1G77(1) GNU G77(1)
2
6 g77 - GNU project Fortran 77 compiler
7
9 g77 [-c|-S|-E]
10 [-g] [-pg] [-Olevel]
11 [-Wwarn...] [-pedantic]
12 [-Idir...] [-Ldir...]
13 [-Dmacro[=defn]...] [-Umacro]
14 [-foption...] [-mmachine-option...]
15 [-o outfile] infile...
16 Only the most useful options are listed here; see below for the
18 remainder.
19
21 The g77 command supports all the options supported by the gcc command.
22 All gcc and g77 options are accepted both by g77 and by gcc (as well as
24 any other drivers built at the same time, such as g++), since adding
25 g77 to the gcc distribution enables acceptance of g77 options by all of
26 the relevant drivers.
27 In some cases, options have positive and negative forms; the negative
29 form of -ffoo would be -fno-foo. This manual documents only one of
30 these two forms, whichever one is not the default.
31
33 Here is a summary of all the options specific to GNU Fortran, grouped
34 by type. Explanations are in the following sections.
35 Overall Options
37 -fversion -fset-g77-defaults -fno-silent
38 Shorthand Options
40 -ff66 -fno-f66 -ff77 -fno-f77 -fno-ugly
41 Fortran Language Options
43 -ffree-form -fno-fixed-form -ff90 -fvxt -fdollar-ok
44 -fno-backslash -fno-ugly-args -fno-ugly-assign -fno-ugly-assumed
45 -fugly-comma -fugly-complex -fugly-init -fugly-logint -fonetrip
46 -ftypeless-boz -fintrin-case-initcap -fintrin-case-upper
47 -fintrin-case-lower -fintrin-case-any -fmatch-case-initcap
48 -fmatch-case-upper -fmatch-case-lower -fmatch-case-any
49 -fsource-case-upper -fsource-case-lower -fsource-case-preserve
50 -fsymbol-case-initcap -fsymbol-case-upper -fsymbol-case-lower
51 -fsymbol-case-any -fcase-strict-upper -fcase-strict-lower
52 -fcase-initcap -fcase-upper -fcase-lower -fcase-preserve
53 -ff2c-intrinsics-delete -ff2c-intrinsics-hide
54 -ff2c-intrinsics-disable -ff2c-intrinsics-enable
55 -fbadu77-intrinsics-delete -fbadu77-intrinsics-hide
56 -fbadu77-intrinsics-disable -fbadu77-intrinsics-enable
57 -ff90-intrinsics-delete -ff90-intrinsics-hide
58 -ff90-intrinsics-disable -ff90-intrinsics-enable
59 -fgnu-intrinsics-delete -fgnu-intrinsics-hide
60 -fgnu-intrinsics-disable -fgnu-intrinsics-enable
61 -fmil-intrinsics-delete -fmil-intrinsics-hide
62 -fmil-intrinsics-disable -fmil-intrinsics-enable
63 -funix-intrinsics-delete -funix-intrinsics-hide
64 -funix-intrinsics-disable -funix-intrinsics-enable
65 -fvxt-intrinsics-delete -fvxt-intrinsics-hide
66 -fvxt-intrinsics-disable -fvxt-intrinsics-enable
67 -ffixed-line-length-n -ffixed-line-length-none
68 Warning Options
70 -fsyntax-only -pedantic -pedantic-errors -fpedantic -w
71 -Wno-globals -Wimplicit -Wunused -Wuninitialized -Wall
72 -Wsurprising -Werror -W
73 Debugging Options
75 -g
76 Optimization Options
78 -malign-double -ffloat-store -fforce-mem -fforce-addr
79 -fno-inline -ffast-math -fstrength-reduce -frerun-cse-after-loop
80 -funsafe-math-optimizations -ffinite-math-only -fno-trapping-math
81 -fexpensive-optimizations -fdelayed-branch -fschedule-insns
82 -fschedule-insn2 -fcaller-saves -funroll-loops -funroll-all-loops
83 -fno-move-all-movables -fno-reduce-all-givs -fno-rerun-loop-opt
84 Directory Options
86 -Idir -I-
87 Code Generation Options
89 -fno-automatic -finit-local-zero -fno-f2c -ff2c-library
90 -fno-underscoring -fno-ident -fpcc-struct-return
91 -freg-struct-return -fshort-double -fno-common -fpack-struct
92 -fzeros -fno-second-underscore -femulate-complex -falias-check
93 -fargument-alias -fargument-noalias -fno-argument-noalias-global
94 -fno-globals -fflatten-arrays -fbounds-check
95 -ffortran-bounds-check
96 Compilation can involve as many as four stages: preprocessing, code
98 generation (often what is really meant by the term ``compilation''),
99 assembly, and linking, always in that order. The first three stages
100 apply to an individual source file, and end by producing an object
101 file; linking combines all the object files (those newly compiled, and
102 those specified as input) into an executable file.
103 For any given input file, the file name suffix determines what kind of
105 program is contained in the file---that is, the language in which the
106 program is written is generally indicated by the suffix. Suffixes
107 specific to GNU Fortran are listed below.
108 file.f
110 file.for
111 file.FOR
112 Fortran source code that should not be preprocessed.
113 Such source code cannot contain any preprocessor directives, such
115 as "#include", "#define", "#if", and so on.
116 You can force .f files to be preprocessed by cpp by using -x
118 f77-cpp-input.
119 file.F
121 file.fpp
122 file.FPP
123 Fortran source code that must be preprocessed (by the C
124 preprocessor cpp, which is part of GCC).
125 Note that preprocessing is not extended to the contents of files
127 included by the "INCLUDE" directive---the "#include" preprocessor
128 directive must be used instead.
129 file.r
131 Ratfor source code, which must be preprocessed by the ratfor
132 command, which is available separately (as it is not yet part of
133 the GNU Fortran distribution). A public domain version in C is at
134 <http://sepwww.stanford.edu/sep/prof/ratfor.shar.2>.
135 UNIX users typically use the file.f and file.F nomenclature. Users of
137 other operating systems, especially those that cannot distinguish
138 upper-case letters from lower-case letters in their file names,
139 typically use the file.for and file.fpp nomenclature.
140 Use of the preprocessor cpp allows use of C-like constructs such as
142 "#define" and "#include", but can lead to unexpected, even mistaken,
143 results due to Fortran's source file format. It is recommended that
144 use of the C preprocessor be limited to "#include" and, in conjunction
145 with "#define", only "#if" and related directives, thus avoiding in-
146 line macro expansion entirely. This recommendation applies especially
147 when using the traditional fixed source form. With free source form,
148 fewer unexpected transformations are likely to happen, but use of
149 constructs such as Hollerith and character constants can nevertheless
150 present problems, especially when these are continued across multiple
151 source lines. These problems result, primarily, from differences
152 between the way such constants are interpreted by the C preprocessor
153 and by a Fortran compiler.
