1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- E R R O U T -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2013, Free Software Foundation, Inc. -- 10-- -- 11-- GNAT is free software; you can redistribute it and/or modify it under -- 12-- terms of the GNU General Public License as published by the Free Soft- -- 13-- ware Foundation; either version 3, or (at your option) any later ver- -- 14-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 15-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 16-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- 17-- for more details. You should have received a copy of the GNU General -- 18-- Public License distributed with GNAT; see file COPYING3. If not, go to -- 19-- http://www.gnu.org/licenses for a complete copy of the license. -- 20-- -- 21-- GNAT was originally developed by the GNAT team at New York University. -- 22-- Extensive contributions were provided by Ada Core Technologies Inc. -- 23-- -- 24------------------------------------------------------------------------------ 25 26-- This package contains the routines to output error messages. They are 27-- basically system independent, however in some environments, e.g. when the 28-- parser is embedded into an editor, it may be appropriate to replace the 29-- implementation of this package. 30 31with Err_Vars; 32with Erroutc; 33with Namet; use Namet; 34with Table; 35with Types; use Types; 36with Uintp; use Uintp; 37 38with System; 39 40package Errout is 41 42 Current_Error_Source_File : Source_File_Index 43 renames Err_Vars.Current_Error_Source_File; 44 -- Id of current messages. Used to post file name when unit changes. This 45 -- is initialized to Main_Source_File at the start of a compilation, which 46 -- means that no file names will be output unless there are errors in 47 -- units other than the main unit. However, if the main unit has a pragma 48 -- Source_Reference line, then this is initialized to No_Source_File, to 49 -- force an initial reference to the real source file name. 50 51 Raise_Exception_On_Error : Nat renames Err_Vars.Raise_Exception_On_Error; 52 -- If this value is non-zero, then any attempt to generate an error 53 -- message raises the exception Error_Msg_Exception, and the error message 54 -- is not output. This is used for defending against junk resulting from 55 -- illegalities, and also for substitution of more appropriate error 56 -- messages from higher semantic levels. It is a counter so that the 57 -- increment/decrement protocol nests neatly. 58 59 Error_Msg_Exception : exception renames Err_Vars.Error_Msg_Exception; 60 -- Exception raised if Raise_Exception_On_Error is true 61 62 Warning_Doc_Switch : Boolean renames Err_Vars.Warning_Doc_Switch; 63 -- If this is set True, then the ??/?x?/?X? sequences in error messages 64 -- are active (see errout.ads for details). If this switch is False, then 65 -- these sequences are ignored (i.e. simply equivalent to a single ?). The 66 -- -gnatw.d switch sets this flag True, -gnatw.D sets this flag False. 67 68 ----------------------------------- 69 -- Suppression of Error Messages -- 70 ----------------------------------- 71 72 -- In an effort to reduce the impact of redundant error messages, the 73 -- error output routines in this package normally suppress certain 74 -- classes of messages as follows: 75 76 -- 1. Identical messages placed at the same point in the text. Such 77 -- duplicate error message result for example from rescanning 78 -- sections of the text that contain lexical errors. Only one of 79 -- such a set of duplicate messages is output, and the rest are 80 -- suppressed. 81 82 -- 2. If more than one parser message is generated for a single source 83 -- line, then only the first message is output, the remaining 84 -- messages on the same line are suppressed. 85 86 -- 3. If a message is posted on a node for which a message has been 87 -- previously posted, then only the first message is retained. The 88 -- Error_Posted flag is used to detect such multiple postings. Note 89 -- that this only applies to semantic messages, since otherwise 90 -- for parser messages, this would be a special case of case 2. 91 92 -- 4. If a message is posted on a node whose Etype or Entity 93 -- fields reference entities on which an error message has 94 -- already been placed, as indicated by the Error_Posted flag 95 -- being set on these entities, then the message is suppressed. 96 97 -- 5. If a message attempts to insert an Error node, or a direct 98 -- reference to the Any_Type node, then the message is suppressed. 99 100 -- 6. Note that cases 2-5 only apply to error messages, not warning 101 -- messages. Warning messages are only suppressed for case 1, and 102 -- when they come from other than the main extended unit. 103 104 -- This normal suppression action may be overridden in cases 2-5 (but 105 -- not in case 1) by setting All_Errors mode, or by setting the special 106 -- unconditional message insertion character (!) as described below. 