1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003-2018 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 incrmeental 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
62 ; Language specific warning pass for unused results.
64 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 two are really VEC(char_p,heap) *.
89 void *flag_instrument_functions_exclude_functions
92 void *flag_instrument_functions_exclude_files
94 ; Generic structs (e.g. templates not explicitly specialized)
95 ; may not have a compilation unit associated with them, and so
96 ; may need to be treated differently from ordinary structs.
98 ; Structs only handled by reference (indirectly), will also usually
99 ; not need as much debugging information.
102 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
105 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
107 ; True if we should exit after parsing options.
109 bool exit_after_options
111 ; Type(s) of debugging information we are producing (if any). See
112 ; flag-types.h for the definitions of the different possible types of
113 ; debugging information.
115 enum debug_info_type write_symbols = NO_DEBUG
117 ; Level of debugging information we are producing. See flag-types.h
118 ; for the definitions of the different possible levels.
120 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
122 ; Nonzero means use GNU-only extensions in the generated symbolic
123 ; debugging information. Currently, this only has an effect when
124 ; write_symbols is set to DBX_DEBUG or XCOFF_DEBUG.
126 bool use_gnu_debug_info_extensions
128 ; Original value of maximum field alignment in bytes, specified via
129 ; -fpack-struct=<value>.
131 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
133 ; Type of stack check.
135 enum stack_check_type flag_stack_check = NO_STACK_CHECK
137 ; True if stack usage information needs to be computed.
139 bool flag_stack_usage_info = false
141 ; -dA causes debug commentary information to be produced in
142 ; the generated assembly code (to make it more readable). This option
143 ; is generally only of use to those who actually need to read the
144 ; generated assembly code (perhaps while debugging the compiler itself).
145 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
146 ; to be a catchall for printing debug information in the assembler file.
150 ; How many NOP insns to place at each function entry by default
152 HOST_WIDE_INT function_entry_patch_area_size
154 ; And how far the real asm entry point is into this area
156 HOST_WIDE_INT function_entry_patch_area_start
158 ; Balance between GNAT encodings and standard DWARF to emit.
160 enum dwarf_gnat_encodings gnat_encodings = DWARF_GNAT_ENCODINGS_DEFAULT
162 ; -dP causes the rtl to be emitted as a comment in assembly.
164 int flag_dump_rtl_in_asm
166 ; Whether -da was passed (used only in handle_common_deferred_options).
168 bool flag_dump_all_passed
170 ; Other flags saying which kinds of debugging dump have been requested.
173 int rtl_dump_and_exit
176 int flag_print_asm_name
178 ; Name of top-level original source file (what was input to cpp).
179 ; This comes from the #-command at the beginning of the actual input.
180 ; If there isn't any there, then this is the cc1 input file name.
182 const char *main_input_filename
184 ; Pointer to base name in main_input_filename, with directories and a
185 ; single final extension removed, and the length of this base
189 const char *main_input_basename
192 int main_input_baselength
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_UNREACHABLE | SANITIZE_RETURN)
220 ; What the coverage sanitizers should instrument
222 unsigned int flag_sanitize_coverage
224 ; Flag whether a prefix has been added to dump_base_name
226 bool dump_base_name_prefixed = false
228 ; Flag whether HSA generation has been explicitely disabled
230 bool flag_disable_hsa = false
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 Common Separate Alias(dumpbase)
261 Common Separate Alias(dumpdir)
264 Driver Separate Alias(e)
267 Driver Joined Alias(e)
270 Common Warning Alias(Wextra)
273 Driver Separate Alias(Xassembler)
276 Driver JoinedOrMissing Alias(Xassembler)
279 Driver Separate Alias(Xlinker)
282 Driver JoinedOrMissing Alias(Xlinker)
285 Driver Separate Alias(u)
288 Driver Joined Alias(u)
291 Common Driver Var(help_flag)
292 Display this information.
295 Common Driver Report Joined
296 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params.