154 Another example of a problem that results from using the C preprocessor
156 is that a Fortran comment line that happens to contain any characters
157 ``interesting'' to the C preprocessor, such as a backslash at the end
158 of the line, is not recognized by the preprocessor as a comment line,
159 so instead of being passed through ``raw'', the line is edited
160 according to the rules for the preprocessor. For example, the
161 backslash at the end of the line is removed, along with the subsequent
162 newline, resulting in the next line being effectively commented
163 out---unfortunate if that line is a non-comment line of important code!
164 Note: The -traditional and -undef flags are supplied to cpp by default,
166 to help avoid unpleasant surprises.
167 This means that ANSI C preprocessor features (such as the # operator)
169 aren't available, and only variables in the C reserved namespace
170 (generally, names with a leading underscore) are liable to substitution
171 by C predefines. Thus, if you want to do system-specific tests, use,
172 for example, #ifdef __linux__ rather than #ifdef linux. Use the -v
173 option to see exactly how the preprocessor is invoked.
174 Unfortunately, the -traditional flag will not avoid an error from
176 anything that cpp sees as an unterminated C comment, such as:
177 C Some Fortran compilers accept /* as starting
179 C an inline comment.
180 The following options that affect overall processing are recognized by
182 the g77 and gcc commands in a GNU Fortran installation:
183 -fversion
185 Ensure that the g77 version of the compiler phase is reported, if
186 run, and, starting in "egcs" version 1.1, that internal consistency
187 checks in the f771 program are run.
188 This option is supplied automatically when -v or --verbose is
190 specified as a command-line option for g77 or gcc and when the
191 resulting commands compile Fortran source files.
192 In GCC 3.1, this is changed back to the behavior gcc displays for
194 .c files.
195 -fset-g77-defaults
197 Version info: This option was obsolete as of "egcs" version 1.1.
198 The effect is instead achieved by the "lang_init_options" routine
199 in gcc/gcc/f/com.c.
200 Set up whatever gcc options are to apply to Fortran compilations,
202 and avoid running internal consistency checks that might take some
203 time.
204 This option is supplied automatically when compiling Fortran code
206 via the g77 or gcc command. The description of this option is
207 provided so that users seeing it in the output of, say, g77 -v
208 understand why it is there.
209 Also, developers who run "f771" directly might want to specify it
211 by hand to get the same defaults as they would running "f771" via
212 g77 or gcc However, such developers should, after linking a new
213 "f771" executable, invoke it without this option once, e.g. via
214 "./f771 -quiet < /dev/null", to ensure that they have not
215 introduced any internal inconsistencies (such as in the table of
216 intrinsics) before proceeding---g77 will crash with a diagnostic if
217 it detects an inconsistency.
218 -fno-silent
220 Print (to "stderr") the names of the program units as they are
221 compiled, in a form similar to that used by popular UNIX f77
222 implementations and f2c
223 Shorthand Options
225 The following options serve as ``shorthand'' for other options accepted
226 by the compiler:
227 -fugly
229 Note: This option is no longer supported. The information, below,
230 is provided to aid in the conversion of old scripts.
231 Specify that certain ``ugly'' constructs are to be quietly
233 accepted. Same as:
234 -fugly-args -fugly-assign -fugly-assumed
236 -fugly-comma -fugly-complex -fugly-init
237 -fugly-logint
238 These constructs are considered inappropriate to use in new or
240 well-maintained portable Fortran code, but widely used in old code.
241 -fno-ugly
243 Specify that all ``ugly'' constructs are to be noisily rejected.
244 Same as:
245 -fno-ugly-args -fno-ugly-assign -fno-ugly-assumed
247 -fno-ugly-comma -fno-ugly-complex -fno-ugly-init
248 -fno-ugly-logint
249 -ff66
251 Specify that the program is written in idiomatic FORTRAN 66. Same
252 as -fonetrip -fugly-assumed.
253 The -fno-f66 option is the inverse of -ff66. As such, it is the
255 same as -fno-onetrip -fno-ugly-assumed.
256 The meaning of this option is likely to be refined as future
258 versions of g77 provide more compatibility with other existing and
259 obsolete Fortran implementations.
260 -ff77
262 Specify that the program is written in idiomatic UNIX FORTRAN 77
263 and/or the dialect accepted by the f2c product. Same as
264 -fbackslash -fno-typeless-boz.
265 The meaning of this option is likely to be refined as future
267 versions of g77 provide more compatibility with other existing and
268 obsolete Fortran implementations.
269 -fno-f77
271 The -fno-f77 option is not the inverse of -ff77. It specifies that
272 the program is not written in idiomatic UNIX FORTRAN 77 or f2c but
273 in a more widely portable dialect. -fno-f77 is the same as
274 -fno-backslash.
275 The meaning of this option is likely to be refined as future
277 versions of g77 provide more compatibility with other existing and
278 obsolete Fortran implementations.
279 Options Controlling Fortran Dialect
281 The following options control the dialect of Fortran that the compiler
282 accepts:
283 -ffree-form
285 -fno-fixed-form
286 Specify that the source file is written in free form (introduced in
287 Fortran 90) instead of the more-traditional fixed form.
288 -ff90
290 Allow certain Fortran-90 constructs.
291 This option controls whether certain Fortran 90 constructs are
293 recognized. (Other Fortran 90 constructs might or might not be
294 recognized depending on other options such as -fvxt,
295 -ff90-intrinsics-enable, and the current level of support for
296 Fortran 90.)
297 -fvxt
299 Specify the treatment of certain constructs that have different
300 meanings depending on whether the code is written in GNU Fortran
301 (based on FORTRAN 77 and akin to Fortran 90) or VXT Fortran (more
302 like VAX FORTRAN).
303 The default is -fno-vxt. -fvxt specifies that the VXT Fortran
305 interpretations for those constructs are to be chosen.
306 -fdollar-ok
308 Allow $ as a valid character in a symbol name.
309 -fno-backslash
311 Specify that \ is not to be specially interpreted in character and
312 Hollerith constants a la C and many UNIX Fortran compilers.
313 For example, with -fbackslash in effect, A\nB specifies three
315 characters, with the second one being newline. With
316 -fno-backslash, it specifies four characters, A, \, n, and B.
