gcc/gcc.info-27

   1 This is Info file gcc.info, produced by Makeinfo version 1.68 from the
   2 input file gcc.texi.
   3
   4    This file documents the use and the internals of the GNU compiler.
   5
   6    Published by the Free Software Foundation 59 Temple Place - Suite 330
   7 Boston, MA 02111-1307 USA
   8
   9    Copyright (C) 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997 Free
  10 Software Foundation, Inc.
  11
  12    Permission is granted to make and distribute verbatim copies of this
  13 manual provided the copyright notice and this permission notice are
  14 preserved on all copies.
  15
  16    Permission is granted to copy and distribute modified versions of
  17 this manual under the conditions for verbatim copying, provided also
  18 that the sections entitled "GNU General Public License," "Funding for
  19 Free Software," and "Protect Your Freedom--Fight `Look And Feel'" are
  20 included exactly as in the original, and provided that the entire
  21 resulting derived work is distributed under the terms of a permission
  22 notice identical to this one.
  23
  24    Permission is granted to copy and distribute translations of this
  25 manual into another language, under the above conditions for modified
  26 versions, except that the sections entitled "GNU General Public
  27 License," "Funding for Free Software," and "Protect Your Freedom--Fight
  28 `Look And Feel'", and this permission notice, may be included in
  29 translations approved by the Free Software Foundation instead of in the
  30 original English.
  31
  32 \1f
  33 File: gcc.info,  Node: Copying,  Next: Contributors,  Prev: Look and Feel,  Up: Top
  34
  35 GNU GENERAL PUBLIC LICENSE
  36 **************************
  37
  38                          Version 2, June 1991
  39
  40      Copyright (C) 1989, 1991 Free Software Foundation, Inc.
  41      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  42
  43      Everyone is permitted to copy and distribute verbatim copies
  44      of this license document, but changing it is not allowed.
  45
  46 Preamble
  47 ========
  48
  49    The licenses for most software are designed to take away your
  50 freedom to share and change it.  By contrast, the GNU General Public
  51 License is intended to guarantee your freedom to share and change free
  52 software--to make sure the software is free for all its users.  This
  53 General Public License applies to most of the Free Software
  54 Foundation's software and to any other program whose authors commit to
  55 using it.  (Some other Free Software Foundation software is covered by
  56 the GNU Library General Public License instead.)  You can apply it to
  57 your programs, too.
  58
  59    When we speak of free software, we are referring to freedom, not
  60 price.  Our General Public Licenses are designed to make sure that you
  61 have the freedom to distribute copies of free software (and charge for
  62 this service if you wish), that you receive source code or can get it
  63 if you want it, that you can change the software or use pieces of it in
  64 new free programs; and that you know you can do these things.
  65
  66    To protect your rights, we need to make restrictions that forbid
  67 anyone to deny you these rights or to ask you to surrender the rights.
  68 These restrictions translate to certain responsibilities for you if you
  69 distribute copies of the software, or if you modify it.
  70
  71    For example, if you distribute copies of such a program, whether
  72 gratis or for a fee, you must give the recipients all the rights that
  73 you have.  You must make sure that they, too, receive or can get the
  74 source code.  And you must show them these terms so they know their
  75 rights.
  76
  77    We protect your rights with two steps: (1) copyright the software,
  78 and (2) offer you this license which gives you legal permission to copy,
  79 distribute and/or modify the software.
  80
  81    Also, for each author's protection and ours, we want to make certain
  82 that everyone understands that there is no warranty for this free
  83 software.  If the software is modified by someone else and passed on, we
  84 want its recipients to know that what they have is not the original, so
  85 that any problems introduced by others will not reflect on the original
  86 authors' reputations.
  87
  88    Finally, any free program is threatened constantly by software
  89 patents.  We wish to avoid the danger that redistributors of a free
  90 program will individually obtain patent licenses, in effect making the
  91 program proprietary.  To prevent this, we have made it clear that any
  92 patent must be licensed for everyone's free use or not licensed at all.
  93
  94    The precise terms and conditions for copying, distribution and
  95 modification follow.
  96
  97     TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
  98
  99   0. This License applies to any program or other work which contains a
 100      notice placed by the copyright holder saying it may be distributed
 101      under the terms of this General Public License.  The "Program",
 102      below, refers to any such program or work, and a "work based on
 103      the Program" means either the Program or any derivative work under
 104      copyright law: that is to say, a work containing the Program or a
 105      portion of it, either verbatim or with modifications and/or
 106      translated into another language.  (Hereinafter, translation is
 107      included without limitation in the term "modification".)  Each
 108      licensee is addressed as "you".
