1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003-2023 Free Software Foundation, Inc.
5 ; This file is part of GCC.
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
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
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/>.
21 ; See the GCC internals manual (options.texi) for a description of this file's format.
23 ; Please try to keep this file in ASCII collating order.
37 ; Not used directly to control optimizations, only to save -Ofast
38 ; setting for "optimize" attributes.
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.
49 ; This variable is set to non-0 only by LTO front-end. 1 indicates that
50 ; the output produced will be used for incremental linking (thus weak symbols
51 ; can still be bound) and 2 indicates that the IL is going to be linked and
52 ; and output to LTO object file.
54 enum incremental_link flag_incremental_link = INCREMENTAL_LINK_NONE
56 ; 0 means straightforward implementation of complex divide acceptable.
57 ; 1 means wide ranges of inputs must work for complex divide.
58 ; 2 means C99-like requirements for complex multiply and divide.
60 int flag_complex_method = 1
63 int flag_default_complex_method = 1
65 ; Language specific warning pass for unused results.
67 bool flag_warn_unused_result = false
69 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
73 ; Nonzero if we should write GIMPLE bytecode for offload compilation.
75 int flag_generate_offload = 0
77 ; Nonzero means we should be saving declaration info into a .X file.
79 int flag_gen_aux_info = 0
81 ; Nonzero if we are compiling code for a shared library, zero for
86 ; These three are really VEC(char_p,heap) *.
89 void *flag_instrument_functions_exclude_functions
92 void *flag_instrument_functions_exclude_files
95 void *flag_ignored_attributes
97 ; Generic structs (e.g. templates not explicitly specialized)
98 ; may not have a compilation unit associated with them, and so
99 ; may need to be treated differently from ordinary structs.
101 ; Structs only handled by reference (indirectly), will also usually
102 ; not need as much debugging information.
105 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
108 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
110 ; True if we should exit after parsing options.
112 bool exit_after_options
114 ; Type(s) of debugging information we are producing (if any). See
115 ; flag-types.h for the definitions of the different possible types of
116 ; debugging information.
118 uint32_t write_symbols = NO_DEBUG
120 ; Level of debugging information we are producing. See flag-types.h
121 ; for the definitions of the different possible levels.
123 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
125 ; Level of CTF debugging information we are producing. See flag-types.h
126 ; for the definitions of the different possible levels.
128 enum ctf_debug_info_levels ctf_debug_info_level = CTFINFO_LEVEL_NONE
130 ; Original value of maximum field alignment in bytes, specified via
131 ; -fpack-struct=<value>.
133 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
135 ; Type of stack check.
137 enum stack_check_type flag_stack_check = NO_STACK_CHECK
139 ; True if stack usage information needs to be computed.
141 bool flag_stack_usage_info = false
143 ; -dA causes debug commentary information to be produced in
144 ; the generated assembly code (to make it more readable). This option
145 ; is generally only of use to those who actually need to read the
146 ; generated assembly code (perhaps while debugging the compiler itself).
147 ; Currently, this switch is only used by dwarf2out.cc; however, it is intended
148 ; to be a catchall for printing debug information in the assembler file.
152 ; Balance between GNAT encodings and standard DWARF to emit.
154 enum dwarf_gnat_encodings gnat_encodings = DWARF_GNAT_ENCODINGS_DEFAULT
156 ; -dP causes the rtl to be emitted as a comment in assembly.
158 int flag_dump_rtl_in_asm
160 ; Whether -da was passed (used only in handle_common_deferred_options).
162 bool flag_dump_all_passed
164 ; Other flags saying which kinds of debugging dump have been requested.
167 int rtl_dump_and_exit
170 int flag_print_asm_name
172 ; Name of top-level original source file (what was input to cpp).
173 ; This comes from the #-command at the beginning of the actual input.
174 ; If there isn't any there, then this is the cc1 input file name.
176 const char *main_input_filename
178 ; Pointer to base name in main_input_filename, with directories and a
179 ; single final extension removed, and the length of this base
183 const char *main_input_basename
186 int main_input_baselength
188 ; The base name used for auxiliary output files.
189 ; dump_base_name minus dump_base_ext.
192 const char *aux_base_name
194 ; Which options have been printed by --help.
198 ; Which enums have been printed by --help. 0 = not printed, no
199 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
202 char *help_enum_printed
204 ; The number of columns for --help output.
206 unsigned int help_columns
208 ; Whether this options structure has been through finish_options
210 bool flag_opts_finished
212 ; What the sanitizer should instrument
214 unsigned int flag_sanitize
216 ; What sanitizers should recover from errors
218 unsigned int flag_sanitize_recover = (SANITIZE_UNDEFINED | SANITIZE_UNDEFINED_NONDEFAULT | SANITIZE_KERNEL_ADDRESS | SANITIZE_KERNEL_HWADDRESS) & ~(SANITIZE_UNREACHABLE | SANITIZE_RETURN)
220 ; What sanitizers should use __builtin_trap () instead of runtime diagnostics
222 unsigned int flag_sanitize_trap
224 ; Flag whether a prefix has been added to dump_base_name
226 bool dump_base_name_prefixed = false
228 ; What subset of registers should be zeroed on function return
230 unsigned int flag_zero_call_used_regs
242 Common Driver Joined Undocumented
243 Provide bash completion for options starting with provided string.
246 Driver Alias(coverage)
252 Common Separate Alias(d)
255 Common Joined Alias(d)
258 Driver Common Separate Alias(dumpbase)
261 Driver Common Separate Alias(dumpbase-ext)
264 Driver Common Separate Alias(dumpdir)
267 Driver Separate Alias(e)
270 Driver Joined Alias(e)
273 Common Warning Alias(Wextra)
276 Driver Separate Alias(Xassembler)
279 Driver JoinedOrMissing Alias(Xassembler)
282 Driver Separate Alias(Xlinker)
285 Driver JoinedOrMissing Alias(Xlinker)
288 Driver Separate Alias(u)
291 Driver Joined Alias(u)
294 Common Driver Var(help_flag)
295 Display this information.
299 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params.
302 Driver Separate Alias(x)
305 Driver Joined Alias(x)
308 Driver Separate Alias(L)
311 Driver Joined Alias(L)
313 -no-canonical-prefixes
314 Driver Alias(no-canonical-prefixes)
316 -no-standard-libraries
317 Driver Alias(nostdlib)
320 Driver Var(no_sysroot_suffix)
329 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
332 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
335 Driver Alias(pass-exit-codes)
338 Common Alias(Wpedantic)
341 Common Alias(pedantic-errors)
347 Driver Alias(static-pie)
353 Driver Separate Alias(B)
356 Driver JoinedOrMissing Alias(B)
362 Driver Separate Alias(print-file-name=)
365 Driver JoinedOrMissing Alias(print-file-name=)
367 -print-libgcc-file-name
368 Driver Alias(print-libgcc-file-name)
370 -print-multi-directory
371 Driver Alias(print-multi-directory)
374 Driver Alias(print-multi-lib)
376 -print-multi-os-directory
377 Driver Alias(print-multi-os-directory)
380 Driver Alias(print-multiarch)
383 Driver Separate Alias(print-prog-name=)
386 Driver JoinedOrMissing Alias(print-prog-name=)
389 Driver Alias(print-search-dirs)
392 Driver Alias(print-sysroot)
394 -print-sysroot-headers-suffix
395 Driver Alias(print-sysroot-headers-suffix)
401 Driver Alias(save-temps)
407 Driver Separate Alias(specs=)
410 Driver Joined Alias(specs=)
416 Driver Alias(symbolic)
420 Display target specific command line options (including assembler and linker options).
428 ;; The driver used to convert options such as --help into forms such
429 ;; as -fhelp; the following four entries are for compatibility with
430 ;; any direct uses of those (undocumented) -f forms
432 Common Driver Alias(-help)
435 Common Driver Joined Alias(-help=)
438 Common Driver Alias(-target-help)
441 Common Driver Alias(-version)
444 Driver Separate Alias(-sysroot=)
447 Driver JoinedOrMissing
453 Driver Joined Separate
459 Driver Joined Separate
465 Common JoinedOrMissing Optimization
466 -O<number> Set optimization level to <number>.
470 Optimize for space rather than speed.
474 Optimize for speed disregarding exact standards compliance.
478 Optimize for debugging experience rather than speed or size.
482 Optimize for space aggressively rather than speed.
494 Driver Joined Separate
500 Driver Joined Separate
521 Common RejectNegative Warning Alias(Wextra)
522 This switch is deprecated; use -Wextra instead.
525 Driver JoinedOrMissing RejectNegative
528 Driver JoinedOrMissing RejectNegative
531 Driver JoinedOrMissing RejectNegative
534 Common Var(warn_aggregate_return) Warning
535 Warn about returning structures, unions or arrays.
537 Waggressive-loop-optimizations
538 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
539 Warn if a loop with constant number of iterations triggers undefined behavior.
542 Common Alias(Warray-bounds=, 1, 0) Warning
545 Common Joined RejectNegative UInteger Var(warn_array_bounds) Warning IntegerRange(0, 2)
546 Warn if an array is accessed out of bounds.
549 Common Var(warn_use_after_free) Warning
550 Warn for uses of pointers to deallocated storage.
553 Common Joined RejectNegative UInteger Var(warn_use_after_free) Warning IntegerRange(0, 3)
554 Warn for uses of pointers to deallocated storage.
557 Common Var(warn_attributes) Init(1) Warning
558 Warn about inappropriate attribute usage.
562 Do not warn about specified attributes.
565 Common Alias(Wattribute_alias=, 1, 0) Warning
566 Warn about type safety and similar errors and mismatches in declarations with alias attributes.
569 Common Joined RejectNegative UInteger Var(warn_attribute_alias) Init(1) Warning IntegerRange(0, 2)
570 Warn about type safety and similar errors and mismatches in declarations with alias attributes.
573 Common Var(warn_cannot_profile) Init(1) Warning
574 Warn when profiling instrumentation was requested, but could not be applied to
578 Common Var(warn_cast_align) Warning
579 Warn about pointer casts which increase alignment.
582 Common Var(warn_cast_align,2) Warning
583 Warn about pointer casts which increase alignment.
586 Common Var(warn_complain_wrong_lang) Init(1) Warning
587 Complain when a command-line option is valid, but not applicable to the current front end.
590 Common Var(warn_cpp) Init(1) Warning
591 Warn when a #warning directive is encountered.
594 Common Var(warn_attribute_warning) Init(1) Warning
595 Warn about uses of __attribute__((warning)) declarations.
598 Common Var(warn_deprecated) Init(1) Warning
599 Warn if a deprecated compiler feature, class, method, or field is used.
601 Wdeprecated-declarations
602 Common Var(warn_deprecated_decl) Init(1) Warning
603 Warn about uses of __attribute__((deprecated)) declarations.
605 Wdisabled-optimization
606 Common Var(warn_disabled_optimization) Warning
607 Warn when an optimization pass is disabled.
610 Common Var(warnings_are_errors)
611 Treat all warnings as errors.
615 Treat specified warning as error.
618 Common Var(extra_warnings) Warning
619 Print extra (possibly unwanted) warnings.
622 Common Var(flag_fatal_errors)
623 Exit on the first error occurred.
626 Common RejectNegative Joined Host_Wide_Int ByteSize Warning Var(warn_frame_larger_than_size) Init(HOST_WIDE_INT_MAX)
627 -Wframe-larger-than=<byte-size> Warn if a function's stack frame requires in excess of <byte-size>.
629 Wno-frame-larger-than
630 Common Alias(Wframe-larger-than=,18446744073709551615EiB,none) Warning
631 Disable -Wframe-larger-than= warning. Equivalent to -Wframe-larger-than=<SIZE_MAX> or larger.
634 Common Var(warn_free_nonheap_object) Init(1) Warning
635 Warn when attempting to free a non-heap object.
638 Common Ignore Warning
639 Does nothing. Preserved for backward compatibility.
641 Wimplicit-fallthrough
642 Common Alias(Wimplicit-fallthrough=,3,0) Warning
644 Wimplicit-fallthrough=
645 Common Var(warn_implicit_fallthrough) RejectNegative Joined UInteger Warning IntegerRange(0, 5)
646 Warn when a switch case falls through.
649 Var(warn_infinite_recursion) Warning
650 Warn for infinitely recursive calls.
653 Common Var(warn_inline) Warning Optimization
654 Warn when an inlined function cannot be inlined.
656 Winvalid-memory-model
657 Common Var(warn_invalid_memory_model) Init(1) Warning
658 Warn when an atomic memory model parameter is known to be outside the valid range.
661 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
664 Common RejectNegative Joined Host_Wide_Int ByteSize Warning Var(warn_larger_than_size) Init(HOST_WIDE_INT_MAX)
665 -Wlarger-than=<byte-size> Warn if an object's size exceeds <byte-size>.