107 108 --------------------------------------------------------- 109 -- Error Message Text and Message Insertion Characters -- 110 --------------------------------------------------------- 111 112 -- Error message text strings are composed of lower case letters, digits 113 -- and the special characters space, comma, period, colon and semicolon, 114 -- apostrophe and parentheses. Special insertion characters can also 115 -- appear which cause the error message circuit to modify the given 116 -- string as follows: 117 118 -- Insertion character % (Percent: insert name from Names table) 119 -- The character % is replaced by the text for the name specified by 120 -- the Name_Id value stored in Error_Msg_Name_1. A blank precedes the 121 -- name if it is preceded by a non-blank character other than left 122 -- parenthesis. The name is enclosed in quotes unless manual quotation 123 -- mode is set. If the Name_Id is set to No_Name, then no insertion 124 -- occurs; if the Name_Id is set to Error_Name, then the string 125 -- <error> is inserted. A second and third % may appear in a single 126 -- message, similarly replaced by the names which are specified by the 127 -- Name_Id values stored in Error_Msg_Name_2 and Error_Msg_Name_3. The 128 -- names are decoded and cased according to the current identifier 129 -- casing mode. Note: if a unit name ending with %b or %s is passed 130 -- for this kind of insertion, this suffix is simply stripped. Use a 131 -- unit name insertion ($) to process the suffix. 132 133 -- Insertion character %% (Double percent: insert literal name) 134 -- The character sequence %% acts as described above for %, except 135 -- that the name is simply obtained with Get_Name_String and is not 136 -- decoded or cased, it is inserted literally from the names table. 137 -- A trailing %b or %s is not treated specially. 138 139 -- Insertion character $ (Dollar: insert unit name from Names table) 140 -- The character $ is treated similarly to %, except that the name is 141 -- obtained from the Unit_Name_Type value in Error_Msg_Unit_1 and 142 -- Error_Msg_Unit_2, as provided by Get_Unit_Name_String in package 143 -- Uname. Note that this name includes the postfix (spec) or (body) 144 -- strings. If this postfix is not required, use the normal % 145 -- insertion for the unit name. 146 147 -- Insertion character { (Left brace: insert file name from names table) 148 -- The character { is treated similarly to %, except that the input 149 -- value is a File_Name_Type value stored in Error_Msg_File_1 or 150 -- Error_Msg_File_2 or Error_Msg_File_3. The value is output literally, 151 -- enclosed in quotes as for %, but the case is not modified, the 152 -- insertion is the exact string stored in the names table without 153 -- adjusting the casing. 154 155 -- Insertion character * (Asterisk, insert reserved word name) 156 -- The insertion character * is treated exactly like % except that the 157 -- resulting name is cased according to the default conventions for 158 -- reserved words (see package Scans). 159 160 -- Insertion character & (Ampersand: insert name from node) 161 -- The insertion character & is treated similarly to %, except that 162 -- the name is taken from the Chars field of the given node, and may 163 -- refer to a child unit name, or a selected component. The casing is, 164 -- if possible, taken from the original source reference, which is 165 -- obtained from the Sloc field of the given node or nodes. If no Sloc 166 -- is available (happens e.g. for nodes in package Standard), then the 167 -- default case (see Scans spec) is used. The nodes to be used are 168 -- stored in Error_Msg_Node_1, Error_Msg_Node_2. No insertion occurs 169 -- for the Empty node, and the Error node results in the insertion of 170 -- the characters <error>. In addition, if the special global variable 171 -- Error_Msg_Qual_Level is non-zero, then the reference will include 172 -- up to the given number of levels of qualification, using the scope 173 -- chain. 174 175 -- Insertion character # (Pound: insert line number reference) 176 -- The character # is replaced by the string indicating the source 177 -- position stored in Error_Msg_Sloc. There are three cases: 178 -- 179 -- for package Standard: in package Standard 180 -- for locations in current file: at line nnn:ccc 181 -- for locations in other files: at filename:nnn:ccc 182 -- 183 -- By convention, the # insertion character is only used at the end of 184 -- an error message, so the above strings only appear as the last 185 -- characters of an error message. The only exceptions to this rule 186 -- are that an RM reference may follow in the form (RM .....) and a 187 -- right parenthesis may immediately follow the #. In the case of 188 -- continued messages, # can only appear at the end of a group of 189 -- continuation messages, except that \\ messages which always start 190 -- a new line end the sequence from the point of view of this rule. 191 -- The idea is that for any use of -gnatj, it will still be the case 192 -- that a location reference appears only at the end of a line. 193 194 -- Note: the output of the string "at " is suppressed if the string 195 -- " from" or " from " immediately precedes the insertion character #. 196 -- Certain messages read better with from than at. 197 198 -- Insertion character } (Right brace: insert type reference) 199 -- The character } is replaced by a string describing the type 200 -- referenced by the entity whose Id is stored in Error_Msg_Node_1. 201 -- the string gives the name or description of the type, and also 202 -- where appropriate the location of its declaration. Special cases 203 -- like "some integer type" are handled appropriately. Only one } is 204 -- allowed in a message, since there is not enough room for two (the 205 -- insertion can be quite long, including a file name) In addition, if 206 -- the special global variable Error_Msg_Qual_Level is non-zero, then 207 -- the reference will include up to the given number of levels of 208 -- qualification, using the scope chain. 209 210 -- Insertion character @ (At: insert column number reference) 211 -- The character @ is replaced by null if the RM_Column_Check mode is 212 -- off (False). If the switch is on (True), then @ is replaced by the 213 -- text string " in column nnn" where nnn is the decimal 214 -- representation of the column number stored in Error_Msg_Col plus 215 -- one (the plus one is because the number is stored 0-origin and 216 -- displayed 1-origin). 