegative Joined Var(common_deferred_options) Defer 2387-fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>. 2388 2389fstack-protector 2390Common Report Var(flag_stack_protect, 1) Init(-1) Optimization 2391Use propolice as a stack protection method. 2392 2393fstack-protector-all 2394Common Report RejectNegative Var(flag_stack_protect, 2) Init(-1) Optimization 2395Use a stack protection method for every function. 2396 2397fstack-protector-strong 2398Common Report RejectNegative Var(flag_stack_protect, 3) Init(-1) Optimization 2399Use a smart stack protection method for certain functions. 2400 2401fstack-protector-explicit 2402Common Report RejectNegative Var(flag_stack_protect, 4) Optimization 2403Use stack protection method only for functions with the stack_protect attribute. 2404 2405fstack-usage 2406Common RejectNegative Var(flag_stack_usage) 2407Output stack usage information on a per-function basis. 2408 2409fstrength-reduce 2410Common Ignore 2411Does nothing. Preserved for backward compatibility. 2412 2413; Nonzero if we should do (language-dependent) alias analysis. 2414; Typically, this analysis will assume that expressions of certain 2415; types do not alias expressions of certain other types. Only used 2416; if alias analysis (in general) is enabled. 2417fstrict-aliasing 2418Common Report Var(flag_strict_aliasing) Optimization 2419Assume strict aliasing rules apply. 2420 2421fstrict-overflow 2422Common Report 2423Treat signed overflow as undefined. Negated as -fwrapv -fwrapv-pointer. 2424 2425fsync-libcalls 2426Common Report Var(flag_sync_libcalls) Init(1) 2427Implement __atomic operations via libcalls to legacy __sync functions. 2428 2429fsyntax-only 2430Common Report Var(flag_syntax_only) 2431Check for syntax errors, then stop. 2432 2433ftest-coverage 2434Common Report Var(flag_test_coverage) 2435Create data files needed by \"gcov\". 2436 2437fthread-jumps 2438Common Report Var(flag_thread_jumps) Optimization 2439Perform jump threading optimizations. 2440 2441ftime-report 2442Common Report Var(time_report) 2443Report the time taken by each compiler pass. 2444 2445ftime-report-details 2446Common Report Var(time_report_details) 2447Record times taken by sub-phases separately. 2448 2449ftls-model= 2450Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC) 2451-ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model. 2452 2453Enum 2454Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs) 2455 2456EnumValue 2457Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC) 2458 2459EnumValue 2460Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC) 2461 2462EnumValue 2463Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC) 2464 2465EnumValue 2466Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC) 2467 2468ftoplevel-reorder 2469Common Report Var(flag_toplevel_reorder) Init(2) 2470Reorder top level functions, variables, and asms. 2471 2472ftracer 2473Common Report Var(flag_tracer) Optimization 2474Perform superblock formation via tail duplication. 2475 2476ftrampolines 2477Common Report Var(flag_trampolines) Init(0) 2478For targets that normally need trampolines for nested functions, always 2479generate them instead of using descriptors. 2480 2481; Zero means that floating-point math operations cannot generate a 2482; (user-visible) trap. This is the case, for example, in nonstop 2483; IEEE 754 arithmetic. 2484ftrapping-math 2485Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined 2486Assume floating-point operations can trap. 2487 2488ftrapv 2489Common Report Var(flag_trapv) Optimization 2490Trap for signed overflow in addition, subtraction and multiplication. 2491 2492ftree-ccp 2493Common Report Var(flag_tree_ccp) Optimization 2494Enable SSA-CCP optimization on trees. 2495 2496ftree-bit-ccp 2497Common Report Var(flag_tree_bit_ccp) Optimization 2498Enable SSA-BIT-CCP optimization on trees. 2499 2500ftree-store-ccp 2501Common Ignore 2502Does nothing. Preserved for backward compatibility. 2503 2504ftree-ch 2505Common Report Var(flag_tree_ch) Optimization 2506Enable loop header copying on trees. 2507 2508ftree-coalesce-inlined-vars 2509Common Ignore RejectNegative 2510Does nothing. Preserved for backward compatibility. 2511 2512ftree-coalesce-vars 2513Common Report Var(flag_tree_coalesce_vars) Optimization 2514Enable SSA coalescing of user variables. 