668 Common Alias(Wlarger-than=,18446744073709551615EiB,none) Warning
669 Disable -Wlarger-than= warning. Equivalent to -Wlarger-than=<SIZE_MAX> or larger.
672 Var(warn_nonnull_compare) Warning
673 Warn if comparing pointer parameter with nonnull attribute with NULL.
676 Common Var(warn_null_dereference) Warning
677 Warn if dereferencing a NULL pointer may lead to erroneous or undefined behavior.
679 Wunsafe-loop-optimizations
680 Common Ignore Warning
681 Does nothing. Preserved for backward compatibility.
684 Common Warning Alias(Wsuggest-attribute=noreturn)
687 Common Var(warn_odr_violations) Init(1) Warning
688 Warn about some C++ One Definition Rule violations during link time optimization.
691 Common Var(warn_overflow) Init(1) Warning
692 Warn about overflow in arithmetic expressions.
695 Common Var(warn_lto_type_mismatch) Init(1) Warning
696 During link time optimization warn about mismatched types of global declarations.
699 Common Var(warn_packed) Warning
700 Warn when the packed attribute has no effect on struct layout.
703 Common Var(warn_padded) Warning
704 Warn when padding is required to align structure members.
707 Common Var(pedantic) Init(0) Warning
708 Issue warnings needed for strict compliance to the standard.
711 Common Var(warn_return_local_addr) Init(1) Warning
712 Warn about returning a pointer/reference to a local or temporary variable.
715 Common Var(warn_shadow) Warning
716 Warn when one variable shadows another. Same as -Wshadow=global.
719 Common Warning Alias(Wshadow)
720 Warn when one variable shadows another (globally).
723 Common Var(warn_shadow_local) Warning EnabledBy(Wshadow)
724 Warn when one local variable shadows another local variable or parameter.
727 Common Warning Undocumented Alias(Wshadow=local)
729 Wshadow=compatible-local
730 Common Var(warn_shadow_compatible_local) Warning EnabledBy(Wshadow=local)
731 Warn when one local variable shadows another local variable or parameter of compatible type.
733 Wshadow-compatible-local
734 Common Warning Undocumented Alias(Wshadow=compatible-local)
737 Common Var(warn_stack_protect) Warning
738 Warn when not issuing stack smashing protection for some reason.
741 Common Joined RejectNegative Host_Wide_Int ByteSize Var(warn_stack_usage) Warning Init(HOST_WIDE_INT_MAX)
742 -Wstack-usage=<byte-size> Warn if stack usage might exceed <byte-size>.
745 Common Alias(Wstack-usage=,18446744073709551615EiB,none) Warning
746 Disable Wstack-usage= warning. Equivalent to Wstack-usage=<SIZE_MAX> or larger.
750 Warn about code which might break strict aliasing rules.
753 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
754 Warn about code which might break strict aliasing rules.
758 Warn about optimizations that assume that signed overflow is undefined.
761 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
762 Warn about optimizations that assume that signed overflow is undefined.
764 Wsuggest-attribute=cold
765 Common Var(warn_suggest_attribute_cold) Warning
766 Warn about functions which might be candidates for __attribute__((cold)).
768 Wsuggest-attribute=const
769 Common Var(warn_suggest_attribute_const) Warning
770 Warn about functions which might be candidates for __attribute__((const)).
772 Wsuggest-attribute=pure
773 Common Var(warn_suggest_attribute_pure) Warning
774 Warn about functions which might be candidates for __attribute__((pure)).
776 Wsuggest-attribute=noreturn
777 Common Var(warn_suggest_attribute_noreturn) Warning
778 Warn about functions which might be candidates for __attribute__((noreturn)).
780 Wsuggest-attribute=malloc
781 Common Var(warn_suggest_attribute_malloc) Warning
782 Warn about functions which might be candidates for __attribute__((malloc)).
785 Common Var(warn_suggest_final_types) Warning
786 Warn about C++ polymorphic types where adding final keyword would improve code quality.
788 Wsuggest-final-methods
789 Common Var(warn_suggest_final_methods) Warning
790 Warn about C++ virtual methods where adding final keyword would improve code quality.
793 Common Var(warn_switch_unreachable) Warning Init(1)
794 Warn about statements between switch's controlling expression and the first
798 Common Var(warn_system_headers) Warning
799 Do not suppress warnings from system headers.
802 Common Var(warn_trampolines) Warning
803 Warn whenever a trampoline is generated.
805 Wtrivial-auto-var-init
806 Common Var(warn_trivial_auto_var_init) Warning Init(0)
807 Warn about cases where -ftrivial-auto-var-init cannot initialize an auto variable.
810 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
811 Warn if a comparison is always true or always false due to the limited range of the data type.
814 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
815 Warn about uninitialized automatic variables.
818 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
819 Warn about maybe uninitialized automatic variables.
822 Common Ignore Warning
823 Does nothing. Preserved for backward compatibility.
826 Common Var(warn_unused) Init(0) Warning
827 Enable all -Wunused- warnings.
829 Wunused-but-set-parameter
830 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
831 Warn when a function parameter is only set, otherwise unused.
833 Wunused-but-set-variable
834 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
835 Warn when a variable is only set, otherwise unused.
838 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
839 Warn when a function is unused.
842 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
843 Warn when a label is unused.
846 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
847 Warn when a function parameter is unused.
850 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
851 Warn when an expression value is unused.
854 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
855 Warn when a variable is unused.
858 Common Var(warn_coverage_mismatch) Init(1) Warning
859 Warn in case profiles in -fprofile-use do not match.
861 Wcoverage-invalid-line-number
862 Common Var(warn_coverage_invalid_linenum) Init(1) Warning
863 Warn in case a function ends earlier than it begins due to an invalid linenum macros.
866 Common Var(warn_missing_profile) Init(1) Warning
867 Warn in case profiles in -fprofile-use do not exist.
869 Wvector-operation-performance
870 Common Var(warn_vector_operation_performance) Warning
871 Warn when a vector operation is compiled outside the SIMD.
874 Common Var(warn_tsan) Init(1) Warning
875 Warn about unsupported features in ThreadSanitizer.
890 Common Separate Var(aux_info_file_name)
891 -aux-info <file> Emit declaration information into <file>.
894 Common Joined Alias(aux-info)
904 -d<letters> Enable dumps from specific passes of the compiler.
907 Driver Common Separate Var(dump_base_name)
908 -dumpbase <file> Set the file basename to be used for dumps.
911 Driver Common Separate Var(dump_base_ext)
912 -dumpbase-ext .<ext> Drop a trailing .<ext> from the dump basename to name auxiliary output files.
915 Driver Common Separate Var(dump_dir_name)
916 -dumpdir <dir> Set the directory name to be used for dumps.
931 Driver Joined Separate
933 ; This option has historically been passed down to the linker by an
934 ; accident of a %{e*} spec, so ensure it continues to be passed down
935 ; as a single option. The supported option for this purpose is
936 ; -rdynamic. See PR 47390.
940 ; The version of the C++ ABI in use. The following values are allowed:
942 ; 0: The version of the ABI believed most conformant with the C++ ABI
943 ; specification. This ABI may change as bugs are discovered and fixed.
944 ; Therefore, 0 will not necessarily indicate the same ABI in different
947 ; 1: The version of the ABI first used in G++ 3.2. No longer selectable.
949 ; 2: The version of the ABI first used in G++ 3.4, and the default
952 ; 3: The version of the ABI that fixes the missing underscore
953 ; in template non-type arguments of pointer type.
955 ; 4: The version of the ABI that introduces unambiguous mangling of
956 ; vector types. First selectable in G++ 4.5.
958 ; 5: The version of the ABI that ignores attribute const/noreturn
959 ; in function pointer mangling, and corrects mangling of decltype and
960 ; function parameters used in other parameters and the return type.
961 ; First selectable in G++ 4.6.
963 ; 6: The version of the ABI that doesn't promote scoped enums to int and
964 ; changes the mangling of template argument packs, const/static_cast,
965 ; prefix ++ and --, and a class scope function used as a template
967 ; First selectable in G++ 4.7.
969 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
970 ; corrects the mangling of lambdas in default argument scope.
971 ; First selectable in G++ 4.8.
973 ; 8: The version of the ABI that corrects the substitution behavior of
974 ; function types with function-cv-qualifiers.
975 ; First selectable in G++ 4.9 and default in G++ 5.
977 ; 9: The version of the ABI that corrects the alignment of nullptr_t.
978 ; First selectable and default in G++ 5.2.
980 ; 10: The version of the ABI that mangles attributes that affect type
981 ; identity, such as ia32 calling convention attributes (stdcall, etc.)
982 ; Default in G++ 6 (set in c_common_post_options).
984 ; 11: The version of the ABI that corrects mangling of sizeof... expressions
985 ; and introduces new inheriting constructor handling.
988 ; 12: Corrects the calling convention for classes with only deleted copy/move
989 ; constructors and changes passing/returning of empty records.
990 ; Default in G++ 8.1.
992 ; 13: Fixes the accidental change in 12 to the calling convention for classes
993 ; with deleted copy constructor and trivial move constructor.
994 ; Default in G++ 8.2.
996 ; 14: Corrects the mangling of nullptr expression.
999 ; 15: Corrects G++ 10 ABI tag regression [PR98481].
1000 ; Available, but not default, in G++ 10.3.
1002 ; 16: Changes the mangling of __alignof__ to be distinct from that of alignof.
1003 ; Adds missing 'on' in mangling of operator names in some cases.
1004 ; Default in G++ 11.
1006 ; 17: Fixes layout of classes that inherit from aggregate classes with default
1007 ; member initializers in C++14 and up.
1008 ; Default in G++ 12.
1010 ; 18: Corrects errors in mangling of lambdas with additional context.
1011 ; Default in G++ 13.
1013 ; 19: Emits ABI tags if needed in structured binding mangled names.
1014 ; Ignores cv-quals on [[no_unique_object]] members.
1015 ; Default in G++ 14.
1017 ; Additional positive integers will be assigned as new versions of
1018 ; the ABI become the default version of the ABI.
1020 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0)
1021 The version of the C++ ABI in use.
1023 faggressive-loop-optimizations
1024 Common Var(flag_aggressive_loop_optimizations) Optimization Init(1)
1025 Aggressively optimize loops using language constraints.
1028 Common Var(flag_align_functions) Optimization
1029 Align the start of functions.
1032 Common RejectNegative Joined Var(str_align_functions) Optimization
1034 flimit-function-alignment
1035 Common Var(flag_limit_function_alignment) Optimization Init(0)
1038 Common Var(flag_align_jumps) Optimization
1039 Align labels which are only reached by jumping.
1042 Common RejectNegative Joined Var(str_align_jumps) Optimization
1045 Common Var(flag_align_labels) Optimization
1049 Common RejectNegative Joined Var(str_align_labels) Optimization
1052 Common Var(flag_align_loops) Optimization
1053 Align the start of loops.
1056 Common RejectNegative Joined Var(str_align_loops) Optimization
1058 fallow-store-data-races
1059 Common Var(flag_store_data_races) Optimization
1060 Allow the compiler to introduce new data races on stores.
1063 Common Var(flag_analyzer)
1064 Enable static analysis pass.
1068 Does nothing. Preserved for backward compatibility.
1072 Does nothing. Preserved for backward compatibility.
1074 fargument-noalias-global
1076 Does nothing. Preserved for backward compatibility.
1078 fargument-noalias-anything
1080 Does nothing. Preserved for backward compatibility.
1083 Common Driver Joined
1084 Select what to sanitize.
1087 Common Joined Enum(sanitize_coverage) Var(flag_sanitize_coverage) EnumBitSet
1088 Select type of coverage sanitization.
1091 Name(sanitize_coverage) Type(int)
1094 Enum(sanitize_coverage) String(trace-pc) Value(SANITIZE_COV_TRACE_PC)
1097 Enum(sanitize_coverage) String(trace-cmp) Value(SANITIZE_COV_TRACE_CMP)
1099 fasan-shadow-offset=
1100 Common Joined RejectNegative Var(common_deferred_options) Defer
1101 -fasan-shadow-offset=<number> Use custom shadow memory offset.
1104 Common Joined RejectNegative Var(common_deferred_options) Defer
1105 -fsanitize-sections=<sec1,sec2,...> Sanitize global variables
1106 in user-defined sections.
