1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- L I B . W R I T -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2003 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 2, 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 COPYING. If not, write -- 19-- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- 20-- MA 02111-1307, USA. -- 21-- -- 22-- GNAT was originally developed by the GNAT team at New York University. -- 23-- Extensive contributions were provided by Ada Core Technologies Inc. -- 24-- -- 25------------------------------------------------------------------------------ 26 27-- This package contains the routines for writing the library information 28 29package Lib.Writ is 30 31 ----------------------------------- 32 -- Format of Library Information -- 33 ----------------------------------- 34 35 -- Note: the contents of the ali file are summarized in the GNAT 36 -- user's guide, so if any non-trivial changes are made to this 37 -- section, they should be reflected in the user's guide. 38 39 -- This section describes the format of the library information that is 40 -- associated with object files. The exact method of this association is 41 -- potentially implementation dependent and is described and implemented 42 -- in package ali. From the point of view of the description here, all we 43 -- need to know is that the information is represented as a string of 44 -- characters that is somehow associated with an object file, and can be 45 -- retrieved. If no library information exists for a given object file, 46 -- then we take this as equivalent to the non-existence of the object 47 -- file, as if source file has not been previously compiled. 48 49 -- The library information is written as a series of lines of the form: 50 51 -- Key_Character parameter parameter ... 52 53 ------------------ 54 -- Header Lines -- 55 ------------------ 56 57 -- The initial header lines in the file give information about the 58 -- compilation environment, and identify other special information 59 -- such as main program parameters. 60 61 -- ---------------- 62 -- -- V Version -- 63 -- ---------------- 64 65 -- V "xxxxxxxxxxxxxxxx" 66 -- 67 -- This line indicates the library output version, as defined in 68 -- Gnatvsn. It ensures that separate object modules of a program are 69 -- consistent. It has to be changed if anything changes which would 70 -- affect successful binding of separately compiled modules. 71 -- Examples of such changes are modifications in the format of the 72 -- library info described in this package, or modifications to 73 -- calling sequences, or to the way that data is represented. 74 75 -- --------------------- 76 -- -- M Main Program -- 77 -- --------------------- 78 79 -- M type [priority] [T=time-slice] W=? 80 81 -- This line appears only if the main unit for this file is 82 -- suitable for use as a main program. The parameters are: 83 84 -- type 85 86 -- P for a parameterless procedure 87 -- F for a function returning a value of integral type 88 -- (used for writing a main program returning an exit status) 89 90 -- priority 91 92 -- Present only if there was a valid pragma Priority in the 93 -- corresponding unit to set the main task priority. It is 94 -- an unsigned decimal integer. 95 96 -- T=time-slice 97 98 -- Present only if there was a valid pragma Time_Slice in the 99 -- corresponding unit. It is an unsigned decimal integer in 100 -- the range 0 .. 10**9 giving the time slice value in units 101 -- of milliseconds. The actual significance of this parameter 102 -- is target dependent. 103 104 -- W=? 105 106 -- This parameter indicates the wide character encoding 107 -- method used when compiling the main program file. The ? 108 -- character is the single character used in the -gnatW? 109 -- switch. This is used to provide the default wide-character 110 -- encoding for Wide_Text_IO files. 111 112 -- ----------------- 113 -- -- A Argument -- 114 -- ----------------- 115 116 -- A argument 117 118 -- One of these lines appears for each of the arguments present 119 -- in the call to the gnat1 program. This can be used if it is 120 -- necessary to reconstruct this call (e.g. for fix and continue) 121 122 -- ------------------- 123 -- -- P Parameters -- 124 -- ------------------- 125 126 -- P <<parameters>> 127 128 -- Indicates various information that applies to the compilation 129 -- of the corresponding source unit. Parameters is a sequence of 130 -- zero or more two letter codes that indicate configuration 131 -- pragmas and other parameters that apply: 132 -- 133 -- The arguments are as follows: 134 -- 135 -- CE Compilation errors. If this is present it means that the 136 -- ali file resulted from a compilation with the -gnatQ 137 -- switch set, and illegalities were detected. The ali 138 -- file contents may not be completely reliable, but the 139 -- format will be correct and complete. Note that NO is 140 -- always present if CE is present. 