2515 2516ftree-copyrename 2517Common Ignore 2518Does nothing. Preserved for backward compatibility. 2519 2520ftree-copy-prop 2521Common Report Var(flag_tree_copy_prop) Optimization 2522Enable copy propagation on trees. 2523 2524ftree-store-copy-prop 2525Common Ignore 2526Does nothing. Preserved for backward compatibility. 2527 2528ftree-cselim 2529Common Report Var(flag_tree_cselim) Init(2) Optimization 2530Transform condition stores into unconditional ones. 2531 2532ftree-switch-conversion 2533Common Report Var(flag_tree_switch_conversion) Optimization 2534Perform conversions of switch initializations. 2535 2536ftree-dce 2537Common Report Var(flag_tree_dce) Optimization 2538Enable SSA dead code elimination optimization on trees. 2539 2540ftree-dominator-opts 2541Common Report Var(flag_tree_dom) Optimization 2542Enable dominator optimizations. 2543 2544ftree-tail-merge 2545Common Report Var(flag_tree_tail_merge) Optimization 2546Enable tail merging on trees. 2547 2548ftree-dse 2549Common Report Var(flag_tree_dse) Optimization 2550Enable dead store elimination. 2551 2552ftree-forwprop 2553Common Report Var(flag_tree_forwprop) Init(1) Optimization 2554Enable forward propagation on trees. 2555 2556ftree-fre 2557Common Report Var(flag_tree_fre) Optimization 2558Enable Full Redundancy Elimination (FRE) on trees. 2559 2560foptimize-strlen 2561Common Report Var(flag_optimize_strlen) Optimization 2562Enable string length optimizations on trees. 2563 2564fisolate-erroneous-paths-dereference 2565Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization 2566Detect paths that trigger erroneous or undefined behavior due to 2567dereferencing a null pointer. Isolate those paths from the main control 2568flow and turn the statement with erroneous or undefined behavior into a trap. 2569 2570fisolate-erroneous-paths-attribute 2571Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization 2572Detect paths that trigger erroneous or undefined behavior due to a null value 2573being used in a way forbidden by a returns_nonnull or nonnull 2574attribute. Isolate those paths from the main control flow and turn the 2575statement with erroneous or undefined behavior into a trap. 2576 2577ftree-loop-distribution 2578Common Report Var(flag_tree_loop_distribution) Optimization 2579Enable loop distribution on trees. 2580 2581ftree-loop-distribute-patterns 2582Common Report Var(flag_tree_loop_distribute_patterns) Optimization 2583Enable loop distribution for patterns transformed into a library call. 2584 2585ftree-loop-im 2586Common Report Var(flag_tree_loop_im) Init(1) Optimization 2587Enable loop invariant motion on trees. 2588 2589ftree-loop-linear 2590Common Alias(floop-nest-optimize) 2591Enable loop nest transforms. Same as -floop-nest-optimize. 2592 2593ftree-loop-ivcanon 2594Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization 2595Create canonical induction variables in loops. 2596 2597ftree-loop-optimize 2598Common Report Var(flag_tree_loop_optimize) Init(1) Optimization 2599Enable loop optimizations on tree level. 2600 2601ftree-parallelize-loops= 2602Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) Optimization 2603-ftree-parallelize-loops=<number> Enable automatic parallelization of loops. 2604 2605ftree-phiprop 2606Common Report Var(flag_tree_phiprop) Init(1) Optimization 2607Enable hoisting loads from conditional pointers. 2608 2609ftree-pre 2610Common Report Var(flag_tree_pre) Optimization 2611Enable SSA-PRE optimization on trees. 2612 2613ftree-partial-pre 2614Common Report Var(flag_tree_partial_pre) Optimization 2615In SSA-PRE optimization on trees, enable partial-partial redundancy elimination. 2616 2617ftree-pta 2618Common Report Var(flag_tree_pta) Optimization 2619Perform function-local points-to analysis on trees. 2620 2621ftree-reassoc 2622Common Report Var(flag_tree_reassoc) Init(1) Optimization 2623Enable reassociation on tree level. 2624 2625ftree-salias 2626Common Ignore 2627Does nothing. Preserved for backward compatibility. 2628 2629ftree-sink 2630Common Report Var(flag_tree_sink) Optimization 2631Enable SSA code sinking on trees. 2632 2633ftree-slsr 2634Common Report Var(flag_tree_slsr) Optimization 2635Perform straight-line strength reduction. 