1110 After diagnosing undefined behavior attempt to continue execution.
1114 This switch is deprecated; use -fsanitize-recover= instead.
1117 Common Driver Joined
1118 Use traps instead of diagnostics of undefined behavior sanitizers.
1123 fsanitize-address-use-after-scope
1124 Common Driver Var(flag_sanitize_address_use_after_scope) Init(0)
1126 fsanitize-undefined-trap-on-error
1127 Common Driver Alias(fsanitize-trap)
1128 This switch is deprecated; use -fsanitize-trap= instead.
1130 fasynchronous-unwind-tables
1131 Common Var(flag_asynchronous_unwind_tables) Optimization
1132 Generate unwind tables that are exact at each instruction boundary.
1135 Common Var(flag_auto_inc_dec) Init(1) Optimization
1136 Generate auto-inc/dec instructions.
1139 Common Var(flag_auto_profile)
1140 Use sample profile information for call graph node weights. The default
1141 profile file is fbdata.afdo in 'pwd'.
1144 Common Joined RejectNegative Var(auto_profile_file)
1145 Use sample profile information for call graph node weights. The profile
1146 file is specified in the argument.
1148 ; -fcheck-bounds causes gcc to generate array bounds checks.
1149 ; For C, C++ and ObjC: defaults off.
1150 ; For Java: defaults to on.
1151 ; For Fortran: defaults to off.
1153 Common Var(flag_bounds_check)
1154 Generate code to check bounds before indexing arrays.
1157 Common Var(flag_branch_on_count_reg) Optimization
1158 Replace add, compare, branch with branch on count register.
1160 fbranch-probabilities
1161 Common Var(flag_branch_probabilities) Optimization
1162 Use profiling information for branch probabilities.
1164 fbranch-target-load-optimize
1166 Does nothing. Preserved for backward compatibility.
1168 fbranch-target-load-optimize2
1170 Does nothing. Preserved for backward compatibility.
1174 Does nothing. Preserved for backward compatibility.
1177 Common RejectNegative Var(flag_callgraph_info) Init(NO_CALLGRAPH_INFO);
1178 Output callgraph information on a per-file basis.
1181 Common RejectNegative Joined
1182 Output callgraph information on a per-file basis with decorations.
1185 Common Joined RejectNegative Var(common_deferred_options) Defer
1186 -fcall-saved-<register> Mark <register> as being preserved across functions.
1189 Common Joined RejectNegative Var(common_deferred_options) Defer
1190 -fcall-used-<register> Mark <register> as being corrupted by function calls.
1192 ; Nonzero for -fcaller-saves: allocate values in regs that need to
1193 ; be saved across function calls, if that produces overall better code.
1194 ; Optional now, so people can test it.
1196 Common Var(flag_caller_saves) Optimization
1197 Save registers around function calls.
1201 This switch is deprecated; do not use.
1204 Common Var(flag_check_new)
1205 Check the return value of new in C++.
1208 Common Var(flag_checking) Init(CHECKING_P ? ENABLE_EXTRA_CHECKING ? 2 : 1 : 0)
1209 Perform internal consistency checkings.
1212 Common Joined RejectNegative UInteger Var(flag_checking)
1213 Perform internal consistency checkings.
1216 Common Var(common_deferred_options) Defer
1217 For -f*-prefix-map= options compare canonicalized pathnames rather than just strings.
1220 Common Var(flag_code_hoisting) Optimization
1221 Enable code hoisting.
1223 fcombine-stack-adjustments
1224 Common Var(flag_combine_stack_adjustments) Optimization
1225 Looks for opportunities to reduce stack adjustments and stack references.
1228 Common Var(flag_no_common,0) Init(1)
1229 Put uninitialized globals in the common section.
1233 ; Converted by the driver to -fcompare-debug= options.
1236 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
1237 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump.
1239 fcompare-debug-second
1240 Common Driver RejectNegative Var(flag_compare_debug)
1241 Run only the second compilation of -fcompare-debug.
1244 Common Var(flag_compare_elim_after_reload) Optimization
1245 Perform comparison elimination after register allocation has finished.
1248 Common Var(flag_conserve_stack) Optimization
1249 Do not perform optimizations increasing noticeably stack usage.
1252 Common Var(flag_cprop_registers) Optimization
1253 Perform a register copy-propagation optimization pass.
1256 Common Var(flag_crossjumping) Optimization
1257 Perform cross-jumping optimization.
1260 Common Var(flag_cse_follow_jumps) Optimization
1261 When running CSE, follow jumps to their targets.
1265 Does nothing. Preserved for backward compatibility.
1268 Common Var(flag_cx_limited_range) Optimization SetByCombined
1269 Omit range reduction step when performing complex division.
1272 Common Var(flag_cx_fortran_rules) Optimization
1273 Complex multiplication and division follow Fortran rules.
1276 Common Var(flag_data_sections)
1277 Place data items into their own section.
1280 Common Var(flag_dbg_cnt_list)
1281 List all available debugging counters with their limits and counts.
1284 Common RejectNegative Joined Var(common_deferred_options) Defer
1285 -fdbg-cnt=<counter>[:<lower_limit1>-]<upper_limit1>[:<lower_limit2>-<upper_limit2>:...][,<counter>:...] Set the debug counter limit.
1288 Common Joined RejectNegative Var(common_deferred_options) Defer
1289 -fdebug-prefix-map=<old>=<new> Map one directory name to another in debug information.
1292 Common Joined RejectNegative Var(common_deferred_options) Defer
1293 -ffile-prefix-map=<old>=<new> Map one directory name to another in compilation result.
1295 fdebug-types-section
1296 Common Var(flag_debug_types_section) Init(0)
1297 Output .debug_types section when using DWARF v4 debuginfo.
1299 ; Nonzero for -fdefer-pop: don't pop args after each function call
1300 ; instead save them up to pop many calls' args with one insns.
1302 Common Var(flag_defer_pop) Optimization
1303 Defer popping functions args from stack until later.
1306 Common Var(flag_delayed_branch) Optimization
1307 Attempt to fill delay slots of branch instructions.
1309 fdelete-dead-exceptions
1310 Common Var(flag_delete_dead_exceptions) Init(0) Optimization
1311 Delete dead instructions that may throw exceptions.
1313 fdelete-null-pointer-checks
1314 Common Var(flag_delete_null_pointer_checks) Init(-1) Optimization
1315 Delete useless null pointer checks.
1317 fdevirtualize-at-ltrans
1318 Common Var(flag_ltrans_devirtualize)
1319 Stream extra data to support more aggressive devirtualization in LTO local transformation mode.
1321 fdevirtualize-speculatively
1322 Common Var(flag_devirtualize_speculatively) Optimization
1323 Perform speculative devirtualization.
1326 Common Var(flag_devirtualize) Optimization
1327 Try to convert virtual calls to direct ones.
1329 fdiagnostics-show-location=
1330 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1331 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics.
1333 ; Required for these enum values.
1338 Name(diagnostic_prefixing_rule) Type(int)
1341 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1344 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1346 fdiagnostics-show-caret
1347 Common Var(flag_diagnostics_show_caret) Init(1)
1348 Show the source line with a caret indicating the column.
1350 fdiagnostics-show-labels
1351 Common Var(flag_diagnostics_show_labels) Init(1)
1352 Show labels annotating ranges of source code when showing source.
1354 fdiagnostics-show-line-numbers
1355 Common Var(flag_diagnostics_show_line_numbers) Init(1)
1356 Show line numbers in the left margin when showing source.
1359 Common Alias(fdiagnostics-color=,always,never)
1363 Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1364 -fdiagnostics-color=[never|always|auto] Colorize diagnostics.
1366 ; Required for these enum values.
1371 Name(diagnostic_color_rule) Type(int)
1374 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1377 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1380 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1383 Driver Common Joined RejectNegative Var(flag_diagnostics_show_urls) Enum(diagnostic_url_rule) Init(DIAGNOSTICS_URL_AUTO)
1384 -fdiagnostics-urls=[never|always|auto] Embed URLs in diagnostics.
1386 ; Required for these enum values.
1391 Name(diagnostic_url_rule) Type(int)
1394 Enum(diagnostic_url_rule) String(never) Value(DIAGNOSTICS_URL_NO)
1397 Enum(diagnostic_url_rule) String(always) Value(DIAGNOSTICS_URL_YES)
1400 Enum(diagnostic_url_rule) String(auto) Value(DIAGNOSTICS_URL_AUTO)
1402 fdiagnostics-column-unit=
1403 Common Joined RejectNegative Enum(diagnostics_column_unit)
1404 -fdiagnostics-column-unit=[display|byte] Select whether column numbers are output as display columns (default) or raw bytes.
1406 fdiagnostics-column-origin=
1407 Common Joined RejectNegative UInteger
1408 -fdiagnostics-column-origin=<number> Set the number of the first column. The default is 1-based as per GNU style, but some utilities may expect 0-based, for example.
1410 fdiagnostics-format=
1411 Common Joined RejectNegative Enum(diagnostics_output_format)
1412 -fdiagnostics-format=[text|sarif-stderr|sarif-file|json|json-stderr|json-file] Select output format.
1414 fdiagnostics-escape-format=
1415 Common Joined RejectNegative Enum(diagnostics_escape_format)
1416 -fdiagnostics-escape-format=[unicode|bytes] Select how to escape non-printable-ASCII bytes in the source for diagnostics that suggest it.
1418 ; Required for these enum values.
1423 Name(diagnostics_column_unit) Type(int)
1426 Enum(diagnostics_column_unit) String(display) Value(DIAGNOSTICS_COLUMN_UNIT_DISPLAY)
1429 Enum(diagnostics_column_unit) String(byte) Value(DIAGNOSTICS_COLUMN_UNIT_BYTE)
1432 Name(diagnostics_escape_format) Type(int)
1435 Enum(diagnostics_escape_format) String(unicode) Value(DIAGNOSTICS_ESCAPE_FORMAT_UNICODE)
1438 Enum(diagnostics_escape_format) String(bytes) Value(DIAGNOSTICS_ESCAPE_FORMAT_BYTES)
1441 Name(diagnostics_output_format) Type(int)
1444 Enum(diagnostics_output_format) String(text) Value(DIAGNOSTICS_OUTPUT_FORMAT_TEXT)
1447 Enum(diagnostics_output_format) String(json) Value(DIAGNOSTICS_OUTPUT_FORMAT_JSON_STDERR)
1450 Enum(diagnostics_output_format) String(json-stderr) Value(DIAGNOSTICS_OUTPUT_FORMAT_JSON_STDERR)
1453 Enum(diagnostics_output_format) String(json-file) Value(DIAGNOSTICS_OUTPUT_FORMAT_JSON_FILE)
1456 Enum(diagnostics_output_format) String(sarif-stderr) Value(DIAGNOSTICS_OUTPUT_FORMAT_SARIF_STDERR)
1459 Enum(diagnostics_output_format) String(sarif-file) Value(DIAGNOSTICS_OUTPUT_FORMAT_SARIF_FILE)
1461 fdiagnostics-parseable-fixits
1462 Common Var(flag_diagnostics_parseable_fixits)
1463 Print fix-it hints in machine-readable form.
1465 fdiagnostics-generate-patch
1466 Common Var(flag_diagnostics_generate_patch)
1467 Print fix-it hints to stderr in unified diff format.
1469 fdiagnostics-show-option
1470 Common Var(flag_diagnostics_show_option) Init(1)
1471 Amend appropriate diagnostic messages with the command line option that controls them.
1473 fdiagnostics-show-cwe
1474 Common Var(flag_diagnostics_show_cwe) Init(1)
1475 Print CWE identifiers for diagnostic messages, where available.
1477 fdiagnostics-show-rules
1478 Common Var(flag_diagnostics_show_rules) Init(1)
1479 Print any rules associated with diagnostic messages.
1481 fdiagnostics-path-format=
1482 Common Joined RejectNegative Var(flag_diagnostics_path_format) Enum(diagnostic_path_format) Init(DPF_INLINE_EVENTS)
1483 Specify how to print any control-flow path associated with a diagnostic.
1485 fdiagnostics-plain-output
1486 Driver Common RejectNegative
1487 Turn off any diagnostics features that complicate the output, such as line numbers, color, and warning URLs.
1490 Common Joined RejectNegative UInteger
1491 -ftabstop=<number> Distance between tab stops for column reporting.
