symtab.c (change_decl_assembler_name): Fix transparent alias chain construction.
[gcc.git] / gcc / common.opt
1 ; Options for the language- and target-independent parts of the compiler.
2
3 ; Copyright (C) 2003-2014 Free Software Foundation, Inc.
4 ;
5 ; This file is part of GCC.
6 ;
7 ; GCC is free software; you can redistribute it and/or modify it under
8 ; the terms of the GNU General Public License as published by the Free
9 ; Software Foundation; either version 3, or (at your option) any later
10 ; version.
11 ;
12 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 ; for more details.
16 ;
17 ; You should have received a copy of the GNU General Public License
18 ; along with GCC; see the file COPYING3. If not see
19 ; <http://www.gnu.org/licenses/>.
20
21 ; See the GCC internals manual (options.texi) for a description of this file's format.
22
23 ; Please try to keep this file in ASCII collating order.
24
25 Variable
26 int target_flags
27
28 Variable
29 int optimize
30
31 Variable
32 int optimize_size
33
34 Variable
35 int optimize_debug
36
37 ; Not used directly to control optimizations, only to save -Ofast
38 ; setting for "optimize" attributes.
39 Variable
40 int optimize_fast
41
42 ; True if this is the lto front end. This is used to disable gimple
43 ; generation and lowering passes that are normally run on the output
44 ; of a front end. These passes must be bypassed for lto since they
45 ; have already been done before the gimple was written.
46 Variable
47 bool in_lto_p = false
48
49 ; 0 means straightforward implementation of complex divide acceptable.
50 ; 1 means wide ranges of inputs must work for complex divide.
51 ; 2 means C99-like requirements for complex multiply and divide.
52 Variable
53 int flag_complex_method = 1
54
55 ; Nonzero if subexpressions must be evaluated from left-to-right.
56 Variable
57 int flag_evaluation_order = 0
58
59 ; Language specific warning pass for unused results.
60 Variable
61 bool flag_warn_unused_result = false
62
63 Variable
64 int *param_values
65
66 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
67 Variable
68 int flag_generate_lto
69
70 ; True to warn about any objects definitions whose size is larger
71 ; than N bytes. Also want about function definitions whose returned
72 ; values are larger than N bytes, where N is 'larger_than_size'.
73 Variable
74 bool warn_larger_than
75
76 Variable
77 HOST_WIDE_INT larger_than_size
78
79 ; True to warn about any function whose frame size is larger
80 ; than N bytes.
81 Variable
82 bool warn_frame_larger_than
83
84 Variable
85 HOST_WIDE_INT frame_larger_than_size
86
87 ; Nonzero means we should be saving declaration info into a .X file.
88 Variable
89 int flag_gen_aux_info = 0
90
91 ; Nonzero if we are compiling code for a shared library, zero for
92 ; executable.
93 Variable
94 int flag_shlib
95
96 ; These two are really VEC(char_p,heap) *.
97
98 Variable
99 void *flag_instrument_functions_exclude_functions
100
101 Variable
102 void *flag_instrument_functions_exclude_files
103
104 ; Generic structs (e.g. templates not explicitly specialized)
105 ; may not have a compilation unit associated with them, and so
106 ; may need to be treated differently from ordinary structs.
107 ;
108 ; Structs only handled by reference (indirectly), will also usually
109 ; not need as much debugging information.
110
111 Variable
112 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
113
114 Variable
115 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
116
117 ; True if we should exit after parsing options.
118 Variable
119 bool exit_after_options
120
121 ; Type(s) of debugging information we are producing (if any). See
122 ; flag-types.h for the definitions of the different possible types of
123 ; debugging information.
124 Variable
125 enum debug_info_type write_symbols = NO_DEBUG
126
127 ; Level of debugging information we are producing. See flag-types.h
128 ; for the definitions of the different possible levels.
129 Variable
130 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
131
132 ; Nonzero means use GNU-only extensions in the generated symbolic
133 ; debugging information. Currently, this only has an effect when
134 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
135 Variable
136 bool use_gnu_debug_info_extensions
137
138 ; Original value of maximum field alignment in bytes, specified via
139 ; -fpack-struct=<value>.
140 Variable
141 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
142
143 ; Type of stack check.
144 Variable
145 enum stack_check_type flag_stack_check = NO_STACK_CHECK
146
147 ; True if stack usage information needs to be computed.
148 Variable
149 bool flag_stack_usage_info = false
150
151 ; -dA causes debug commentary information to be produced in
152 ; the generated assembly code (to make it more readable). This option
153 ; is generally only of use to those who actually need to read the
154 ; generated assembly code (perhaps while debugging the compiler itself).
155 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
156 ; to be a catchall for printing debug information in the assembler file.
157 Variable
158 int flag_debug_asm
159
160 ; -dP causes the rtl to be emitted as a comment in assembly.
161 Variable
162 int flag_dump_rtl_in_asm
163
164 ; Whether -da was passed (used only in handle_common_deferred_options).
165 Variable
166 bool flag_dump_all_passed
167
168 ; Other flags saying which kinds of debugging dump have been requested.
169
170 Variable
171 int rtl_dump_and_exit
172
173 Variable
174 int flag_print_asm_name
175
176 ; Name of top-level original source file (what was input to cpp).
177 ; This comes from the #-command at the beginning of the actual input.
178 ; If there isn't any there, then this is the cc1 input file name.
179 Variable
180 const char *main_input_filename
181
182 ; Pointer to base name in main_input_filename, with directories and a
183 ; single final extension removed, and the length of this base
184 ; name.
185
186 Variable
187 const char *main_input_basename
188
189 Variable
190 int main_input_baselength
191
192 ; Which options have been printed by --help.
193 Variable
194 char *help_printed
195
196 ; Which enums have been printed by --help. 0 = not printed, no
197 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
198 ; = printed.
199 Variable
200 char *help_enum_printed
201
202 ; The number of columns for --help output.
203 Variable
204 unsigned int help_columns
205
206 ; Whether this options structure has been through finish_options
207 Variable
208 bool flag_opts_finished
209
210 ; What the sanitizer should instrument
211 Variable
212 unsigned int flag_sanitize
213
214 ; Flag whether a prefix has been added to dump_base_name
215 Variable
216 bool dump_base_name_prefixed = false
217
218 ###
219 Driver
220
221 -assemble
222 Driver Alias(S)
223
224 -compile
225 Driver Alias(c)
226
227 -coverage
228 Driver Alias(coverage)
229
230 -debug
231 Common Alias(g)
232
233 -dump
234 Common Separate Alias(d)
235
236 -dump=
237 Common Joined Alias(d)
238
239 -dumpbase
240 Common Separate Alias(dumpbase)
241
242 -dumpdir
243 Common Separate Alias(dumpdir)
244
245 -entry
246 Driver Separate Alias(e)
247
248 -entry=
249 Driver Joined Alias(e)
250
251 -extra-warnings
252 Common Warning Alias(Wextra)
253
254 -for-assembler
255 Driver Separate Alias(Xassembler)
256
257 -for-assembler=
258 Driver JoinedOrMissing Alias(Xassembler)
259
260 -for-linker
261 Driver Separate Alias(Xlinker)
262
263 -for-linker=
264 Driver JoinedOrMissing Alias(Xlinker)
265
266 -force-link
267 Driver Separate Alias(u)
268
269 -force-link=
270 Driver Joined Alias(u)
271
272 -help
273 Common Driver Var(help_flag)
274 Display this information
275
276 -help=
277 Common Driver Report Joined
278 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
279
280 -language
281 Driver Separate Alias(x)
282
283 -language=
284 Driver Joined Alias(x)
285
286 -library-directory
287 Driver Separate Alias(L)
288
289 -library-directory=
290 Driver Joined Alias(L)
291
292 -no-canonical-prefixes
293 Driver Alias(no-canonical-prefixes)
294
295 -no-standard-libraries
296 Driver Alias(nostdlib)
297
298 -no-sysroot-suffix
299 Driver Var(no_sysroot_suffix)
300
301 -no-warnings
302 Common Alias(w)
303
304 -optimize
305 Common Alias(O)
306
307 -output
308 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
309
310 -output=
311 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
312
313 -pass-exit-codes
314 Driver Alias(pass-exit-codes)
315
316 -pedantic
317 Common Alias(Wpedantic)
318
319 -pedantic-errors
320 Common Alias(pedantic-errors)
321
322 -pie
323 Driver Alias(pie)
324
325 -pipe
326 Driver Alias(pipe)
327
328 -prefix
329 Driver Separate Alias(B)
330
331 -prefix=
332 Driver JoinedOrMissing Alias(B)
333
334 -preprocess
335 Driver Alias(E)
336
337 -print-file-name
338 Driver Separate Alias(print-file-name=)
339
340 -print-file-name=
341 Driver JoinedOrMissing Alias(print-file-name=)
342
343 -print-libgcc-file-name
344 Driver Alias(print-libgcc-file-name)
345
346 -print-multi-directory
347 Driver Alias(print-multi-directory)
348
349 -print-multi-lib
350 Driver Alias(print-multi-lib)
351
352 -print-multi-os-directory
353 Driver Alias(print-multi-os-directory)
354
355 -print-multiarch
356 Driver Alias(print-multiarch)
357
358 -print-prog-name
359 Driver Separate Alias(print-prog-name=)
360
361 -print-prog-name=
362 Driver JoinedOrMissing Alias(print-prog-name=)
363
364 -print-search-dirs
365 Driver Alias(print-search-dirs)
366
367 -print-sysroot
368 Driver Alias(print-sysroot)
369
370 -print-sysroot-headers-suffix
371 Driver Alias(print-sysroot-headers-suffix)
372
373 -profile
374 Common Alias(p)
375
376 -save-temps
377 Driver Alias(save-temps)
378
379 -shared
380 Driver Alias(shared)
381
382 -specs
383 Driver Separate Alias(specs=)
384
385 -specs=
386 Driver Joined Alias(specs=)
387
388 -static
389 Driver Alias(static)