317 Note that g77 implements a fairly general form of backslash
319 processing that is incompatible with the narrower forms supported
320 by some other compilers. For example, 'A\003B' is a three-
321 character string in g77 whereas other compilers that support
322 backslash might not support the three-octal-digit form, and thus
323 treat that string as longer than three characters.
324 -fno-ugly-args
326 Disallow passing Hollerith and typeless constants as actual
327 arguments (for example, CALL FOO(4HABCD)).
328 -fugly-assign
330 Use the same storage for a given variable regardless of whether it
331 is used to hold an assigned-statement label (as in ASSIGN 10 TO I)
332 or used to hold numeric data (as in I = 3).
333 -fugly-assumed
335 Assume any dummy array with a final dimension specified as 1 is
336 really an assumed-size array, as if * had been specified for the
337 final dimension instead of 1.
338 For example, DIMENSION X(1) is treated as if it had read DIMENSION
340 X(*).
341 -fugly-comma
343 In an external-procedure invocation, treat a trailing comma in the
344 argument list as specification of a trailing null argument, and
345 treat an empty argument list as specification of a single null
346 argument.
347 For example, CALL FOO(,) is treated as CALL FOO(%VAL(0), %VAL(0)).
349 That is, two null arguments are specified by the procedure call
350 when -fugly-comma is in force. And F = FUNC() is treated as F =
351 FUNC(%VAL(0)).
352 The default behavior, -fno-ugly-comma, is to ignore a single
354 trailing comma in an argument list. So, by default, CALL FOO(X,)
355 is treated exactly the same as CALL FOO(X).
356 -fugly-complex
358 Do not complain about REAL(expr) or AIMAG(expr) when expr is a
359 "COMPLEX" type other than "COMPLEX(KIND=1)"---usually this is used
360 to permit "COMPLEX(KIND=2)" ("DOUBLE COMPLEX") operands.
361 The -ff90 option controls the interpretation of this construct.
363 -fno-ugly-init
365 Disallow use of Hollerith and typeless constants as initial values
366 (in "PARAMETER" and "DATA" statements), and use of character
367 constants to initialize numeric types and vice versa.
368 For example, DATA I/'F'/, CHRVAR/65/, J/4HABCD/ is disallowed by
370 -fno-ugly-init.
371 -fugly-logint
373 Treat "INTEGER" and "LOGICAL" variables and expressions as
374 potential stand-ins for each other.
375 For example, automatic conversion between "INTEGER" and "LOGICAL"
377 is enabled, for many contexts, via this option.
378 -fonetrip
380 Executable iterative "DO" loops are to be executed at least once
381 each time they are reached.
382 ANSI FORTRAN 77 and more recent versions of the Fortran standard
384 specify that the body of an iterative "DO" loop is not executed if
385 the number of iterations calculated from the parameters of the loop
386 is less than 1. (For example, DO 10 I = 1, 0.) Such a loop is
387 called a zero-trip loop.
388 Prior to ANSI FORTRAN 77, many compilers implemented "DO" loops
390 such that the body of a loop would be executed at least once, even
391 if the iteration count was zero. Fortran code written assuming
392 this behavior is said to require one-trip loops. For example, some
393 code written to the FORTRAN 66 standard expects this behavior from
394 its "DO" loops, although that standard did not specify this
395 behavior.
396 The -fonetrip option specifies that the source file(s) being
398 compiled require one-trip loops.
399 This option affects only those loops specified by the (iterative)
401 "DO" statement and by implied-"DO" lists in I/O statements. Loops
402 specified by implied-"DO" lists in "DATA" and specification (non-
403 executable) statements are not affected.
404 -ftypeless-boz
406 Specifies that prefix-radix non-decimal constants, such as Z'ABCD',
407 are typeless instead of "INTEGER(KIND=1)".
408 You can test for yourself whether a particular compiler treats the
410 prefix form as "INTEGER(KIND=1)" or typeless by running the
411 following program:
412 EQUIVALENCE (I, R)
414 R = Z'ABCD1234'
415 J = Z'ABCD1234'
416 IF (J .EQ. I) PRINT *, 'Prefix form is TYPELESS'
417 IF (J .NE. I) PRINT *, 'Prefix form is INTEGER'
418 END
419 Reports indicate that many compilers process this form as
421 "INTEGER(KIND=1)", though a few as typeless, and at least one based
422 on a command-line option specifying some kind of compatibility.
423 -fintrin-case-initcap
425 -fintrin-case-upper
426 -fintrin-case-lower
427 -fintrin-case-any
428 Specify expected case for intrinsic names. -fintrin-case-lower is
429 the default.
430 -fmatch-case-initcap
432 -fmatch-case-upper
433 -fmatch-case-lower
434 -fmatch-case-any
435 Specify expected case for keywords. -fmatch-case-lower is the
436 default.
437 -fsource-case-upper
439 -fsource-case-lower
440 -fsource-case-preserve
441 Specify whether source text other than character and Hollerith
442 constants is to be translated to uppercase, to lowercase, or
443 preserved as is. -fsource-case-lower is the default.
444 -fsymbol-case-initcap
446 -fsymbol-case-upper
447 -fsymbol-case-lower
448 -fsymbol-case-any
449 Specify valid cases for user-defined symbol names.
450 -fsymbol-case-any is the default.
451 -fcase-strict-upper
453 Same as -fintrin-case-upper -fmatch-case-upper
454 -fsource-case-preserve -fsymbol-case-upper. (Requires all
455 pertinent source to be in uppercase.)
456 -fcase-strict-lower
458 Same as -fintrin-case-lower -fmatch-case-lower
459 -fsource-case-preserve -fsymbol-case-lower. (Requires all
460 pertinent source to be in lowercase.)
461 -fcase-initcap
463 Same as -fintrin-case-initcap -fmatch-case-initcap
464 -fsource-case-preserve -fsymbol-case-initcap. (Requires all
465 pertinent source to be in initial capitals, as in Print
466 *,SqRt(Value).)
467 -fcase-upper
469 Same as -fintrin-case-any -fmatch-case-any -fsource-case-upper
470 -fsymbol-case-any. (Maps all pertinent source to uppercase.)
471 -fcase-lower
473 Same as -fintrin-case-any -fmatch-case-any -fsource-case-lower
474 -fsymbol-case-any. (Maps all pertinent source to lowercase.)