 109
 110      Activities other than copying, distribution and modification are
 111      not covered by this License; they are outside its scope.  The act
 112      of running the Program is not restricted, and the output from the
 113      Program is covered only if its contents constitute a work based on
 114      the Program (independent of having been made by running the
 115      Program).  Whether that is true depends on what the Program does.
 116
 117   1. You may copy and distribute verbatim copies of the Program's
 118      source code as you receive it, in any medium, provided that you
 119      conspicuously and appropriately publish on each copy an appropriate
 120      copyright notice and disclaimer of warranty; keep intact all the
 121      notices that refer to this License and to the absence of any
 122      warranty; and give any other recipients of the Program a copy of
 123      this License along with the Program.
 124
 125      You may charge a fee for the physical act of transferring a copy,
 126      and you may at your option offer warranty protection in exchange
 127      for a fee.
 128
 129   2. You may modify your copy or copies of the Program or any portion
 130      of it, thus forming a work based on the Program, and copy and
 131      distribute such modifications or work under the terms of Section 1
 132      above, provided that you also meet all of these conditions:
 133
 134        a. You must cause the modified files to carry prominent notices
 135           stating that you changed the files and the date of any change.
 136
 137        b. You must cause any work that you distribute or publish, that
 138           in whole or in part contains or is derived from the Program
 139           or any part thereof, to be licensed as a whole at no charge
 140           to all third parties under the terms of this License.
 141
 142        c. If the modified program normally reads commands interactively
 143           when run, you must cause it, when started running for such
 144           interactive use in the most ordinary way, to print or display
 145           an announcement including an appropriate copyright notice and
 146           a notice that there is no warranty (or else, saying that you
 147           provide a warranty) and that users may redistribute the
 148           program under these conditions, and telling the user how to
 149           view a copy of this License.  (Exception: if the Program
 150           itself is interactive but does not normally print such an
 151           announcement, your work based on the Program is not required
 152           to print an announcement.)
 153
 154      These requirements apply to the modified work as a whole.  If
 155      identifiable sections of that work are not derived from the
 156      Program, and can be reasonably considered independent and separate
 157      works in themselves, then this License, and its terms, do not
 158      apply to those sections when you distribute them as separate
 159      works.  But when you distribute the same sections as part of a
 160      whole which is a work based on the Program, the distribution of
 161      the whole must be on the terms of this License, whose permissions
 162      for other licensees extend to the entire whole, and thus to each
 163      and every part regardless of who wrote it.
 164
 165      Thus, it is not the intent of this section to claim rights or
 166      contest your rights to work written entirely by you; rather, the
 167      intent is to exercise the right to control the distribution of
 168      derivative or collective works based on the Program.
 169
 170      In addition, mere aggregation of another work not based on the
 171      Program with the Program (or with a work based on the Program) on
 172      a volume of a storage or distribution medium does not bring the
 173      other work under the scope of this License.
 174
 175   3. You may copy and distribute the Program (or a work based on it,
 176      under Section 2) in object code or executable form under the terms
 177      of Sections 1 and 2 above provided that you also do one of the
 178      following:
 179
 180        a. Accompany it with the complete corresponding machine-readable
 181           source code, which must be distributed under the terms of
 182           Sections 1 and 2 above on a medium customarily used for
 183           software interchange; or,
 184
 185        b. Accompany it with a written offer, valid for at least three
 186           years, to give any third party, for a charge no more than your
 187           cost of physically performing source distribution, a complete
 188           machine-readable copy of the corresponding source code, to be
 189           distributed under the terms of Sections 1 and 2 above on a
 190           medium customarily used for software interchange; or,
 191
 192        c. Accompany it with the information you received as to the offer
 193           to distribute corresponding source code.  (This alternative is
 194           allowed only for noncommercial distribution and only if you
 195           received the program in object code or executable form with
 196           such an offer, in accord with Subsection b above.)
 197
 198      The source code for a work means the preferred form of the work for
 199      making modifications to it.  For an executable work, complete
 200      source code means all the source code for all modules it contains,
 201      plus any associated interface definition files, plus the scripts
 202      used to control compilation and installation of the executable.
 203      However, as a special exception, the source code distributed need
 204      not include anything that is normally distributed (in either
 205      source or binary form) with the major components (compiler,
 206      kernel, and so on) of the operating system on which the executable
 207      runs, unless that component itself accompanies the executable.