390
391 -symbolic
392 Driver Alias(symbolic)
393
394 -target-help
395 Common Driver
396 Alias for --help=target
397
398 -time
399 Driver Alias(time)
400
401 -verbose
402 Driver Alias(v)
403
404 ;; The driver used to convert options such as --help into forms such
405 ;; as -fhelp; the following four entries are for compatibility with
406 ;; any direct uses of those (undocumented) -f forms
407 fhelp
408 Common Driver Alias(-help)
409
410 fhelp=
411 Common Driver Joined Alias(-help=)
412
413 ftarget-help
414 Common Driver Alias(-target-help)
415
416 fversion
417 Common Driver Alias(-version)
418
419 -param
420 Common Separate
421 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
422
423 -param=
424 Common Joined Alias(-param)
425
426 -sysroot
427 Driver Separate Alias(-sysroot=)
428
429 -sysroot=
430 Driver JoinedOrMissing
431
432 -version
433 Common Driver
434
435 B
436 Driver Joined Separate
437
438 E
439 Driver
440
441 L
442 Driver Joined Separate
443
444 N
445 Driver
446
447 O
448 Common JoinedOrMissing Optimization
449 -O<number> Set optimization level to <number>
450
451 Os
452 Common Optimization
453 Optimize for space rather than speed
454
455 Ofast
456 Common Optimization
457 Optimize for speed disregarding exact standards compliance
458
459 Og
460 Common Optimization
461 Optimize for debugging experience rather than speed or size
462
463 Q
464 Driver
465
466 Qn
467 Driver Negative(Qy)
468
469 Qy
470 Driver Negative(Qn)
471
472 R
473 Driver Joined Separate
474
475 S
476 Driver
477
478 T
479 Driver Joined Separate
480
481 Tbss
482 Driver Separate
483
484 Tbss=
485 Driver Joined
486
487 Tdata
488 Driver Separate
489
490 Tdata=
491 Driver Joined
492
493 Ttext
494 Driver Separate
495
496 Ttext=
497 Driver Joined
498
499 W
500 Common RejectNegative Warning Alias(Wextra)
501 This switch is deprecated; use -Wextra instead
502
503 Wa,
504 Driver JoinedOrMissing
505
506 Wl,
507 Driver JoinedOrMissing
508
509 Wp,
510 Driver JoinedOrMissing
511
512 Waggregate-return
513 Common Var(warn_aggregate_return) Warning
514 Warn about returning structures, unions or arrays
515
516 Waggressive-loop-optimizations
517 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
518 Warn if a loop with constant number of iterations triggers undefined behavior
519
520 Warray-bounds
521 Common Var(warn_array_bounds) Warning
522 Warn if an array is accessed out of bounds
523
524 Wattributes
525 Common Var(warn_attributes) Init(1) Warning
526 Warn about inappropriate attribute usage
527
528 Wcast-align
529 Common Var(warn_cast_align) Warning
530 Warn about pointer casts which increase alignment
531
532 Wcpp
533 Common Var(warn_cpp) Init(1) Warning
534 Warn when a #warning directive is encountered
535
536 Wdeprecated-declarations
537 Common Var(warn_deprecated_decl) Init(1) Warning
538 Warn about uses of __attribute__((deprecated)) declarations
539
540 Wdisabled-optimization
541 Common Var(warn_disabled_optimization) Warning
542 Warn when an optimization pass is disabled
543
544 Werror
545 Common Var(warnings_are_errors)
546 Treat all warnings as errors
547
548 Werror=
549 Common Joined
550 Treat specified warning as error
551
552 Wextra
553 Common Var(extra_warnings) Warning
554 Print extra (possibly unwanted) warnings
555
556 Wfatal-errors
557 Common Var(flag_fatal_errors)
558 Exit on the first error occurred
559
560 Wframe-larger-than=
561 Common RejectNegative Joined UInteger
562 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
563
564 Wfree-nonheap-object
565 Common Var(warn_free_nonheap_object) Init(1) Warning
566 Warn when attempting to free a non-heap object
567
568 Winline
569 Common Var(warn_inline) Warning
570 Warn when an inlined function cannot be inlined
571
572 Winvalid-memory-model
573 Common Var(warn_invalid_memory_model) Init(1) Warning
574 Warn when an atomic memory model parameter is known to be outside the valid range.
575
576 Wlarger-than-
577 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
578
579 Wlarger-than=
580 Common RejectNegative Joined UInteger Warning
581 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
582
583 Wunsafe-loop-optimizations
584 Common Var(warn_unsafe_loop_optimizations) Warning
585 Warn if the loop cannot be optimized due to nontrivial assumptions.
586
587 Wmissing-noreturn
588 Common Alias(Wsuggest-attribute=noreturn)
589
590 Woverflow
591 Common Var(warn_overflow) Init(1) Warning
592 Warn about overflow in arithmetic expressions
593
594 Wpacked
595 Common Var(warn_packed) Warning
596 Warn when the packed attribute has no effect on struct layout
597
598 Wpadded
599 Common Var(warn_padded) Warning
600 Warn when padding is required to align structure members
601
602 Wpedantic
603 Common Var(pedantic) Warning
604 Issue warnings needed for strict compliance to the standard
605
606 Wshadow
607 Common Var(warn_shadow) Warning
608 Warn when one local variable shadows another
609
610 Wstack-protector
611 Common Var(warn_stack_protect) Warning
612 Warn when not issuing stack smashing protection for some reason
613
614 Wstack-usage=
615 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
616 Warn if stack usage might be larger than specified amount
617
618 Wstrict-aliasing
619 Common Warning
620 Warn about code which might break strict aliasing rules
621
622 Wstrict-aliasing=
623 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
624 Warn about code which might break strict aliasing rules
625
626 Wstrict-overflow
627 Common Warning
628 Warn about optimizations that assume that signed overflow is undefined
629
630 Wstrict-overflow=
631 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
632 Warn about optimizations that assume that signed overflow is undefined
633
634 Wsuggest-attribute=const
635 Common Var(warn_suggest_attribute_const) Warning
636 Warn about functions which might be candidates for __attribute__((const))
637
638 Wsuggest-attribute=pure
639 Common Var(warn_suggest_attribute_pure) Warning
640 Warn about functions which might be candidates for __attribute__((pure))
641
642 Wsuggest-attribute=noreturn
643 Common Var(warn_suggest_attribute_noreturn) Warning
644 Warn about functions which might be candidates for __attribute__((noreturn))
645
646 Wsystem-headers
647 Common Var(warn_system_headers) Warning
648 Do not suppress warnings from system headers
649
650 Wtrampolines
651 Common Var(warn_trampolines) Warning
652 Warn whenever a trampoline is generated
653
654 Wtype-limits
655 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
656 Warn if a comparison is always true or always false due to the limited range of the data type
657
658 Wuninitialized
659 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
660 Warn about uninitialized automatic variables
661
662 Wmaybe-uninitialized
663 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
664 Warn about maybe uninitialized automatic variables
665
666 Wunreachable-code
667 Common Ignore
668 Does nothing. Preserved for backward compatibility.
669
670 Wunused
671 Common Var(warn_unused) Init(0) Warning
672 Enable all -Wunused- warnings
673
674 Wunused-but-set-parameter
675 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
676 Warn when a function parameter is only set, otherwise unused
677
678 Wunused-but-set-variable
679 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
680 Warn when a variable is only set, otherwise unused
681
682 Wunused-function
683 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
684 Warn when a function is unused
685
686 Wunused-label
687 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
688 Warn when a label is unused
689
690 Wunused-parameter
691 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
692 Warn when a function parameter is unused
693
694 Wunused-value
695 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
696 Warn when an expression value is unused
697
698 Wunused-variable
699 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
700 Warn when a variable is unused
701
702 Wcoverage-mismatch
703 Common Var(warn_coverage_mismatch) Init(1) Warning
704 Warn in case profiles in -fprofile-use do not match
705
706 Wvector-operation-performance
707 Common Var(warn_vector_operation_performance) Warning
708 Warn when a vector operation is compiled outside the SIMD
709
710 Xassembler
711 Driver Separate
712
713 Xlinker
714 Driver Separate
715
716 Xpreprocessor
717 Driver Separate
718
719 Z
720 Driver
721
722 aux-info
723 Common Separate Var(aux_info_file_name)
724 -aux-info <file> Emit declaration information into <file>
725
726 aux-info=
727 Common Joined Alias(aux-info)
728
729 auxbase
730 Common Separate RejectDriver Var(aux_base_name)
731
732 auxbase-strip
733 Common Separate RejectDriver
734
735 coverage
736 Driver
737
738 c
739 Driver
740
741 d
742 Common Joined
743 -d<letters> Enable dumps from specific passes of the compiler
744
745 dumpbase
746 Common Separate Var(dump_base_name)
747 -dumpbase <file> Set the file basename to be used for dumps
748
749 dumpdir
750 Common Separate Var(dump_dir_name)
751 -dumpdir <dir> Set the directory name to be used for dumps
752
753 dumpmachine
754 Driver
755
756 dumpspecs
757 Driver
758
759 dumpversion
760 Driver
761
762 e
763 Driver Joined Separate
764
765 ; This option has historically been passed down to the linker by an
766 ; accident of a %{e*} spec, so ensure it continues to be passed down
767 ; as a single option. The supported option for this purpose is
768 ; -rdynamic. See PR 47390.
769 export-dynamic
770 Driver Undocumented
771
772 ; The version of the C++ ABI in use. The following values are allowed:
773 ;
774 ; 0: The version of the ABI believed most conformant with the C++ ABI
775 ; specification. This ABI may change as bugs are discovered and fixed.
776 ; Therefore, 0 will not necessarily indicate the same ABI in different
777 ; versions of G++.
778 ;
779 ; 1: The version of the ABI first used in G++ 3.2.