299 Driver Separate Alias(x)
302 Driver Joined Alias(x)
305 Driver Separate Alias(L)
308 Driver Joined Alias(L)
310 -no-canonical-prefixes
311 Driver Alias(no-canonical-prefixes)
313 -no-standard-libraries
314 Driver Alias(nostdlib)
317 Driver Var(no_sysroot_suffix)
326 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
329 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
332 Driver Alias(pass-exit-codes)
335 Common Alias(Wpedantic)
338 Common Alias(pedantic-errors)
344 Driver Alias(static-pie)
350 Driver Separate Alias(B)
353 Driver JoinedOrMissing Alias(B)
359 Driver Separate Alias(print-file-name=)
362 Driver JoinedOrMissing Alias(print-file-name=)
364 -print-libgcc-file-name
365 Driver Alias(print-libgcc-file-name)
367 -print-multi-directory
368 Driver Alias(print-multi-directory)
371 Driver Alias(print-multi-lib)
373 -print-multi-os-directory
374 Driver Alias(print-multi-os-directory)
377 Driver Alias(print-multiarch)
380 Driver Separate Alias(print-prog-name=)
383 Driver JoinedOrMissing Alias(print-prog-name=)
386 Driver Alias(print-search-dirs)
389 Driver Alias(print-sysroot)
391 -print-sysroot-headers-suffix
392 Driver Alias(print-sysroot-headers-suffix)
398 Driver Alias(save-temps)
404 Driver Separate Alias(specs=)
407 Driver Joined Alias(specs=)
413 Driver Alias(symbolic)
417 Alias for --help=target.
425 ;; The driver used to convert options such as --help into forms such
426 ;; as -fhelp; the following four entries are for compatibility with
427 ;; any direct uses of those (undocumented) -f forms
429 Common Driver Alias(-help)
432 Common Driver Joined Alias(-help=)
435 Common Driver Alias(-target-help)
438 Common Driver Alias(-version)
442 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters.
445 Common Joined Alias(-param)
448 Driver Separate Alias(-sysroot=)
451 Driver JoinedOrMissing
457 Driver Joined Separate
463 Driver Joined Separate
469 Common JoinedOrMissing Optimization
470 -O<number> Set optimization level to <number>.
474 Optimize for space rather than speed.
478 Optimize for speed disregarding exact standards compliance.
482 Optimize for debugging experience rather than speed or size.
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 Var(warn_array_bounds) Warning
543 Warn if an array is accessed out of bounds.
546 Common Joined RejectNegative UInteger Var(warn_array_bounds) Warning IntegerRange(0, 2)
547 Warn if an array is accessed out of bounds.
550 Common Var(warn_attributes) Init(1) Warning
551 Warn about inappropriate attribute usage.
554 Common Var(warn_attributes) Init(1) Warning
555 Warn about type safety and similar errors in attribute alias and related.
558 Common Var(warn_cannot_profile) Init(1) Warning
559 Warn when profiling instrumentation was requested, but could not be applied to
563 Common Var(warn_cast_align) Warning
564 Warn about pointer casts which increase alignment.
567 Common Var(warn_cast_align,2) Warning
568 Warn about pointer casts which increase alignment.
571 Common Var(warn_cpp) Init(1) Warning
572 Warn when a #warning directive is encountered.
575 Common Var(warn_attribute_warning) Init(1) Warning
576 Warn about uses of __attribute__((warning)) declarations.
578 Wdeprecated-declarations
579 Common Var(warn_deprecated_decl) Init(1) Warning
580 Warn about uses of __attribute__((deprecated)) declarations.
582 Wdisabled-optimization
583 Common Var(warn_disabled_optimization) Warning
584 Warn when an optimization pass is disabled.
587 Common Var(warnings_are_errors)
588 Treat all warnings as errors.
592 Treat specified warning as error.
595 Common Var(extra_warnings) Warning
596 Print extra (possibly unwanted) warnings.
599 Common Var(flag_fatal_errors)
600 Exit on the first error occurred.
603 Common RejectNegative Joined Host_Wide_Int ByteSize Warning Var(warn_frame_larger_than_size) Init(HOST_WIDE_INT_MAX)
604 -Wframe-larger-than=<byte-size> Warn if a function's stack frame requires in excess of <byte-size>.
607 Common Var(warn_free_nonheap_object) Init(1) Warning
608 Warn when attempting to free a non-heap object.
611 Common Var(warn_hsa) Init(1) Warning
612 Warn when a function cannot be expanded to HSAIL.
614 Wimplicit-fallthrough
615 Common Alias(Wimplicit-fallthrough=,3,0) Warning
617 Wimplicit-fallthrough=
618 Common Var(warn_implicit_fallthrough) RejectNegative Joined UInteger Warning IntegerRange(0, 5)
619 Warn when a switch case falls through.
622 Common Var(warn_inline) Warning
623 Warn when an inlined function cannot be inlined.
625 Winvalid-memory-model
626 Common Var(warn_invalid_memory_model) Init(1) Warning
627 Warn when an atomic memory model parameter is known to be outside the valid range.
630 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
633 Common RejectNegative Joined Host_Wide_Int ByteSize Warning Var(warn_larger_than_size) Init(HOST_WIDE_INT_MAX)
634 -Wlarger-than=<byte-size> Warn if an object's size exceeds <byte-size>.