 208
 209      If distribution of executable or object code is made by offering
 210      access to copy from a designated place, then offering equivalent
 211      access to copy the source code from the same place counts as
 212      distribution of the source code, even though third parties are not
 213      compelled to copy the source along with the object code.
 214
 215   4. You may not copy, modify, sublicense, or distribute the Program
 216      except as expressly provided under this License.  Any attempt
 217      otherwise to copy, modify, sublicense or distribute the Program is
 218      void, and will automatically terminate your rights under this
 219      License.  However, parties who have received copies, or rights,
 220      from you under this License will not have their licenses
 221      terminated so long as such parties remain in full compliance.
 222
 223   5. You are not required to accept this License, since you have not
 224      signed it.  However, nothing else grants you permission to modify
 225      or distribute the Program or its derivative works.  These actions
 226      are prohibited by law if you do not accept this License.
 227      Therefore, by modifying or distributing the Program (or any work
 228      based on the Program), you indicate your acceptance of this
 229      License to do so, and all its terms and conditions for copying,
 230      distributing or modifying the Program or works based on it.
 231
 232   6. Each time you redistribute the Program (or any work based on the
 233      Program), the recipient automatically receives a license from the
 234      original licensor to copy, distribute or modify the Program
 235      subject to these terms and conditions.  You may not impose any
 236      further restrictions on the recipients' exercise of the rights
 237      granted herein.  You are not responsible for enforcing compliance
 238      by third parties to this License.
 239
 240   7. If, as a consequence of a court judgment or allegation of patent
 241      infringement or for any other reason (not limited to patent
 242      issues), conditions are imposed on you (whether by court order,
 243      agreement or otherwise) that contradict the conditions of this
 244      License, they do not excuse you from the conditions of this
 245      License.  If you cannot distribute so as to satisfy simultaneously
 246      your obligations under this License and any other pertinent
 247      obligations, then as a consequence you may not distribute the
 248      Program at all.  For example, if a patent license would not permit
 249      royalty-free redistribution of the Program by all those who
 250      receive copies directly or indirectly through you, then the only
 251      way you could satisfy both it and this License would be to refrain
 252      entirely from distribution of the Program.
 253
 254      If any portion of this section is held invalid or unenforceable
 255      under any particular circumstance, the balance of the section is
 256      intended to apply and the section as a whole is intended to apply
 257      in other circumstances.
 258
 259      It is not the purpose of this section to induce you to infringe any
 260      patents or other property right claims or to contest validity of
 261      any such claims; this section has the sole purpose of protecting
 262      the integrity of the free software distribution system, which is
 263      implemented by public license practices.  Many people have made
 264      generous contributions to the wide range of software distributed
 265      through that system in reliance on consistent application of that
 266      system; it is up to the author/donor to decide if he or she is
 267      willing to distribute software through any other system and a
 268      licensee cannot impose that choice.
 269
 270      This section is intended to make thoroughly clear what is believed
 271      to be a consequence of the rest of this License.
 272
 273   8. If the distribution and/or use of the Program is restricted in
 274      certain countries either by patents or by copyrighted interfaces,
 275      the original copyright holder who places the Program under this
 276      License may add an explicit geographical distribution limitation
 277      excluding those countries, so that distribution is permitted only
 278      in or among countries not thus excluded.  In such case, this
 279      License incorporates the limitation as if written in the body of
 280      this License.
 281
 282   9. The Free Software Foundation may publish revised and/or new
 283      versions of the General Public License from time to time.  Such
 284      new versions will be similar in spirit to the present version, but
 285      may differ in detail to address new problems or concerns.
 286
 287      Each version is given a distinguishing version number.  If the
 288      Program specifies a version number of this License which applies
 289      to it and "any later version", you have the option of following
 290      the terms and conditions either of that version or of any later
 291      version published by the Free Software Foundation.  If the Program
 292      does not specify a version number of this License, you may choose
 293      any version ever published by the Free Software Foundation.
 294
 295  10. If you wish to incorporate parts of the Program into other free
 296      programs whose distribution conditions are different, write to the
 297      author to ask for permission.  For software which is copyrighted
 298      by the Free Software Foundation, write to the Free Software
 299      Foundation; we sometimes make exceptions for this.  Our decision
 300      will be guided by the two goals of preserving the free status of
 301      all derivatives of our free software and of promoting the sharing
 302      and reuse of software generally.