780 ;
781 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
782 ;
783 ; 3: The version of the ABI that fixes the missing underscore
784 ; in template non-type arguments of pointer type.
785 ;
786 ; 4: The version of the ABI that introduces unambiguous mangling of
787 ; vector types. First selectable in G++ 4.5.
788 ;
789 ; 5: The version of the ABI that ignores attribute const/noreturn
790 ; in function pointer mangling, and corrects mangling of decltype and
791 ; function parameters used in other parameters and the return type.
792 ; First selectable in G++ 4.6.
793 ;
794 ; 6: The version of the ABI that doesn't promote scoped enums to int and
795 ; changes the mangling of template argument packs, const/static_cast,
796 ; prefix ++ and --, and a class scope function used as a template
797 ; argument.
798 ; First selectable in G++ 4.7.
799 ;
800 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
801 ; corrects the mangling of lambdas in default argument scope.
802 ; First selectable in G++ 4.8.
803 ;
804 ; 8: The version of the ABI that corrects the substitution behavior of
805 ; function types with function-cv-qualifiers.
806 ; First selectable in G++ 4.9.
807 ;
808 ; Additional positive integers will be assigned as new versions of
809 ; the ABI become the default version of the ABI.
810 fabi-version=
811 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
812
813 faggressive-loop-optimizations
814 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
815 Aggressively optimize loops using language constraints
816
817 falign-functions
818 Common Report Var(align_functions,0) Optimization UInteger
819 Align the start of functions
820
821 falign-functions=
822 Common RejectNegative Joined UInteger Var(align_functions)
823
824 falign-jumps
825 Common Report Var(align_jumps,0) Optimization UInteger
826 Align labels which are only reached by jumping
827
828 falign-jumps=
829 Common RejectNegative Joined UInteger Var(align_jumps)
830
831 falign-labels
832 Common Report Var(align_labels,0) Optimization UInteger
833 Align all labels
834
835 falign-labels=
836 Common RejectNegative Joined UInteger Var(align_labels)
837
838 falign-loops
839 Common Report Var(align_loops,0) Optimization UInteger
840 Align the start of loops
841
842 falign-loops=
843 Common RejectNegative Joined UInteger Var(align_loops)
844
845 fargument-alias
846 Common Ignore
847 Does nothing. Preserved for backward compatibility.
848
849 fargument-noalias
850 Common Ignore
851 Does nothing. Preserved for backward compatibility.
852
853 fargument-noalias-global
854 Common Ignore
855 Does nothing. Preserved for backward compatibility.
856
857 fargument-noalias-anything
858 Common Ignore
859 Does nothing. Preserved for backward compatibility.
860
861 fsanitize=
862 Common Driver Report Joined
863 Select what to sanitize
864
865 fasynchronous-unwind-tables
866 Common Report Var(flag_asynchronous_unwind_tables) Optimization
867 Generate unwind tables that are exact at each instruction boundary
868
869 fauto-inc-dec
870 Common Report Var(flag_auto_inc_dec) Init(1)
871 Generate auto-inc/dec instructions
872
873 ; -fcheck-bounds causes gcc to generate array bounds checks.
874 ; For C, C++ and ObjC: defaults off.
875 ; For Java: defaults to on.
876 ; For Fortran: defaults to off.
877 fbounds-check
878 Common Report Var(flag_bounds_check)
879 Generate code to check bounds before indexing arrays
880
881 fbranch-count-reg
882 Common Report Var(flag_branch_on_count_reg) Optimization
883 Replace add, compare, branch with branch on count register
884
885 fbranch-probabilities
886 Common Report Var(flag_branch_probabilities) Optimization
887 Use profiling information for branch probabilities
888
889 fbranch-target-load-optimize
890 Common Report Var(flag_branch_target_load_optimize) Optimization
891 Perform branch target load optimization before prologue / epilogue threading
892
893 fbranch-target-load-optimize2
894 Common Report Var(flag_branch_target_load_optimize2) Optimization
895 Perform branch target load optimization after prologue / epilogue threading
896
897 fbtr-bb-exclusive
898 Common Report Var(flag_btr_bb_exclusive) Optimization
899 Restrict target load migration not to re-use registers in any basic block
900
901 fcall-saved-
902 Common Joined RejectNegative Var(common_deferred_options) Defer
903 -fcall-saved-<register> Mark <register> as being preserved across functions
904
905 fcall-used-
906 Common Joined RejectNegative Var(common_deferred_options) Defer
907 -fcall-used-<register> Mark <register> as being corrupted by function calls
908
909 ; Nonzero for -fcaller-saves: allocate values in regs that need to
910 ; be saved across function calls, if that produces overall better code.
911 ; Optional now, so people can test it.
912 fcaller-saves
913 Common Report Var(flag_caller_saves) Optimization
914 Save registers around function calls
915
916 fcheck-data-deps
917 Common Report Var(flag_check_data_deps)
918 Compare the results of several data dependence analyzers.
919
920 fcheck-new
921 Common Var(flag_check_new)
922 Check the return value of new in C++
923
924 fcombine-stack-adjustments
925 Common Report Var(flag_combine_stack_adjustments) Optimization
926 Looks for opportunities to reduce stack adjustments and stack references.
927
928 fcommon
929 Common Report Var(flag_no_common,0) Optimization
930 Do not put uninitialized globals in the common section
931
932 fcompare-debug
933 Driver
934 ; Converted by the driver to -fcompare-debug= options.
935
936 fcompare-debug=
937 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
938 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
939
940 fcompare-debug-second
941 Common Driver RejectNegative Var(flag_compare_debug)
942 Run only the second compilation of -fcompare-debug
943
944 fcompare-elim
945 Common Report Var(flag_compare_elim_after_reload) Optimization
946 Perform comparison elimination after register allocation has finished
947
948 fconserve-stack
949 Common Var(flag_conserve_stack) Optimization
950 Do not perform optimizations increasing noticeably stack usage
951
952 fcprop-registers
953 Common Report Var(flag_cprop_registers) Optimization
954 Perform a register copy-propagation optimization pass
955
956 fcrossjumping
957 Common Report Var(flag_crossjumping) Optimization
958 Perform cross-jumping optimization
959
960 fcse-follow-jumps
961 Common Report Var(flag_cse_follow_jumps) Optimization
962 When running CSE, follow jumps to their targets
963
964 fcse-skip-blocks
965 Common Ignore
966 Does nothing. Preserved for backward compatibility.
967
968 fcx-limited-range
969 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
970 Omit range reduction step when performing complex division
971
972 fcx-fortran-rules
973 Common Report Var(flag_cx_fortran_rules) Optimization
974 Complex multiplication and division follow Fortran rules
975
976 fdata-sections
977 Common Report Var(flag_data_sections) Optimization
978 Place data items into their own section
979
980 fdbg-cnt-list
981 Common Report Var(common_deferred_options) Defer
982 List all available debugging counters with their limits and counts.
983
984 fdbg-cnt=
985 Common RejectNegative Joined Var(common_deferred_options) Defer
986 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
987
988 fdebug-prefix-map=
989 Common Joined RejectNegative Var(common_deferred_options) Defer
990 Map one directory name to another in debug information
991
992 fdebug-types-section
993 Common Report Var(flag_debug_types_section) Init(0)
994 Output .debug_types section when using DWARF v4 debuginfo.
995
996 ; Nonzero for -fdefer-pop: don't pop args after each function call
997 ; instead save them up to pop many calls' args with one insns.
998 fdefer-pop
999 Common Report Var(flag_defer_pop) Optimization
1000 Defer popping functions args from stack until later
1001
1002 fdelayed-branch
1003 Common Report Var(flag_delayed_branch) Optimization
1004 Attempt to fill delay slots of branch instructions
1005
1006 fdelete-dead-exceptions
1007 Common Report Var(flag_delete_dead_exceptions) Init(0)
1008 Delete dead instructions that may throw exceptions
1009
1010 fdelete-null-pointer-checks
1011 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
1012 Delete useless null pointer checks
1013
1014 fdevirtualize-speculatively
1015 Common Report Var(flag_devirtualize_speculatively) Optimization
1016 Perform speculative devirtualization
1017
1018 fdevirtualize
1019 Common Report Var(flag_devirtualize) Optimization
1020 Try to convert virtual calls to direct ones.
1021
1022 fdiagnostics-show-location=
1023 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1024 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
1025
1026 ; Required for these enum values.
1027 SourceInclude
1028 pretty-print.h
1029
1030 Enum
1031 Name(diagnostic_prefixing_rule) Type(int)
1032
1033 EnumValue
1034 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1035
1036 EnumValue
1037 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1038
1039 fdiagnostics-show-caret
1040 Common Var(flag_diagnostics_show_caret) Init(1)
1041 Show the source line with a caret indicating the column
1042
1043 fdiagnostics-color
1044 Common Alias(fdiagnostics-color=,always,never)
1045 ;
1046
1047 fdiagnostics-color=
1048 Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1049 -fdiagnostics-color=[never|always|auto] Colorize diagnostics
1050
1051 ; Required for these enum values.