217 218 -- Insertion character ^ (Caret: insert integer value) 219 -- The character ^ is replaced by the decimal conversion of the Uint 220 -- value stored in Error_Msg_Uint_1, with a possible leading minus. 221 -- A second ^ may occur in the message, in which case it is replaced 222 -- by the decimal conversion of the Uint value in Error_Msg_Uint_2. 223 224 -- Insertion character > (Greater Than, run time name) 225 -- The character > is replaced by a string of the form (name) if 226 -- Targparm scanned out a Run_Time_Name (see package Targparm for 227 -- details). The name is enclosed in parentheses and output in mixed 228 -- case mode (upper case after any space in the name). If no run time 229 -- name is defined, this insertion character has no effect. 230 231 -- Insertion character ! (Exclamation: unconditional message) 232 -- The character ! appearing anywhere in the text of a message makes 233 -- the message unconditional which means that it is output even if it 234 -- would normally be suppressed. See section above for a description 235 -- of the cases in which messages are normally suppressed. Note that 236 -- in the case of warnings, the meaning is that the warning should not 237 -- be removed in dead code (that's the only time that the use of ! 238 -- has any effect for a warning). 239 -- 240 -- Note: the presence of ! is ignored in continuation messages (i.e. 241 -- messages starting with the \ insertion character). The effect of the 242 -- use of ! in a parent message automatically applies to all of its 243 -- continuation messages (since we clearly don't want any case in which 244 -- continuations are separated from the main message). It is allowable 245 -- to put ! in continuation messages, and the usual style is to include 246 -- it, since it makes it clear that the continuation is part of an 247 -- unconditional message. 248 249 -- Insertion character !! (Double exclamation: unconditional warning) 250 -- Normally warning messages issued in other than the main unit are 251 -- suppressed. If the message contains !! then this suppression is 252 -- avoided. This is currently used by the Compile_Time_Warning pragma 253 -- to ensure the message for a with'ed unit is output, and for warnings 254 -- on ineffective back-end inlining, which is detected in units that 255 -- contain subprograms to be inlined in the main program. It is also 256 -- used by the Compiler_Unit_Warning pragma for similar reasons. 257 258 -- Insertion character ? (Question: warning message) 259 -- The character ? appearing anywhere in a message makes the message 260 -- warning instead of a normal error message, and the text of the 261 -- message will be preceded by "warning:" in the normal case. The 262 -- handling of warnings if further controlled by the Warning_Mode 263 -- option (-w switch), see package Opt for further details, and also by 264 -- the current setting from pragma Warnings. This pragma applies only 265 -- to warnings issued from the semantic phase (not the parser), but 266 -- currently all relevant warnings are posted by the semantic phase 267 -- anyway. Messages starting with (style) are also treated as warning 268 -- messages. 269 -- 270 -- Note: when a warning message is output, the text of the message is 271 -- preceded by "warning: " in the normal case. An exception to this 272 -- rule occurs when the text of the message starts with "info: " in 273 -- which case this string is not prepended. This allows callers to 274 -- label certain warnings as informational messages, rather than as 275 -- warning messages requiring some action. 276 -- 277 -- Note: the presence of ? is ignored in continuation messages (i.e. 278 -- messages starting with the \ insertion character). The warning 279 -- status of continuations is determined only by the parent message 280 -- which is being continued. It is allowable to put ? in continuation 281 -- messages, and the usual style is to include it, since it makes it 282 -- clear that the continuation is part of a warning message. 283 -- 284 -- Note: this usage is obsolete, use ??, ?x? or ?X? instead to specify 285 -- the string to be added when Warn_Doc_Switch is set to True. If this 286 -- switch is True, then for simple ? messages it has no effect. This 287 -- simple form is to ease transition and will be removed later. 288 289 -- Insertion character ?? (Two question marks: default warning) 290 -- Like ?, but if the flag Warn_Doc_Switch is True, adds the string 291 -- "[enabled by default]" at the end of the warning message. For 292 -- continuations, use this in each continuation message. 293 294 -- Insertion character ?x? (warning with switch) 295 -- Like ?, but if the flag Warn_Doc_Switch is True, adds the string 296 -- "[-gnatwx]" at the end of the warning message. x is a lower case 297 -- letter. For continuations, use this on each continuation message. 298 299 -- Insertion character ?X? (warning with dot switch) 300 -- Like ?, but if the flag Warn_Doc_Switch is True, adds the string 301 -- "[-gnatw.x]" at the end of the warning message. X is an upper case 302 -- letter corresponding to the lower case letter x in the message. 303 -- For continuations, use this on each continuation message. 304 305 -- Insertion character < (Less Than: conditional warning message) 306 -- The character < appearing anywhere in a message is used for a 307 -- conditional error message. If Error_Msg_Warn is True, then the 308 -- effect is the same as ? described above, and in particular << and 309 -- <X< have the effect of ?? and ?X? respectively. If Error_Msg_Warn 310 -- is False, then the < << or <X< sequence is ignored and the message 311 -- is treated as a error rather than a warning. 