2636 2637ftree-sra 2638Common Report Var(flag_tree_sra) Optimization 2639Perform scalar replacement of aggregates. 2640 2641ftree-ter 2642Common Report Var(flag_tree_ter) Optimization 2643Replace temporary expressions in the SSA->normal pass. 2644 2645ftree-lrs 2646Common Report Var(flag_tree_live_range_split) Optimization 2647Perform live range splitting during the SSA->normal pass. 2648 2649ftree-vrp 2650Common Report Var(flag_tree_vrp) Init(0) Optimization 2651Perform Value Range Propagation on trees. 2652 2653fsplit-paths 2654Common Report Var(flag_split_paths) Init(0) Optimization 2655Split paths leading to loop backedges. 2656 2657funconstrained-commons 2658Common Var(flag_unconstrained_commons) Optimization 2659Assume common declarations may be overridden with ones with a larger 2660trailing array. 2661 2662funit-at-a-time 2663Common Report Var(flag_unit_at_a_time) Init(1) 2664Compile whole compilation unit at a time. 2665 2666funroll-loops 2667Common Report Var(flag_unroll_loops) Optimization 2668Perform loop unrolling when iteration count is known. 2669 2670funroll-all-loops 2671Common Report Var(flag_unroll_all_loops) Optimization 2672Perform loop unrolling for all loops. 2673 2674; Nonzero means that loop optimizer may assume that the induction variables 2675; that control loops do not overflow and that the loops with nontrivial 2676; exit condition are not infinite 2677funsafe-loop-optimizations 2678Common Ignore 2679Does nothing. Preserved for backward compatibility. 2680 2681fassociative-math 2682Common Report Var(flag_associative_math) SetByCombined Optimization 2683Allow optimization for floating-point arithmetic which may change the 2684result of the operation due to rounding. 2685 2686freciprocal-math 2687Common Report Var(flag_reciprocal_math) SetByCombined Optimization 2688Same as -fassociative-math for expressions which include division. 2689 2690; Nonzero means that unsafe floating-point math optimizations are allowed 2691; for the sake of speed. IEEE compliance is not guaranteed, and operations 2692; are allowed to assume that their arguments and results are "normal" 2693; (e.g., nonnegative for SQRT). 2694funsafe-math-optimizations 2695Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined 2696Allow math optimizations that may violate IEEE or ISO standards. 2697 2698funswitch-loops 2699Common Report Var(flag_unswitch_loops) Optimization 2700Perform loop unswitching. 2701 2702fsplit-loops 2703Common Report Var(flag_split_loops) Optimization 2704Perform loop splitting. 2705 2706funwind-tables 2707Common Report Var(flag_unwind_tables) Optimization 2708Just generate unwind tables for exception handling. 2709 2710fuse-ld=bfd 2711Common Driver Negative(fuse-ld=gold) 2712Use the bfd linker instead of the default linker. 2713 2714fuse-ld=gold 2715Common Driver Negative(fuse-ld=bfd) 2716Use the gold linker instead of the default linker. 2717 2718fuse-linker-plugin 2719Common Undocumented Var(flag_use_linker_plugin) 2720 2721; Positive if we should track variables, negative if we should run 2722; the var-tracking pass only to discard debug annotations, zero if 2723; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it 2724; will be set according to optimize, debug_info_level and debug_hooks 2725; in process_options (). 2726fvar-tracking 2727Common Report Var(flag_var_tracking) Init(2) PerFunction 2728Perform variable tracking. 2729 2730; Positive if we should track variables at assignments, negative if 2731; we should run the var-tracking pass only to discard debug 2732; annotations. When flag_var_tracking_assignments == 2733; AUTODETECT_VALUE it will be set according to flag_var_tracking. 2734fvar-tracking-assignments 2735Common Report Var(flag_var_tracking_assignments) Init(2) PerFunction 2736Perform variable tracking by annotating assignments. 2737 2738; Nonzero if we should toggle flag_var_tracking_assignments after 2739; processing options and computing its default. */ 2740fvar-tracking-assignments-toggle 2741Common Report Var(flag_var_tracking_assignments_toggle) PerFunction 2742Toggle -fvar-tracking-assignments. 2743 2744; Positive if we should track uninitialized variables, negative if 2745; we should run the var-tracking pass only to discard debug 2746; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it 2747; will be set according to flag_var_tracking. 