1052 SourceInclude
1053 diagnostic-color.h
1054
1055 Enum
1056 Name(diagnostic_color_rule) Type(int)
1057
1058 EnumValue
1059 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1060
1061 EnumValue
1062 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1063
1064 EnumValue
1065 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1066
1067 fdiagnostics-show-option
1068 Common Var(flag_diagnostics_show_option) Init(1)
1069 Amend appropriate diagnostic messages with the command line option that controls them
1070
1071 fdisable-
1072 Common Joined RejectNegative Var(common_deferred_options) Defer
1073 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1074
1075 fenable-
1076 Common Joined RejectNegative Var(common_deferred_options) Defer
1077 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1078
1079 fdump-
1080 Common Joined RejectNegative Var(common_deferred_options) Defer
1081 -fdump-<type> Dump various compiler internals to a file
1082
1083 fdump-final-insns
1084 Driver RejectNegative
1085
1086 fdump-final-insns=
1087 Common RejectNegative Joined Var(flag_dump_final_insns)
1088 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1089
1090 fdump-go-spec=
1091 Common RejectNegative Joined Var(flag_dump_go_spec)
1092 -fdump-go-spec=filename Write all declarations to file as Go code
1093
1094 fdump-noaddr
1095 Common Report Var(flag_dump_noaddr)
1096 Suppress output of addresses in debugging dumps
1097
1098 fdump-passes
1099 Common Var(flag_dump_passes) Init(0)
1100 Dump optimization passes
1101
1102 fdump-unnumbered
1103 Common Report Var(flag_dump_unnumbered)
1104 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1105
1106 fdump-unnumbered-links
1107 Common Report Var(flag_dump_unnumbered_links)
1108 Suppress output of previous and next insn numbers in debugging dumps
1109
1110 fdwarf2-cfi-asm
1111 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1112 Enable CFI tables via GAS assembler directives.
1113
1114 fearly-inlining
1115 Common Report Var(flag_early_inlining) Init(1) Optimization
1116 Perform early inlining
1117
1118 feliminate-dwarf2-dups
1119 Common Report Var(flag_eliminate_dwarf2_dups)
1120 Perform DWARF2 duplicate elimination
1121
1122 fipa-sra
1123 Common Report Var(flag_ipa_sra) Init(0) Optimization
1124 Perform interprocedural reduction of aggregates
1125
1126 feliminate-unused-debug-symbols
1127 Common Report Var(flag_debug_only_used_symbols)
1128 Perform unused type elimination in debug info
1129
1130 feliminate-unused-debug-types
1131 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1132 Perform unused type elimination in debug info
1133
1134 femit-class-debug-always
1135 Common Report Var(flag_emit_class_debug_always) Init(0)
1136 Do not suppress C++ class debug information.
1137
1138 fexceptions
1139 Common Report Var(flag_exceptions) Optimization
1140 Enable exception handling
1141
1142 fexpensive-optimizations
1143 Common Report Var(flag_expensive_optimizations) Optimization
1144 Perform a number of minor, expensive optimizations
1145
1146 fexcess-precision=
1147 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1148 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1149
1150 Enum
1151 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1152
1153 EnumValue
1154 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1155
1156 EnumValue
1157 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1158
1159 ffast-math
1160 Common
1161
1162 ffat-lto-objects
1163 Common Var(flag_fat_lto_objects)
1164 Output lto objects containing both the intermediate language and binary output.
1165
1166 ffinite-math-only
1167 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1168 Assume no NaNs or infinities are generated
1169
1170 ffixed-
1171 Common Joined RejectNegative Var(common_deferred_options) Defer
1172 -ffixed-<register> Mark <register> as being unavailable to the compiler
1173
1174 ffloat-store
1175 Common Report Var(flag_float_store) Optimization
1176 Don't allocate floats and doubles in extended-precision registers
1177
1178 fforce-addr
1179 Common Ignore
1180 Does nothing. Preserved for backward compatibility.
1181
1182 fforward-propagate
1183 Common Report Var(flag_forward_propagate) Optimization
1184 Perform a forward propagation pass on RTL
1185
1186 ffp-contract=
1187 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1188 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1189
1190 Enum
1191 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1192
1193 EnumValue
1194 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1195
1196 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1197 EnumValue
1198 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1199
1200 EnumValue
1201 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1202
1203 ; Nonzero means don't put addresses of constant functions in registers.
1204 ; Used for compiling the Unix kernel, where strange substitutions are
1205 ; done on the assembly output.
1206 ffunction-cse
1207 Common Report Var(flag_no_function_cse,0)
1208 Allow function addresses to be held in registers
1209
1210 ffunction-sections
1211 Common Report Var(flag_function_sections)
1212 Place each function into its own section
1213
1214 fgcse
1215 Common Report Var(flag_gcse) Optimization
1216 Perform global common subexpression elimination
1217
1218 fgcse-lm
1219 Common Report Var(flag_gcse_lm) Init(1) Optimization
1220 Perform enhanced load motion during global common subexpression elimination
1221
1222 fgcse-sm
1223 Common Report Var(flag_gcse_sm) Init(0) Optimization
1224 Perform store motion after global common subexpression elimination
1225
1226 fgcse-las
1227 Common Report Var(flag_gcse_las) Init(0) Optimization
1228 Perform redundant load after store elimination in global common subexpression
1229 elimination
1230
1231 fgcse-after-reload
1232 Common Report Var(flag_gcse_after_reload) Optimization
1233 Perform global common subexpression elimination after register allocation
1234 has finished
1235
1236 ; This option is not documented yet as its semantics will change.
1237 fgraphite
1238 Common Report Var(flag_graphite)
1239 Enable in and out of Graphite representation
1240
1241 fgraphite-identity
1242 Common Report Var(flag_graphite_identity) Optimization
1243 Enable Graphite Identity transformation
1244
1245 fhoist-adjacent-loads
1246 Common Report Var(flag_hoist_adjacent_loads) Optimization
1247 Enable hoisting adjacent loads to encourage generating conditional move
1248 instructions
1249
1250 floop-parallelize-all
1251 Common Report Var(flag_loop_parallelize_all) Optimization
1252 Mark all loops as parallel
1253
1254 floop-strip-mine
1255 Common Report Var(flag_loop_strip_mine) Optimization
1256 Enable Loop Strip Mining transformation
1257
1258 floop-interchange
1259 Common Report Var(flag_loop_interchange) Optimization
1260 Enable Loop Interchange transformation
1261
1262 floop-block
1263 Common Report Var(flag_loop_block) Optimization
1264 Enable Loop Blocking transformation
1265
1266 fgnu-tm
1267 Common Report Var(flag_tm)
1268 Enable support for GNU transactional memory
1269
1270 floop-flatten
1271 Common Ignore
1272 Does nothing. Preserved for backward compatibility.
1273
1274 floop-nest-optimize
1275 Common Report Var(flag_loop_optimize_isl) Optimization
1276 Enable the ISL based loop nest optimizer
1277
1278 fstrict-volatile-bitfields
1279 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1280 Force bitfield accesses to match their type width
1281
1282 fguess-branch-probability
1283 Common Report Var(flag_guess_branch_prob) Optimization
1284 Enable guessing of branch probabilities
1285
1286 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1287 ; Generate position-independent code for executables if possible
1288 ; On SVR4 targets, it also controls whether or not to emit a
1289 ; string identifying the compiler.
1290 fident
1291 Common Report Var(flag_no_ident,0)
1292 Process #ident directives
1293
1294 fif-conversion
1295 Common Report Var(flag_if_conversion) Optimization
1296 Perform conversion of conditional jumps to branchless equivalents
1297
1298 fif-conversion2
1299 Common Report Var(flag_if_conversion2) Optimization
1300 Perform conversion of conditional jumps to conditional execution
1301
1302 fstack-reuse=
1303 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL)
1304 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1305
1306 Enum
1307 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1308
1309 EnumValue
1310 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1311
1312 EnumValue
1313 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1314
1315 EnumValue
1316 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1317
1318 ftree-loop-if-convert
1319 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1320 Convert conditional jumps in innermost loops to branchless equivalents
1321
1322 ftree-loop-if-convert-stores
1323 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1324 Also if-convert conditional jumps containing memory writes
1325
1326 ; -finhibit-size-directive inhibits output of .size for ELF.
1327 ; This is used only for compiling crtstuff.c,
1328 ; and it may be extended to other effects
1329 ; needed for crtstuff.c on other systems.
1330 finhibit-size-directive
1331 Common Report Var(flag_inhibit_size_directive)
1332 Do not generate .size directives
1333
1334 findirect-inlining
1335 Common Report Var(flag_indirect_inlining)
1336 Perform indirect inlining
1337
1338 ; General flag to enable inlining. Specifying -fno-inline will disable
1339 ; all inlining apart from always-inline functions.
1340 finline
1341 Common Report Var(flag_no_inline,0) Init(0) Optimization
1342 Enable inlining of function declared \"inline\", disabling disables all inlining
1343
1344 finline-small-functions
1345 Common Report Var(flag_inline_small_functions) Optimization
1346 Integrate functions into their callers when code size is known not to grow
1347
1348 finline-functions
1349 Common Report Var(flag_inline_functions) Optimization
1350 Integrate functions not declared \"inline\" into their callers when profitable
1351
1352 finline-functions-called-once
1353 Common Report Var(flag_inline_functions_called_once) Optimization
1354 Integrate functions only required by their single caller
1355
1356 finline-limit-
1357 Common RejectNegative Joined Alias(finline-limit=)
1358
1359 finline-limit=
1360 Common RejectNegative Joined UInteger
1361 -finline-limit=<number> Limit the size of inlined functions to <number>
1362
1363 finline-atomics
1364 Common Report Var(flag_inline_atomics) Init(1) Optimization
1365 Inline __atomic operations when a lock free instruction sequence is available.
1366
1367 finstrument-functions
1368 Common Report Var(flag_instrument_function_entry_exit)
1369 Instrument function entry and exit with profiling calls
1370
1371 finstrument-functions-exclude-function-list=
1372 Common RejectNegative Joined
1373 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1374
1375 finstrument-functions-exclude-file-list=
1376 Common RejectNegative Joined
1377 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1378
1379 fipa-cp
1380 Common Report Var(flag_ipa_cp) Optimization
1381 Perform interprocedural constant propagation
1382
1383 fipa-cp-clone
1384 Common Report Var(flag_ipa_cp_clone) Optimization
1385 Perform cloning to make Interprocedural constant propagation stronger
1386
1387 fipa-profile
1388 Common Report Var(flag_ipa_profile) Init(0) Optimization
1389 Perform interprocedural profile propagation
1390
1391 fipa-pta
1392 Common Report Var(flag_ipa_pta) Init(0) Optimization
1393 Perform interprocedural points-to analysis
1394
1395 fipa-pure-const
1396 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1397 Discover pure and const functions
1398
1399 fipa-reference
1400 Common Report Var(flag_ipa_reference) Init(0) Optimization
1401 Discover readonly and non addressable static variables
1402
1403 fipa-matrix-reorg
1404 Common Ignore
1405 Does nothing. Preserved for backward compatibility.
1406
1407 fipa-struct-reorg
1408 Common Ignore
1409 Does nothing. Preserved for backward compatibility.
1410
1411 fira-algorithm=
1412 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1413 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1414
1415 Enum
1416 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1417
1418 EnumValue
1419 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1420
1421 EnumValue
1422 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1423
1424 fira-region=
1425 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1426 -fira-region=[one|all|mixed] Set regions for IRA
1427
1428 Enum
1429 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1430
1431 EnumValue
1432 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1433
1434 EnumValue
1435 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1436
1437 EnumValue
1438 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1439
1440 fira-hoist-pressure
1441 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1442 Use IRA based register pressure calculation
1443 in RTL hoist optimizations.