475 -fcase-preserve
477 Same as -fintrin-case-any -fmatch-case-any -fsource-case-preserve
478 -fsymbol-case-any. (Preserves all case in user-defined symbols,
479 while allowing any-case matching of intrinsics and keywords. For
480 example, call Foo(i,I) would pass two different variables named i
481 and I to a procedure named Foo.)
482 -fbadu77-intrinsics-delete
484 -fbadu77-intrinsics-hide
485 -fbadu77-intrinsics-disable
486 -fbadu77-intrinsics-enable
487 Specify status of UNIX intrinsics having inappropriate forms.
488 -fbadu77-intrinsics-enable is the default.
489 -ff2c-intrinsics-delete
491 -ff2c-intrinsics-hide
492 -ff2c-intrinsics-disable
493 -ff2c-intrinsics-enable
494 Specify status of f2c-specific intrinsics. -ff2c-intrinsics-enable
495 is the default.
496 -ff90-intrinsics-delete
498 -ff90-intrinsics-hide
499 -ff90-intrinsics-disable
500 -ff90-intrinsics-enable
501 Specify status of F90-specific intrinsics. -ff90-intrinsics-enable
502 is the default.
503 -fgnu-intrinsics-delete
505 -fgnu-intrinsics-hide
506 -fgnu-intrinsics-disable
507 -fgnu-intrinsics-enable
508 Specify status of Digital's COMPLEX-related intrinsics.
509 -fgnu-intrinsics-enable is the default.
510 -fmil-intrinsics-delete
512 -fmil-intrinsics-hide
513 -fmil-intrinsics-disable
514 -fmil-intrinsics-enable
515 Specify status of MIL-STD-1753-specific intrinsics.
516 -fmil-intrinsics-enable is the default.
517 -funix-intrinsics-delete
519 -funix-intrinsics-hide
520 -funix-intrinsics-disable
521 -funix-intrinsics-enable
522 Specify status of UNIX intrinsics. -funix-intrinsics-enable is the
523 default.
524 -fvxt-intrinsics-delete
526 -fvxt-intrinsics-hide
527 -fvxt-intrinsics-disable
528 -fvxt-intrinsics-enable
529 Specify status of VXT intrinsics. -fvxt-intrinsics-enable is the
530 default.
531 -ffixed-line-length-n
533 Set column after which characters are ignored in typical fixed-form
534 lines in the source file, and through which spaces are assumed (as
535 if padded to that length) after the ends of short fixed-form lines.
536 Popular values for n include 72 (the standard and the default), 80
538 (card image), and 132 (corresponds to ``extended-source'' options
539 in some popular compilers). n may be none, meaning that the entire
540 line is meaningful and that continued character constants never
541 have implicit spaces appended to them to fill out the line.
542 -ffixed-line-length-0 means the same thing as
543 -ffixed-line-length-none.
544 Options to Request or Suppress Warnings
546 Warnings are diagnostic messages that report constructions which are
547 not inherently erroneous but which are risky or suggest there might
548 have been an error.
549 You can request many specific warnings with options beginning -W, for
551 example -Wimplicit to request warnings on implicit declarations. Each
552 of these specific warning options also has a negative form beginning
553 -Wno- to turn off warnings; for example, -Wno-implicit. This manual
554 lists only one of the two forms, whichever is not the default.
555 These options control the amount and kinds of warnings produced by GNU
557 Fortran:
558 -fsyntax-only
560 Check the code for syntax errors, but don't do anything beyond
561 that.
562 -pedantic
564 Issue warnings for uses of extensions to ANSI FORTRAN 77.
565 -pedantic also applies to C-language constructs where they occur in
566 GNU Fortran source files, such as use of \e in a character constant
567 within a directive like #include.
568 Valid ANSI FORTRAN 77 programs should compile properly with or
570 without this option. However, without this option, certain GNU
571 extensions and traditional Fortran features are supported as well.
572 With this option, many of them are rejected.
573 Some users try to use -pedantic to check programs for strict ANSI
575 conformance. They soon find that it does not do quite what they
576 want---it finds some non-ANSI practices, but not all. However,
577 improvements to g77 in this area are welcome.
578 -pedantic-errors
580 Like -pedantic, except that errors are produced rather than
581 warnings.
582 -fpedantic
584 Like -pedantic, but applies only to Fortran constructs.
585 -w Inhibit all warning messages.
587 -Wno-globals
589 Inhibit warnings about use of a name as both a global name (a
590 subroutine, function, or block data program unit, or a common
591 block) and implicitly as the name of an intrinsic in a source file.
592 Also inhibit warnings about inconsistent invocations and/or
594 definitions of global procedures (function and subroutines). Such
595 inconsistencies include different numbers of arguments and
596 different types of arguments.
597 -Wimplicit
599 Warn whenever a variable, array, or function is implicitly
600 declared. Has an effect similar to using the "IMPLICIT NONE"
601 statement in every program unit. (Some Fortran compilers provide
602 this feature by an option named -u or /WARNINGS=DECLARATIONS.)
603 -Wunused
605 Warn whenever a variable is unused aside from its declaration.
606 -Wuninitialized
608 Warn whenever an automatic variable is used without first being
609 initialized.
610 These warnings are possible only in optimizing compilation, because
612 they require data-flow information that is computed only when
613 optimizing. If you don't specify -O, you simply won't get these
614 warnings.
615 These warnings occur only for variables that are candidates for
617 register allocation. Therefore, they do not occur for a variable
618 whose address is taken, or whose size is other than 1, 2, 4 or 8
619 bytes. Also, they do not occur for arrays, even when they are in
620 registers.
621 Note that there might be no warning about a variable that is used
623 only to compute a value that itself is never used, because such
624 computations may be deleted by data-flow analysis before the
625 warnings are printed.
626 These warnings are made optional because GNU Fortran is not smart
628 enough to see all the reasons why the code might be correct despite
629 appearing to have an error. Here is one example of how this can
630 happen:
631 SUBROUTINE DISPAT(J)
633 IF (J.EQ.1) I=1
634 IF (J.EQ.2) I=4
635 IF (J.EQ.3) I=5
636 CALL FOO(I)
637 END
638 If the value of "J" is always 1, 2 or 3, then "I" is always
640 initialized, but GNU Fortran doesn't know this. Here is another
641 common case:
642 SUBROUTINE MAYBE(FLAG)
644 LOGICAL FLAG
645 IF (FLAG) VALUE = 9.4
646 ...
647 IF (FLAG) PRINT *, VALUE
648 END
649 This has no bug because "VALUE" is used only if it is set.
651 -Wall
653 The -Wunused and -Wuninitialized options combined. These are all
654 the options which pertain to usage that we recommend avoiding and
655 that we believe is easy to avoid. (As more warnings are added to
656 g77 some might be added to the list enabled by -Wall.)