2748fvar-tracking-uninit 2749Common Report Var(flag_var_tracking_uninit) PerFunction 2750Perform variable tracking and also tag variables that are uninitialized. 2751 2752; Alias to enable both -ftree-loop-vectorize and -ftree-slp-vectorize. 2753ftree-vectorize 2754Common Report Optimization 2755Enable vectorization on trees. 2756 2757ftree-vectorizer-verbose= 2758Common Joined RejectNegative Ignore 2759Does nothing. Preserved for backward compatibility. 2760 2761ftree-loop-vectorize 2762Common Report Var(flag_tree_loop_vectorize) Optimization EnabledBy(ftree-vectorize) 2763Enable loop vectorization on trees. 2764 2765ftree-slp-vectorize 2766Common Report Var(flag_tree_slp_vectorize) Optimization EnabledBy(ftree-vectorize) 2767Enable basic block vectorization (SLP) on trees. 2768 2769fvect-cost-model= 2770Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization 2771Specifies the cost model for vectorization. 2772-fvect-cost-model=[unlimited|dynamic|cheap] Specifies the cost model for vectorization. 2773 2774fsimd-cost-model= 2775Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization 2776-fsimd-cost-model=[unlimited|dynamic|cheap] Specifies the vectorization cost model for code marked with a simd directive. 2777 2778Enum 2779Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs) 2780 2781EnumValue 2782Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED) 2783 2784EnumValue 2785Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC) 2786 2787EnumValue 2788Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP) 2789 2790fvect-cost-model 2791Common Alias(fvect-cost-model=,dynamic,unlimited) 2792Enables the dynamic vectorizer cost model. Preserved for backward compatibility. 2793 2794ftree-vect-loop-version 2795Common Ignore 2796Does nothing. Preserved for backward compatibility. 2797 2798ftree-scev-cprop 2799Common Report Var(flag_tree_scev_cprop) Init(1) Optimization 2800Enable copy propagation of scalar-evolution information. 2801 2802; -fverbose-asm causes extra commentary information to be produced in 2803; the generated assembly code (to make it more readable). This option 2804; is generally only of use to those who actually need to read the 2805; generated assembly code (perhaps while debugging the compiler itself). 2806; -fno-verbose-asm, the default, causes the extra information 2807; to not be added and is useful when comparing two assembler files. 2808fverbose-asm 2809Common Report Var(flag_verbose_asm) 2810Add extra commentary to assembler output. 2811 2812fvisibility= 2813Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT) 2814-fvisibility=[default|internal|hidden|protected] Set the default symbol visibility. 2815 2816Enum 2817Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs) 2818 2819EnumValue 2820Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT) 2821 2822EnumValue 2823Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL) 2824 2825EnumValue 2826Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN) 2827 2828EnumValue 2829Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED) 2830 2831fvtable-verify= 2832Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY) 2833Validate vtable pointers before using them. 2834 2835Enum 2836Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs) 2837 2838EnumValue 2839Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY) 2840 2841EnumValue 2842Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY) 2843 2844EnumValue 2845Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY) 2846 2847fvtv-counts 2848Common Var(flag_vtv_counts) 2849Output vtable verification counters. 2850 2851fvtv-debug 2852Common Var(flag_vtv_debug) 2853Output vtable verification pointer sets information. 2854 2855fvpt 2856Common Report Var(flag_value_profile_transformations) Optimization 2857Use expression value profiles in optimizations. 2858 2859fweb 2860Common Report Var(flag_web) Init(2) Optimization 2861Construct webs and split unrelated uses of single variable. 2862 2863ftree-builtin-call-dce 2864Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization 2865Enable conditional dead code elimination for builtin calls. 2866 2867fwhole-program 2868Common Report Var(flag_whole_program) Init(0) 2869Perform whole program optimizations. 