1444
1445 fira-loop-pressure
1446 Common Report Var(flag_ira_loop_pressure) Optimization
1447 Use IRA based register pressure calculation
1448 in RTL loop optimizations.
1449
1450 fira-share-save-slots
1451 Common Report Var(flag_ira_share_save_slots) Init(1)
1452 Share slots for saving different hard registers.
1453
1454 fira-share-spill-slots
1455 Common Report Var(flag_ira_share_spill_slots) Init(1)
1456 Share stack slots for spilled pseudo-registers.
1457
1458 fira-verbose=
1459 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1460 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1461
1462 fivopts
1463 Common Report Var(flag_ivopts) Init(1) Optimization
1464 Optimize induction variables on trees
1465
1466 fjump-tables
1467 Common Var(flag_jump_tables) Init(1) Optimization
1468 Use jump tables for sufficiently large switch statements
1469
1470 fkeep-inline-functions
1471 Common Report Var(flag_keep_inline_functions)
1472 Generate code for functions even if they are fully inlined
1473
1474 fkeep-static-consts
1475 Common Report Var(flag_keep_static_consts) Init(1)
1476 Emit static const variables even if they are not used
1477
1478 fleading-underscore
1479 Common Report Var(flag_leading_underscore) Init(-1)
1480 Give external symbols a leading underscore
1481
1482 floop-optimize
1483 Common Ignore
1484 Does nothing. Preserved for backward compatibility.
1485
1486 flto
1487 Common
1488 Enable link-time optimization.
1489
1490 flto=
1491 Common RejectNegative Joined Var(flag_lto)
1492 Link-time optimization with number of parallel jobs or jobserver.
1493
1494 flto-partition=1to1
1495 Common Var(flag_lto_partition_1to1)
1496 Partition symbols and vars at linktime based on object files they originate from
1497
1498 flto-partition=balanced
1499 Common Var(flag_lto_partition_balanced)
1500 Partition functions and vars at linktime into approximately same sized buckets
1501
1502 flto-partition=max
1503 Common Var(flag_lto_partition_max)
1504 Put every symbol into separate partition
1505
1506 flto-partition=none
1507 Common Var(flag_lto_partition_none)
1508 Disable partioning and streaming
1509
1510 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1511 flto-compression-level=
1512 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1513 -flto-compression-level=<number> Use zlib compression level <number> for IL
1514
1515 flto-report
1516 Common Report Var(flag_lto_report) Init(0)
1517 Report various link-time optimization statistics
1518
1519 flto-report-wpa
1520 Common Report Var(flag_lto_report_wpa) Init(0)
1521 Report various link-time optimization statistics for WPA only
1522
1523 fmath-errno
1524 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1525 Set errno after built-in math functions
1526
1527 fmax-errors=
1528 Common Joined RejectNegative UInteger Var(flag_max_errors)
1529 -fmax-errors=<number> Maximum number of errors to report
1530
1531 fmem-report
1532 Common Report Var(mem_report)
1533 Report on permanent memory allocation
1534
1535 fmem-report-wpa
1536 Common Report Var(mem_report_wpa)
1537 Report on permanent memory allocation in WPA only
1538
1539 ; This will attempt to merge constant section constants, if 1 only
1540 ; string constants and constants from constant pool, if 2 also constant
1541 ; variables.
1542 fmerge-all-constants
1543 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1544 Attempt to merge identical constants and constant variables
1545
1546 fmerge-constants
1547 Common Report Var(flag_merge_constants,1) Optimization
1548 Attempt to merge identical constants across compilation units
1549
1550 fmerge-debug-strings
1551 Common Report Var(flag_merge_debug_strings) Init(1)
1552 Attempt to merge identical debug strings across compilation units
1553
1554 fmessage-length=
1555 Common RejectNegative Joined UInteger
1556 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1557
1558 fmodulo-sched
1559 Common Report Var(flag_modulo_sched) Optimization
1560 Perform SMS based modulo scheduling before the first scheduling pass
1561
1562 fmodulo-sched-allow-regmoves
1563 Common Report Var(flag_modulo_sched_allow_regmoves)
1564 Perform SMS based modulo scheduling with register moves allowed
1565
1566 fmove-loop-invariants
1567 Common Report Var(flag_move_loop_invariants) Optimization
1568 Move loop invariant computations out of loops
1569
1570 fdce
1571 Common Var(flag_dce) Init(1) Optimization
1572 Use the RTL dead code elimination pass
1573
1574 fdse
1575 Common Var(flag_dse) Init(1) Optimization
1576 Use the RTL dead store elimination pass
1577
1578 freschedule-modulo-scheduled-loops
1579 Common Report Var(flag_resched_modulo_sched) Optimization
1580 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1581
1582 fnon-call-exceptions
1583 Common Report Var(flag_non_call_exceptions) Optimization
1584 Support synchronous non-call exceptions
1585
1586 fomit-frame-pointer
1587 Common Report Var(flag_omit_frame_pointer) Optimization
1588 When possible do not generate stack frames
1589
1590 fopt-info
1591 Common Report Var(flag_opt_info) Optimization
1592 Enable all optimization info dumps on stderr
1593
1594 fopt-info-
1595 Common Joined RejectNegative Var(common_deferred_options) Defer
1596 -fopt-info[-<type>=filename] Dump compiler optimization details
1597
1598 foptimize-register-move
1599 Common Ignore
1600 Does nothing. Preserved for backward compatibility.
1601
1602 foptimize-sibling-calls
1603 Common Report Var(flag_optimize_sibling_calls) Optimization
1604 Optimize sibling and tail recursive calls
1605
1606 fpartial-inlining
1607 Common Report Var(flag_partial_inlining)
1608 Perform partial inlining
1609
1610 fpre-ipa-mem-report
1611 Common Report Var(pre_ipa_mem_report)
1612 Report on memory allocation before interprocedural optimization
1613
1614 fpost-ipa-mem-report
1615 Common Report Var(post_ipa_mem_report)
1616 Report on memory allocation before interprocedural optimization
1617
1618 fpack-struct
1619 Common Report Var(flag_pack_struct) Optimization
1620 Pack structure members together without holes
1621
1622 fpack-struct=
1623 Common RejectNegative Joined UInteger Optimization
1624 -fpack-struct=<number> Set initial maximum structure member alignment
1625
1626 fpcc-struct-return
1627 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1628 Return small aggregates in memory, not registers
1629
1630 fpeel-loops
1631 Common Report Var(flag_peel_loops) Optimization
1632 Perform loop peeling
1633
1634 fpeephole
1635 Common Report Var(flag_no_peephole,0) Optimization
1636 Enable machine specific peephole optimizations
1637
1638 fpeephole2
1639 Common Report Var(flag_peephole2) Optimization
1640 Enable an RTL peephole pass before sched2
1641
1642 fPIC
1643 Common Report Var(flag_pic,2) Negative(fPIE)
1644 Generate position-independent code if possible (large mode)
1645
1646 fPIE
1647 Common Report Var(flag_pie,2) Negative(fpic)
1648 Generate position-independent code for executables if possible (large mode)
1649
1650 fpic
1651 Common Report Var(flag_pic,1) Negative(fpie)
1652 Generate position-independent code if possible (small mode)
1653
1654 fpie
1655 Common Report Var(flag_pie,1) Negative(fPIC)
1656 Generate position-independent code for executables if possible (small mode)
1657
1658 fplugin=
1659 Common Joined RejectNegative Var(common_deferred_options) Defer
1660 Specify a plugin to load
1661
1662 fplugin-arg-
1663 Common Joined RejectNegative Var(common_deferred_options) Defer
1664 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1665
1666 fpredictive-commoning
1667 Common Report Var(flag_predictive_commoning) Optimization
1668 Run predictive commoning optimization.
1669
1670 fprefetch-loop-arrays
1671 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1672 Generate prefetch instructions, if available, for arrays in loops
1673
1674 fprofile
1675 Common Report Var(profile_flag)
1676 Enable basic program profiling code
1677
1678 fprofile-arcs
1679 Common Report Var(profile_arc_flag)
1680 Insert arc-based program profiling code
1681
1682 fprofile-dir=
1683 Common Joined RejectNegative Var(profile_data_prefix)
1684 Set the top-level directory for storing the profile data.
1685 The default is 'pwd'.
1686
1687 fprofile-correction
1688 Common Report Var(flag_profile_correction)
1689 Enable correction of flow inconsistent profile data input
1690
1691 fprofile-generate
1692 Common
1693 Enable common options for generating profile info for profile feedback directed optimizations
1694
1695 fprofile-generate=
1696 Common Joined RejectNegative
1697 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1698
1699 fprofile-use
1700 Common Var(flag_profile_use)
1701 Enable common options for performing profile feedback directed optimizations
1702
1703 fprofile-use=
1704 Common Joined RejectNegative
1705 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1706
1707 fprofile-values
1708 Common Report Var(flag_profile_values)
1709 Insert code to profile values of expressions
1710
1711 fprofile-report
1712 Common Report Var(profile_report)
1713 Report on consistency of profile
1714
1715 fprofile-reorder-functions
1716 Common Report Var(flag_profile_reorder_functions)
1717 Enable function reordering that improves code placement
1718
1719 frandom-seed
1720 Common Var(common_deferred_options) Defer
1721
1722 frandom-seed=
1723 Common Joined RejectNegative Var(common_deferred_options) Defer
1724 -frandom-seed=<string> Make compile reproducible using <string>
1725
1726 ; This switch causes the command line that was used to create an
1727 ; object file to be recorded into the object file. The exact format
1728 ; of this recording is target and binary file format dependent.