141 -- 142 -- FD Configuration pragmas apply to all the units in this 143 -- file specifying a possibly non-standard floating point 144 -- format (VAX float with Long_Float using D_Float) 145 -- 146 -- FG Configuration pragmas apply to all the units in this 147 -- file specifying a possibly non-standard floating point 148 -- format (VAX float with Long_Float using G_Float) 149 -- 150 -- FI Configuration pragmas apply to all the units in this 151 -- file specifying a possibly non-standard floating point 152 -- format (IEEE Float) 153 -- 154 -- Lx A valid Locking_Policy pragma applies to all the units 155 -- in this file, where x is the first character (upper case) 156 -- of the policy name (e.g. 'C' for Ceiling_Locking) 157 -- 158 -- NO No object. This flag indicates that the units in this 159 -- file were not compiled to produce an object. This can 160 -- occur as a result of the use of -gnatc, or if no object 161 -- can be produced (e.g. when a package spec is compiled 162 -- instead of the body, or a subunit on its own). 163 -- 164 -- NR No_Run_Time. Indicates that a pragma No_Run_Time applies 165 -- to all units in the file. 166 -- 167 -- NS Normalize_Scalars pragma in effect for all units in 168 -- this file 169 -- 170 -- Qx A valid Queueing_Policy pragma applies to all the units 171 -- in this file, where x is the first character (upper case) 172 -- of the policy name (e.g. 'P' for Priority_Queueing). 173 -- 174 -- SL Indicates that the unit is an Interface to a Standalone 175 -- Library. Note that this indication is never given by the 176 -- compiler, but is added by the Project Manager in gnatmake 177 -- when an Interface ALI file is copied to the library 178 -- directory. 179 180 -- SS This unit references System.Secondary_Stack (that is, 181 -- the unit makes use of the secondary stack facilities). 182 -- 183 -- Tx A valid Task_Dispatching_Policy pragma applies to all 184 -- the units in this file, where x is the first character 185 -- (upper case) of the corresponding policy name (e.g. 'F' 186 -- for FIFO_Within_Priorities). 187 -- 188 -- UA Unreserve_All_Interrupts pragma was processed in one or 189 -- more units in this file 190 -- 191 -- UX Generated code contains unit exception table pointer 192 -- (i.e. it uses zero-cost exceptions, and there is at 193 -- least one subprogram present). 194 -- 195 -- ZX Units in this file use zero-cost exceptions and have 196 -- generated exception tables. If ZX is not present, the 197 -- longjmp/setjmp exception scheme is in use. 198 -- 199 -- Note that language defined units never output policy (Lx,Tx,Qx) 200 -- parameters. Language defined units must correctly handle all 201 -- possible cases. These values are checked for consistency by the 202 -- binder and then copied to the generated binder output file. 203 204 -- --------------------- 205 -- -- R Restrictions -- 206 -- --------------------- 207 208 -- R <<restriction-characters>> 209 210 -- This line records information regarding restrictions. The 211 -- parameter is a string of characters, one for each entry in 212 -- Restrict.Compilation_Unit_Restrictions, in order. There are 213 -- three settings possible settings for each restriction: 214 215 -- r Restricted. Unit was compiled under control of a pragma 216 -- Restrictions for the corresponding restriction. In 217 -- this case the unit certainly does not violate the 218 -- Restriction, since this would have been detected by 219 -- the compiler. 220 221 -- n Not used. The unit was not compiled under control of a 222 -- pragma Restrictions for the corresponding restriction, 223 -- and does not make any use of the referenced feature. 224 225 -- v Violated. The unit was not compiled under control of a 226 -- pragma Restrictions for the corresponding restriction, 227 -- and it does indeed use the referenced feature. 