2870 2871fwrapv-pointer 2872Common Report Var(flag_wrapv_pointer) Optimization 2873Assume pointer overflow wraps around. 2874 2875fwrapv 2876Common Report Var(flag_wrapv) Optimization 2877Assume signed arithmetic overflow wraps around. 2878 2879fzero-initialized-in-bss 2880Common Report Var(flag_zero_initialized_in_bss) Init(1) 2881Put zero initialized data in the bss section. 2882 2883g 2884Common Driver RejectNegative JoinedOrMissing 2885Generate debug information in default format. 2886 2887gas-loc-support 2888Common Driver Var(dwarf2out_as_loc_support) Init(2) 2889Assume assembler support for (DWARF2+) .loc directives 2890 2891gas-locview-support 2892Common Driver Var(dwarf2out_as_locview_support) Init(2) 2893Assume assembler support for view in (DWARF2+) .loc directives 2894 2895gcoff 2896Common Driver Ignore Warn(switch %qs no longer supported) 2897Does nothing. Preserved for backward compatibility. 2898 2899gcoff1 2900Common Driver Ignore Warn(switch %qs no longer supported) 2901Does nothing. Preserved for backward compatibility. 2902 2903gcoff2 2904Common Driver Ignore Warn(switch %qs no longer supported) 2905Does nothing. Preserved for backward compatibility. 2906 2907gcoff3 2908Common Driver Ignore Warn(switch %qs no longer supported) 2909Does nothing. Preserved for backward compatibility. 2910 2911gcolumn-info 2912Common Driver Var(debug_column_info,1) Init(1) 2913Record DW_AT_decl_column and DW_AT_call_column in DWARF. 2914 2915gdwarf 2916Common Driver JoinedOrMissing Negative(gdwarf-) 2917Generate debug information in default version of DWARF format. 2918 2919gdwarf- 2920Common Driver Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs) 2921Generate debug information in DWARF v2 (or later) format. 2922 2923ggdb 2924Common Driver JoinedOrMissing 2925Generate debug information in default extended format. 2926 2927ginline-points 2928Common Driver Var(debug_inline_points) Init(2) 2929Generate extended entry point information for inlined functions 2930 2931ginternal-reset-location-views 2932Common Driver Var(debug_internal_reset_location_views) Init(2) 2933Compute locview reset points based on insn length estimates 2934 2935gno- 2936RejectNegative Joined Undocumented 2937; Catch the gno- prefix, so it doesn't backtrack to g<level>. 2938 2939gno-pubnames 2940Common Driver Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1) 2941Don't generate DWARF pubnames and pubtypes sections. 2942 2943gpubnames 2944Common Driver Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1) 2945Generate DWARF pubnames and pubtypes sections. 2946 2947ggnu-pubnames 2948Common Driver Negative(gno-pubnames) Var(debug_generate_pub_sections, 2) 2949Generate DWARF pubnames and pubtypes sections with GNU extensions. 2950 2951grecord-gcc-switches 2952Common Driver Var(dwarf_record_gcc_switches) Init(1) 2953Record gcc command line switches in DWARF DW_AT_producer. 2954 2955gsplit-dwarf 2956Common Driver Var(dwarf_split_debug_info) Init(0) 2957Generate debug information in separate .dwo files. 2958 2959gstabs 2960Common Driver JoinedOrMissing Negative(gstabs+) 2961Generate debug information in STABS format. 2962 2963gstabs+ 2964Common Driver JoinedOrMissing Negative(gvms) 2965Generate debug information in extended STABS format. 2966 2967gstatement-frontiers 2968Common Driver Var(debug_nonbind_markers_p) Init(2) 2969Emit progressive recommended breakpoint locations. 2970 2971gstrict-dwarf 2972Common Driver Report Var(dwarf_strict) Init(0) 2973Don't emit DWARF additions beyond selected version. 2974 2975gtoggle 2976Common Driver Report Var(flag_gtoggle) 2977Toggle debug information generation. 2978 2979gvariable-location-views 2980Common Driver Var(debug_variable_location_views, 1) Init(2) 2981Augment variable location lists with progressive views. 2982 2983gvariable-location-views=incompat5 2984Common Driver RejectNegative Var(debug_variable_location_views, -1) Init(2) 2985 2986gvms 2987Common Driver JoinedOrMissing Negative(gxcoff) 2988Generate debug information in VMS format. 2989 2990gxcoff 2991Common Driver JoinedOrMissing Negative(gxcoff+) 2992Generate debug information in XCOFF format. 2993 2994gxcoff+ 2995Common Driver JoinedOrMissing Negative(gdwarf) 2996Generate debug information in extended XCOFF format. 