1729 ; It is related to the -fverbose-asm switch, but that switch only
1730 ; records information in the assembler output file as comments, so
1731 ; they never reach the object file.
1732 frecord-gcc-switches
1733 Common Report Var(flag_record_gcc_switches)
1734 Record gcc command line switches in the object file.
1735
1736 freg-struct-return
1737 Common Report Var(flag_pcc_struct_return,0) Optimization
1738 Return small aggregates in registers
1739
1740 fregmove
1741 Common Ignore
1742 Does nothing. Preserved for backward compatibility.
1743
1744 flive-range-shrinkage
1745 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
1746 Relief of register pressure through live range shrinkage
1747
1748 frename-registers
1749 Common Report Var(flag_rename_registers) Init(2) Optimization
1750 Perform a register renaming optimization pass
1751
1752 freorder-blocks
1753 Common Report Var(flag_reorder_blocks) Optimization
1754 Reorder basic blocks to improve code placement
1755
1756 freorder-blocks-and-partition
1757 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1758 Reorder basic blocks and partition into hot and cold sections
1759
1760 freorder-functions
1761 Common Report Var(flag_reorder_functions) Optimization
1762 Reorder functions to improve code placement
1763
1764 frerun-cse-after-loop
1765 Common Report Var(flag_rerun_cse_after_loop) Optimization
1766 Add a common subexpression elimination pass after loop optimizations
1767
1768 frerun-loop-opt
1769 Common Ignore
1770 Does nothing. Preserved for backward compatibility.
1771
1772 frounding-math
1773 Common Report Var(flag_rounding_math) Optimization SetByCombined
1774 Disable optimizations that assume default FP rounding behavior
1775
1776 fsched-interblock
1777 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1778 Enable scheduling across basic blocks
1779
1780 fsched-pressure
1781 Common Report Var(flag_sched_pressure) Init(0) Optimization
1782 Enable register pressure sensitive insn scheduling
1783
1784 fsched-spec
1785 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1786 Allow speculative motion of non-loads
1787
1788 fsched-spec-load
1789 Common Report Var(flag_schedule_speculative_load) Optimization
1790 Allow speculative motion of some loads
1791
1792 fsched-spec-load-dangerous
1793 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1794 Allow speculative motion of more loads
1795
1796 fsched-verbose=
1797 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1798 -fsched-verbose=<number> Set the verbosity level of the scheduler
1799
1800 fsched2-use-superblocks
1801 Common Report Var(flag_sched2_use_superblocks) Optimization
1802 If scheduling post reload, do superblock scheduling
1803
1804 fsched2-use-traces
1805 Common Ignore
1806 Does nothing. Preserved for backward compatibility.
1807
1808 fschedule-insns
1809 Common Report Var(flag_schedule_insns) Optimization
1810 Reschedule instructions before register allocation
1811
1812 fschedule-insns2
1813 Common Report Var(flag_schedule_insns_after_reload) Optimization
1814 Reschedule instructions after register allocation
1815
1816 ; This flag should be on when a target implements non-trivial
1817 ; scheduling hooks, maybe saving some information for its own sake.
1818 ; On IA64, for example, this is used for correct bundling.
1819 fselective-scheduling
1820 Common Report Var(flag_selective_scheduling) Optimization
1821 Schedule instructions using selective scheduling algorithm
1822
1823 fselective-scheduling2
1824 Common Report Var(flag_selective_scheduling2) Optimization
1825 Run selective scheduling after reload
1826
1827 fsel-sched-pipelining
1828 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1829 Perform software pipelining of inner loops during selective scheduling
1830
1831 fsel-sched-pipelining-outer-loops
1832 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1833 Perform software pipelining of outer loops during selective scheduling
1834
1835 fsel-sched-reschedule-pipelined
1836 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1837 Reschedule pipelined regions without pipelining
1838
1839 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1840 ; of stalled insns into the ready list.
1841 fsched-stalled-insns
1842 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1843 Allow premature scheduling of queued insns
1844
1845 fsched-stalled-insns=
1846 Common RejectNegative Joined UInteger
1847 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1848
1849 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1850 ; be examined for a dependency on a stalled insn that is candidate for
1851 ; premature removal from the queue of stalled insns into the ready list (has
1852 ; an effect only if the flag 'sched_stalled_insns' is set).
1853 fsched-stalled-insns-dep
1854 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1855 Set dependence distance checking in premature scheduling of queued insns
1856
1857 fsched-stalled-insns-dep=
1858 Common RejectNegative Joined UInteger
1859 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1860
1861 fsched-group-heuristic
1862 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1863 Enable the group heuristic in the scheduler
1864
1865 fsched-critical-path-heuristic
1866 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1867 Enable the critical path heuristic in the scheduler
1868
1869 fsched-spec-insn-heuristic
1870 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1871 Enable the speculative instruction heuristic in the scheduler
1872
1873 fsched-rank-heuristic
1874 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1875 Enable the rank heuristic in the scheduler
1876
1877 fsched-last-insn-heuristic
1878 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1879 Enable the last instruction heuristic in the scheduler
1880
1881 fsched-dep-count-heuristic
1882 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1883 Enable the dependent count heuristic in the scheduler
1884
1885 fsection-anchors
1886 Common Report Var(flag_section_anchors) Optimization
1887 Access data in the same section from shared anchor points
1888
1889 fsee
1890 Common Ignore
1891 Does nothing. Preserved for backward compatibility.
1892
1893 fzee
1894 Common Ignore
1895 Does nothing. Preserved for backward compatibility.
1896
1897 free
1898 Common Report Var(flag_ree) Init(0)
1899 Turn on Redundant Extensions Elimination pass.
1900
1901 fshow-column
1902 Common Report Var(flag_show_column) Init(1)
1903 Show column numbers in diagnostics, when available. Default on
1904
1905 fshrink-wrap
1906 Common Report Var(flag_shrink_wrap) Optimization
1907 Emit function prologues only before parts of the function that need it,
1908 rather than at the top of the function.
1909
1910 fsignaling-nans
1911 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1912 Disable optimizations observable by IEEE signaling NaNs
1913
1914 fsigned-zeros
1915 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1916 Disable floating point optimizations that ignore the IEEE signedness of zero
1917
1918 fsingle-precision-constant
1919 Common Report Var(flag_single_precision_constant) Optimization
1920 Convert floating point constants to single precision constants
1921
1922 fsplit-ivs-in-unroller
1923 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1924 Split lifetimes of induction variables when loops are unrolled
1925
1926 fsplit-stack
1927 Common Report Var(flag_split_stack) Init(-1)
1928 Generate discontiguous stack frames
1929
1930 fsplit-wide-types
1931 Common Report Var(flag_split_wide_types) Optimization
1932 Split wide types into independent registers
1933
1934 fvariable-expansion-in-unroller
1935 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1936 Apply variable expansion when loops are unrolled
1937
1938 fstack-check=
1939 Common Report RejectNegative Joined
1940 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1941
1942 fstack-check
1943 Common Alias(fstack-check=, specific, no)
1944 Insert stack checking code into the program. Same as -fstack-check=specific
1945
1946 fstack-limit
1947 Common Var(common_deferred_options) Defer
1948
1949 fstack-limit-register=
1950 Common RejectNegative Joined Var(common_deferred_options) Defer
1951 -fstack-limit-register=<register> Trap if the stack goes past <register>
1952
1953 fstack-limit-symbol=
1954 Common RejectNegative Joined Var(common_deferred_options) Defer
1955 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1956
1957 fstack-protector
1958 Common Report Var(flag_stack_protect, 1)
1959 Use propolice as a stack protection method
1960
1961 fstack-protector-all
1962 Common Report RejectNegative Var(flag_stack_protect, 2)
1963 Use a stack protection method for every function
1964
1965 fstack-protector-strong
1966 Common Report RejectNegative Var(flag_stack_protect, 3)
1967 Use a smart stack protection method for certain functions
1968
1969 fstack-usage
1970 Common RejectNegative Var(flag_stack_usage)
1971 Output stack usage information on a per-function basis
1972
1973 fstrength-reduce
1974 Common Ignore
1975 Does nothing. Preserved for backward compatibility.
1976
1977 ; Nonzero if we should do (language-dependent) alias analysis.
1978 ; Typically, this analysis will assume that expressions of certain
1979 ; types do not alias expressions of certain other types. Only used
1980 ; if alias analysis (in general) is enabled.