312 313 -- Insertion character A-Z (Upper case letter: Ada reserved word) 314 -- If two or more upper case letters appear in the message, they are 315 -- taken as an Ada reserved word, and are converted to the default 316 -- case for reserved words (see Scans package spec). Surrounding 317 -- quotes are added unless manual quotation mode is currently set. 318 -- RM and SPARK are special exceptions, they are never treated as 319 -- keywords, and just appear verbatim, with no surrounding quotes. 320 -- As a special case, 'R'M is used instead of RM (which is not treated 321 -- as a keyword) to indicate when the reference to the RM is possibly 322 -- not useful anymore, and could possibly be replaced by a comment 323 -- in the source. 324 325 -- Insertion character ` (Backquote: set manual quotation mode) 326 -- The backquote character always appears in pairs. Each backquote of 327 -- the pair is replaced by a double quote character. In addition, any 328 -- reserved keywords, or name insertions between these backquotes are 329 -- not surrounded by the usual automatic double quotes. See the 330 -- section below on manual quotation mode for further details. 331 332 -- Insertion character ' (Quote: literal character) 333 -- Precedes a character which is placed literally into the message. 334 -- Used to insert characters into messages that are one of the 335 -- insertion characters defined here. Also used for insertion of 336 -- upper case letter sequences not to be treated as keywords. 337 338 -- Insertion character \ (Backslash: continuation message) 339 -- Indicates that the message is a continuation of a message 340 -- previously posted. This is used to ensure that such groups of 341 -- messages are treated as a unit. The \ character must be the first 342 -- character of the message text. 343 344 -- Insertion character \\ (Two backslashes, continuation with new line) 345 -- This differs from \ only in -gnatjnn mode (Error_Message_Line_Length 346 -- set non-zero). This sequence forces a new line to start even when 347 -- continuations are being gathered into a single message. 348 349 -- Insertion character | (Vertical bar: non-serious error) 350 -- By default, error messages (other than warning messages) are 351 -- considered to be fatal error messages which prevent expansion or 352 -- generation of code in the presence of the -gnatQ switch. If the 353 -- insertion character | appears, the message is considered to be 354 -- non-serious, and does not cause Serious_Errors_Detected to be 355 -- incremented (so expansion is not prevented by such a msg). This 356 -- insertion character is ignored in continuation messages. 357 358 -- Insertion character ~ (Tilde: insert string) 359 -- Indicates that Error_Msg_String (1 .. Error_Msg_Strlen) is to be 360 -- inserted to replace the ~ character. The string is inserted in the 361 -- literal form it appears, without any action on special characters. 362 363 -- Insertion character [ (Left bracket: will/would be raised at run time) 364 -- This is used in messages about exceptions being raised at run-time. 365 -- If the current message is a warning message, then if the code is 366 -- executed, the exception will be raised, and [ inserts: 367 -- 368 -- will be raised at run time 369 -- 370 -- If the current message is an error message, then it is an error 371 -- because the exception would have been raised and [ inserts: 372 -- 373 -- would have been raised at run time 374 -- 375 -- Typically the message contains a < insertion which means that the 376 -- message is a warning or error depending on Error_Msg_Warn. This is 377 -- most typically used in the context of messages which are normally 378 -- warnings, but are errors in GNATprove mode, corresponding to the 379 -- permission in the definition of SPARK that allows an implementation 380 -- to reject a program as illegal if a situation arises in which the 381 -- compiler can determine that it is certain that a run-time check 382 -- would have fail if the statement was executed. 383 384 -- Insertion character ] (Right bracket: may/might be raised at run time) 385 -- This is like [ except that the insertion messages say may/might, 386 -- instead of will/would. 387 388 ---------------------------------------- 389 -- Specialization of Messages for VMS -- 390 ---------------------------------------- 391 392 -- Some messages mention gcc-style switch names. When using an OpenVMS 393 -- host, such switch names must be converted to their corresponding VMS 394 -- qualifer. The following table controls this translation. In each case 395 -- the original message must contain the string "-xxx switch", where xxx 396 -- is the Gname? entry from below, and this string will be replaced by 397 -- "/yyy qualifier", where yyy is the corresponding Vname? entry. 398 399 Gname1 : aliased constant String := "fno-strict-aliasing"; 400 Vname1 : aliased constant String := "OPTIMIZE=NO_STRICT_ALIASING"; 401 402 Gname2 : aliased constant String := "gnatX"; 403 Vname2 : aliased constant String := "EXTENSIONS_ALLOWED"; 404 405 Gname3 : aliased constant String := "gnatW"; 406 Vname3 : aliased constant String := "WIDE_CHARACTER_ENCODING"; 407 408 Gname4 : aliased constant String := "gnatf"; 409 Vname4 : aliased constant String := "REPORT_ERRORS=FULL"; 410 411 Gname5 : aliased constant String := "gnat05"; 412 Vname5 : aliased constant String := "05"; 413 414 Gname6 : aliased constant String := "gnat2005"; 415 Vname6 : aliased constant String := "2005"; 416 417 Gname7 : aliased constant String := "gnat12"; 418 Vname7 : aliased constant String := "12"; 419 420 Gname8 : aliased constant String := "gnat2012"; 421 Vname8 : aliased constant String := "2012"; 422 423 Gname9 : aliased constant String := "gnateinn"; 424 