637 Var(warn_nonnull_compare) Warning
638 Warn if comparing pointer parameter with nonnull attribute with NULL.
641 Common Var(warn_null_dereference) Warning
642 Warn if dereferencing a NULL pointer may lead to erroneous or undefined behavior.
644 Wunsafe-loop-optimizations
645 Common Ignore Warning
646 Does nothing. Preserved for backward compatibility.
649 Common Warning Alias(Wsuggest-attribute=noreturn)
652 Common Var(warn_odr_violations) Init(1) Warning
653 Warn about some C++ One Definition Rule violations during link time optimization.
656 Common Var(warn_overflow) Init(1) Warning
657 Warn about overflow in arithmetic expressions.
660 Common Var(warn_lto_type_mismatch) Init(1) Warning
661 During link time optimization warn about mismatched types of global declarations.
664 Common Var(warn_packed) Warning
665 Warn when the packed attribute has no effect on struct layout.
668 Common Var(warn_padded) Warning
669 Warn when padding is required to align structure members.
672 Common Var(pedantic) Init(0) Warning
673 Issue warnings needed for strict compliance to the standard.
676 Common Var(warn_return_local_addr) Init(1) Warning
677 Warn about returning a pointer/reference to a local or temporary variable.
680 Common Var(warn_shadow) Warning
681 Warn when one variable shadows another. Same as -Wshadow=global.
684 Common Warning Alias(Wshadow)
685 Warn when one variable shadows another (globally).
688 Common Var(warn_shadow_local) Warning EnabledBy(Wshadow)
689 Warn when one local variable shadows another local variable or parameter.
692 Common Warning Undocumented Alias(Wshadow=local)
694 Wshadow=compatible-local
695 Common Var(warn_shadow_compatible_local) Warning EnabledBy(Wshadow=local)
696 Warn when one local variable shadows another local variable or parameter of compatible type.
698 Wshadow-compatible-local
699 Common Warning Undocumented Alias(Wshadow=compatible-local)
702 Common Var(warn_stack_protect) Warning
703 Warn when not issuing stack smashing protection for some reason.
706 Common Joined RejectNegative Host_Wide_Int ByteSize Var(warn_stack_usage) Warning Init(HOST_WIDE_INT_MAX)
707 -Wstack-usage=<byte-size> Warn if stack usage might exceed <byte-size>.
711 Warn about code which might break strict aliasing rules.
714 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
715 Warn about code which might break strict aliasing rules.
719 Warn about optimizations that assume that signed overflow is undefined.
722 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
723 Warn about optimizations that assume that signed overflow is undefined.
725 Wsuggest-attribute=cold
726 Common Var(warn_suggest_attribute_cold) Warning
727 Warn about functions which might be candidates for __attribute__((cold)).
729 Wsuggest-attribute=const
730 Common Var(warn_suggest_attribute_const) Warning
731 Warn about functions which might be candidates for __attribute__((const)).
733 Wsuggest-attribute=pure
734 Common Var(warn_suggest_attribute_pure) Warning
735 Warn about functions which might be candidates for __attribute__((pure)).
737 Wsuggest-attribute=noreturn
738 Common Var(warn_suggest_attribute_noreturn) Warning
739 Warn about functions which might be candidates for __attribute__((noreturn)).
741 Wsuggest-attribute=malloc
742 Common Var(warn_suggest_attribute_malloc) Warning
743 Warn about functions which might be candidates for __attribute__((malloc)).
746 Common Var(warn_suggest_final_types) Warning
747 Warn about C++ polymorphic types where adding final keyword would improve code quality.
749 Wsuggest-final-methods
750 Common Var(warn_suggest_final_methods) Warning
751 Warn about C++ virtual methods where adding final keyword would improve code quality.
754 Common Var(warn_switch_unreachable) Warning Init(1)
755 Warn about statements between switch's controlling expression and the first
759 Common Var(warn_system_headers) Warning
760 Do not suppress warnings from system headers.
763 Common Var(warn_trampolines) Warning
764 Warn whenever a trampoline is generated.
767 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
768 Warn if a comparison is always true or always false due to the limited range of the data type.
771 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
772 Warn about uninitialized automatic variables.
775 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
776 Warn about maybe uninitialized automatic variables.
779 Common Ignore Warning
780 Does nothing. Preserved for backward compatibility.
783 Common Var(warn_unused) Init(0) Warning
784 Enable all -Wunused- warnings.
786 Wunused-but-set-parameter
787 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
788 Warn when a function parameter is only set, otherwise unused.
790 Wunused-but-set-variable
791 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
792 Warn when a variable is only set, otherwise unused.
795 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
796 Warn when a function is unused.
799 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
800 Warn when a label is unused.
803 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
804 Warn when a function parameter is unused.
807 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
808 Warn when an expression value is unused.
811 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
812 Warn when a variable is unused.
815 Common Var(warn_coverage_mismatch) Init(1) Warning
816 Warn in case profiles in -fprofile-use do not match.
819 Common Var(warn_missing_profile) Init(1) Warning
820 Warn in case profiles in -fprofile-use do not exist.
822 Wvector-operation-performance
823 Common Var(warn_vector_operation_performance) Warning
824 Warn when a vector operation is compiled outside the SIMD.
839 Common Separate Var(aux_info_file_name)
840 -aux-info <file> Emit declaration information into <file>.
843 Common Joined Alias(aux-info)
846 Common Separate RejectDriver Var(aux_base_name)
849 Common Separate RejectDriver
859 -d<letters> Enable dumps from specific passes of the compiler.