1981 fstrict-aliasing
1982 Common Report Var(flag_strict_aliasing) Optimization
1983 Assume strict aliasing rules apply
1984
1985 fstrict-overflow
1986 Common Report Var(flag_strict_overflow)
1987 Treat signed overflow as undefined
1988
1989 fsync-libcalls
1990 Common Report Var(flag_sync_libcalls) Init(1)
1991 Implement __atomic operations via libcalls to legacy __sync functions
1992
1993 fsyntax-only
1994 Common Report Var(flag_syntax_only)
1995 Check for syntax errors, then stop
1996
1997 ftest-coverage
1998 Common Report Var(flag_test_coverage)
1999 Create data files needed by \"gcov\"
2000
2001 fthread-jumps
2002 Common Report Var(flag_thread_jumps) Optimization
2003 Perform jump threading optimizations
2004
2005 ftime-report
2006 Common Report Var(time_report)
2007 Report the time taken by each compiler pass
2008
2009 ftls-model=
2010 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2011 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
2012
2013 Enum
2014 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2015
2016 EnumValue
2017 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2018
2019 EnumValue
2020 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2021
2022 EnumValue
2023 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2024
2025 EnumValue
2026 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2027
2028 ftoplevel-reorder
2029 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
2030 Reorder top level functions, variables, and asms
2031
2032 ftracer
2033 Common Report Var(flag_tracer)
2034 Perform superblock formation via tail duplication
2035
2036 ; Zero means that floating-point math operations cannot generate a
2037 ; (user-visible) trap. This is the case, for example, in nonstop
2038 ; IEEE 754 arithmetic.
2039 ftrapping-math
2040 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2041 Assume floating-point operations can trap
2042
2043 ftrapv
2044 Common Report Var(flag_trapv) Optimization
2045 Trap for signed overflow in addition, subtraction and multiplication
2046
2047 ftree-ccp
2048 Common Report Var(flag_tree_ccp) Optimization
2049 Enable SSA-CCP optimization on trees
2050
2051 ftree-bit-ccp
2052 Common Report Var(flag_tree_bit_ccp) Optimization
2053 Enable SSA-BIT-CCP optimization on trees
2054
2055 ftree-store-ccp
2056 Common Ignore
2057 Does nothing. Preserved for backward compatibility.
2058
2059 ftree-ch
2060 Common Report Var(flag_tree_ch) Optimization
2061 Enable loop header copying on trees
2062
2063 ftree-coalesce-inlined-vars
2064 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
2065 Enable coalescing of copy-related user variables that are inlined
2066
2067 ftree-coalesce-vars
2068 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
2069 Enable coalescing of all copy-related user variables
2070
2071 ftree-copyrename
2072 Common Report Var(flag_tree_copyrename) Optimization
2073 Replace SSA temporaries with better names in copies
2074
2075 ftree-copy-prop
2076 Common Report Var(flag_tree_copy_prop) Optimization
2077 Enable copy propagation on trees
2078
2079 ftree-store-copy-prop
2080 Common Ignore
2081 Does nothing. Preserved for backward compatibility.
2082
2083 ftree-cselim
2084 Common Report Var(flag_tree_cselim) Init(2) Optimization
2085 Transform condition stores into unconditional ones
2086
2087 ftree-switch-conversion
2088 Common Report Var(flag_tree_switch_conversion) Optimization
2089 Perform conversions of switch initializations.
2090
2091 ftree-dce
2092 Common Report Var(flag_tree_dce) Optimization
2093 Enable SSA dead code elimination optimization on trees
2094
2095 ftree-dominator-opts
2096 Common Report Var(flag_tree_dom) Optimization
2097 Enable dominator optimizations
2098
2099 ftree-tail-merge
2100 Common Report Var(flag_tree_tail_merge) Optimization
2101 Enable tail merging on trees
2102
2103 ftree-dse
2104 Common Report Var(flag_tree_dse) Optimization
2105 Enable dead store elimination
2106
2107 ftree-forwprop
2108 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2109 Enable forward propagation on trees
2110
2111 ftree-fre
2112 Common Report Var(flag_tree_fre) Optimization
2113 Enable Full Redundancy Elimination (FRE) on trees
2114
2115 foptimize-strlen
2116 Common Report Var(flag_optimize_strlen) Optimization
2117 Enable string length optimizations on trees
2118
2119 fisolate-erroneous-paths-dereference
2120 Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization
2121 Detect paths which trigger erroneous or undefined behaviour due to
2122 dereferencing a NULL pointer. Isolate those paths from the main control
2123 flow and turn the statement with erroneous or undefined behaviour into a trap.
2124
2125 fisolate-erroneous-paths-attribute
2126 Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization
2127 Detect paths which trigger erroneous or undefined behaviour due a NULL value
2128 being used in a way which is forbidden by a returns_nonnull or nonnull
2129 attribute. Isolate those paths from the main control flow and turn the
2130 statement with erroneous or undefined behaviour into a trap.
2131
2132 ftree-loop-distribution
2133 Common Report Var(flag_tree_loop_distribution) Optimization
2134 Enable loop distribution on trees
2135
2136 ftree-loop-distribute-patterns
2137 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2138 Enable loop distribution for patterns transformed into a library call
2139
2140 ftree-loop-im
2141 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2142 Enable loop invariant motion on trees
2143
2144 ftree-loop-linear
2145 Common Alias(floop-interchange)
2146 Enable loop interchange transforms. Same as -floop-interchange
2147
2148 ftree-loop-ivcanon
2149 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2150 Create canonical induction variables in loops
2151
2152 ftree-loop-optimize
2153 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2154 Enable loop optimizations on tree level
2155
2156 ftree-parallelize-loops=
2157 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2158 Enable automatic parallelization of loops
2159
2160 ftree-phiprop
2161 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2162 Enable hoisting loads from conditional pointers.
2163
2164 ftree-pre
2165 Common Report Var(flag_tree_pre) Optimization
2166 Enable SSA-PRE optimization on trees
2167
2168 ftree-partial-pre
2169 Common Report Var(flag_tree_partial_pre) Optimization
2170 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2171
2172 ftree-pta
2173 Common Report Var(flag_tree_pta) Optimization
2174 Perform function-local points-to analysis on trees.
2175
2176 ftree-reassoc
2177 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2178 Enable reassociation on tree level
2179
2180 ftree-salias
2181 Common Ignore
2182 Does nothing. Preserved for backward compatibility.
2183
2184 ftree-sink
2185 Common Report Var(flag_tree_sink) Optimization
2186 Enable SSA code sinking on trees
2187
2188 ftree-slsr
2189 Common Report Var(flag_tree_slsr) Optimization
2190 Perform straight-line strength reduction
2191
2192 ftree-sra
2193 Common Report Var(flag_tree_sra) Optimization
2194 Perform scalar replacement of aggregates
2195
2196 ftree-ter
2197 Common Report Var(flag_tree_ter) Optimization
2198 Replace temporary expressions in the SSA->normal pass
2199
2200 ftree-lrs
2201 Common Report Var(flag_tree_live_range_split) Optimization
2202 Perform live range splitting during the SSA->normal pass
2203
2204 ftree-vrp
2205 Common Report Var(flag_tree_vrp) Init(0) Optimization
2206 Perform Value Range Propagation on trees
2207
2208 funit-at-a-time
2209 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2210 Compile whole compilation unit at a time
2211
2212 funroll-loops
2213 Common Report Var(flag_unroll_loops) Optimization
2214 Perform loop unrolling when iteration count is known
2215
2216 funroll-all-loops
2217 Common Report Var(flag_unroll_all_loops) Optimization
2218 Perform loop unrolling for all loops
2219
2220 ; Nonzero means that loop optimizer may assume that the induction variables
2221 ; that control loops do not overflow and that the loops with nontrivial
2222 ; exit condition are not infinite
2223 funsafe-loop-optimizations
2224 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2225 Allow loop optimizations to assume that the loops behave in normal way
2226
2227 fassociative-math
2228 Common Report Var(flag_associative_math) SetByCombined
2229 Allow optimization for floating-point arithmetic which may change the
2230 result of the operation due to rounding.
2231
2232 freciprocal-math
2233 Common Report Var(flag_reciprocal_math) SetByCombined
2234 Same as -fassociative-math for expressions which include division.
2235
2236 ; Nonzero means that unsafe floating-point math optimizations are allowed
2237 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2238 ; are allowed to assume that their arguments and results are "normal"
2239 ; (e.g., nonnegative for SQRT).
2240 funsafe-math-optimizations
2241 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2242 Allow math optimizations that may violate IEEE or ISO standards
2243
2244 funswitch-loops
2245 Common Report Var(flag_unswitch_loops) Optimization
2246 Perform loop unswitching
2247
2248 funwind-tables
2249 Common Report Var(flag_unwind_tables) Optimization
2250 Just generate unwind tables for exception handling
2251
2252 fuse-ld=bfd
2253 Common Driver Negative(fuse-ld=gold)
2254 Use the bfd linker instead of the default linker
2255
2256 fuse-ld=gold
2257 Common Driver Negative(fuse-ld=bfd)
2258 Use the gold linker instead of the default linker
2259
2260 fuse-linker-plugin
2261 Common Undocumented Var(flag_use_linker_plugin)
2262
2263 ; Positive if we should track variables, negative if we should run
2264 ; the var-tracking pass only to discard debug annotations, zero if
2265 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2266 ; will be set according to optimize, debug_info_level and debug_hooks
2267 ; in process_options ().
2268 fvar-tracking
2269 Common Report Var(flag_var_tracking) Init(2) Optimization
2270 Perform variable tracking
2271
2272 ; Positive if we should track variables at assignments, negative if
2273 ; we should run the var-tracking pass only to discard debug
2274 ; annotations. When flag_var_tracking_assignments ==
2275 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2276 fvar-tracking-assignments
2277 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2278 Perform variable tracking by annotating assignments
2279
2280 ; Nonzero if we should toggle flag_var_tracking_assignments after
2281 ; processing options and computing its default. */
2282 fvar-tracking-assignments-toggle
2283 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2284 Toggle -fvar-tracking-assignments
2285
2286 ; Positive if we should track uninitialized variables, negative if
2287 ; we should run the var-tracking pass only to discard debug
2288 ; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
2289 ; will be set according to flag_var_tracking.