228 229 -- This information is used in the binder to check consistency, 230 -- i.e. to detect cases where one unit has "r" and another unit 231 -- has "v", which is not permitted, since these restrictions 232 -- are partition-wide. 233 234 -- ------------------------ 235 -- -- I Interrupt States -- 236 -- ------------------------ 237 238 -- I interrupt-number interrupt-state line-number 239 240 -- This line records information from an Interrupt_State pragma. 241 -- There is one line for each separate pragma, and if no such 242 -- pragmas are used, then no I lines are present. 243 244 -- The interrupt-number is an unsigned positive integer giving 245 -- the value of the interrupt as defined in Ada.Interrupts.Names. 246 247 -- The interrupt-state is one of r/s/u for Runtime/System/User 248 249 -- The line number is an unsigned decimal integer giving the 250 -- line number of the corresponding Interrupt_State pragma. 251 -- This is used in consistency messages. 252 253 ---------------------------- 254 -- Compilation Unit Lines -- 255 ---------------------------- 256 257 -- Following these header lines, a set of information lines appears for 258 -- each compilation unit that appears in the corresponding object file. 259 -- In particular, when a package body or subprogram body is compiled, 260 -- there will be two sets of information, one for the spec and one for 261 -- the body. with the entry for the body appearing first. This is the 262 -- only case in which a single ALI file contains more than one unit (in 263 -- particular note that subunits do *not* count as compilation units for 264 -- this purpose, and generate no library information, since they are 265 -- inlined). 266 267 -- -------------------- 268 -- -- U Unit Header -- 269 -- -------------------- 270 271 -- The lines for each compilation unit have the following form. 272 273 -- U unit-name source-name version <<attributes>> 274 -- 275 -- This line identifies the unit to which this section of the 276 -- library information file applies. The first three parameters are 277 -- the unit name in internal format, as described in package Uname, 278 -- and the name of the source file containing the unit. 279 -- 280 -- Version is the version given as eight hexadecimal characters 281 -- with upper case letters. This value is the exclusive or of the 282 -- source checksums of the unit and all its semantically dependent 283 -- units. 284 -- 285 -- The <<attributes>> are a series of two letter codes indicating 286 -- information about the unit: 287 -- 288 -- DE Dynamic Elaboration. This unit was compiled with the 289 -- dynamic elaboration model, as set by either the -gnatE 290 -- switch or pragma Elaboration_Checks (Dynamic). 291 -- 292 -- EB Unit has pragma Elaborate_Body 293 -- 294 -- EE Elaboration entity is present which must be set true when 295 -- the unit is elaborated. The name of the elaboration entity 296 -- is formed from the unit name in the usual way. If EE is 297 -- present, then this boolean must be set True as part of the 298 -- elaboration processing routine generated by the binder. 299 -- Note that EE can be set even if NE is set. This happens 300 -- when the boolean is needed solely for checking for the 301 -- case of access before elaboration. 302 -- 303 -- GE Unit is a generic declaration, or corresponding body 304 -- 305 -- IL Unit source uses a style with identifiers in all lower 306 -- IU case (IL) or all upper case (IU). If the standard mixed- 307 -- case usage is detected, or the compiler cannot determine 308 -- the style, then no I parameter will appear. 309 -- 310 -- IS Initialize_Scalars pragma applies to this unit 311 -- 312 -- KM Unit source uses a style with keywords in mixed case 313 -- KU (KM) or all upper case (KU). If the standard lower-case 314 -- usage is detected, or the compiler cannot determine the 315 -- style, then no K parameter will appear. 316 -- 317 -- NE Unit has no elaboration routine. All subprogram bodies 318 -- and specs are in this category. Package bodies and specs 319 -- may or may not have NE set, depending on whether or not 320 -- elaboration code is required. Set if N_Compilation_Unit 321 -- node has flag Has_No_Elaboration_Code set. 322 -- 323 -- PK Unit is package, rather than a subprogram 324 -- 325 -- PU Unit has pragma Pure 326 -- 327 -- PR Unit has pragma Preelaborate 328 -- 329 -- RA Unit declares a Remote Access to Class-Wide (RACW) type 330 -- 331 -- RC Unit has pragma Remote_Call_Interface 332 -- 333 -- RT Unit has pragma Remote_Types 334 -- 335 -- SP Unit has pragma Shared_Passive. 