Vname9 : aliased constant String := "MAX_INSTANTIATIONS=nn"; 425 426 type Cstring_Ptr is access constant String; 427 428 Gnames : array (Nat range <>) of Cstring_Ptr := 429 (Gname1'Access, 430 Gname2'Access, 431 Gname3'Access, 432 Gname4'Access, 433 Gname5'Access, 434 Gname6'Access, 435 Gname7'Access, 436 Gname8'Access, 437 Gname9'Access); 438 439 Vnames : array (Nat range <>) of Cstring_Ptr := 440 (Vname1'Access, 441 Vname2'Access, 442 Vname3'Access, 443 Vname4'Access, 444 Vname5'Access, 445 Vname6'Access, 446 Vname7'Access, 447 Vname8'Access, 448 Vname9'Access); 449 450 ----------------------------------------------------- 451 -- Global Values Used for Error Message Insertions -- 452 ----------------------------------------------------- 453 454 -- The following global variables are essentially additional parameters 455 -- passed to the error message routine for insertion sequences described 456 -- above. The reason these are passed globally is that the insertion 457 -- mechanism is essentially an untyped one in which the appropriate 458 -- variables are set depending on the specific insertion characters used. 459 460 -- Note that is mandatory that the caller ensure that global variables 461 -- are set before the Error_Msg call, otherwise the result is undefined. 462 463 Error_Msg_Col : Column_Number renames Err_Vars.Error_Msg_Col; 464 -- Column for @ insertion character in message 465 466 Error_Msg_Uint_1 : Uint renames Err_Vars.Error_Msg_Uint_1; 467 Error_Msg_Uint_2 : Uint renames Err_Vars.Error_Msg_Uint_2; 468 -- Uint values for ^ insertion characters in message 469 470 Error_Msg_Sloc : Source_Ptr renames Err_Vars.Error_Msg_Sloc; 471 -- Source location for # insertion character in message 472 473 Error_Msg_Name_1 : Name_Id renames Err_Vars.Error_Msg_Name_1; 474 Error_Msg_Name_2 : Name_Id renames Err_Vars.Error_Msg_Name_2; 475 Error_Msg_Name_3 : Name_Id renames Err_Vars.Error_Msg_Name_3; 476 -- Name_Id values for % insertion characters in message 477 478 Error_Msg_File_1 : File_Name_Type renames Err_Vars.Error_Msg_File_1; 479 Error_Msg_File_2 : File_Name_Type renames Err_Vars.Error_Msg_File_2; 480 Error_Msg_File_3 : File_Name_Type renames Err_Vars.Error_Msg_File_3; 481 -- File_Name_Type values for { insertion characters in message 482 483 Error_Msg_Unit_1 : Unit_Name_Type renames Err_Vars.Error_Msg_Unit_1; 484 Error_Msg_Unit_2 : Unit_Name_Type renames Err_Vars.Error_Msg_Unit_2; 485 -- Unit_Name_Type values for $ insertion characters in message 486 487 Error_Msg_Node_1 : Node_Id renames Err_Vars.Error_Msg_Node_1; 488 Error_Msg_Node_2 : Node_Id renames Err_Vars.Error_Msg_Node_2; 489 -- Node_Id values for & insertion characters in message 490 491 Error_Msg_Qual_Level : Int renames Err_Vars.Error_Msg_Qual_Level; 492 -- Number of levels of qualification required for type name (see the 493 -- description of the } insertion character). Note that this value does 494 -- note get reset by any Error_Msg call, so the caller is responsible 495 -- for resetting it. 496 497 Error_Msg_Warn : Boolean renames Err_Vars.Error_Msg_Warn; 498 -- Used if current message contains a < insertion character to indicate 499 -- if the current message is a warning message. Must be set appropriately 500 -- before any call to Error_Msg_xxx with a < insertion character present. 501 -- Setting is irrelevant if no < insertion character is present. 502 503 Error_Msg_String : String renames Err_Vars.Error_Msg_String; 504 Error_Msg_Strlen : Natural renames Err_Vars.Error_Msg_Strlen; 505 -- Used if current message contains a ~ insertion character to indicate 506 -- insertion of the string Error_Msg_String (1 .. Error_Msg_Strlen). 507 508 ----------------------------------------------------- 509 -- Format of Messages and Manual Quotation Control -- 510 ----------------------------------------------------- 511 512 -- Messages are generally all in lower case, except for inserted names 513 -- and appear in one of the following three forms: 514 515 -- error: text 516 -- warning: text 517 518 -- The prefixes error and warning are supplied automatically (depending 519 -- on the use of the ? insertion character), and the call to the error 520 -- message routine supplies the text. The "error: " prefix is omitted 521 -- in brief error message formats. 522 523 -- Reserved Ada keywords in the message are in the default keyword case 524 -- (determined from the given source program), surrounded by quotation 525 -- marks. This is achieved by spelling the reserved word in upper case 526 -- letters, which is recognized as a request for insertion of quotation 527 -- marks by the error text processor. Thus for example: 528 529 -- Error_Msg_AP ("IS expected"); 530 531 -- would result in the output of one of the following: 532 533 -- error: "is" expected 534 -- error: "IS" expected 535 -- error: "Is" expected 536 537 -- the choice between these being made by looking at the casing convention 538 -- used for keywords (actually the first compilation unit keyword) in the 539 -- source file. 540 541 -- Note: a special exception is that RM is never treated as a keyword 542 -- but instead is copied literally into the message, this avoids the 543 -- need for writing 'R'M for all reference manual quotes. A similar 544 -- exception is applied to the occurrence of the string SPARK used in 545 -- error messages about the SPARK subset of Ada. 546 547 -- In the case of names, the default mode for the error text processor 548 -- is to surround the name by quotation marks automatically. The case 549 -- used for the identifier names is taken from the source program where 550 -- possible, and otherwise is the default casing convention taken from 551 -- the source file usage. 