862 Common Separate Var(dump_base_name)
863 -dumpbase <file> Set the file basename to be used for dumps.
866 Common Separate Var(dump_dir_name)
867 -dumpdir <dir> Set the directory name to be used for dumps.
882 Driver Joined Separate
884 ; This option has historically been passed down to the linker by an
885 ; accident of a %{e*} spec, so ensure it continues to be passed down
886 ; as a single option. The supported option for this purpose is
887 ; -rdynamic. See PR 47390.
891 ; The version of the C++ ABI in use. The following values are allowed:
893 ; 0: The version of the ABI believed most conformant with the C++ ABI
894 ; specification. This ABI may change as bugs are discovered and fixed.
895 ; Therefore, 0 will not necessarily indicate the same ABI in different
898 ; 1: The version of the ABI first used in G++ 3.2. No longer selectable.
900 ; 2: The version of the ABI first used in G++ 3.4, and the default
903 ; 3: The version of the ABI that fixes the missing underscore
904 ; in template non-type arguments of pointer type.
906 ; 4: The version of the ABI that introduces unambiguous mangling of
907 ; vector types. First selectable in G++ 4.5.
909 ; 5: The version of the ABI that ignores attribute const/noreturn
910 ; in function pointer mangling, and corrects mangling of decltype and
911 ; function parameters used in other parameters and the return type.
912 ; First selectable in G++ 4.6.
914 ; 6: The version of the ABI that doesn't promote scoped enums to int and
915 ; changes the mangling of template argument packs, const/static_cast,
916 ; prefix ++ and --, and a class scope function used as a template
918 ; First selectable in G++ 4.7.
920 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
921 ; corrects the mangling of lambdas in default argument scope.
922 ; First selectable in G++ 4.8.
924 ; 8: The version of the ABI that corrects the substitution behavior of
925 ; function types with function-cv-qualifiers.
926 ; First selectable in G++ 4.9 and default in G++ 5.
928 ; 9: The version of the ABI that corrects the alignment of nullptr_t.
929 ; First selectable and default in G++ 5.2.
931 ; 10: The version of the ABI that mangles attributes that affect type
932 ; identity, such as ia32 calling convention attributes (stdcall, etc.)
933 ; Default in G++ 6 (set in c_common_post_options).
935 ; 11: The version of the ABI that corrects mangling of sizeof... expressions
936 ; and introduces new inheriting constructor handling.
939 ; 12: Corrects the calling convention for classes with only deleted copy/move
940 ; constructors and changes passing/returning of empty records.
941 ; Default in G++ 8.1.
943 ; 13: Fixes the accidental change in 12 to the calling convention for classes
944 ; with deleted copy constructor and trivial move constructor.
945 ; Default in G++ 8.2.
947 ; Additional positive integers will be assigned as new versions of
948 ; the ABI become the default version of the ABI.
950 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0)
951 The version of the C++ ABI in use.
953 faggressive-loop-optimizations
954 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
955 Aggressively optimize loops using language constraints.
958 Common Report Var(flag_align_functions) Optimization
959 Align the start of functions.
962 Common RejectNegative Joined Var(str_align_functions) Optimization
964 flimit-function-alignment
965 Common Report Var(flag_limit_function_alignment) Optimization Init(0)
968 Common Report Var(flag_align_jumps) Optimization
969 Align labels which are only reached by jumping.
972 Common RejectNegative Joined Var(str_align_jumps) Optimization
975 Common Report Var(flag_align_labels) Optimization
979 Common RejectNegative Joined Var(str_align_labels) Optimization
982 Common Report Var(flag_align_loops) Optimization
983 Align the start of loops.
986 Common RejectNegative Joined Var(str_align_loops) Optimization
990 Does nothing. Preserved for backward compatibility.
994 Does nothing. Preserved for backward compatibility.
996 fargument-noalias-global
998 Does nothing. Preserved for backward compatibility.
1000 fargument-noalias-anything
1002 Does nothing. Preserved for backward compatibility.
1005 Common Driver Report Joined
1006 Select what to sanitize.
1009 Common Report Joined
1010 Select type of coverage sanitization.
1012 fasan-shadow-offset=
1013 Common Joined RejectNegative Var(common_deferred_options) Defer
1014 -fasan-shadow-offset=<number> Use custom shadow memory offset.
1017 Common Joined RejectNegative Var(common_deferred_options) Defer
1018 -fsanitize-sections=<sec1,sec2,...> Sanitize global variables
1019 in user-defined sections.