657 The remaining -W... options are not implied by -Wall because they warn
659 about constructions that we consider reasonable to use, on occasion, in
660 clean programs.
661 -Wsurprising
663 Warn about ``suspicious'' constructs that are interpreted by the
664 compiler in a way that might well be surprising to someone reading
665 the code. These differences can result in subtle, compiler-
666 dependent (even machine-dependent) behavioral differences. The
667 constructs warned about include:
668 · Expressions having two arithmetic operators in a row, such as
670 X*-Y. Such a construct is nonstandard, and can produce
671 unexpected results in more complicated situations such as
672 X**-Y*Z. g77 along with many other compilers, interprets this
673 example differently than many programmers, and a few other
674 compilers. Specifically, g77 interprets X**-Y*Z as
675 (X**(-Y))*Z, while others might think it should be interpreted
676 as X**(-(Y*Z)).
677 A revealing example is the constant expression 2**-2*1., which
679 g77 evaluates to .25, while others might evaluate it to 0., the
680 difference resulting from the way precedence affects type
681 promotion.
682 (The -fpedantic option also warns about expressions having two
684 arithmetic operators in a row.)
685 · Expressions with a unary minus followed by an operand and then
687 a binary operator other than plus or minus. For example, -2**2
688 produces a warning, because the precedence is -(2**2), yielding
689 -4, not (-2)**2, which yields 4, and which might represent what
690 a programmer expects.
691 An example of an expression producing different results in a
693 surprising way is -I*S, where I holds the value -2147483648 and
694 S holds 0.5. On many systems, negating I results in the same
695 value, not a positive number, because it is already the lower
696 bound of what an "INTEGER(KIND=1)" variable can hold. So, the
697 expression evaluates to a positive number, while the
698 ``expected'' interpretation, (-I)*S, would evaluate to a
699 negative number.
700 Even cases such as -I*J produce warnings, even though, in most
702 configurations and situations, there is no computational
703 difference between the results of the two interpretations---the
704 purpose of this warning is to warn about differing
705 interpretations and encourage a better style of coding, not to
706 identify only those places where bugs might exist in the user's
707 code.
708 · "DO" loops with "DO" variables that are not of integral
710 type---that is, using "REAL" variables as loop control
711 variables. Although such loops can be written to work in the
712 ``obvious'' way, the way g77 is required by the Fortran
713 standard to interpret such code is likely to be quite different
714 from the way many programmers expect. (This is true of all
715 "DO" loops, but the differences are pronounced for non-integral
716 loop control variables.)
717 -Werror
719 Make all warnings into errors.
720 -W Turns on ``extra warnings'' and, if optimization is specified via
722 -O, the -Wuninitialized option. (This might change in future
723 versions of g77
724 ``Extra warnings'' are issued for:
726 · Unused parameters to a procedure (when -Wunused also is
728 specified).
729 · Overflows involving floating-point constants (not available for
731 certain configurations).
732 Some of these have no effect when compiling programs written in
734 Fortran:
735 -Wcomment
737 -Wformat
738 -Wparentheses
739 -Wswitch
740 -Wswitch-default
741 -Wswitch-enum
742 -Wtraditional
743 -Wshadow
744 -Wid-clash-len
745 -Wlarger-than-len
746 -Wconversion
747 -Waggregate-return
748 -Wredundant-decls
749 These options all could have some relevant meaning for GNU Fortran
750 programs, but are not yet supported.
751 Options for Debugging Your Program or GNU Fortran
753 GNU Fortran has various special options that are used for debugging
754 either your program or g77
755 -g Produce debugging information in the operating system's native
757 format (stabs, COFF, XCOFF, or DWARF). GDB can work with this
758 debugging information.
759 A sample debugging session looks like this (note the use of the
761 breakpoint):
762 $ cat gdb.f
764 PROGRAM PROG
765 DIMENSION A(10)
766 DATA A /1.,2.,3.,4.,5.,6.,7.,8.,9.,10./
767 A(5) = 4.
768 PRINT*,A
769 END
770 $ g77 -g -O gdb.f
771 $ gdb a.out
772 ...
773 (gdb) break MAIN__
774 Breakpoint 1 at 0x8048e96: file gdb.f, line 4.
775 (gdb) run
776 Starting program: /home/toon/g77-bugs/./a.out
777 Breakpoint 1, MAIN__ () at gdb.f:4
778 4 A(5) = 4.
779 Current language: auto; currently fortran
780 (gdb) print a(5)
781 $1 = 5
782 (gdb) step
783 5 PRINT*,A
784 (gdb) print a(5)
785 $2 = 4
786 ...
787 One could also add the setting of the breakpoint and the first run
789 command to the file .gdbinit in the current directory, to simplify
790 the debugging session.
791 Options That Control Optimization
793 Most Fortran users will want to use no optimization when developing and
794 testing programs, and use -O or -O2 when compiling programs for late-
795 cycle testing and for production use. However, note that certain
796 diagnostics---such as for uninitialized variables---depend on the flow
797 analysis done by -O, i.e. you must use -O or -O2 to get such
798 diagnostics.
799 The following flags have particular applicability when compiling
801 Fortran programs:
802 -malign-double
804 (Intel x86 architecture only.)
805 Noticeably improves performance of g77 programs making heavy use of
807 "REAL(KIND=2)" ("DOUBLE PRECISION") data on some systems. In
808 particular, systems using Pentium, Pentium Pro, 586, and 686
809 implementations of the i386 architecture execute programs faster
810 when "REAL(KIND=2)" ("DOUBLE PRECISION") data are aligned on 64-bit
811 boundaries in memory.
812 This option can, at least, make benchmark results more consistent
814 across various system configurations, versions of the program, and
815 data sets.
816 Note: The warning in the gcc documentation about this option does
818 not apply, generally speaking, to Fortran code compiled by g77
819 Also also note: The negative form of -malign-double is
821 -mno-align-double, not -benign-double.
822 -ffloat-store
824 Might help a Fortran program that depends on exact IEEE conformance
825 on some machines, but might slow down a program that doesn't.
826 This option is effective when the floating-point unit is set to
828 work in IEEE 854 `extended precision'---as it typically is on x86
829 and m68k GNU systems---rather than IEEE 754 double precision.
830 -ffloat-store tries to remove the extra precision by spilling data
831 from floating-point registers into memory and this typically
832 involves a big performance hit. However, it doesn't affect
833 intermediate results, so that it is only partially effective.