2290 fvar-tracking-uninit
2291 Common Report Var(flag_var_tracking_uninit) Optimization
2292 Perform variable tracking and also tag variables that are uninitialized
2293
2294 ftree-vectorize
2295 Common Report Var(flag_tree_vectorize) Optimization
2296 Enable vectorization on trees
2297
2298 ftree-vectorizer-verbose=
2299 Common Joined RejectNegative Ignore
2300 Does nothing. Preserved for backward compatibility.
2301
2302 ftree-loop-vectorize
2303 Common Report Var(flag_tree_loop_vectorize) Optimization
2304 Enable loop vectorization on trees
2305
2306 ftree-slp-vectorize
2307 Common Report Var(flag_tree_slp_vectorize) Optimization
2308 Enable basic block vectorization (SLP) on trees
2309
2310 fvect-cost-model=
2311 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT)
2312 Specifies the cost model for vectorization
2313
2314 fsimd-cost-model=
2315 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED)
2316 Specifies the vectorization cost model for code marked with a simd directive
2317
2318 Enum
2319 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2320
2321 EnumValue
2322 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2323
2324 EnumValue
2325 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2326
2327 EnumValue
2328 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2329
2330 fvect-cost-model
2331 Common RejectNegative Alias(fvect-cost-model=,dynamic)
2332 Enables the dynamic vectorizer cost model. Preserved for backward compatibility.
2333
2334 fno-vect-cost-model
2335 Common RejectNegative Alias(fvect-cost-model=,unlimited)
2336 Enables the unlimited vectorizer cost model. Preserved for backward compatibility.
2337
2338 ftree-vect-loop-version
2339 Common Ignore
2340 Does nothing. Preserved for backward compatibility.
2341
2342 ftree-scev-cprop
2343 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2344 Enable copy propagation of scalar-evolution information.
2345
2346 ; -fverbose-asm causes extra commentary information to be produced in
2347 ; the generated assembly code (to make it more readable). This option
2348 ; is generally only of use to those who actually need to read the
2349 ; generated assembly code (perhaps while debugging the compiler itself).
2350 ; -fno-verbose-asm, the default, causes the extra information
2351 ; to not be added and is useful when comparing two assembler files.
2352 fverbose-asm
2353 Common Report Var(flag_verbose_asm)
2354 Add extra commentary to assembler output
2355
2356 fvisibility=
2357 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2358 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2359
2360 Enum
2361 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2362
2363 EnumValue
2364 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2365
2366 EnumValue
2367 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2368
2369 EnumValue
2370 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2371
2372 EnumValue
2373 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2374
2375 fvtable-verify=
2376 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2377 Validate vtable pointers before using them.
2378
2379 Enum
2380 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2381
2382 EnumValue
2383 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2384
2385 EnumValue
2386 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2387
2388 EnumValue
2389 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2390
2391 fvtv-counts
2392 Common Var(flag_vtv_counts)
2393 Output vtable verification counters.
2394
2395 fvtv-debug
2396 Common Var(flag_vtv_debug)
2397 Output vtable verification pointer sets information.
2398
2399 fvpt
2400 Common Report Var(flag_value_profile_transformations) Optimization
2401 Use expression value profiles in optimizations
2402
2403 fweb
2404 Common Report Var(flag_web) Init(2) Optimization
2405 Construct webs and split unrelated uses of single variable
2406
2407 ftree-builtin-call-dce
2408 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2409 Enable conditional dead code elimination for builtin calls
2410
2411 fwhole-program
2412 Common Report Var(flag_whole_program) Init(0) Optimization
2413 Perform whole program optimizations
2414
2415 fwrapv
2416 Common Report Var(flag_wrapv) Optimization
2417 Assume signed arithmetic overflow wraps around
2418
2419 fzero-initialized-in-bss
2420 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2421 Put zero initialized data in the bss section
2422
2423 g
2424 Common JoinedOrMissing
2425 Generate debug information in default format
2426
2427 gcoff
2428 Common JoinedOrMissing Negative(gdwarf)
2429 Generate debug information in COFF format
2430
2431 gdwarf
2432 Common JoinedOrMissing Negative(gdwarf-)
2433 Generate debug information in default version of DWARF format
2434
2435 gdwarf-
2436 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2437 Generate debug information in DWARF v2 (or later) format
2438
2439 ggdb
2440 Common JoinedOrMissing
2441 Generate debug information in default extended format
2442
2443 gno-pubnames
2444 Common Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
2445 Don't generate DWARF pubnames and pubtypes sections.
2446
2447 gpubnames
2448 Common Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
2449 Generate DWARF pubnames and pubtypes sections.
2450
2451 ggnu-pubnames
2452 Common Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
2453 Generate DWARF pubnames and pubtypes sections with GNU extensions.
2454
2455 gno-record-gcc-switches
2456 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2457 Don't record gcc command line switches in DWARF DW_AT_producer.
2458
2459 grecord-gcc-switches
2460 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2461 Record gcc command line switches in DWARF DW_AT_producer.
2462
2463 gno-split-dwarf
2464 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2465 Don't generate debug information in separate .dwo files
2466
2467 gsplit-dwarf
2468 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2469 Generate debug information in separate .dwo files
2470
2471 gstabs
2472 Common JoinedOrMissing Negative(gstabs+)
2473 Generate debug information in STABS format
2474
2475 gstabs+
2476 Common JoinedOrMissing Negative(gvms)
2477 Generate debug information in extended STABS format
2478
2479 gno-strict-dwarf
2480 Common RejectNegative Var(dwarf_strict,0) Init(0)
2481 Emit DWARF additions beyond selected version
2482
2483 gstrict-dwarf
2484 Common Report RejectNegative Var(dwarf_strict,1)
2485 Don't emit DWARF additions beyond selected version
2486
2487 gtoggle
2488 Common Report Var(flag_gtoggle)
2489 Toggle debug information generation
2490
2491 gvms
2492 Common JoinedOrMissing Negative(gxcoff)
2493 Generate debug information in VMS format
2494
2495 gxcoff
2496 Common JoinedOrMissing Negative(gxcoff+)
2497 Generate debug information in XCOFF format
2498
2499 gxcoff+
2500 Common JoinedOrMissing Negative(gcoff)
2501 Generate debug information in extended XCOFF format
2502
2503 h
2504 Driver Joined Separate
2505
2506 iplugindir=
2507 Common Joined Var(plugindir_string) Init(0)
2508 -iplugindir=<dir> Set <dir> to be the default plugin directory
2509
2510 imultiarch
2511 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2512 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory
2513
2514 l
2515 Driver Joined Separate
2516
2517 n
2518 Driver
2519
2520 no-canonical-prefixes
2521 Driver
2522
2523 nodefaultlibs
2524 Driver
2525
2526 nostartfiles
2527 Driver
2528
2529 nostdlib
2530 Driver
2531
2532 o
2533 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2534 -o <file> Place output into <file>
2535
2536 p
2537 Common Var(profile_flag)
2538 Enable function profiling
2539
2540 pass-exit-codes
2541 Driver Var(pass_exit_codes)
2542
2543 pedantic
2544 Common Alias(Wpedantic)
2545
2546 pedantic-errors
2547 Common Var(flag_pedantic_errors)
2548 Like -pedantic but issue them as errors
2549
2550 pg
2551 Driver
2552
2553 pipe
2554 Driver Var(use_pipes)
2555
2556 print-file-name=
2557 Driver JoinedOrMissing Var(print_file_name)
2558
2559 print-libgcc-file-name
2560 Driver
2561
2562 print-multi-directory
2563 Driver Var(print_multi_directory)
2564
2565 print-multi-lib
2566 Driver Var(print_multi_lib)
2567
2568 print-multi-os-directory
2569 Driver Var(print_multi_os_directory)
2570
2571 print-multiarch
2572 Driver Var(print_multiarch)
2573
2574 print-prog-name=
2575 Driver JoinedOrMissing Var(print_prog_name)
2576
2577 print-search-dirs
2578 Driver Var(print_search_dirs)
2579
2580 print-sysroot
2581 Driver Var(print_sysroot)
2582
2583 print-sysroot-headers-suffix
2584 Driver Var(print_sysroot_headers_suffix)
2585
2586 quiet
2587 Common Var(quiet_flag) RejectDriver
2588 Do not display functions compiled or elapsed time
2589
2590 r
2591 Driver
2592
2593 s
2594 Driver
2595
2596 save-temps
2597 Driver
2598
2599 save-temps=
2600 Driver Joined
2601
2602 t
2603 Driver
2604
2605 time
2606 Driver Var(report_times)
2607
2608 time=
2609 Driver JoinedOrMissing
2610
2611 u
2612 Driver Joined Separate
2613
2614 undef
2615 Driver
2616 ; C option, but driver must not handle as "-u ndef".
2617
2618 v
2619 Common Driver Var(verbose_flag)
2620 Enable verbose output
2621
2622 version
2623 Common Var(version_flag) RejectDriver
2624 Display the compiler's version
2625
2626 w
2627 Common Var(inhibit_warnings)
2628 Suppress warnings
2629
2630 wrapper
2631 Driver Separate Var(wrapper_string)
2632
2633 x
2634 Driver Joined Separate
2635
2636 shared
2637 Driver RejectNegative Negative(pie)
2638 Create a shared library
2639
2640 shared-libgcc
2641 Driver
2642
2643 specs
2644 Driver Separate Alias(specs=)
2645
2646 specs=
2647 Driver Joined
2648
2649 static
2650 Driver
2651
2652 static-libgcc
2653 Driver
2654
2655 static-libgfortran
2656 Driver
2657 ; Documented for Fortran, but always accepted by driver.
2658
2659 static-libstdc++
2660 Driver
2661
2662 static-libgo
2663 Driver
2664 ; Documented for Go, but always accepted by driver.
2665
2666 static-libasan
2667 Driver
2668
2669 static-libtsan
2670 Driver
2671
2672 static-liblsan
2673 Driver
2674
2675 static-libubsan
2676 Driver
2677
2678 symbolic
2679 Driver
2680
2681 pie
2682 Driver RejectNegative Negative(shared)
2683 Create a position independent executable
2684
2685 z
2686 Driver Joined Separate
2687
2688 ; This comment is to ensure we retain the blank line above.