1022 Common Report Joined
1023 After diagnosing undefined behavior attempt to continue execution.
1027 This switch is deprecated; use -fsanitize-recover= instead.
1029 fsanitize-address-use-after-scope
1030 Common Driver Report Var(flag_sanitize_address_use_after_scope) Init(0)
1032 fsanitize-undefined-trap-on-error
1033 Common Driver Report Var(flag_sanitize_undefined_trap_on_error) Init(0)
1034 Use trap instead of a library function for undefined behavior sanitization.
1036 fasynchronous-unwind-tables
1037 Common Report Var(flag_asynchronous_unwind_tables) Optimization
1038 Generate unwind tables that are exact at each instruction boundary.
1041 Common Report Var(flag_auto_inc_dec) Init(1) Optimization
1042 Generate auto-inc/dec instructions.
1045 Common Report Var(flag_auto_profile)
1046 Use sample profile information for call graph node weights. The default
1047 profile file is fbdata.afdo in 'pwd'.
1050 Common Joined RejectNegative Var(auto_profile_file)
1051 Use sample profile information for call graph node weights. The profile
1052 file is specified in the argument.
1054 ; -fcheck-bounds causes gcc to generate array bounds checks.
1055 ; For C, C++ and ObjC: defaults off.
1056 ; For Java: defaults to on.
1057 ; For Fortran: defaults to off.
1059 Common Report Var(flag_bounds_check)
1060 Generate code to check bounds before indexing arrays.
1063 Common Report Var(flag_branch_on_count_reg) Optimization
1064 Replace add, compare, branch with branch on count register.
1066 fbranch-probabilities
1067 Common Report Var(flag_branch_probabilities) Optimization
1068 Use profiling information for branch probabilities.
1070 fbranch-target-load-optimize
1071 Common Report Var(flag_branch_target_load_optimize) Optimization
1072 Perform branch target load optimization before prologue / epilogue threading.
1074 fbranch-target-load-optimize2
1075 Common Report Var(flag_branch_target_load_optimize2) Optimization
1076 Perform branch target load optimization after prologue / epilogue threading.
1079 Common Report Var(flag_btr_bb_exclusive) Optimization
1080 Restrict target load migration not to re-use registers in any basic block.
1083 Common Joined RejectNegative Var(common_deferred_options) Defer
1084 -fcall-saved-<register> Mark <register> as being preserved across functions.
1087 Common Joined RejectNegative Var(common_deferred_options) Defer
1088 -fcall-used-<register> Mark <register> as being corrupted by function calls.
1090 ; Nonzero for -fcaller-saves: allocate values in regs that need to
1091 ; be saved across function calls, if that produces overall better code.
1092 ; Optional now, so people can test it.
1094 Common Report Var(flag_caller_saves) Optimization
1095 Save registers around function calls.
1099 This switch is deprecated; do not use.
1102 Common Var(flag_check_new)
1103 Check the return value of new in C++.
1106 Common Var(flag_checking) Init(CHECKING_P ? ENABLE_EXTRA_CHECKING ? 2 : 1 : 0)
1107 Perform internal consistency checkings.
1110 Common Joined RejectNegative UInteger Var(flag_checking)
1111 Perform internal consistency checkings.
1114 Common Report Var(flag_code_hoisting) Optimization
1115 Enable code hoisting.
1117 fcombine-stack-adjustments
1118 Common Report Var(flag_combine_stack_adjustments) Optimization
1119 Looks for opportunities to reduce stack adjustments and stack references.
1122 Common Report Var(flag_no_common,0)
1123 Do not put uninitialized globals in the common section.
1127 ; Converted by the driver to -fcompare-debug= options.
1130 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
1131 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump.
1133 fcompare-debug-second
1134 Common Driver RejectNegative Var(flag_compare_debug)
1135 Run only the second compilation of -fcompare-debug.
1138 Common Report Var(flag_compare_elim_after_reload) Optimization
1139 Perform comparison elimination after register allocation has finished.
1142 Common Var(flag_conserve_stack) Optimization
1143 Do not perform optimizations increasing noticeably stack usage.
1146 Common Report Var(flag_cprop_registers) Optimization
1147 Perform a register copy-propagation optimization pass.
1150 Common Report Var(flag_crossjumping) Optimization
1151 Perform cross-jumping optimization.
1154 Common Report Var(flag_cse_follow_jumps) Optimization
1155 When running CSE, follow jumps to their targets.
1159 Does nothing. Preserved for backward compatibility.
1162 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
1163 Omit range reduction step when performing complex division.
1166 Common Report Var(flag_cx_fortran_rules) Optimization
1167 Complex multiplication and division follow Fortran rules.
1170 Common Report Var(flag_data_sections)
1171 Place data items into their own section.
1174 Common Report Var(common_deferred_options) Defer
1175 List all available debugging counters with their limits and counts.
1178 Common RejectNegative Joined Var(common_deferred_options) Defer
1179 -fdbg-cnt=<counter>[:<lower_limit>]:<upper_limit>[,<counter>:...] Set the debug counter limit.
1182 Common Joined RejectNegative Var(common_deferred_options) Defer
1183 -fdebug-prefix-map=<old>=<new> Map one directory name to another in debug information.
1186 Common Joined RejectNegative Var(common_deferred_options) Defer
1187 -ffile-prefix-map=<old>=<new> Map one directory name to another in compilation result.