1494 Name(diagnostic_path_format) Type(int)
1497 Enum(diagnostic_path_format) String(none) Value(DPF_NONE)
1500 Enum(diagnostic_path_format) String(separate-events) Value(DPF_SEPARATE_EVENTS)
1503 Enum(diagnostic_path_format) String(inline-events) Value(DPF_INLINE_EVENTS)
1505 fdiagnostics-show-path-depths
1506 Common Var(flag_diagnostics_show_path_depths) Init(0)
1507 Show stack depths of events in paths.
1509 fdiagnostics-text-art-charset=
1510 Driver Common Joined RejectNegative Var(flag_diagnostics_text_art_charset) Enum(diagnostic_text_art_charset) Init(DIAGNOSTICS_TEXT_ART_CHARSET_EMOJI)
1511 -fdiagnostics-text-art-charset=[none|ascii|unicode|emoji] Determine which characters to use in text arg diagrams.
1513 ; Required for these enum values.
1515 diagnostic-text-art.h
1518 Name(diagnostic_text_art_charset) Type(int)
1521 Enum(diagnostic_text_art_charset) String(none) Value(DIAGNOSTICS_TEXT_ART_CHARSET_NONE)
1524 Enum(diagnostic_text_art_charset) String(ascii) Value(DIAGNOSTICS_TEXT_ART_CHARSET_ASCII)
1527 Enum(diagnostic_text_art_charset) String(unicode) Value(DIAGNOSTICS_TEXT_ART_CHARSET_UNICODE)
1530 Enum(diagnostic_text_art_charset) String(emoji) Value(DIAGNOSTICS_TEXT_ART_CHARSET_EMOJI)
1532 fdiagnostics-minimum-margin-width=
1533 Common Joined UInteger Var(diagnostics_minimum_margin_width) Init(6)
1534 Set minimum width of left margin of source code when showing source.
1537 Common Joined RejectNegative Var(common_deferred_options) Defer
1538 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 Disable an optimization pass.
1541 Common Joined RejectNegative Var(common_deferred_options) Defer
1542 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 Enable an optimization pass.
1545 Common Joined RejectNegative Var(common_deferred_options) Defer
1546 -fdump-<type> Dump various compiler internals to a file.
1549 Driver RejectNegative
1552 Common RejectNegative Joined Var(flag_dump_final_insns)
1553 -fdump-final-insns=filename Dump to filename the insns at the end of translation.
1556 Common RejectNegative Joined Var(flag_dump_go_spec)
1557 -fdump-go-spec=filename Write all declarations to file as Go code.
1560 Common Var(flag_dump_noaddr)
1561 Suppress output of addresses in debugging dumps.
1564 Common Driver Var(flag_report_bug)
1565 Collect and dump debug information into temporary file if ICE in C/C++
1568 fdump-internal-locations
1569 Common Var(flag_dump_locations) Init(0)
1570 Dump detailed information on GCC's internal representation of source code locations.
1573 Common Var(flag_dump_passes) Init(0)
1574 Dump optimization passes.
1577 Common Var(flag_dump_unnumbered)
1578 Suppress output of instruction numbers, line number notes and addresses in debugging dumps.
1580 fdump-unnumbered-links
1581 Common Var(flag_dump_unnumbered_links)
1582 Suppress output of previous and next insn numbers in debugging dumps.
1585 Common Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1586 Enable CFI tables via GAS assembler directives.
1589 Common Var(flag_early_inlining) Init(1) Optimization
1590 Perform early inlining.
1592 feliminate-dwarf2-dups
1594 Does nothing. Preserved for backward compatibility.
1597 Common Var(flag_ipa_sra) Init(0) Optimization
1598 Perform interprocedural reduction of aggregates.
1600 feliminate-unused-debug-symbols
1601 Common Var(flag_debug_only_used_symbols) Init(1)
1602 Perform unused symbol elimination in debug info.
1604 feliminate-unused-debug-types
1605 Common Var(flag_eliminate_unused_debug_types) Init(1)
1606 Perform unused type elimination in debug info.
1608 femit-class-debug-always
1609 Common Var(flag_emit_class_debug_always) Init(0)
1610 Do not suppress C++ class debug information.
1613 Common Var(flag_exceptions) Optimization EnabledBy(fnon-call-exceptions)
1614 Enable exception handling.
1616 fexpensive-optimizations
1617 Common Var(flag_expensive_optimizations) Optimization
1618 Perform a number of minor, expensive optimizations.
1621 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision) Init(EXCESS_PRECISION_DEFAULT) Optimization SetByCombined
1622 -fexcess-precision=[fast|standard|16] Specify handling of excess floating-point precision.
1625 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1628 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1631 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1634 Enum(excess_precision) String(16) Value(EXCESS_PRECISION_FLOAT16)
1636 ; Whether we permit the extended set of values for FLT_EVAL_METHOD
1637 ; introduced in ISO/IEC TS 18661-3, or limit ourselves to those in C99/C11.
1638 fpermitted-flt-eval-methods=
1639 Common Joined RejectNegative Enum(permitted_flt_eval_methods) Var(flag_permitted_flt_eval_methods) Init(PERMITTED_FLT_EVAL_METHODS_DEFAULT)
1640 -fpermitted-flt-eval-methods=[c11|ts-18661] Specify which values of FLT_EVAL_METHOD are permitted.
1643 Name(permitted_flt_eval_methods) Type(enum permitted_flt_eval_methods) UnknownError(unknown specification for the set of FLT_EVAL_METHOD values to permit %qs)
1646 Enum(permitted_flt_eval_methods) String(c11) Value(PERMITTED_FLT_EVAL_METHODS_C11)
1649 Enum(permitted_flt_eval_methods) String(ts-18661-3) Value(PERMITTED_FLT_EVAL_METHODS_TS_18661)
1655 Common Var(flag_fat_lto_objects)
1656 Output lto objects containing both the intermediate language and binary output.
1659 Common Var(flag_finite_math_only) Optimization SetByCombined
1660 Assume no NaNs or infinities are generated.
1663 Common Var(flag_finite_loops) Optimization Init(0)
1664 Assume that loops with an exit will terminate and not loop indefinitely.
1667 Common Joined RejectNegative Var(common_deferred_options) Defer
1668 -ffixed-<register> Mark <register> as being unavailable to the compiler.
1671 Common Var(flag_float_store) Optimization
1672 Don't allocate floats and doubles in extended-precision registers.
1676 Does nothing. Preserved for backward compatibility.
1679 Common Var(flag_forward_propagate) Optimization
1680 Perform a forward propagation pass on RTL.
1683 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization
1684 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1687 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1690 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1693 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_ON)
1696 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1698 ffp-int-builtin-inexact
1699 Common Var(flag_fp_int_builtin_inexact) Init(1) Optimization
1700 Allow built-in functions ceil, floor, round, trunc to raise \"inexact\" exceptions.
1702 ; Nonzero means don't put addresses of constant functions in registers.
1703 ; Used for compiling the Unix kernel, where strange substitutions are
1704 ; done on the assembly output.
1706 Common Var(flag_no_function_cse,0) Optimization
1707 Allow function addresses to be held in registers.
1710 Common Var(flag_function_sections)
1711 Place each function into its own section.
1714 Common Var(flag_gcse) Optimization
1715 Perform global common subexpression elimination.
1718 Common Var(flag_gcse_lm) Init(1) Optimization
1719 Perform enhanced load motion during global common subexpression elimination.
1722 Common Var(flag_gcse_sm) Init(0) Optimization
1723 Perform store motion after global common subexpression elimination.
1726 Common Var(flag_gcse_las) Init(0) Optimization
1727 Perform redundant load after store elimination in global common subexpression
1731 Common Var(flag_gcse_after_reload) Optimization
1732 Perform global common subexpression elimination after register allocation has
1736 Name(dwarf_gnat_encodings) Type(int)
1739 Enum(dwarf_gnat_encodings) String(all) Value(DWARF_GNAT_ENCODINGS_ALL)
1742 Enum(dwarf_gnat_encodings) String(gdb) Value(DWARF_GNAT_ENCODINGS_GDB)
1745 Enum(dwarf_gnat_encodings) String(minimal) Value(DWARF_GNAT_ENCODINGS_MINIMAL)
1748 Common Enum(dwarf_gnat_encodings) Joined RejectNegative Undocumented Var(gnat_encodings)
1749 -fgnat-encodings=[all|gdb|minimal] Select the balance between GNAT encodings and standard DWARF emitted in the debug information.
1751 ; This option is not documented yet as its semantics will change.
1753 Common Var(flag_graphite) Optimization
1754 Enable in and out of Graphite representation.
1757 Common Var(flag_graphite_identity) Optimization
1758 Enable Graphite Identity transformation.
1760 fhoist-adjacent-loads
1761 Common Var(flag_hoist_adjacent_loads) Optimization
1762 Enable hoisting adjacent loads to encourage generating conditional move
1766 Common Undocumented Var(flag_keep_gc_roots_live) Optimization
1767 ; Always keep a pointer to a live memory block
1770 Common Var(flag_large_source_files) Init(0)
1771 Improve GCC's ability to track column numbers in large source files,
1772 at the expense of slower compilation.
1774 floop-parallelize-all
1775 Common Var(flag_loop_parallelize_all) Optimization
1776 Mark all loops as parallel.
1779 Common Alias(floop-nest-optimize)
1780 Enable loop nest transforms. Same as -floop-nest-optimize.
1783 Common Var(flag_loop_interchange) Optimization
1784 Enable loop interchange on trees.
1787 Common Alias(floop-nest-optimize)
1788 Enable loop nest transforms. Same as -floop-nest-optimize.
1790 floop-unroll-and-jam
1791 Common Var(flag_unroll_jam) Optimization
1792 Perform unroll-and-jam on loops.
1796 Enable support for GNU transactional memory.
1799 Common Var(flag_gnu_unique) Init(1)
1800 Use STB_GNU_UNIQUE if supported by the assembler.
1804 Does nothing. Preserved for backward compatibility.
1807 Common Var(flag_loop_nest_optimize) Optimization
1808 Enable the loop nest optimizer.
1810 fstrict-volatile-bitfields
1811 Common Var(flag_strict_volatile_bitfields) Init(-1) Optimization
1812 Force bitfield accesses to match their type width.
1815 Common Var(flag_store_merging) Optimization
1816 Merge adjacent stores.
1818 fguess-branch-probability
1819 Common Var(flag_guess_branch_prob) Optimization
1820 Enable guessing of branch probabilities.
1823 Common Var(flag_harden_compares) Optimization
1824 Harden conditionals not used in branches, checking reversed conditions.
1826 fharden-conditional-branches
1827 Common Var(flag_harden_conditional_branches) Optimization
1828 Harden conditional branches by checking reversed conditions.
1830 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1831 ; Generate position-independent code for executables if possible
1832 ; On SVR4 targets, it also controls whether or not to emit a
1833 ; string identifying the compiler.
1835 Common Var(flag_no_ident,0)
1836 Process #ident directives.
1839 Common Var(flag_if_conversion) Optimization
1840 Perform conversion of conditional jumps to branchless equivalents.
1843 Common Var(flag_if_conversion2) Optimization
1844 Perform conversion of conditional jumps to conditional execution.
1847 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization
1848 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1851 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1854 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1857 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1860 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1862 ftree-loop-if-convert
1863 Common Var(flag_tree_loop_if_convert) Init(-1) Optimization
1864 Convert conditional jumps in innermost loops to branchless equivalents.
1866 ftree-loop-if-convert-stores
1868 Does nothing. Preserved for backward compatibility.
1870 ; -finhibit-size-directive inhibits output of .size for ELF.
1871 ; This is used only for compiling crtstuff.c,
1872 ; and it may be extended to other effects
1873 ; needed for crtstuff.c on other systems.
1874 finhibit-size-directive
1875 Common Var(flag_inhibit_size_directive)
1876 Do not generate .size directives.
1879 Common Var(flag_indirect_inlining) Optimization
1880 Perform indirect inlining.
1882 ; General flag to enable inlining. Specifying -fno-inline will disable
1883 ; all inlining apart from always-inline functions.
1885 Common Var(flag_no_inline,0) Init(0) Optimization
1886 Enable inlining of function declared \"inline\", disabling disables all inlining.
1888 finline-small-functions
1889 Common Var(flag_inline_small_functions) Optimization
1890 Integrate functions into their callers when code size is known not to grow.
1893 Common Var(flag_inline_functions) Optimization
1894 Integrate functions not declared \"inline\" into their callers when profitable.
1896 finline-functions-called-once
1897 Common Var(flag_inline_functions_called_once) Optimization
1898 Integrate functions only required by their single caller.
1901 Common RejectNegative Joined Alias(finline-limit=)
1904 Common RejectNegative Joined UInteger
1905 -finline-limit=<number> Limit the size of inlined functions to <number>.
1908 Common Var(flag_inline_atomics) Init(1) Optimization
1909 Inline __atomic operations when a lock free instruction sequence is available.
1912 Common RejectNegative Alias(fcf-protection=,full)
1915 Common Joined RejectNegative Enum(cf_protection_level) EnumSet Var(flag_cf_protection) Init(CF_NONE)
1916 -fcf-protection=[full|branch|return|none|check] Instrument functions with checks to verify jump/call/return control-flow transfer
1917 instructions have valid targets.