2997 2998Enum 2999Name(compressed_debug_sections) Type(int) 3000 3001; Since -gz= is completely handled in specs, the values aren't used and we 3002; assign arbitrary constants. 3003EnumValue 3004Enum(compressed_debug_sections) String(none) Value(0) 3005 3006EnumValue 3007Enum(compressed_debug_sections) String(zlib) Value(1) 3008 3009EnumValue 3010Enum(compressed_debug_sections) String(zlib-gnu) Value(2) 3011 3012gz 3013Common Driver 3014Generate compressed debug sections. 3015 3016gz= 3017Common Driver RejectNegative Joined Enum(compressed_debug_sections) 3018-gz=<format> Generate compressed debug sections in format <format>. 3019 3020h 3021Driver Joined Separate 3022 3023iplugindir= 3024Common Joined Var(plugindir_string) Init(0) 3025-iplugindir=<dir> Set <dir> to be the default plugin directory. 3026 3027imultiarch 3028Common Joined Separate RejectDriver Var(imultiarch) Init(0) 3029-imultiarch <dir> Set <dir> to be the multiarch include subdirectory. 3030 3031l 3032Driver Joined Separate 3033 3034n 3035Driver 3036 3037no-canonical-prefixes 3038Driver 3039 3040nodefaultlibs 3041Driver 3042 3043nostartfiles 3044Driver 3045 3046nostdlib 3047Driver 3048 3049o 3050Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs) 3051-o <file> Place output into <file>. 3052 3053p 3054Common Var(profile_flag) 3055Enable function profiling. 3056 3057pass-exit-codes 3058Driver Var(pass_exit_codes) 3059 3060pedantic 3061Common Alias(Wpedantic) 3062 3063pedantic-errors 3064Common Var(flag_pedantic_errors) 3065Like -pedantic but issue them as errors. 3066 3067pg 3068Driver 3069 3070pipe 3071Driver Var(use_pipes) 3072 3073print-file-name= 3074Driver JoinedOrMissing Var(print_file_name) 3075 3076print-libgcc-file-name 3077Driver 3078 3079print-multi-directory 3080Driver Var(print_multi_directory) 3081 3082print-multi-lib 3083Driver Var(print_multi_lib) 3084 3085print-multi-os-directory 3086Driver Var(print_multi_os_directory) 3087 3088print-multiarch 3089Driver Var(print_multiarch) 3090 3091print-prog-name= 3092Driver JoinedOrMissing Var(print_prog_name) 3093 3094print-search-dirs 3095Driver Var(print_search_dirs) 3096 3097print-sysroot 3098Driver Var(print_sysroot) 3099 3100print-sysroot-headers-suffix 3101Driver Var(print_sysroot_headers_suffix) 3102 3103quiet 3104Common Var(quiet_flag) RejectDriver 3105Do not display functions compiled or elapsed time. 3106 3107r 3108Driver 3109 3110s 3111Driver 3112 3113save-temps 3114Driver 3115 3116save-temps= 3117Driver Joined 3118 3119t 3120Driver 3121 3122time 3123Driver Var(report_times) 3124 3125time= 3126Driver JoinedOrMissing 3127 3128u 3129Driver Joined Separate 3130 3131undef 3132Driver 3133; C option, but driver must not handle as "-u ndef". 3134 3135v 3136Common Driver Var(verbose_flag) 3137Enable verbose output. 3138 3139version 3140Common Var(version_flag) RejectDriver 3141Display the compiler's version. 3142 3143w 3144Common Var(inhibit_warnings) 3145Suppress warnings. 3146 3147wrapper 3148Driver Separate Var(wrapper_string) 3149 3150x 3151Driver Joined Separate 3152 3153shared 3154Driver RejectNegative Negative(static-pie) 3155Create a shared library. 3156 3157shared-libgcc 3158Driver 3159 3160specs 3161Driver Separate Alias(specs=) 3162 3163specs= 3164Driver Joined 3165 3166static 3167Driver 3168 3169static-libgcc 3170Driver 3171 3172static-libgfortran 3173Driver 3174; Documented for Fortran, but always accepted by driver. 3175 3176static-libstdc++ 3177Driver 3178 3179static-libgo 3180Driver 3181; Documented for Go, but always accepted by driver. 3182 3183static-libasan 3184Driver 3185 3186static-libtsan 3187Driver 3188 3189static-liblsan 3190Driver 3191 3192static-libubsan 3193Driver 3194 3195symbolic 3196Driver 3197 3198no-pie 3199Driver RejectNegative Negative(shared) 3200Don't create a dynamically linked position independent executable. 3201 3202pie 3203Driver RejectNegative Negative(no-pie) 3204Create a dynamically linked position independent executable. 3205 3206static-pie 3207Driver RejectNegative Negative(pie) 3208Create a static position independent executable. 3209 3210z 3211Driver Joined Separate 3212 3213fipa-ra 3214Common Report Var(flag_ipa_ra) Optimization 3215Use caller save register across calls if possible. 3216 3217; This comment is to ensure we retain the blank line above. 3218