1189 fdebug-types-section
1190 Common Report Var(flag_debug_types_section) Init(0)
1191 Output .debug_types section when using DWARF v4 debuginfo.
1193 ; Nonzero for -fdefer-pop: don't pop args after each function call
1194 ; instead save them up to pop many calls' args with one insns.
1196 Common Report Var(flag_defer_pop) Optimization
1197 Defer popping functions args from stack until later.
1200 Common Report Var(flag_delayed_branch) Optimization
1201 Attempt to fill delay slots of branch instructions.
1203 fdelete-dead-exceptions
1204 Common Report Var(flag_delete_dead_exceptions) Init(0) Optimization
1205 Delete dead instructions that may throw exceptions.
1207 fdelete-null-pointer-checks
1208 Common Report Var(flag_delete_null_pointer_checks) Init(-1) Optimization
1209 Delete useless null pointer checks.
1211 fdevirtualize-at-ltrans
1212 Common Report Var(flag_ltrans_devirtualize)
1213 Stream extra data to support more aggressive devirtualization in LTO local transformation mode.
1215 fdevirtualize-speculatively
1216 Common Report Var(flag_devirtualize_speculatively) Optimization
1217 Perform speculative devirtualization.
1220 Common Report Var(flag_devirtualize) Optimization
1221 Try to convert virtual calls to direct ones.
1223 fdiagnostics-show-location=
1224 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1225 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics.
1227 ; Required for these enum values.
1232 Name(diagnostic_prefixing_rule) Type(int)
1235 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1238 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1240 fdiagnostics-show-caret
1241 Common Var(flag_diagnostics_show_caret) Init(1)
1242 Show the source line with a caret indicating the column.
1244 fdiagnostics-show-labels
1245 Common Var(flag_diagnostics_show_labels) Init(1)
1246 Show labels annotating ranges of source code when showing source
1248 fdiagnostics-show-line-numbers
1249 Common Var(flag_diagnostics_show_line_numbers) Init(1)
1250 Show line numbers in the left margin when showing source
1253 Common Alias(fdiagnostics-color=,always,never)
1257 Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1258 -fdiagnostics-color=[never|always|auto] Colorize diagnostics.
1260 ; Required for these enum values.
1265 Name(diagnostic_color_rule) Type(int)
1268 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1271 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1274 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1276 fdiagnostics-parseable-fixits
1277 Common Var(flag_diagnostics_parseable_fixits)
1278 Print fix-it hints in machine-readable form.
1280 fdiagnostics-generate-patch
1281 Common Var(flag_diagnostics_generate_patch)
1282 Print fix-it hints to stderr in unified diff format.
1284 fdiagnostics-show-option
1285 Common Var(flag_diagnostics_show_option) Init(1)
1286 Amend appropriate diagnostic messages with the command line option that controls them.
1288 fdiagnostics-minimum-margin-width=
1289 Common Joined UInteger Var(diagnostics_minimum_margin_width) Init(6)
1290 Set minimum width of left margin of source code when showing source
1293 Common Joined RejectNegative Var(common_deferred_options) Defer
1294 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass.
1297 Common Joined RejectNegative Var(common_deferred_options) Defer
1298 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass.
1301 Common Joined RejectNegative Var(common_deferred_options) Defer
1302 -fdump-<type> Dump various compiler internals to a file.
1305 Driver RejectNegative
1308 Common RejectNegative Joined Var(flag_dump_final_insns)
1309 -fdump-final-insns=filename Dump to filename the insns at the end of translation.
1312 Common RejectNegative Joined Var(flag_dump_go_spec)
1313 -fdump-go-spec=filename Write all declarations to file as Go code.
1316 Common Report Var(flag_dump_noaddr)
1317 Suppress output of addresses in debugging dumps.
1320 Common Driver Var(flag_report_bug)
1321 Collect and dump debug information into temporary file if ICE in C/C++
1324 fdump-internal-locations
1325 Common Var(flag_dump_locations) Init(0)
1326 Dump detailed information on GCC's internal representation of source code locations.
1329 Common Var(flag_dump_passes) Init(0)
1330 Dump optimization passes.
1333 Common Report Var(flag_dump_unnumbered)
1334 Suppress output of instruction numbers, line number notes and addresses in debugging dumps.
1336 fdump-unnumbered-links
1337 Common Report Var(flag_dump_unnumbered_links)
1338 Suppress output of previous and next insn numbers in debugging dumps.
1341 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1342 Enable CFI tables via GAS assembler directives.
1345 Common Report Var(flag_early_inlining) Init(1) Optimization
1346 Perform early inlining.
1348 feliminate-dwarf2-dups
1350 Does nothing. Preserved for backward compatibility.
1353 Common Report Var(flag_ipa_sra) Init(0) Optimization
1354 Perform interprocedural reduction of aggregates.
1356 feliminate-unused-debug-symbols
1357 Common Report Var(flag_debug_only_used_symbols)
1358 Perform unused symbol elimination in debug info.
1360 feliminate-unused-debug-types
1361 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1362 Perform unused type elimination in debug info.