336 -- 337 -- SU Unit is a subprogram, rather than a package 338 -- 339 -- The attributes may appear in any order, separated by spaces. 340 341 -- --------------------- 342 -- -- W Withed Units -- 343 -- --------------------- 344 345 -- Following each U line, is a series of lines of the form 346 347 -- W unit-name [source-name lib-name] [E] [EA] [ED] 348 -- 349 -- One of these lines is present for each unit that is mentioned in 350 -- an explicit with clause by the current unit. The first parameter 351 -- is the unit name in internal format. The second parameter is the 352 -- file name of the file that must be compiled to compile this unit 353 -- (which is usually the file for the body, except for packages 354 -- which have no body). The third parameter is the file name of the 355 -- library information file that contains the results of compiling 356 -- this unit. The optional modifiers are used as follows: 357 -- 358 -- E pragma Elaborate applies to this unit 359 -- 360 -- EA pragma Elaborate_All applies to this unit 361 -- 362 -- ED Elaborate_All_Desirable set for this unit, which means 363 -- that there is no Elaborate_All, but the analysis suggests 364 -- that Program_Error may be raised if the Elaborate_All 365 -- conditions cannot be satisfied. The binder will attempt 366 -- to treat ED as EA if it can. 367 -- 368 -- The parameter source-name and lib-name are omitted for the case 369 -- of a generic unit compiled with earlier versions of GNAT which 370 -- did not generate object or ali files for generics. 371 372 -- ----------------------- 373 -- -- L Linker_Options -- 374 -- ----------------------- 375 376 -- Following the W lines (if any, or the U line if not), are an 377 -- optional series of lines that indicates the usage of the pragma 378 -- Linker_Options in the associated unit. For each appearence of a 379 -- pragma Linker_Options (or Link_With) in the unit, a line is 380 -- present with the form: 381 382 -- L "string" 383 384 -- where string is the string from the unit line enclosed in quotes. 385 -- Within the quotes the following can occur: 386 387 -- c graphic characters in range 20-7E other than " or { 388 -- "" indicating a single " character 389 -- {hh} indicating a character whose code is hex hh (0-9,A-F) 390 -- {00} [ASCII.NUL] is used as a separator character 391 -- to separate multiple arguments of a single 392 -- Linker_Options pragma. 393 394 -- For further details, see Stringt.Write_String_Table_Entry. Note 395 -- that wide characters in the form {hhhh} cannot be produced, since 396 -- pragma Linker_Option accepts only String, not Wide_String. 397 398 -- The L lines are required to appear in the same order as the 399 -- corresponding Linker_Options (or Link_With) pragmas appear in 400 -- the source file, so that this order is preserved by the binder 401 -- in constructing the set of linker arguments. 402 403 --------------------- 404 -- Reference Lines -- 405 --------------------- 406 407 -- The reference lines contain information about references from 408 -- any of the units in the compilation (including, body version 409 -- and version attributes, linker options pragmas and source 410 -- dependencies. 411 412 -- ------------------------------------ 413 -- -- E External Version References -- 414 -- ------------------------------------ 415 416 -- One of these lines is present for each use of 'Body_Version or 417 -- 'Version in any of the units of the compilation. These are used 418 -- by the linker to determine which version symbols must be output. 419 -- The format is simply: 420 421 -- E name 422 423 -- where name is the external name, i.e. the unit name with either 424 -- a S or a B for spec or body version referenced (Body_Version 425 -- always references the body, Version references the Spec, except 426 -- in the case of a reference to a subprogram with no separate spec). 427 -- Upper half and wide character codes are encoded using the same 428 -- method as in Namet (Uhh for upper half, Whhhh for wide character, 429 -- where hh are hex digits). 430 431 -- --------------------- 432 -- -- D Dependencies -- 433 -- --------------------- 434 435 -- The dependency lines indicate the source files on which the compiled 436 -- units depend. This is used by the binder for consistency checking. 437 -- These lines are also referenced by the cross-reference information. 438 439 -- D source-name time-stamp checksum [subunit-name] line:file-name 440 441 -- The time-stamp field contains the time stamp of the 442 -- corresponding source file. See types.ads for details on 443 -- time stamp representation. 