 303
 304                                 NO WARRANTY
 305
 306  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO
 307      WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE
 308      LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
 309      HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT
 310      WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT
 311      NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 312      FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS TO THE
 313      QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
 314      PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY
 315      SERVICING, REPAIR OR CORRECTION.
 316
 317  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
 318      WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY
 319      MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE
 320      LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL,
 321      INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR
 322      INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
 323      DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU
 324      OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY
 325      OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN
 326      ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 327
 328                       END OF TERMS AND CONDITIONS
 329
 330 How to Apply These Terms to Your New Programs
 331 =============================================
 332
 333    If you develop a new program, and you want it to be of the greatest
 334 possible use to the public, the best way to achieve this is to make it
 335 free software which everyone can redistribute and change under these
 336 terms.
 337
 338    To do so, attach the following notices to the program.  It is safest
 339 to attach them to the start of each source file to most effectively
 340 convey the exclusion of warranty; and each file should have at least
 341 the "copyright" line and a pointer to where the full notice is found.
 342
 343      ONE LINE TO GIVE THE PROGRAM'S NAME AND A BRIEF IDEA OF WHAT IT DOES.
 344      Copyright (C) 19YY  NAME OF AUTHOR
 345
 346      This program is free software; you can redistribute it and/or modify
 347      it under the terms of the GNU General Public License as published by
 348      the Free Software Foundation; either version 2 of the License, or
 349      (at your option) any later version.
 350
 351      This program is distributed in the hope that it will be useful,
 352      but WITHOUT ANY WARRANTY; without even the implied warranty of
 353      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 354      GNU General Public License for more details.
 355
 356      You should have received a copy of the GNU General Public License
 357      along with this program; if not, write to the Free Software
 358      Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 359
 360    Also add information on how to contact you by electronic and paper
 361 mail.
 362
 363    If the program is interactive, make it output a short notice like
 364 this when it starts in an interactive mode:
 365
 366      Gnomovision version 69, Copyright (C) 19YY NAME OF AUTHOR
 367      Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
 368      type `show w'.
 369      This is free software, and you are welcome to redistribute it
 370      under certain conditions; type `show c' for details.
 371
 372    The hypothetical commands `show w' and `show c' should show the
 373 appropriate parts of the General Public License.  Of course, the
 374 commands you use may be called something other than `show w' and `show
 375 c'; they could even be mouse-clicks or menu items--whatever suits your
 376 program.
 377
 378    You should also get your employer (if you work as a programmer) or
 379 your school, if any, to sign a "copyright disclaimer" for the program,
 380 if necessary.  Here is a sample; alter the names:
 381
 382      Yoyodyne, Inc., hereby disclaims all copyright interest in the program
 383      `Gnomovision' (which makes passes at compilers) written by James Hacker.
 384
 385      SIGNATURE OF TY COON, 1 April 1989
 386      Ty Coon, President of Vice
 387
 388    This General Public License does not permit incorporating your
 389 program into proprietary programs.  If your program is a subroutine
 390 library, you may consider it more useful to permit linking proprietary
 391 applications with the library.  If this is what you want to do, use the
 392 GNU Library General Public License instead of this License.
 393
 394 \1f
 395 File: gcc.info,  Node: Contributors,  Next: Index,  Prev: Copying,  Up: Top
 396
 397 Contributors to GNU CC
 398 **********************
 399
 400    In addition to Richard Stallman, several people have written parts
 401 of GNU CC.
 402
 403    * The idea of using RTL and some of the optimization ideas came from
 404      the program PO written at the University of Arizona by Jack
 405      Davidson and Christopher Fraser.  See "Register Allocation and
 406      Exhaustive Peephole Optimization", Software Practice and
 407      Experience 14 (9), Sept. 1984, 857-866.
 408
 409    * Paul Rubin wrote most of the preprocessor.
 410
 411    * Leonard Tower wrote parts of the parser, RTL generator, and RTL
 412      definitions, and of the Vax machine description.
 413
 414    * Ted Lemon wrote parts of the RTL reader and printer.
 415
 416    * Jim Wilson implemented loop strength reduction and some other loop
 417      optimizations.
 418
 419    * Nobuyuki Hikichi of Software Research Associates, Tokyo,
 420      contributed the support for the Sony NEWS machine.
 421
 422    * Charles LaBrec contributed the support for the Integrated Solutions
 423      68020 system.
 424
 425    * Michael Tiemann of Cygnus Support wrote the front end for C++, as
 426      well as the support for inline functions and instruction
 427      scheduling.  Also the descriptions of the National Semiconductor
 428      32000 series cpu, the SPARC cpu and part of the Motorola 88000 cpu.