552 553 -- In some cases, better control over the placement of quote marks is 554 -- required. This is achieved using manual quotation mode. In this mode, 555 -- one or more insertion sequences is surrounded by backquote characters. 556 -- The backquote characters are output as double quote marks, and normal 557 -- automatic insertion of quotes is suppressed between the double quotes. 558 -- For example: 559 560 -- Error_Msg_AP ("`END &;` expected"); 561 562 -- generates a message like 563 564 -- error: "end Open_Scope;" expected 565 566 -- where the node specifying the name Open_Scope has been stored in 567 -- Error_Msg_Node_1 prior to the call. The great majority of error 568 -- messages operates in normal quotation mode. 569 570 -- Note: the normal automatic insertion of spaces before insertion 571 -- sequences (such as those that come from & and %) is suppressed in 572 -- manual quotation mode, so blanks, if needed as in the above example, 573 -- must be explicitly present. 574 575 ---------------------------- 576 -- Message ID Definitions -- 577 ---------------------------- 578 579 subtype Error_Msg_Id is Erroutc.Error_Msg_Id; 580 function "=" (Left, Right : Error_Msg_Id) return Boolean 581 renames Erroutc."="; 582 -- A type used to represent specific error messages. Used by the clients 583 -- of this package only in the context of the Get_Error_Id and 584 -- Change_Error_Text subprograms. 585 586 No_Error_Msg : constant Error_Msg_Id := Erroutc.No_Error_Msg; 587 -- A constant which is different from any value returned by Get_Error_Id. 588 -- Typically used by a client to indicate absense of a saved Id value. 589 590 function Get_Msg_Id return Error_Msg_Id renames Erroutc.Get_Msg_Id; 591 -- Returns the Id of the message most recently posted using one of the 592 -- Error_Msg routines. 593 594 function Get_Location (E : Error_Msg_Id) return Source_Ptr 595 renames Erroutc.Get_Location; 596 -- Returns the flag location of the error message with the given id E 597 598 ------------------------ 599 -- List Pragmas Table -- 600 ------------------------ 601 602 -- When a pragma Page or pragma List is encountered by the parser, an 603 -- entry is made in the following table. This table is then used to 604 -- control the full listing if one is being generated. Note that the 605 -- reason we do the processing in the parser is so that we get proper 606 -- listing control even in syntax check only mode. 607 608 type List_Pragma_Type is (List_On, List_Off, Page); 609 610 type List_Pragma_Record is record 611 Ptyp : List_Pragma_Type; 612 Ploc : Source_Ptr; 613 end record; 614 615 -- Note: Ploc points to the terminating semicolon in the List_Off and Page 616 -- cases, and to the pragma keyword for List_On. In the case of a pragma 617 -- List_Off, a List_On entry is also made in the table, pointing to the 618 -- pragma keyword. This ensures that, as required, a List (Off) pragma is 619 -- listed even in list off mode. 620 621 package List_Pragmas is new Table.Table ( 622 Table_Component_Type => List_Pragma_Record, 623 Table_Index_Type => Int, 624 Table_Low_Bound => 1, 625 Table_Initial => 50, 626 Table_Increment => 200, 627 Table_Name => "List_Pragmas"); 628 629 --------------------------- 630 -- Ignore_Errors Feature -- 631 --------------------------- 632 633 -- In certain cases, notably for optional subunits, the compiler operates 634 -- in a mode where errors are to be ignored, and the whole unit is to be 635 -- considered as not present. To implement this we provide the following 636 -- flag to enable special handling, where error messages are suppressed, 637 -- but the Fatal_Error flag will still be set in the normal manner. 638 639 Ignore_Errors_Enable : Nat := 0; 640 -- Triggering switch. If non-zero, then ignore errors mode is activated. 641 -- This is a counter to allow convenient nesting of enable/disable. 642 643 ----------------------- 644 -- CODEFIX Facility -- 645 ----------------------- 646 647 -- The GPS and GNATBench IDE's have a codefix facility that allows for 648 -- automatic correction of a subset of the errors and warnings issued 649 -- by the compiler. This is done by recognizing the text of specific 650 -- messages using appropriate matching patterns. 651 652 -- The text of such messages should not be altered without coordinating 653 -- with the codefix code. All such messages are marked by a specific 654 -- style of comments, as shown by the following example: 655 656 -- Error_Msg_N -- CODEFIX 657 -- (parameters ....) 658 659 -- Any message marked with this -- CODEFIX comment should not be modified 660 -- without appropriate coordination. 661 662 ------------------------------ 663 -- Error Output Subprograms -- 664 ------------------------------ 665 666 procedure Initialize; 667 -- Initializes for output of error messages. Must be called for each 668 -- source file before using any of the other routines in the package. 669 670 procedure Finalize (Last_Call : Boolean); 671 -- Finalize processing of error message list. Includes processing for 672 -- duplicated error messages, and other similar final adjustment of the 673 -- list of error messages. Note that this procedure must be called before 674 -- calling Compilation_Errors to determine if there were any errors. It 675 -- is perfectly fine to call Finalize more than once, providing that the 676 -- parameter Last_Call is set False for every call except the last call. 677 678 -- This multiple call capability is used to do some processing that may 679 -- generate messages. Call Finalize to eliminate duplicates and remove 680 -- deleted warnings. Test for compilation errors using Compilation_Errors, 681 -- then generate some more errors/warnings, call Finalize again to make 682 -- sure that all duplicates in these new messages are dealt with, then 683 -- finally call Output_Messages to output the final list of messages. The 684 -- argument Last_Call must be set False on all calls except the last call, 685 -- and must be set True on the last call (a value of True activates some 686 -- processing that must only be done after all messages are posted). 