834 `Excess precision' is avoided in code like:
835 a = b + c
837 d = a * e
838 but not in code like:
840 d = (b + c) * e
842 For another, potentially better, way of controlling the precision,
844 see Floating-point precision.
845 -fforce-mem
847 -fforce-addr
848 Might improve optimization of loops.
849 -fno-inline
851 Don't compile statement functions inline. Might reduce the size of
852 a program unit---which might be at expense of some speed (though it
853 should compile faster). Note that if you are not optimizing, no
854 functions can be expanded inline.
855 -ffast-math
857 Might allow some programs designed to not be too dependent on IEEE
858 behavior for floating-point to run faster, or die trying. Sets
859 -funsafe-math-optimizations, -ffinite-math-only, and
860 -fno-trapping-math.
861 -funsafe-math-optimizations
863 Allow optimizations that may be give incorrect results for certain
864 IEEE inputs.
865 -ffinite-math-only
867 Allow optimizations for floating-point arithmetic that assume that
868 arguments and results are not NaNs or +-Infs.
869 This option should never be turned on by any -O option since it can
871 result in incorrect output for programs which depend on an exact
872 implementation of IEEE or ISO rules/specifications.
873 The default is -fno-finite-math-only.
875 -fno-trapping-math
877 Allow the compiler to assume that floating-point arithmetic will
878 not generate traps on any inputs. This is useful, for example,
879 when running a program using IEEE "non-stop" floating-point
880 arithmetic.
881 -fstrength-reduce
883 Might make some loops run faster.
884 -frerun-cse-after-loop
886 -fexpensive-optimizations
887 -fdelayed-branch
888 -fschedule-insns
889 -fschedule-insns2
890 -fcaller-saves
891 Might improve performance on some code.
892 -funroll-loops
894 Typically improves performance on code using iterative "DO" loops
895 by unrolling them and is probably generally appropriate for
896 Fortran, though it is not turned on at any optimization level.
897 Note that outer loop unrolling isn't done specifically; decisions
898 about whether to unroll a loop are made on the basis of its
899 instruction count.
900 Also, no `loop discovery'[1] is done, so only loops written with
902 "DO" benefit from loop optimizations, including---but not limited
903 to---unrolling. Loops written with "IF" and "GOTO" are not
904 currently recognized as such. This option unrolls only iterative
905 "DO" loops, not "DO WHILE" loops.
906 -funroll-all-loops
908 Probably improves performance on code using "DO WHILE" loops by
909 unrolling them in addition to iterative "DO" loops. In the absence
910 of "DO WHILE", this option is equivalent to -funroll-loops but
911 possibly slower.
912 -fno-move-all-movables
914 -fno-reduce-all-givs
915 -fno-rerun-loop-opt
916 In general, the optimizations enabled with these options will lead
917 to faster code being generated by GNU Fortran; hence they are
918 enabled by default when issuing the g77 command.
919 -fmove-all-movables and -freduce-all-givs will enable loop
921 optimization to move all loop-invariant index computations in
922 nested loops over multi-rank array dummy arguments out of these
923 loops.
924 -frerun-loop-opt will move offset calculations resulting from the
926 fact that Fortran arrays by default have a lower bound of 1 out of
927 the loops.
928 These three options are intended to be removed someday, once loop
930 optimization is sufficiently advanced to perform all those
931 transformations without help from these options.
932 Options Controlling the Preprocessor
934 These options control the C preprocessor, which is run on each C source
935 file before actual compilation.
936 Some of these options also affect how g77 processes the "INCLUDE"
938 directive. Since this directive is processed even when preprocessing
939 is not requested, it is not described in this section.
940 However, the "INCLUDE" directive does not apply preprocessing to the
942 contents of the included file itself.
943 Therefore, any file that contains preprocessor directives (such as
945 "#include", "#define", and "#if") must be included via the "#include"
946 directive, not via the "INCLUDE" directive. Therefore, any file
947 containing preprocessor directives, if included, is necessarily
948 included by a file that itself contains preprocessor directives.
949 Options for Directory Search
951 These options affect how the cpp preprocessor searches for files
952 specified via the "#include" directive. Therefore, when compiling
953 Fortran programs, they are meaningful when the preprocessor is used.
954 Some of these options also affect how g77 searches for files specified
956 via the "INCLUDE" directive, although files included by that directive
957 are not, themselves, preprocessed. These options are:
958 -I-
960 -Idir
961 These affect interpretation of the "INCLUDE" directive (as well as
962 of the "#include" directive of the cpp preprocessor).
963 Note that -Idir must be specified without any spaces between -I and
965 the directory name---that is, -Ifoo/bar is valid, but -I foo/bar is
966 rejected by the g77 compiler (though the preprocessor supports the
967 latter form). Also note that the general behavior of -I and
968 "INCLUDE" is pretty much the same as of -I with "#include" in the
969 cpp preprocessor, with regard to looking for header.gcc files and
970 other such things.
971 Options for Code Generation Conventions
973 These machine-independent options control the interface conventions
974 used in code generation.
975 Most of them have both positive and negative forms; the negative form
977 of -ffoo would be -fno-foo. In the table below, only one of the forms
978 is listed---the one which is not the default. You can figure out the
979 other form by either removing no- or adding it.
980 -fno-automatic
982 Treat each program unit as if the "SAVE" statement was specified
983 for every local variable and array referenced in it. Does not
984 affect common blocks. (Some Fortran compilers provide this option
985 under the name -static.)
986 -finit-local-zero
988 Specify that variables and arrays that are local to a program unit
989 (not in a common block and not passed as an argument) are to be
990 initialized to binary zeros.
991 Since there is a run-time penalty for initialization of variables
993 that are not given the "SAVE" attribute, it might be a good idea to
994 also use -fno-automatic with -finit-local-zero.
995 -fno-f2c
997 Do not generate code designed to be compatible with code generated
998 by f2c use the GNU calling conventions instead.
999 The f2c calling conventions require functions that return type
1001 "REAL(KIND=1)" to actually return the C type "double", and
1002 functions that return type "COMPLEX" to return the values via an
1003 extra argument in the calling sequence that points to where to
1004 store the return value. Under the GNU calling conventions, such
1005 functions simply return their results as they would in GNU
1006 C---"REAL(KIND=1)" functions return the C type "float", and
1007 "COMPLEX" functions return the GNU C type "complex" (or its
1008 "struct" equivalent).
1009 This does not affect the generation of code that interfaces with
1011 the "libg2c" library.