 429
 430    * Gerald Baumgartner added the signature extension to the C++
 431      front-end.
 432
 433    * Jan Stein of the Chalmers Computer Society provided support for
 434      Genix, as well as part of the 32000 machine description.
 435
 436    * Randy Smith finished the Sun FPA support.
 437
 438    * Robert Brown implemented the support for Encore 32000 systems.
 439
 440    * David Kashtan of SRI adapted GNU CC to VMS.
 441
 442    * Alex Crain provided changes for the 3b1.
 443
 444    * Greg Satz and Chris Hanson assisted in making GNU CC work on HP-UX
 445      for the 9000 series 300.
 446
 447    * William Schelter did most of the work on the Intel 80386 support.
 448
 449    * Christopher Smith did the port for Convex machines.
 450
 451    * Paul Petersen wrote the machine description for the Alliant FX/8.
 452
 453    * Dario Dariol contributed the four varieties of sample programs
 454      that print a copy of their source.
 455
 456    * Alain Lichnewsky ported GNU CC to the Mips cpu.
 457
 458    * Devon Bowen, Dale Wiles and Kevin Zachmann ported GNU CC to the
 459      Tahoe.
 460
 461    * Jonathan Stone wrote the machine description for the Pyramid
 462      computer.
 463
 464    * Gary Miller ported GNU CC to Charles River Data Systems machines.
 465
 466    * Richard Kenner of the New York University Ultracomputer Research
 467      Laboratory wrote the machine descriptions for the AMD 29000, the
 468      DEC Alpha, the IBM RT PC, and the IBM RS/6000 as well as the
 469      support for instruction attributes.  He also made changes to
 470      better support RISC processors including changes to common
 471      subexpression elimination, strength reduction, function calling
 472      sequence handling, and condition code support, in addition to
 473      generalizing the code for frame pointer elimination.
 474
 475    * Richard Kenner and Michael Tiemann jointly developed reorg.c, the
 476      delay slot scheduler.
 477
 478    * Mike Meissner and Tom Wood of Data General finished the port to the
 479      Motorola 88000.
 480
 481    * Masanobu Yuhara of Fujitsu Laboratories implemented the machine
 482      description for the Tron architecture (specifically, the Gmicro).
 483
 484    * NeXT, Inc. donated the front end that supports the Objective C
 485      language.
 486
 487    * James van Artsdalen wrote the code that makes efficient use of the
 488      Intel 80387 register stack.
 489
 490    * Mike Meissner at the Open Software Foundation finished the port to
 491      the MIPS cpu, including adding ECOFF debug support, and worked on
 492      the Intel port for the Intel 80386 cpu.  Later at Cygnus Support,
 493      he worked on the rs6000 and PowerPC ports.
 494
 495    * Ron Guilmette implemented the `protoize' and `unprotoize' tools,
 496      the support for Dwarf symbolic debugging information, and much of
 497      the support for System V Release 4.  He has also worked heavily on
 498      the Intel 386 and 860 support.
 499
 500    * Torbjorn Granlund implemented multiply- and divide-by-constant
 501      optimization, improved long long support, and improved leaf
 502      function register allocation.
 503
 504    * Mike Stump implemented the support for Elxsi 64 bit CPU.
 505
 506    * John Wehle added the machine description for the Western Electric
 507      32000 processor used in several 3b series machines (no relation to
 508      the National Semiconductor 32000 processor).
 509
 510    * Holger Teutsch provided the support for the Clipper cpu.
 511
 512    * Kresten Krab Thorup wrote the run time support for the Objective C
 513      language.
 514
 515    * Stephen Moshier contributed the floating point emulator that
 516      assists in cross-compilation and permits support for floating
 517      point numbers wider than 64 bits.
 518
 519    * David Edelsohn contributed the changes to RS/6000 port to make it
 520      support the PowerPC and POWER2 architectures.
 521
 522    * Steve Chamberlain wrote the support for the Hitachi SH processor.
 523
 524    * Peter Schauer wrote the code to allow debugging to work on the
 525      Alpha.
 526
 527    * Oliver M. Kellogg of Deutsche Aerospace contributed the port to the
 528      MIL-STD-1750A.
 529
 530    * Michael K. Gschwind contributed the port to the PDP-11.
 531
 532    * David Reese of Sun Microsystems contributed to the Solaris on
 533      PowerPC port.
 534