1920 Name(cf_protection_level) Type(enum cf_protection_level) UnknownError(unknown Control-Flow Protection Level %qs)
1923 Enum(cf_protection_level) String(full) Value(CF_FULL) Set(1)
1926 Enum(cf_protection_level) String(branch) Value(CF_BRANCH) Set(2)
1929 Enum(cf_protection_level) String(return) Value(CF_RETURN) Set(3)
1932 Enum(cf_protection_level) String(check) Value(CF_CHECK) Set(4)
1935 Enum(cf_protection_level) String(none) Value(CF_NONE) Set(1)
1937 finstrument-functions
1938 Common Var(flag_instrument_function_entry_exit,1)
1939 Instrument function entry and exit with profiling calls.
1941 finstrument-functions-once
1942 Common Var(flag_instrument_function_entry_exit,2)
1943 Instrument function entry and exit with profiling calls invoked once.
1945 finstrument-functions-exclude-function-list=
1946 Common RejectNegative Joined
1947 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions.
1949 finstrument-functions-exclude-file-list=
1950 Common RejectNegative Joined
1951 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files.
1954 Common Var(flag_ipa_cp) Optimization
1955 Perform interprocedural constant propagation.
1958 Common Var(flag_ipa_cp_clone) Optimization
1959 Perform cloning to make Interprocedural constant propagation stronger.
1963 Does nothing. Preserved for backward compatibility.
1966 Common Var(flag_ipa_bit_cp) Optimization
1967 Perform interprocedural bitwise constant propagation.
1970 Common Var(flag_ipa_modref) Optimization
1971 Perform interprocedural modref analysis.
1974 Common Var(flag_ipa_profile) Init(0) Optimization
1975 Perform interprocedural profile propagation.
1978 Common Var(flag_ipa_pta) Init(0) Optimization
1979 Perform interprocedural points-to analysis.
1982 Common Var(flag_ipa_pure_const) Init(0) Optimization
1983 Discover pure and const functions.
1986 Common Var(flag_ipa_icf) Optimization
1987 Perform Identical Code Folding for functions and read-only variables.
1990 Common Var(flag_ipa_icf_functions) Optimization
1991 Perform Identical Code Folding for functions.
1994 Common Var(flag_ipa_icf_variables) Optimization
1995 Perform Identical Code Folding for variables.
1998 Common Var(flag_ipa_reference) Init(0) Optimization
1999 Discover read-only and non addressable static variables.
2001 fipa-reference-addressable
2002 Common Var(flag_ipa_reference_addressable) Init(0) Optimization
2003 Discover read-only, write-only and non-addressable static variables.
2005 fipa-stack-alignment
2006 Common Var(flag_ipa_stack_alignment) Init(1) Optimization
2007 Reduce stack alignment on call sites if possible.
2011 Does nothing. Preserved for backward compatibility.
2015 Does nothing. Preserved for backward compatibility.
2018 Common Var(flag_ipa_vrp) Optimization
2019 Perform IPA Value Range Propagation.
2022 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization
2023 -fira-algorithm=[CB|priority] Set the used IRA algorithm.
2025 fipa-strict-aliasing
2026 Common Var(flag_ipa_strict_aliasing) Init(1) Optimization
2027 Assume strict aliasing rules apply across (uninlined) function boundaries.
2030 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
2033 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
2036 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
2039 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_ONE) Optimization
2040 -fira-region=[one|all|mixed] Set regions for IRA.
2043 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
2046 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
2049 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
2052 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
2055 Common Var(flag_ira_hoist_pressure) Init(1) Optimization
2056 Use IRA based register pressure calculation
2057 in RTL hoist optimizations.
2060 Common Var(flag_ira_loop_pressure) Optimization
2061 Use IRA based register pressure calculation
2062 in RTL loop optimizations.
2064 fira-share-save-slots
2065 Common Var(flag_ira_share_save_slots) Init(1) Optimization
2066 Share slots for saving different hard registers.
2068 fira-share-spill-slots
2069 Common Var(flag_ira_share_spill_slots) Init(1) Optimization
2070 Share stack slots for spilled pseudo-registers.
2073 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
2074 -fira-verbose=<number> Control IRA's level of diagnostic messages.
2077 Common Var(flag_ivopts) Init(1) Optimization
2078 Optimize induction variables on trees.
2081 Common Var(flag_jump_tables) Init(1) Optimization
2082 Use jump tables for sufficiently large switch statements.
2085 Common Var(flag_bit_tests) Init(1) Optimization
2086 Use bit tests for sufficiently large switch statements.
2088 fkeep-inline-functions
2089 Common Var(flag_keep_inline_functions)
2090 Generate code for functions even if they are fully inlined.
2092 fkeep-static-functions
2093 Common Var(flag_keep_static_functions)
2094 Generate code for static functions even if they are never called.
2097 Common Var(flag_keep_static_consts) Init(1)
2098 Emit static const variables even if they are not used.
2101 Common Var(flag_leading_underscore) Init(-1)
2102 Give external symbols a leading underscore.
2106 Does nothing. Preserved for backward compatibility.
2109 Common Var(flag_lra_remat) Optimization
2110 Do CFG-sensitive rematerialization in LRA.
2114 Enable link-time optimization.
2117 Common RejectNegative Joined Var(flag_lto)
2118 Link-time optimization with number of parallel jobs or jobserver.
2121 Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
2124 Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
2127 Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
2130 Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
2133 Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
2136 Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
2139 Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)
2140 Specify the algorithm to partition symbols and vars at linktime.
2142 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
2143 flto-compression-level=
2144 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1) IntegerRange(0, 19)
2145 Use zlib/zstd compression level <number> for IL.
2147 flto-odr-type-merging
2149 Does nothing. Preserved for backward compatibility.
2152 Common Var(flag_lto_report) Init(0)
2153 Report various link-time optimization statistics.
2156 Common Var(flag_lto_report_wpa) Init(0)
2157 Report various link-time optimization statistics for WPA only.
2160 Common Var(flag_errno_math) Init(1) Optimization SetByCombined
2161 Set errno after built-in math functions.
2164 Common Joined RejectNegative UInteger Var(flag_max_errors)
2165 -fmax-errors=<number> Maximum number of errors to report.
2168 Common Var(mem_report)
2169 Report on permanent memory allocation.
2172 Common Var(mem_report_wpa)
2173 Report on permanent memory allocation in WPA only.
2175 ; This will attempt to merge constant section constants, if 1 only
2176 ; string constants and constants from constant pool, if 2 also constant
2178 fmerge-all-constants
2179 Common Var(flag_merge_constants,2) Init(1)
2180 Attempt to merge identical constants and constant variables.
2183 Common Var(flag_merge_constants,1)
2184 Attempt to merge identical constants across compilation units.
2186 fmerge-debug-strings
2187 Common Var(flag_merge_debug_strings) Init(1)
2188 Attempt to merge identical debug strings across compilation units.
2191 Common RejectNegative Joined UInteger
2192 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping.
2195 Common Var(flag_modulo_sched) Optimization
2196 Perform SMS based modulo scheduling before the first scheduling pass.
2198 fmodulo-sched-allow-regmoves
2199 Common Var(flag_modulo_sched_allow_regmoves) Optimization
2200 Perform SMS based modulo scheduling with register moves allowed.
2202 fmove-loop-invariants
2203 Common Var(flag_move_loop_invariants) Optimization
2204 Move loop invariant computations out of loops.
2207 Common Var(flag_move_loop_stores) Optimization
2208 Move stores out of loops.
2212 Building block for specs-based multilib-aware TFLAGS.
2215 Common Var(flag_dce) Init(1) Optimization
2216 Use the RTL dead code elimination pass.
2219 Common Var(flag_dse) Init(0) Optimization
2220 Use the RTL dead store elimination pass.
2222 freschedule-modulo-scheduled-loops
2223 Common Var(flag_resched_modulo_sched) Optimization
2224 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling.
2226 fnon-call-exceptions
2227 Common Var(flag_non_call_exceptions) Optimization
2228 Support synchronous non-call exceptions.
2231 Driver Joined MissingArgError(targets missing after %qs)
2234 Common Driver Joined MissingArgError(options or targets=options missing after %qs)
2235 -foffload-options=<targets>=<options> Specify options for the offloading targets.
2238 Common Joined RejectNegative Enum(offload_abi)
2239 -foffload-abi=[lp64|ilp32] Set the ABI to use in an offload compiler.
2242 Name(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs)
2245 Enum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32)
2248 Enum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64)
2251 Common Var(flag_omit_frame_pointer) Optimization
2252 When possible do not generate stack frames.
2254 fopenmp-target-simd-clone
2255 Common Alias(fopenmp-target-simd-clone=,any,none)
2257 fopenmp-target-simd-clone=
2258 Common Joined RejectNegative Enum(target_simd_clone_device) Var(flag_openmp_target_simd_clone) Init(OMP_TARGET_SIMD_CLONE_NONE) Optimization
2259 Generate SIMD clones for functions with the OpenMP declare target directive.
2262 Name(target_simd_clone_device) Type(int)
2265 Enum(target_simd_clone_device) String(none) Value(OMP_TARGET_SIMD_CLONE_NONE)
2268 Enum(target_simd_clone_device) String(host) Value(OMP_TARGET_SIMD_CLONE_HOST)
2271 Enum(target_simd_clone_device) String(nohost) Value(OMP_TARGET_SIMD_CLONE_NOHOST)
2274 Enum(target_simd_clone_device) String(any) Value(OMP_TARGET_SIMD_CLONE_ANY)
2277 Common Var(flag_opt_info) Optimization
2278 Enable all optimization info dumps on stderr.
2281 Common Joined RejectNegative Var(common_deferred_options) Defer
2282 -fopt-info[-<type>=filename] Dump compiler optimization details.
2284 fsave-optimization-record
2285 Common Var(flag_save_optimization_record) Optimization
2286 Write a SRCFILE.opt-record.json file detailing what optimizations were performed.
2288 foptimize-register-move
2290 Does nothing. Preserved for backward compatibility.
2292 foptimize-sibling-calls
2293 Common Var(flag_optimize_sibling_calls) Optimization
2294 Optimize sibling and tail recursive calls.
2297 Common Var(flag_partial_inlining) Optimization
2298 Perform partial inlining.
2301 Common Var(pre_ipa_mem_report)
2302 Report on memory allocation before interprocedural optimization.
2304 fpost-ipa-mem-report
2305 Common Var(post_ipa_mem_report)
2306 Report on memory allocation before interprocedural optimization.
2309 Common Var(flag_pack_struct) Optimization
2310 Pack structure members together without holes.
2313 Common RejectNegative Joined UInteger Optimization
2314 -fpack-struct=<number> Set initial maximum structure member alignment.
2317 Common Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
2318 Return small aggregates in memory, not registers.
2321 Common Var(flag_peel_loops) Optimization
2322 Perform loop peeling.
2325 Common Var(flag_no_peephole,0) Optimization
2326 Enable machine specific peephole optimizations.
2329 Common Var(flag_peephole2) Optimization
2330 Enable an RTL peephole pass before sched2.
2333 Common Var(flag_pic,2) Negative(fPIE) Init(-1)
2334 Generate position-independent code if possible (large mode).
2337 Common Var(flag_pie,2) Negative(fpic) Init(-1)
2338 Generate position-independent code for executables if possible (large mode).
2341 Common Var(flag_pic,1) Negative(fpie) Init(-1)
2342 Generate position-independent code if possible (small mode).
2345 Common Var(flag_pie,1) Negative(fPIC) Init(-1)
2346 Generate position-independent code for executables if possible (small mode).
2349 Common Var(flag_plt) Init(1) Optimization
2350 Use PLT for PIC calls (-fno-plt: load the address from GOT at call site).
2353 Common Joined RejectNegative Var(common_deferred_options) Defer
2354 Specify a plugin to load.
2357 Common Joined RejectNegative Var(common_deferred_options) Defer
2358 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>.