687 688 procedure Output_Messages; 689 -- Output list of messages, including messages giving number of detected 690 -- errors and warnings. 691 692 procedure Error_Msg (Msg : String; Flag_Location : Source_Ptr); 693 -- Output a message at specified location. Can be called from the parser 694 -- or the semantic analyzer. 695 696 procedure Error_Msg_S (Msg : String); 697 -- Output a message at current scan pointer location. This routine can be 698 -- called only from the parser, since it references Scan_Ptr. 699 700 procedure Error_Msg_AP (Msg : String); 701 -- Output a message just after the previous token. This routine can be 702 -- called only from the parser, since it references Prev_Token_Ptr. 703 704 procedure Error_Msg_BC (Msg : String); 705 -- Output a message just before the current token. Note that the important 706 -- difference between this and the previous routine is that the BC case 707 -- posts a flag on the current line, whereas AP can post a flag at the 708 -- end of the preceding line. This routine can be called only from the 709 -- parser, since it references Token_Ptr. 710 711 procedure Error_Msg_SC (Msg : String); 712 -- Output a message at the start of the current token, unless we are at 713 -- the end of file, in which case we always output the message after the 714 -- last real token in the file. This routine can be called only from the 715 -- parser, since it references Token_Ptr. 716 717 procedure Error_Msg_SP (Msg : String); 718 -- Output a message at the start of the previous token. This routine can 719 -- be called only from the parser, since it references Prev_Token_Ptr. 720 721 procedure Error_Msg_N (Msg : String; N : Node_Or_Entity_Id); 722 -- Output a message at the Sloc of the given node. This routine can be 723 -- called from the parser or the semantic analyzer, although the call from 724 -- the latter is much more common (and is the most usual way of generating 725 -- error messages from the analyzer). The message text may contain a 726 -- single & insertion, which will reference the given node. The message is 727 -- suppressed if the node N already has a message posted, or if it is a 728 -- warning and N is an entity node for which warnings are suppressed. 729 730 procedure Error_Msg_F (Msg : String; N : Node_Id); 731 -- Similar to Error_Msg_N except that the message is placed on the first 732 -- node of the construct N (First_Node (N)). Note that this procedure uses 733 -- Original_Node to look at the original source tree, since that's what we 734 -- want for placing an error message flag in the right place. 735 736 procedure Error_Msg_NE 737 (Msg : String; 738 N : Node_Or_Entity_Id; 739 E : Node_Or_Entity_Id); 740 -- Output a message at the Sloc of the given node N, with an insertion of 741 -- the name from the given entity node E. This is used by the semantic 742 -- routines, where this is a common error message situation. The Msg text 743 -- will contain a & or } as usual to mark the insertion point. This 744 -- routine can be called from the parser or the analyzer. 745 746 procedure Error_Msg_FE 747 (Msg : String; 748 N : Node_Id; 749 E : Node_Or_Entity_Id); 750 -- Same as Error_Msg_NE, except that the message is placed on the first 751 -- node of the construct N (First_Node (N)). 752 753 procedure Error_Msg_NEL 754 (Msg : String; 755 N : Node_Or_Entity_Id; 756 E : Node_Or_Entity_Id; 757 Flag_Location : Source_Ptr); 758 -- Exactly the same as Error_Msg_NE, except that the flag is placed at 759 -- the specified Flag_Location instead of at Sloc (N). 760 761 procedure Error_Msg_NW 762 (Eflag : Boolean; 763 Msg : String; 764 N : Node_Or_Entity_Id); 765 -- This routine is used for posting a message conditionally. The message 766 -- is posted (with the same effect as Error_Msg_N (Msg, N) if and only 767 -- if Eflag is True and if the node N is within the main extended source 768 -- unit and comes from source. Typically this is a warning mode flag. 769 -- This routine can only be called during semantic analysis. It may not 770 -- be called during parsing. 771 772 procedure Change_Error_Text (Error_Id : Error_Msg_Id; New_Msg : String); 773 -- The error message text of the message identified by Id is replaced by 774 -- the given text. This text may contain insertion characters in the 775 -- usual manner, and need not be the same length as the original text. 776 777 function First_Node (C : Node_Id) return Node_Id; 778 -- Given a construct C, finds the first node in the construct, i.e. the one 779 -- with the lowest Sloc value. This is useful in placing error msgs. Note 780 -- that this procedure uses Original_Node to look at the original source 781 -- tree, since that's what we want for placing an error message flag in 782 -- the right place. 783 784 function First_Sloc (N : Node_Id) return Source_Ptr; 785 -- Given the node for an expression, return a source pointer value that 786 -- points to the start of the first token in the expression. In the case 787 -- where the expression is parenthesized, an attempt is made to include 788 -- the parentheses (i.e. to return the location of the initial paren). 789 790 function Get_Ignore_Errors return Boolean; 791 -- Return True if all error calls are ignored. 792 793 procedure Purge_Messages (From : Source_Ptr; To : Source_Ptr) 794 renames Erroutc.Purge_Messages; 795 -- All error messages whose location is in the range From .. To (not 796 -- including the end points) will be deleted from the error listing. 