444 445 -- The checksum is an 8-hex digit representation of the source 446 -- file checksum, with letters given in lower case. 447 448 -- The subunit name is present only if the dependency line is for 449 -- a subunit. It contains the fully qualified name of the subunit 450 -- in all lower case letters. 451 452 -- The line:file-name entry is present only if a Source_Reference 453 -- pragma appeared in the source file identified by source-name. 454 -- In this case, it gives the information from this pragma. Note 455 -- that this allows cross-reference information to be related back 456 -- to the original file. Note: the reason the line number comes 457 -- first is that a leading digit immediately identifies this as 458 -- a Source_Reference entry, rather than a subunit-name. 459 460 -- A line number of zero for line: in this entry indicates that 461 -- there is more than one source reference pragma. In this case, 462 -- the line numbers in the cross-reference are correct, and refer 463 -- to the original line number, but there is no information that 464 -- allows a reader of the ALI file to determine the exact mapping 465 -- of physical line numbers back to the original source. 466 467 -- Files with a zero checksum and a non-zero time stamp are in general 468 -- files on which the compilation depends but which are not Ada files 469 -- with further dependencies. This includes preprocessor data files 470 -- and preprocessor definition files. 471 472 -- Note: blank lines are ignored when the library information is 473 -- read, and separate sections of the file are separated by blank 474 -- lines to ease readability. Blanks between fields are also 475 -- ignored. 476 477 -- For entries corresponding to files that were not present (and 478 -- thus resulted in error messages), or for files that are not 479 -- part of the dependency set, both the time stamp and checksum 480 -- are set to all zero characters. These dummy entries are ignored 481 -- by the binder in dependency checking, but must be present for 482 -- proper interpretation of the cross-reference data. 483 484 -------------------------- 485 -- Cross-Reference Data -- 486 -------------------------- 487 488 -- The cross-reference data follows the dependency lines. See 489 -- the spec of Lib.Xref for details on the format of this data. 490 491 ---------------------- 492 -- Global_Variables -- 493 ---------------------- 494 495 -- The table structure defined here stores one entry for each 496 -- Interrupt_State pragma encountered either in the main source or 497 -- in an ancillary with'ed source. Since interrupt state values 498 -- have to be consistent across all units in a partition, we may 499 -- as well detect inconsistencies at compile time when we can. 500 501 type Interrupt_State_Entry is record 502 Interrupt_Number : Pos; 503 -- Interrupt number value 504 505 Interrupt_State : Character; 506 -- Set to r/s/u for Runtime/System/User 507 508 Pragma_Loc : Source_Ptr; 509 -- Location of pragma setting this value in place 510 end record; 511 512 package Interrupt_States is new Table.Table ( 513 Table_Component_Type => Interrupt_State_Entry, 514 Table_Index_Type => Nat, 515 Table_Low_Bound => 1, 516 Table_Initial => 30, 517 Table_Increment => 200, 518 Table_Name => "Name_Interrupt_States"); 519 520 ----------------- 521 -- Subprograms -- 522 ----------------- 523 524 procedure Ensure_System_Dependency; 525 -- This procedure ensures that a dependency is created on system.ads. 526 -- Even if there is no semantic dependency, Targparm has read the 527 -- file to acquire target parameters, so we need a source dependency. 528 529 procedure Write_ALI (Object : Boolean); 530 -- This procedure writes the library information for the current main unit 531 -- The Object parameter is true if an object file is created, and false 532 -- otherwise. 533 -- 534 -- Note: in the case where we are not generating code (-gnatc mode), this 535 -- routine only writes an ALI file if it cannot find an existing up to 536 -- date ALI file. If it *can* find an existing up to date ALI file, then 537 -- it reads this file and sets the Lib.Compilation_Arguments table from 538 -- the A lines in this file. 539 540 procedure Add_Preprocessing_Dependency (S : Source_File_Index); 541 -- Indicate that there is a dependency to be added on a preprocessing 542 -- data file or on a preprocessing definition file. 543 544end Lib.Writ; 545