2360 fpredictive-commoning
2361 Common Var(flag_predictive_commoning) Optimization
2362 Run predictive commoning optimization.
2364 fprefetch-loop-arrays
2365 Common Var(flag_prefetch_loop_arrays) Init(-1) Optimization
2366 Generate prefetch instructions, if available, for arrays in loops.
2369 Common Var(profile_flag)
2370 Enable basic program profiling code.
2373 Common Var(profile_abs_path_flag)
2374 Generate absolute source path names for gcov.
2377 Common Var(profile_arc_flag)
2378 Insert arc-based program profiling code.
2381 Common Joined RejectNegative Var(profile_data_prefix)
2382 Set the top-level directory for storing the profile data.
2383 The default is 'pwd'.
2386 Common Joined RejectNegative Var(profile_note_location)
2387 Select the name for storing the profile note file.
2390 Common Var(flag_profile_correction)
2391 Enable correction of flow inconsistent profile data input.
2394 Common Joined RejectNegative Enum(profile_update) Var(flag_profile_update) Init(PROFILE_UPDATE_SINGLE)
2395 -fprofile-update=[single|atomic|prefer-atomic] Set the profile update method.
2397 fprofile-filter-files=
2398 Common Joined RejectNegative Var(flag_profile_filter_files)
2399 Instrument only functions from files whose name matches any of the regular expressions (separated by semi-colons).
2401 fprofile-exclude-files=
2402 Common Joined RejectNegative Var(flag_profile_exclude_files)
2403 Instrument only functions from files whose name does not match any of the regular expressions (separated by semi-colons).
2406 Name(profile_reproducibility) Type(enum profile_reproducibility) UnknownError(unknown profile reproducibility method %qs)
2409 Enum(profile_reproducibility) String(serial) Value(PROFILE_REPRODUCIBILITY_SERIAL)
2412 Enum(profile_reproducibility) String(parallel-runs) Value(PROFILE_REPRODUCIBILITY_PARALLEL_RUNS)
2415 Enum(profile_reproducibility) String(multithreaded) Value(PROFILE_REPRODUCIBILITY_MULTITHREADED)
2417 fprofile-reproducible=
2418 Common Joined RejectNegative Var(flag_profile_reproducible) Enum(profile_reproducibility) Init(PROFILE_REPRODUCIBILITY_SERIAL)
2419 -fprofile-reproducible=[serial|parallel-runs|multithreaded] Control level of reproducibility of profile gathered by -fprofile-generate.
2422 Name(profile_update) Type(enum profile_update) UnknownError(unknown profile update method %qs)
2425 Enum(profile_update) String(single) Value(PROFILE_UPDATE_SINGLE)
2428 Enum(profile_update) String(atomic) Value(PROFILE_UPDATE_ATOMIC)
2431 Enum(profile_update) String(prefer-atomic) Value(PROFILE_UPDATE_PREFER_ATOMIC)
2433 fprofile-prefix-path=
2434 Common Joined RejectNegative Var(profile_prefix_path)
2435 Remove prefix from absolute path before mangling name for -fprofile-generate= and -fprofile-use=.
2437 fprofile-prefix-map=
2438 Common Joined RejectNegative Var(common_deferred_options) Defer
2439 -fprofile-prefix-map=<old>=<new> Map one directory name to another in GCOV coverage result.
2443 Enable common options for generating profile info for profile feedback directed optimizations.
2446 Common Joined RejectNegative
2447 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=.
2449 fprofile-info-section
2450 Common RejectNegative
2451 Register the profile information in the .gcov_info section instead of using a constructor/destructor.
2453 fprofile-info-section=
2454 Common Joined RejectNegative Var(profile_info_section)
2455 Register the profile information in the specified section instead of using a constructor/destructor.
2457 fprofile-partial-training
2458 Common Var(flag_profile_partial_training) Optimization
2459 Do not assume that functions never executed during the train run are cold.
2462 Common Var(flag_profile_use)
2463 Enable common options for performing profile feedback directed optimizations.
2466 Common Joined RejectNegative
2467 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=.
2470 Common Var(flag_profile_values)
2471 Insert code to profile values of expressions.
2474 Common Var(profile_report)
2475 Report on consistency of profile.
2477 fprofile-reorder-functions
2478 Common Var(flag_profile_reorder_functions) Optimization
2479 Enable function reordering that improves code placement.
2481 fpatchable-function-entry=
2482 Common Var(flag_patchable_function_entry) Joined Optimization
2483 Insert NOP instructions at each function entry.
2486 Common Var(common_deferred_options) Defer
2489 Common Joined RejectNegative Var(common_deferred_options) Defer
2490 -frandom-seed=<string> Make compile reproducible using <string>.
2492 ; This switch causes the command line that was used to create an
2493 ; object file to be recorded into the object file. The exact format
2494 ; of this recording is target and binary file format dependent.
2495 ; It is related to the -fverbose-asm switch, but that switch only
2496 ; records information in the assembler output file as comments, so
2497 ; they never reach the object file.
2498 frecord-gcc-switches
2499 Common Var(flag_record_gcc_switches)
2500 Record gcc command line switches in the object file.
2503 Common Var(flag_pcc_struct_return,0) Optimization
2504 Return small aggregates in registers.
2508 Does nothing. Preserved for backward compatibility.
2511 Common Var(flag_lifetime_dse,2) Init(2) Optimization
2512 Tell DSE that the storage for a C++ object is dead when the constructor
2513 starts and when the destructor finishes.
2516 Common Joined RejectNegative UInteger Var(flag_lifetime_dse) Optimization IntegerRange(0, 2)
2519 Common RejectNegative Alias(flive-patching=,inline-clone) Optimization
2522 Common Joined RejectNegative Enum(live_patching_level) Var(flag_live_patching) Init(LIVE_PATCHING_NONE) Optimization
2523 -flive-patching=[inline-only-static|inline-clone] Control IPA
2524 optimizations to provide a safe compilation for live-patching. At the same
2525 time, provides multiple-level control on the enabled IPA optimizations.
2528 Name(live_patching_level) Type(enum live_patching_level) UnknownError(unknown Live-Patching Level %qs)
2531 Enum(live_patching_level) String(inline-only-static) Value(LIVE_PATCHING_INLINE_ONLY_STATIC)
2534 Enum(live_patching_level) String(inline-clone) Value(LIVE_PATCHING_INLINE_CLONE)
2537 Common Var(flag_allocation_dce) Init(1) Optimization
2538 Tell DCE to remove unused C++ allocations.
2540 flive-range-shrinkage
2541 Common Var(flag_live_range_shrinkage) Init(0) Optimization
2542 Relief of register pressure through live range shrinkage.
2545 Common Var(flag_rename_registers) Optimization EnabledBy(funroll-loops)
2546 Perform a register renaming optimization pass.
2549 Common Var(flag_schedule_fusion) Init(2) Optimization
2550 Perform a target dependent instruction fusion optimization pass.
2553 Common Var(flag_reorder_blocks) Optimization
2554 Reorder basic blocks to improve code placement.
2556 freorder-blocks-algorithm=
2557 Common Joined RejectNegative Enum(reorder_blocks_algorithm) Var(flag_reorder_blocks_algorithm) Init(REORDER_BLOCKS_ALGORITHM_SIMPLE) Optimization
2558 -freorder-blocks-algorithm=[simple|stc] Set the used basic block reordering algorithm.
2561 Name(reorder_blocks_algorithm) Type(enum reorder_blocks_algorithm) UnknownError(unknown basic block reordering algorithm %qs)
2564 Enum(reorder_blocks_algorithm) String(simple) Value(REORDER_BLOCKS_ALGORITHM_SIMPLE)
2567 Enum(reorder_blocks_algorithm) String(stc) Value(REORDER_BLOCKS_ALGORITHM_STC)
2569 freorder-blocks-and-partition
2570 Common Var(flag_reorder_blocks_and_partition) Optimization
2571 Reorder basic blocks and partition into hot and cold sections.
2574 Common Var(flag_reorder_functions) Optimization
2575 Reorder functions to improve code placement.
2577 frerun-cse-after-loop
2578 Common Var(flag_rerun_cse_after_loop) Optimization
2579 Add a common subexpression elimination pass after loop optimizations.
2583 Does nothing. Preserved for backward compatibility.
2586 Common Var(flag_rounding_math) Optimization SetByCombined
2587 Disable optimizations that assume default FP rounding behavior.
2590 Common Var(flag_schedule_interblock) Init(1) Optimization
2591 Enable scheduling across basic blocks.
2594 Common Var(flag_sched_pressure) Init(0) Optimization
2595 Enable register pressure sensitive insn scheduling.
2598 Common Var(flag_schedule_speculative) Init(1) Optimization
2599 Allow speculative motion of non-loads.
2602 Common Var(flag_schedule_speculative_load) Optimization
2603 Allow speculative motion of some loads.
2605 fsched-spec-load-dangerous
2606 Common Var(flag_schedule_speculative_load_dangerous) Optimization
2607 Allow speculative motion of more loads.
2610 Common RejectNegative Joined UInteger Var(sched_verbose_param) Init(1)
2611 -fsched-verbose=<number> Set the verbosity level of the scheduler.
2613 fsched2-use-superblocks
2614 Common Var(flag_sched2_use_superblocks) Optimization
2615 If scheduling post reload, do superblock scheduling.
2619 Does nothing. Preserved for backward compatibility.
2622 Common Var(flag_schedule_insns) Optimization
2623 Reschedule instructions before register allocation.
2626 Common Var(flag_schedule_insns_after_reload) Optimization
2627 Reschedule instructions after register allocation.
2629 ; This flag should be on when a target implements non-trivial
2630 ; scheduling hooks, maybe saving some information for its own sake.
2631 ; On IA64, for example, this is used for correct bundling.
2632 fselective-scheduling
2633 Common Var(flag_selective_scheduling) Optimization
2634 Schedule instructions using selective scheduling algorithm.
2636 fselective-scheduling2
2637 Common Var(flag_selective_scheduling2) Optimization
2638 Run selective scheduling after reload.
2641 Common Undocumented Joined Var(flag_self_test)
2642 Run self-tests, using the given path to locate test files.
2644 fsel-sched-pipelining
2645 Common Var(flag_sel_sched_pipelining) Init(0) Optimization
2646 Perform software pipelining of inner loops during selective scheduling.
2648 fsel-sched-pipelining-outer-loops
2649 Common Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
2650 Perform software pipelining of outer loops during selective scheduling.
2652 fsel-sched-reschedule-pipelined
2653 Common Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
2654 Reschedule pipelined regions without pipelining.
2656 fsemantic-interposition
2657 Common Var(flag_semantic_interposition) Init(1) Optimization
2658 Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker.
2660 ; sched_stalled_insns means that insns can be moved prematurely from the queue
2661 ; of stalled insns into the ready list.
2662 fsched-stalled-insns
2663 Common Var(flag_sched_stalled_insns) Optimization UInteger
2664 Allow premature scheduling of queued insns.
2666 fsched-stalled-insns=
2667 Common RejectNegative Joined UInteger Optimization
2668 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled.
2670 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
2671 ; be examined for a dependency on a stalled insn that is candidate for
2672 ; premature removal from the queue of stalled insns into the ready list (has
2673 ; an effect only if the flag 'sched_stalled_insns' is set).
2674 fsched-stalled-insns-dep
2675 Common Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
2676 Set dependence distance checking in premature scheduling of queued insns.
2678 fsched-stalled-insns-dep=
2679 Common RejectNegative Joined UInteger Optimization
2680 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns.
2682 fsched-group-heuristic
2683 Common Var(flag_sched_group_heuristic) Init(1) Optimization
2684 Enable the group heuristic in the scheduler.
2686 fsched-critical-path-heuristic
2687 Common Var(flag_sched_critical_path_heuristic) Init(1) Optimization
2688 Enable the critical path heuristic in the scheduler.
2690 fsched-spec-insn-heuristic
2691 Common Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
2692 Enable the speculative instruction heuristic in the scheduler.
2694 fsched-rank-heuristic
2695 Common Var(flag_sched_rank_heuristic) Init(1) Optimization
2696 Enable the rank heuristic in the scheduler.
2698 fsched-last-insn-heuristic
2699 Common Var(flag_sched_last_insn_heuristic) Init(1) Optimization
2700 Enable the last instruction heuristic in the scheduler.
2702 fsched-dep-count-heuristic
2703 Common Var(flag_sched_dep_count_heuristic) Init(1) Optimization
2704 Enable the dependent count heuristic in the scheduler.
2707 Common Var(flag_section_anchors) Optimization
2708 Access data in the same section from shared anchor points.
2712 Does nothing. Preserved for backward compatibility.
2716 Does nothing. Preserved for backward compatibility.
2719 Common Var(flag_ree) Init(0) Optimization
2720 Turn on Redundant Extensions Elimination pass.
2723 Common Var(flag_show_column) Init(1)
2724 Show column numbers in diagnostics, when available. Default on.
2727 Common Var(flag_shrink_wrap) Optimization
2728 Emit function prologues only before parts of the function that need it,
2729 rather than at the top of the function.