797 798 procedure Remove_Warning_Messages (N : Node_Id); 799 -- Remove any warning messages corresponding to the Sloc of N or any 800 -- of its descendent nodes. No effect if no such warnings. Note that 801 -- style messages (identified by the fact that they start with "(style)" 802 -- are not removed by this call. Basically the idea behind this procedure 803 -- is to remove warnings about execution conditions from known dead code. 804 805 procedure Remove_Warning_Messages (L : List_Id); 806 -- Remove warnings on all elements of a list (Calls Remove_Warning_Messages 807 -- on each element of the list, see above). 808 809 procedure Set_Ignore_Errors (To : Boolean); 810 -- Following a call to this procedure with To=True, all error calls are 811 -- ignored. A call with To=False restores the default treatment in which 812 -- error calls are treated as usual (and as described in this spec). 813 814 procedure Set_Warnings_Mode_Off (Loc : Source_Ptr; Reason : String_Id) 815 renames Erroutc.Set_Warnings_Mode_Off; 816 -- Called in response to a pragma Warnings (Off) to record the source 817 -- location from which warnings are to be turned off. Reason is the 818 -- Reason from the pragma, or the null string if none is given. 819 820 procedure Set_Warnings_Mode_On (Loc : Source_Ptr) 821 renames Erroutc.Set_Warnings_Mode_On; 822 -- Called in response to a pragma Warnings (On) to record the source 823 -- location from which warnings are to be turned back on. 824 825 procedure Set_Specific_Warning_Off 826 (Loc : Source_Ptr; 827 Msg : String; 828 Reason : String_Id; 829 Config : Boolean; 830 Used : Boolean := False) 831 renames Erroutc.Set_Specific_Warning_Off; 832 -- This is called in response to the two argument form of pragma Warnings 833 -- where the first argument is OFF, and the second argument is a string 834 -- which identifies a specific warning to be suppressed. The first argument 835 -- is the start of the suppression range, and the second argument is the 836 -- string from the pragma. Loc is the location of the pragma (which is the 837 -- start of the range to suppress). Reason is the reason string from the 838 -- pragma, or the null string if no reason is given. Config is True for the 839 -- configuration pragma case (where there is no requirement for a matching 840 -- OFF pragma). Used is set True to disable the check that the warning 841 -- actually has has the effect of suppressing a warning. 842 843 procedure Set_Specific_Warning_On 844 (Loc : Source_Ptr; 845 Msg : String; 846 Err : out Boolean) 847 renames Erroutc.Set_Specific_Warning_On; 848 -- This is called in response to the two argument form of pragma Warnings 849 -- where the first argument is ON, and the second argument is the prefix 850 -- of a specific warning to be suppressed. The first argument is the end 851 -- of the suppression range, and the second argument is the string from 852 -- the pragma. Err is set to True on return to report the error of no 853 -- matching Warnings Off pragma preceding this one. 854 855 function Compilation_Errors return Boolean; 856 -- Returns True if errors have been detected, or warnings in -gnatwe (treat 857 -- warnings as errors) mode. Note that it is mandatory to call Finalize 858 -- before calling this routine. Always returns False in formal verification 859 -- mode, because errors issued when analyzing code are not compilation 860 -- errors, and should not result in exiting with an error status. 861 862 procedure Error_Msg_CRT (Feature : String; N : Node_Id); 863 -- Posts a non-fatal message on node N saying that the feature identified 864 -- by the Feature argument is not supported in either configurable 865 -- run-time mode or no run-time mode (as appropriate). In the former case, 866 -- the name of the library is output if available. 867 868 procedure Error_Msg_PT (Typ : Node_Id; Subp : Node_Id); 869 -- Posts an error on the protected type declaration Typ indicating wrong 870 -- mode of the first formal of protected type primitive Subp. 871 872 procedure Error_Msg_Ada_2012_Feature (Feature : String; Loc : Source_Ptr); 873 -- If not operating in Ada 2012 mode, posts errors complaining that Feature 874 -- is only supported in Ada 2012, with appropriate suggestions to fix this. 875 -- Loc is the location at which the flag is to be posted. Feature, which 876 -- appears at the start of the first generated message, may contain error 877 -- message insertion characters in the normal manner, and in particular 878 -- may start with | to flag a non-serious error. 879 880 procedure dmsg (Id : Error_Msg_Id) renames Erroutc.dmsg; 881 -- Debugging routine to dump an error message 882 883 ------------------------------------ 884 -- Utility Interface for Back End -- 885 ------------------------------------ 886 887 -- The following subprograms can be used by the back end for the purposes 888 -- of concocting error messages that are not output via Errout, e.g. the 889 -- messages generated by the gcc back end. 890 891 procedure Set_Identifier_Casing 892 (Identifier_Name : System.Address; 893 File_Name : System.Address); 894 -- The identifier is a null terminated string that represents the name of 895 -- an identifier appearing in the source program. File_Name is a null 896 -- terminated string giving the corresponding file name for the identifier 897 -- as obtained from the front end by the use of Full_Debug_Name to the 898 -- source file referenced by the corresponding source location value. On 899 -- return, the name is in Name_Buffer, null terminated with Name_Len set. 900 -- This name is the identifier name as passed, cased according to the 901 -- default identifier casing for the given file. 902 903end Errout; 904