1364 femit-class-debug-always
1365 Common Report Var(flag_emit_class_debug_always) Init(0)
1366 Do not suppress C++ class debug information.
1369 Common Report Var(flag_exceptions) Optimization
1370 Enable exception handling.
1372 fexpensive-optimizations
1373 Common Report Var(flag_expensive_optimizations) Optimization
1374 Perform a number of minor, expensive optimizations.
1377 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT) SetByCombined
1378 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision.
1381 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1384 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1387 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1389 ; Whether we permit the extended set of values for FLT_EVAL_METHOD
1390 ; introduced in ISO/IEC TS 18661-3, or limit ourselves to those in C99/C11.
1391 fpermitted-flt-eval-methods=
1392 Common Joined RejectNegative Enum(permitted_flt_eval_methods) Var(flag_permitted_flt_eval_methods) Init(PERMITTED_FLT_EVAL_METHODS_DEFAULT)
1393 -fpermitted-flt-eval-methods=[c11|ts-18661] Specify which values of FLT_EVAL_METHOD are permitted.
1396 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)
1399 Enum(permitted_flt_eval_methods) String(c11) Value(PERMITTED_FLT_EVAL_METHODS_C11)
1402 Enum(permitted_flt_eval_methods) String(ts-18661-3) Value(PERMITTED_FLT_EVAL_METHODS_TS_18661)
1408 Common Var(flag_fat_lto_objects)
1409 Output lto objects containing both the intermediate language and binary output.
1412 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1413 Assume no NaNs or infinities are generated.
1416 Common Joined RejectNegative Var(common_deferred_options) Defer
1417 -ffixed-<register> Mark <register> as being unavailable to the compiler.
1420 Common Report Var(flag_float_store) Optimization
1421 Don't allocate floats and doubles in extended-precision registers.
1425 Does nothing. Preserved for backward compatibility.
1428 Common Report Var(flag_forward_propagate) Optimization
1429 Perform a forward propagation pass on RTL.
1432 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization
1433 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1436 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1439 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1441 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1443 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1446 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1448 ffp-int-builtin-inexact
1449 Common Report Var(flag_fp_int_builtin_inexact) Init(1) Optimization
1450 Allow built-in functions ceil, floor, round, trunc to raise \"inexact\" exceptions.
1452 ; Nonzero means don't put addresses of constant functions in registers.
1453 ; Used for compiling the Unix kernel, where strange substitutions are
1454 ; done on the assembly output.
1456 Common Report Var(flag_no_function_cse,0) Optimization
1457 Allow function addresses to be held in registers.
1460 Common Report Var(flag_function_sections)
1461 Place each function into its own section.
1464 Common Report Var(flag_gcse) Optimization
1465 Perform global common subexpression elimination.
1468 Common Report Var(flag_gcse_lm) Init(1) Optimization
1469 Perform enhanced load motion during global common subexpression elimination.
1472 Common Report Var(flag_gcse_sm) Init(0) Optimization
1473 Perform store motion after global common subexpression elimination.
1476 Common Report Var(flag_gcse_las) Init(0) Optimization
1477 Perform redundant load after store elimination in global common subexpression
1481 Common Report Var(flag_gcse_after_reload) Optimization
1482 Perform global common subexpression elimination after register allocation has
1486 Name(dwarf_gnat_encodings) Type(int)
1489 Enum(dwarf_gnat_encodings) String(all) Value(DWARF_GNAT_ENCODINGS_ALL)
1492 Enum(dwarf_gnat_encodings) String(gdb) Value(DWARF_GNAT_ENCODINGS_GDB)
1495 Enum(dwarf_gnat_encodings) String(minimal) Value(DWARF_GNAT_ENCODINGS_MINIMAL)
1498 Common Enum(dwarf_gnat_encodings) Joined RejectNegative Report Undocumented Var(gnat_encodings)
1499 -fgnat-encodings=[all|gdb|minimal] Select the balance between GNAT encodings and standard DWARF emitted in the debug information
1501 ; This option is not documented yet as its semantics will change.