2731 fshrink-wrap-separate
2732 Common Var(flag_shrink_wrap_separate) Init(1) Optimization
2733 Shrink-wrap parts of the prologue and epilogue separately.
2736 Common Var(flag_signaling_nans) Optimization SetByCombined
2737 Disable optimizations observable by IEEE signaling NaNs.
2740 Common Var(flag_signed_zeros) Init(1) Optimization SetByCombined
2741 Disable floating point optimizations that ignore the IEEE signedness of zero.
2743 fsingle-precision-constant
2744 Common Var(flag_single_precision_constant) Optimization
2745 Convert floating point constants to single precision constants.
2747 fsplit-ivs-in-unroller
2748 Common Var(flag_split_ivs_in_unroller) Init(1) Optimization
2749 Split lifetimes of induction variables when loops are unrolled.
2752 Common Var(flag_split_stack) Init(-1)
2753 Generate discontiguous stack frames.
2756 Common Var(flag_split_wide_types) Optimization
2757 Split wide types into independent registers.
2759 fsplit-wide-types-early
2760 Common Var(flag_split_wide_types_early) Optimization
2761 Split wide types into independent registers earlier.
2764 Common Var(flag_ssa_backprop) Init(1) Optimization
2765 Enable backward propagation of use properties at the SSA level.
2768 Common Var(flag_ssa_phiopt) Optimization
2769 Optimize conditional patterns using SSA PHI nodes.
2772 Common Var(flag_stdarg_opt) Init(1) Optimization
2773 Optimize amount of stdarg registers saved to stack at start of function.
2775 fvariable-expansion-in-unroller
2776 Common Var(flag_variable_expansion_in_unroller) Optimization
2777 Apply variable expansion when loops are unrolled.
2780 Common RejectNegative Joined Optimization
2781 -fstack-check=[no|generic|specific] Insert stack checking code into the program.
2784 Common Alias(fstack-check=, specific, no)
2785 Insert stack checking code into the program. Same as -fstack-check=specific.
2787 fstack-clash-protection
2788 Common Var(flag_stack_clash_protection) Optimization
2789 Insert code to probe each page of stack space as it is allocated to protect
2790 from stack-clash style attacks.
2793 Common Var(common_deferred_options) Defer
2795 fstack-limit-register=
2796 Common RejectNegative Joined Var(common_deferred_options) Defer
2797 -fstack-limit-register=<register> Trap if the stack goes past <register>.
2799 fstack-limit-symbol=
2800 Common RejectNegative Joined Var(common_deferred_options) Defer
2801 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>.
2804 Common Var(flag_stack_protect, 1) Init(-1) Optimization
2805 Use propolice as a stack protection method.
2807 fstack-protector-all
2808 Common RejectNegative Var(flag_stack_protect, 2) Init(-1) Optimization
2809 Use a stack protection method for every function.
2811 fstack-protector-strong
2812 Common RejectNegative Var(flag_stack_protect, 3) Init(-1) Optimization
2813 Use a smart stack protection method for certain functions.
2815 fstack-protector-explicit
2816 Common RejectNegative Var(flag_stack_protect, 4) Optimization
2817 Use stack protection method only for functions with the stack_protect attribute.
2820 Common RejectNegative Var(flag_stack_usage)
2821 Output stack usage information on a per-function basis.
2825 Does nothing. Preserved for backward compatibility.
2827 ; Nonzero if we should do (language-dependent) alias analysis.
2828 ; Typically, this analysis will assume that expressions of certain
2829 ; types do not alias expressions of certain other types. Only used
2830 ; if alias analysis (in general) is enabled.
2832 Common Var(flag_strict_aliasing) Optimization
2833 Assume strict aliasing rules apply.
2837 Treat signed overflow as undefined. Negated as -fwrapv -fwrapv-pointer.
2840 Common Var(flag_sync_libcalls) Init(1)
2841 Implement __atomic operations via libcalls to legacy __sync functions.
2844 Common Var(flag_syntax_only)
2845 Check for syntax errors, then stop.
2848 Common Var(flag_test_coverage)
2849 Create data files needed by \"gcov\".
2852 Common Var(flag_thread_jumps) Optimization
2853 Perform jump threading optimizations.
2856 Common Var(time_report)
2857 Report the time taken by each compiler pass.
2859 ftime-report-details
2860 Common Var(time_report_details)
2861 Record times taken by sub-phases separately.
2864 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2865 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model.
2868 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2871 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2874 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2877 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2880 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2883 Common Var(flag_toplevel_reorder) Init(2) Optimization
2884 Reorder top level functions, variables, and asms.
2887 Common Var(flag_tracer) Optimization
2888 Perform superblock formation via tail duplication.
2891 Common Var(flag_trampolines) Init(0)
2892 For targets that normally need trampolines for nested functions, always
2893 generate them instead of using descriptors.
2895 ; Zero means that floating-point math operations cannot generate a
2896 ; (user-visible) trap. This is the case, for example, in nonstop
2897 ; IEEE 754 arithmetic.
2899 Common Var(flag_trapping_math) Init(1) Optimization SetByCombined
2900 Assume floating-point operations can trap.
2903 Common Var(flag_trapv) Optimization
2904 Trap for signed overflow in addition, subtraction and multiplication.
2907 Common Var(flag_tree_ccp) Optimization
2908 Enable SSA-CCP optimization on trees.
2911 Common Var(flag_tree_bit_ccp) Optimization
2912 Enable SSA-BIT-CCP optimization on trees.
2916 Does nothing. Preserved for backward compatibility.
2919 Common Var(flag_tree_ch) Optimization
2920 Enable loop header copying on trees.
2922 ftree-coalesce-inlined-vars
2923 Common Ignore RejectNegative
2924 Does nothing. Preserved for backward compatibility.
2927 Common Var(flag_tree_coalesce_vars) Optimization
2928 Enable SSA coalescing of user variables.
2932 Does nothing. Preserved for backward compatibility.
2935 Common Var(flag_tree_copy_prop) Optimization
2936 Enable copy propagation on trees.
2938 ftree-store-copy-prop
2940 Does nothing. Preserved for backward compatibility.
2943 Common Var(flag_tree_cselim) Optimization
2944 Transform condition stores into unconditional ones.
2946 ftree-switch-conversion
2947 Common Var(flag_tree_switch_conversion) Optimization
2948 Perform conversions of switch initializations.
2951 Common Var(flag_tree_dce) Optimization
2952 Enable SSA dead code elimination optimization on trees.
2954 ftree-dominator-opts
2955 Common Var(flag_tree_dom) Optimization
2956 Enable dominator optimizations.
2959 Common Var(flag_tree_tail_merge) Optimization
2960 Enable tail merging on trees.
2963 Common Var(flag_tree_dse) Optimization
2964 Enable dead store elimination.
2967 Common Var(flag_tree_forwprop) Init(1) Optimization
2968 Enable forward propagation on trees.
2971 Common Var(flag_tree_fre) Optimization
2972 Enable Full Redundancy Elimination (FRE) on trees.
2975 Common Var(flag_optimize_strlen) Optimization
2976 Enable string length optimizations on trees.
2978 fisolate-erroneous-paths-dereference
2979 Common Var(flag_isolate_erroneous_paths_dereference) Optimization
2980 Detect paths that trigger erroneous or undefined behavior due to
2981 dereferencing a null pointer. Isolate those paths from the main control
2982 flow and turn the statement with erroneous or undefined behavior into a trap.
2984 fisolate-erroneous-paths-attribute
2985 Common Var(flag_isolate_erroneous_paths_attribute) Optimization
2986 Detect paths that trigger erroneous or undefined behavior due to a null value
2987 being used in a way forbidden by a returns_nonnull or nonnull
2988 attribute. Isolate those paths from the main control flow and turn the
2989 statement with erroneous or undefined behavior into a trap.
2991 ftree-loop-distribution
2992 Common Var(flag_tree_loop_distribution) Optimization
2993 Enable loop distribution on trees.
2995 ftree-loop-distribute-patterns
2996 Common Var(flag_tree_loop_distribute_patterns) Optimization
2997 Enable loop distribution for patterns transformed into a library call.
3000 Common Var(flag_tree_loop_im) Init(1) Optimization
3001 Enable loop invariant motion on trees.
3004 Common Alias(floop-nest-optimize)
3005 Enable loop nest transforms. Same as -floop-nest-optimize.
3008 Common Var(flag_tree_loop_ivcanon) Init(1) Optimization
3009 Create canonical induction variables in loops.
3012 Common Var(flag_tree_loop_optimize) Init(1) Optimization
3013 Enable loop optimizations on tree level.
3015 ftree-parallelize-loops=
3016 Common Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) Optimization
3017 -ftree-parallelize-loops=<number> Enable automatic parallelization of loops.
3020 Common Var(flag_tree_phiprop) Init(1) Optimization
3021 Enable hoisting loads from conditional pointers.
3024 Common Var(flag_tree_pre) Optimization
3025 Enable SSA-PRE optimization on trees.
3028 Common Var(flag_tree_partial_pre) Optimization
3029 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination.
3032 Common Var(flag_tree_pta) Optimization
3033 Perform function-local points-to analysis on trees.
3036 Common Var(flag_tree_reassoc) Init(1) Optimization
3037 Enable reassociation on tree level.
3041 Does nothing. Preserved for backward compatibility.
3044 Common Var(flag_tree_sink) Optimization
3045 Enable SSA code sinking on trees.
3048 Common Var(flag_tree_slsr) Optimization
3049 Perform straight-line strength reduction.
3052 Common Var(flag_tree_sra) Optimization
3053 Perform scalar replacement of aggregates.
3056 Common Var(flag_tree_ter) Optimization
3057 Replace temporary expressions in the SSA->normal pass.
3060 Common Var(flag_tree_live_range_split) Optimization
3061 Perform live range splitting during the SSA->normal pass.
3064 Common Var(flag_tree_vrp) Init(0) Optimization
3065 Perform Value Range Propagation on trees.
3068 Common Var(flag_split_paths) Init(0) Optimization
3069 Split paths leading to loop backedges.
3071 funconstrained-commons
3072 Common Var(flag_unconstrained_commons) Optimization
3073 Assume common declarations may be overridden with ones with a larger
3077 Common Var(flag_unit_at_a_time) Init(1)
3078 Compile whole compilation unit at a time.
3081 Common Var(flag_unreachable_traps) Optimization
3082 Trap on __builtin_unreachable instead of using it for optimization.
3085 Common Var(flag_unroll_loops) Optimization EnabledBy(funroll-all-loops)
3086 Perform loop unrolling when iteration count is known.
3089 Common Var(flag_unroll_all_loops) Optimization
3090 Perform loop unrolling for all loops.
3092 funroll-completely-grow-size
3093 Undocumented Var(flag_cunroll_grow_size) Optimization
3094 ; Internal undocumented flag, allow size growth during complete unrolling
3096 ; Nonzero means that loop optimizer may assume that the induction variables
3097 ; that control loops do not overflow and that the loops with nontrivial
3098 ; exit condition are not infinite
3099 funsafe-loop-optimizations
3101 Does nothing. Preserved for backward compatibility.
3104 Common Var(flag_associative_math) SetByCombined Optimization
3105 Allow optimization for floating-point arithmetic which may change the
3106 result of the operation due to rounding.
3109 Common Var(flag_reciprocal_math) SetByCombined Optimization
3110 Same as -fassociative-math for expressions which include division.
3112 ; Nonzero means that unsafe floating-point math optimizations are allowed
3113 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
3114 ; are allowed to assume that their arguments and results are "normal"
3115 ; (e.g., nonnegative for SQRT).
3116 funsafe-math-optimizations
3117 Common Var(flag_unsafe_math_optimizations) Optimization SetByCombined
3118 Allow math optimizations that may violate IEEE or ISO standards.
3121 Common Var(flag_unswitch_loops) Optimization
3122 Perform loop unswitching.
3125 Common Var(flag_split_loops) Optimization
3126 Perform loop splitting.
3128 fversion-loops-for-strides
3129 Common Var(flag_version_loops_for_strides) Optimization
3130 Version loops based on whether indices have a stride of one.
3133 Common Var(flag_unwind_tables) Optimization
3134 Just generate unwind tables for exception handling.
3137 Common Driver Negative(fuse-ld=gold)
3138 Use the bfd linker instead of the default linker.
3141 Common Driver Negative(fuse-ld=bfd)
3142 Use the gold linker instead of the default linker.
3145 Common Driver Negative(fuse-ld=lld)
3146 Use the lld LLVM linker instead of the default linker.
3149 Common Driver Negative(fuse-ld=mold)
3150 Use the Modern linker (MOLD) linker instead of the default linker.
3153 Common Undocumented Var(flag_use_linker_plugin)
3155 ; Positive if we should track variables, negative if we should run
3156 ; the var-tracking pass only to discard debug annotations, zero if
3157 ; we're not to run it.