1012 However, because the "libg2c" library uses f2c calling conventions,
1014 g77 rejects attempts to pass intrinsics implemented by routines in
1015 this library as actual arguments when -fno-f2c is used, to avoid
1016 bugs when they are actually called by code expecting the GNU
1017 calling conventions to work.
1018 For example, INTRINSIC ABS;CALL FOO(ABS) is rejected when -fno-f2c
1020 is in force. (Future versions of the g77 run-time library might
1021 offer routines that provide GNU-callable versions of the routines
1022 that implement the f2c intrinsics that may be passed as actual
1023 arguments, so that valid programs need not be rejected when
1024 -fno-f2c is used.)
1025 Caution: If -fno-f2c is used when compiling any source file used in
1027 a program, it must be used when compiling all Fortran source files
1028 used in that program.
1029 -ff2c-library
1031 Specify that use of "libg2c" (or the original "libf2c") is
1032 required. This is the default for the current version of g77
1033 Currently it is not valid to specify -fno-f2c-library. This option
1035 is provided so users can specify it in shell scripts that build
1036 programs and libraries that require the "libf2c" library, even when
1037 being compiled by future versions of g77 that might otherwise
1038 default to generating code for an incompatible library.
1039 -fno-underscoring
1041 Do not transform names of entities specified in the Fortran source
1042 file by appending underscores to them.
1043 With -funderscoring in effect, g77 appends two underscores to names
1045 with underscores and one underscore to external names with no
1046 underscores. (g77 also appends two underscores to internal names
1047 with underscores to avoid naming collisions with external names.
1048 The -fno-second-underscore option disables appending of the second
1049 underscore in all cases.)
1050 This is done to ensure compatibility with code produced by many
1052 UNIX Fortran compilers, including f2c which perform the same
1053 transformations.
1054 Use of -fno-underscoring is not recommended unless you are
1056 experimenting with issues such as integration of (GNU) Fortran into
1057 existing system environments (vis-a-vis existing libraries, tools,
1058 and so on).
1059 For example, with -funderscoring, and assuming other defaults like
1061 -fcase-lower and that j() and max_count() are external functions
1062 while my_var and lvar are local variables, a statement like
1063 I = J() + MAX_COUNT (MY_VAR, LVAR)
1065 is implemented as something akin to:
1067 i = j_() + max_count__(&my_var__, &lvar);
1069 With -fno-underscoring, the same statement is implemented as:
1071 i = j() + max_count(&my_var, &lvar);
1073 Use of -fno-underscoring allows direct specification of user-
1075 defined names while debugging and when interfacing g77 code with
1076 other languages.
1077 Note that just because the names match does not mean that the
1079 interface implemented by g77 for an external name matches the
1080 interface implemented by some other language for that same name.
1081 That is, getting code produced by g77 to link to code produced by
1082 some other compiler using this or any other method can be only a
1083 small part of the overall solution---getting the code generated by
1084 both compilers to agree on issues other than naming can require
1085 significant effort, and, unlike naming disagreements, linkers
1086 normally cannot detect disagreements in these other areas.
1087 Also, note that with -fno-underscoring, the lack of appended
1089 underscores introduces the very real possibility that a user-
1090 defined external name will conflict with a name in a system
1091 library, which could make finding unresolved-reference bugs quite
1092 difficult in some cases---they might occur at program run time, and
1093 show up only as buggy behavior at run time.
1094 In future versions of g77 we hope to improve naming and linking
1096 issues so that debugging always involves using the names as they
1097 appear in the source, even if the names as seen by the linker are
1098 mangled to prevent accidental linking between procedures with
1099 incompatible interfaces.
1100 -fno-second-underscore
1102 Do not append a second underscore to names of entities specified in
1103 the Fortran source file.
1104 This option has no effect if -fno-underscoring is in effect.
1106 Otherwise, with this option, an external name such as MAX_COUNT is
1108 implemented as a reference to the link-time external symbol
1109 max_count_, instead of max_count__.
1110 -fno-ident
1112 Ignore the #ident directive.
1113 -fzeros
1115 Treat initial values of zero as if they were any other value.
1116 As of version 0.5.18, g77 normally treats "DATA" and other
1118 statements that are used to specify initial values of zero for
1119 variables and arrays as if no values were actually specified, in
1120 the sense that no diagnostics regarding multiple initializations
1121 are produced.
1122 This is done to speed up compiling of programs that initialize
1124 large arrays to zeros.
1125 Use -fzeros to revert to the simpler, slower behavior that can
1127 catch multiple initializations by keeping track of all
1128 initializations, zero or otherwise.
1129 Caution: Future versions of g77 might disregard this option (and
1131 its negative form, the default) or interpret it somewhat
1132 differently. The interpretation changes will affect only non-
1133 standard programs; standard-conforming programs should not be
1134 affected.
1135 -femulate-complex
1137 Implement "COMPLEX" arithmetic via emulation, instead of using the
1138 facilities of the gcc back end that provide direct support of
1139 "complex" arithmetic.
1140 (gcc had some bugs in its back-end support for "complex"
1142 arithmetic, due primarily to the support not being completed as of
1143 version 2.8.1 and "egcs" 1.1.2.)
1144 Use -femulate-complex if you suspect code-generation bugs, or
1146 experience compiler crashes, that might result from g77 using the
1147 "COMPLEX" support in the gcc back end. If using that option fixes
1148 the bugs or crashes you are seeing, that indicates a likely g77
1149 bugs (though, all compiler crashes are considered bugs), so, please
1150 report it. (Note that the known bugs, now believed fixed, produced
1151 compiler crashes rather than causing the generation of incorrect
1152 code.)
1153 Use of this option should not affect how Fortran code compiled by
1155 g77 works in terms of its interfaces to other code, e.g. that
1156 compiled by f2c
1157 As of GCC version 3.0, this option is not necessary anymore.
1159 Caution: Future versions of g77 might ignore both forms of this
1161 option.
1162 -falias-check
1164 -fargument-alias
1165 -fargument-noalias
1166 -fno-argument-noalias-global
1167 Version info: These options are not supported by versions of g77
1168 based on gcc version 2.8.
1169 These options specify to what degree aliasing (overlap) is
1171 permitted between arguments (passed as pointers) and "COMMON"
1172 (external, or public) storage.
1173 The default for Fortran code, as mandated by the FORTRAN 77 and
1175 Fortran 90 standards, is -fargument-noalias-global. The default
1176 for code written in the C language family is -fargument-alias.
1177 Note that, on some systems, compiling with -fforce-addr in effect
1179 can produce more optimal code when the default aliasing options are
1180 in effect (and when optimization is enabled).
1181 -fno-globals
1183 Disable diagnostics about inter-procedural analysis problems, such
1184 as disagreements about the type of a function or a procedure's
1185 argument, that might cause a compiler crash when attempting to
1186 inline a reference to a procedure within a program unit. (The
1187 diagnostics themselves are still produced, but as warnings, unless
1188 -Wno-globals is specified, in which case no relevant diagnostics
1189 are produced.)
1190 Further, this option disables such inlining, to avoid compiler
1192 crashes resulting from incorrect code that would otherwise be
1193 diagnosed.
1194 As such, this option might be quite useful when compiling existing,
1196 ``working'' code that happens to have a few bugs that do not
1197 generally show themselves, but which g77 diagnoses.
1198 Use of this option therefore has the effect of instructing g77 to
1200 behave more like it did up through version 0.5.19.1, when it paid
1201 little or no attention to disagreements between program units about
1202 a procedure's type and argument information, and when it performed
1203 no inlining of procedures (except statement functions).
1204 Without this option, g77 defaults to performing the potentially
1206 inlining procedures as it started doing in version 0.5.20, but as
1207 of version 0.5.21, it also diagnoses disagreements that might cause
1208 such inlining to crash the compiler as (fatal) errors, and warns
1209 about similar disagreements that are currently believed to not
1210 likely to result in the compiler later crashing or producing
1211 incorrect code.
1212 -fflatten-arrays
1214 Use back end's C-like constructs (pointer plus offset) instead of
1215 its "ARRAY_REF" construct to handle all array references.
1216 Note: This option is not supported. It is intended for use only by
1218 g77 developers, to evaluate code-generation issues. It might be
1219 removed at any time.
1220 -fbounds-check
1222 -ffortran-bounds-check
1223 Enable generation of run-time checks for array subscripts and
1224 substring start and end points against the (locally) declared
1225 minimum and maximum values.
1226 The current implementation uses the "libf2c" library routine
1228 "s_rnge" to print the diagnostic.
1229 However, whereas f2c generates a single check per reference for a
1231 multi-dimensional array, of the computed offset against the valid
1232 offset range (0 through the size of the array), g77 generates a
1233 single check per subscript expression. This catches some cases of
1234 potential bugs that f2c does not, such as references to below the
1235 beginning of an assumed-size array.
1236 g77 also generates checks for "CHARACTER" substring references,
1238 something f2c currently does not do.
1239 Use the new -ffortran-bounds-check option to specify bounds-
1241 checking for only the Fortran code you are compiling, not
1242 necessarily for code written in other languages.
1243 Note: To provide more detailed information on the offending
1245 subscript, g77 provides the "libg2c" run-time library routine
1246 "s_rnge" with somewhat differently-formatted information. Here's a
1247 sample diagnostic:
1248 Subscript out of range on file line 4, procedure rnge.f/bf.
1250 Attempt to access the -6-th element of variable b[subscript-2-of-2].
1251 Aborted
1252 The above message indicates that the offending source line is line
1254 4 of the file rnge.f, within the program unit (or statement
1255 function) named bf. The offended array is named b. The offended
1256 array dimension is the second for a two-dimensional array, and the
1257 offending, computed subscript expression was -6.
1258 For a "CHARACTER" substring reference, the second line has this
1260 appearance:
1261 Attempt to access the 11-th element of variable a[start-substring].
1263 This indicates that the offended "CHARACTER" variable or array is
1265 named a, the offended substring position is the starting (leftmost)
1266 position, and the offending substring expression is 11.
1267 (Though the verbage of "s_rnge" is not ideal for the purpose of the
1269 g77 compiler, the above information should provide adequate
1270 diagnostic abilities to it users.)
1271 Some of these do not work when compiling programs written in Fortran:
1273 -fpcc-struct-return
1275 -freg-struct-return
1276 You should not use these except strictly the same way as you used
1277 them to build the version of "libg2c" with which you will be
1278 linking all code compiled by g77 with the same option.
1279 -fshort-double
1281 This probably either has no effect on Fortran programs, or makes
1282 them act loopy.
1283 -fno-common
1285 Do not use this when compiling Fortran programs, or there will be
1286 Trouble.
1287 -fpack-struct
1289 This probably will break any calls to the "libg2c" library, at the
1290 very least, even if it is built with the same option.
1291
1293 GNU Fortran currently does not make use of any environment variables to
1294 control its operation above and beyond those that affect the operation
1295 of gcc.
1296
1298 For instructions on reporting bugs, see <http://gcc.gnu.org/bugs.html>.
1299 Use of the gccbug script to report bugs is recommended.
1300
1302 1. loop discovery refers to the process by which a compiler, or indeed
1303 any reader of a program, determines which portions of the program
1304 are more likely to be executed repeatedly as it is being run. Such
1305 discovery typically is done early when compiling using optimization
1306 techniques, so the ``discovered'' loops get more attention---and
1307 more run-time resources, such as registers---from the compiler. It
1308 is easy to ``discover'' loops that are constructed out of looping
1309 constructs in the language (such as Fortran's "DO"). For some
1310 programs, ``discovering'' loops constructed out of lower-level
1311 constructs (such as "IF" and "GOTO") can lead to generation of more
1312 optimal code than otherwise.
1313
1315 gpl(7), gfdl(7), fsf-funding(7), cpp(1), gcov(1), gcc(1), as(1), ld(1),
1316 gdb(1), adb(1), dbx(1), sdb(1) and the Info entries for gcc, cpp, g77,
1317 as, ld, binutils and gdb.
1318
1320 See the Info entry for g77 for contributors to GCC and G77.
1321
1323 Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2004 Free
1324 Software Foundation, Inc.
1325 Permission is granted to copy, distribute and/or modify this document
1327 under the terms of the GNU Free Documentation License, Version 1.2 or
1328 any later version published by the Free Software Foundation; with the
1329 Invariant Sections being ``GNU General Public License'' and ``Funding
1330 Free Software'', the Front-Cover texts being (a) (see below), and with
1331 the Back-Cover Texts being (b) (see below). A copy of the license is
1332 included in the gfdl(7) man page.
1333 (a) The FSF's Front-Cover Text is:
1335 A GNU Manual
1337 (b) The FSF's Back-Cover Text is:
1339 You have freedom to copy and modify this GNU Manual, like GNU
1341 software. Copies published by the Free Software Foundation raise
1342 funds for GNU development.
1343gcc-3.4.6 2018-02-08 G77(1)