3159 Common Var(flag_var_tracking) PerFunction EnabledBy(fvar-tracking-uninit)
3160 Perform variable tracking.
3162 ; Positive if we should track variables at assignments, negative if
3163 ; we should run the var-tracking pass only to discard debug
3165 fvar-tracking-assignments
3166 Common Var(flag_var_tracking_assignments) PerFunction
3167 Perform variable tracking by annotating assignments.
3169 ; Nonzero if we should toggle flag_var_tracking_assignments after
3170 ; processing options and computing its default. */
3171 fvar-tracking-assignments-toggle
3172 Common Var(flag_var_tracking_assignments_toggle) PerFunction
3173 Toggle -fvar-tracking-assignments.
3175 ; Positive if we should track uninitialized variables, negative if
3176 ; we should run the var-tracking pass only to discard debug
3178 fvar-tracking-uninit
3179 Common Var(flag_var_tracking_uninit) PerFunction
3180 Perform variable tracking and also tag variables that are uninitialized.
3182 ; Alias to enable both -ftree-loop-vectorize and -ftree-slp-vectorize.
3184 Common Var(flag_tree_vectorize) Optimization
3185 Enable vectorization on trees.
3187 ftree-vectorizer-verbose=
3188 Common Joined RejectNegative Ignore
3189 Does nothing. Preserved for backward compatibility.
3191 ftree-loop-vectorize
3192 Common Var(flag_tree_loop_vectorize) Optimization EnabledBy(ftree-vectorize)
3193 Enable loop vectorization on trees.
3196 Common Var(flag_tree_slp_vectorize) Optimization EnabledBy(ftree-vectorize)
3197 Enable basic block vectorization (SLP) on trees.
3200 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization
3201 -fvect-cost-model=[unlimited|dynamic|cheap|very-cheap] Specifies the cost model for vectorization.
3204 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization
3205 -fsimd-cost-model=[unlimited|dynamic|cheap|very-cheap] Specifies the vectorization cost model for code marked with a simd directive.
3208 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
3211 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
3214 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
3217 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
3220 Enum(vect_cost_model) String(very-cheap) Value(VECT_COST_MODEL_VERY_CHEAP)
3223 Common Alias(fvect-cost-model=,dynamic,unlimited)
3224 Enables the dynamic vectorizer cost model. Preserved for backward compatibility.
3226 ftree-vect-loop-version
3228 Does nothing. Preserved for backward compatibility.
3231 Common Var(flag_tree_scev_cprop) Init(1) Optimization
3232 Enable copy propagation of scalar-evolution information.
3234 ftrivial-auto-var-init=
3235 Common Joined RejectNegative Enum(auto_init_type) Var(flag_auto_var_init) Init(AUTO_INIT_UNINITIALIZED) Optimization
3236 -ftrivial-auto-var-init=[uninitialized|pattern|zero] Add initializations to automatic variables.
3239 Name(auto_init_type) Type(enum auto_init_type) UnknownError(unrecognized automatic variable initialization type %qs)
3242 Enum(auto_init_type) String(uninitialized) Value(AUTO_INIT_UNINITIALIZED)
3245 Enum(auto_init_type) String(pattern) Value(AUTO_INIT_PATTERN)
3248 Enum(auto_init_type) String(zero) Value(AUTO_INIT_ZERO)
3250 ; -fverbose-asm causes extra commentary information to be produced in
3251 ; the generated assembly code (to make it more readable). This option
3252 ; is generally only of use to those who actually need to read the
3253 ; generated assembly code (perhaps while debugging the compiler itself).
3254 ; -fno-verbose-asm, the default, causes the extra information
3255 ; to not be added and is useful when comparing two assembler files.
3257 Common Var(flag_verbose_asm)
3258 Add extra commentary to assembler output.
3261 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
3262 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility.
3265 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
3268 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
3271 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
3274 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
3277 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
3280 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
3281 Validate vtable pointers before using them.
3284 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
3287 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
3290 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
3293 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
3296 Common Var(flag_vtv_counts)
3297 Output vtable verification counters.
3300 Common Var(flag_vtv_debug)
3301 Output vtable verification pointer sets information.
3304 Common Var(flag_value_profile_transformations) Optimization
3305 Use expression value profiles in optimizations.
3308 Common Var(flag_web) Optimization EnabledBy(funroll-loops)
3309 Construct webs and split unrelated uses of single variable.
3311 ftree-builtin-call-dce
3312 Common Var(flag_tree_builtin_call_dce) Init(0) Optimization
3313 Enable conditional dead code elimination for builtin calls.
3316 Common Var(flag_whole_program) Init(0)
3317 Perform whole program optimizations.
3320 Common Var(flag_wrapv_pointer) Optimization
3321 Assume pointer overflow wraps around.
3324 Common Var(flag_wrapv) Optimization
3325 Assume signed arithmetic overflow wraps around.
3327 fzero-initialized-in-bss
3328 Common Var(flag_zero_initialized_in_bss) Init(1)
3329 Put zero initialized data in the bss section.
3331 fzero-call-used-regs=
3332 Common RejectNegative Joined
3333 Clear call-used registers upon function return.
3336 Common Driver RejectNegative JoinedOrMissing
3337 Generate debug information in default format.
3340 Common Driver Var(dwarf2out_as_loc_support)
3341 Assume assembler support for (DWARF2+) .loc directives.
3344 Common Driver Var(dwarf2out_as_locview_support)
3345 Assume assembler support for view in (DWARF2+) .loc directives.
3348 Common Driver JoinedOrMissing
3349 Generate debug information in CodeView format.
3352 Common Driver WarnRemoved
3353 Does nothing. Preserved for backward compatibility.
3356 Common Driver WarnRemoved
3357 Does nothing. Preserved for backward compatibility.
3360 Common Driver WarnRemoved
3361 Does nothing. Preserved for backward compatibility.
3364 Common Driver WarnRemoved
3365 Does nothing. Preserved for backward compatibility.
3368 Common Driver Var(debug_column_info,1) Init(1)
3369 Record DW_AT_decl_column and DW_AT_call_column in DWARF.
3371 ; The CTF generation process feeds off DWARF dies. This option implicitly
3372 ; updates the debug_info_level to DINFO_LEVEL_NORMAL.
3374 Common Driver RejectNegative JoinedOrMissing
3375 Generate CTF debug information at default level.
3378 Common Driver RejectNegative JoinedOrMissing
3379 Generate BTF debug information at default level.
3382 Common Driver JoinedOrMissing RejectNegative
3383 Generate debug information in default version of DWARF format.
3386 Common Driver Joined UInteger Var(dwarf_version) Init(DWARF_VERSION_DEFAULT) RejectNegative
3387 Generate debug information in DWARF v2 (or later) format.
3390 Common Driver Var(dwarf_offset_size,4) Init(4) RejectNegative
3391 Use 32-bit DWARF format when emitting DWARF debug information.
3394 Common Driver Var(dwarf_offset_size,8) RejectNegative
3395 Use 64-bit DWARF format when emitting DWARF debug information.
3398 Common Driver JoinedOrMissing RejectNegative
3399 Generate debug information in default extended format.
3402 Common Driver Var(debug_inline_points)
3403 Generate extended entry point information for inlined functions.
3405 ginternal-reset-location-views
3406 Common Driver Var(debug_internal_reset_location_views) Init(2)
3407 Compute locview reset points based on insn length estimates.
3410 RejectNegative Joined Undocumented
3411 ; Catch the gno- prefix, so it doesn't backtrack to g<level>.
3414 Common Driver Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
3415 Don't generate DWARF pubnames and pubtypes sections.
3418 Common Driver Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
3419 Generate DWARF pubnames and pubtypes sections.
3422 Common Driver Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
3423 Generate DWARF pubnames and pubtypes sections with GNU extensions.
3425 grecord-gcc-switches
3426 Common Driver Var(dwarf_record_gcc_switches) Init(1)
3427 Record gcc command line switches in DWARF DW_AT_producer.
3430 Common Driver Var(dwarf_split_debug_info) Init(0)
3431 Generate debug information in separate .dwo files.
3434 Common Driver WarnRemoved
3435 Does nothing. Preserved for backward compatibility.
3438 Common Driver WarnRemoved
3439 Does nothing. Preserved for backward compatibility.
3441 gstatement-frontiers
3442 Common Driver Var(debug_nonbind_markers_p) PerFunction
3443 Emit progressive recommended breakpoint locations.
3446 Common Driver Var(dwarf_strict) Init(0)
3447 Don't emit DWARF additions beyond selected version.
3450 Common Driver Var(flag_describe_dies) Init(0)
3451 Add description attributes to some DWARF DIEs that have no name attribute.
3454 Common Driver Var(flag_gtoggle)
3455 Toggle debug information generation.
3457 gvariable-location-views
3458 Common Driver Var(debug_variable_location_views, 1)
3459 Augment variable location lists with progressive views.
3461 gvariable-location-views=incompat5
3462 Common Driver RejectNegative Var(debug_variable_location_views, -1) Init(2)
3465 Common Driver JoinedOrMissing RejectNegative
3466 Generate debug information in VMS format.
3469 Common Driver WarnRemoved
3470 Does nothing. Preserved for backward compatibility.
3473 Common Driver JoinedOrMissing WarnRemoved
3474 Does nothing. Preserved for backward compatibility.
3477 Name(compressed_debug_sections) Type(int)
3479 ; Since -gz= is completely handled in specs, the values aren't used and we
3480 ; assign arbitrary constants.
3482 Enum(compressed_debug_sections) String(none) Value(0)
3485 Enum(compressed_debug_sections) String(zlib) Value(1)
3488 Enum(compressed_debug_sections) String(zstd) Value(2)
3491 Enum(compressed_debug_sections) String(zlib-gnu) Value(3)
3495 Generate compressed debug sections.
3498 Common Driver RejectNegative Joined Enum(compressed_debug_sections)
3499 -gz=<format> Generate compressed debug sections in format <format>.
3502 Driver Joined Separate
3505 Common Joined Var(plugindir_string) Init(0)
3506 -iplugindir=<dir> Set <dir> to be the default plugin directory.
3509 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
3510 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory.
3513 Driver Joined Separate
3518 no-canonical-prefixes
3537 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
3538 -o <file> Place output into <file>.
3541 Common Var(profile_flag)
3542 Enable function profiling.
3545 Driver Var(pass_exit_codes)
3548 Common Alias(Wpedantic)
3551 Common Var(flag_pedantic_errors)
3552 Like -pedantic but issue them as errors.
3558 Driver Var(use_pipes)
3561 Driver JoinedOrMissing Var(print_file_name)
3563 print-libgcc-file-name
3566 print-multi-directory
3567 Driver Var(print_multi_directory)
3570 Driver Var(print_multi_lib)
3572 print-multi-os-directory
3573 Driver Var(print_multi_os_directory)
3576 Driver Var(print_multiarch)
3579 Driver JoinedOrMissing Var(print_prog_name)
3582 Driver Var(print_search_dirs)
3585 Driver Var(print_sysroot)
3587 print-sysroot-headers-suffix
3588 Driver Var(print_sysroot_headers_suffix)
3591 Common Var(quiet_flag) RejectDriver
3592 Do not display functions compiled or elapsed time.
3610 Driver Var(report_times)
3613 Driver JoinedOrMissing
3616 Driver Joined Separate
3620 ; C option, but driver must not handle as "-u ndef".
3623 Common Driver Var(verbose_flag)
3624 Enable verbose output.
3627 Common Var(version_flag) RejectDriver
3628 Display the compiler's version.
3631 Common Var(inhibit_warnings)
3635 Driver Separate Var(wrapper_string)
3638 Driver Joined Separate
3641 Driver RejectNegative Negative(static-pie)
3642 Create a shared library.
3648 Driver Separate Alias(specs=)
3661 ; Documented for Fortran, but always accepted by driver.
3665 ; Documented for Modula-2, but always accepted by driver.
3669 ; Documented for D, but always accepted by driver.
3673 ; Documented for Fortran, but always accepted by driver.
3680 ; Documented for Go, but always accepted by driver.
3701 Driver RejectNegative Negative(shared)
3702 Don't create a dynamically linked position independent executable.
3705 Driver RejectNegative Negative(no-pie)
3706 Create a dynamically linked position independent executable.
3709 Driver RejectNegative Negative(pie)
3710 Create a static position independent executable.
3713 Driver Joined Separate
3716 Common Var(flag_ipa_ra) Optimization
3717 Use caller save register across calls if possible.
3719 ; This comment is to ensure we retain the blank line above.