1503 Common Report Var(flag_graphite) Optimization
1504 Enable in and out of Graphite representation.
1507 Common Report Var(flag_graphite_identity) Optimization
1508 Enable Graphite Identity transformation.
1510 fhoist-adjacent-loads
1511 Common Report Var(flag_hoist_adjacent_loads) Optimization
1512 Enable hoisting adjacent loads to encourage generating conditional move
1516 Common Undocumented Report Var(flag_keep_gc_roots_live) Optimization
1517 ; Always keep a pointer to a live memory block
1519 floop-parallelize-all
1520 Common Report Var(flag_loop_parallelize_all) Optimization
1521 Mark all loops as parallel.
1524 Common Alias(floop-nest-optimize)
1525 Enable loop nest transforms. Same as -floop-nest-optimize.
1528 Common Report Var(flag_loop_interchange) Optimization
1529 Enable loop interchange on trees.
1532 Common Alias(floop-nest-optimize)
1533 Enable loop nest transforms. Same as -floop-nest-optimize.
1535 floop-unroll-and-jam
1536 Common Report Var(flag_unroll_jam) Optimization
1537 Perform unroll-and-jam on loops.
1540 Common Report Var(flag_tm)
1541 Enable support for GNU transactional memory.
1544 Common Report Var(flag_gnu_unique) Init(1)
1545 Use STB_GNU_UNIQUE if supported by the assembler.
1549 Does nothing. Preserved for backward compatibility.
1552 Common Report Var(flag_loop_nest_optimize) Optimization
1553 Enable the loop nest optimizer.
1555 fstrict-volatile-bitfields
1556 Common Report Var(flag_strict_volatile_bitfields) Init(-1) Optimization
1557 Force bitfield accesses to match their type width.
1560 Common Report Var(flag_store_merging) Optimization
1561 Merge adjacent stores.
1563 fguess-branch-probability
1564 Common Report Var(flag_guess_branch_prob) Optimization
1565 Enable guessing of branch probabilities.
1567 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1568 ; Generate position-independent code for executables if possible
1569 ; On SVR4 targets, it also controls whether or not to emit a
1570 ; string identifying the compiler.
1572 Common Report Var(flag_no_ident,0)
1573 Process #ident directives.
1576 Common Report Var(flag_if_conversion) Optimization
1577 Perform conversion of conditional jumps to branchless equivalents.
1580 Common Report Var(flag_if_conversion2) Optimization
1581 Perform conversion of conditional jumps to conditional execution.
1584 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization
1585 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1588 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1591 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1594 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1597 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1599 ftree-loop-if-convert
1600 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1601 Convert conditional jumps in innermost loops to branchless equivalents.
1603 ftree-loop-if-convert-stores
1605 Does nothing. Preserved for backward compatibility.
1607 ; -finhibit-size-directive inhibits output of .size for ELF.
1608 ; This is used only for compiling crtstuff.c,
1609 ; and it may be extended to other effects
1610 ; needed for crtstuff.c on other systems.
1611 finhibit-size-directive
1612 Common Report Var(flag_inhibit_size_directive)
1613 Do not generate .size directives.
1616 Common Report Var(flag_indirect_inlining) Optimization
1617 Perform indirect inlining.
1619 ; General flag to enable inlining. Specifying -fno-inline will disable
1620 ; all inlining apart from always-inline functions.
1622 Common Report Var(flag_no_inline,0) Init(0) Optimization
1623 Enable inlining of function declared \"inline\", disabling disables all inlining.
1625 finline-small-functions
1626 Common Report Var(flag_inline_small_functions) Optimization
1627 Integrate functions into their callers when code size is known not to grow.
1630 Common Report Var(flag_inline_functions) Optimization
1631 Integrate functions not declared \"inline\" into their callers when profitable.
1633 finline-functions-called-once
1634 Common Report Var(flag_inline_functions_called_once) Optimization
1635 Integrate functions only required by their single caller.
1638 Common RejectNegative Joined Alias(finline-limit=)
1641 Common RejectNegative Joined UInteger
1642 -finline-limit=<number> Limit the size of inlined functions to <number>.
1645 Common Report Var(flag_inline_atomics) Init(1) Optimization
1646 Inline __atomic operations when a lock free instruction sequence is available.
1649 Common RejectNegative Alias(fcf-protection=,full)
1652 Common Report Joined RejectNegative Enum(cf_protection_level) Var(flag_cf_protection) Init(CF_NONE)
1653 -fcf-protection=[full|branch|return|none] Instrument functions with checks to verify jump/call/return control-flow transfer
1654 instructions have valid targets.
1657 Name(cf_protection_level) Type(enum cf_protection_level) UnknownError(unknown Control-Flow Protection Level %qs)
1660 Enum(cf_protection_level) String(full) Value(CF_FULL)
1663 Enum(cf_protection_level) String(branch) Value(CF_BRANCH)
1666 Enum(cf_protection_level) String(return) Value(CF_RETURN)
1669 Enum(cf_protection_level) String(none) Value(CF_NONE)
1671 finstrument-functions
1672 Common Report Var(flag_instrument_function_entry_exit)
1673 Instrument function entry and exit with profiling calls.
1675 finstrument-functions-exclude-function-list=
1676 Common RejectNegative Joined
1677 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions.
1679 finstrument-functions-exclude-file-list=
1680 Common RejectNegative Joined
1681 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files.
1684 Common Report Var(flag_ipa_cp) Optimization
1685 Perform interprocedural constant propagation.
1688 Common Report Var(flag_ipa_cp_clone) Optimization
1689 Perform cloning to make Interprocedural constant propagation stronger.
1693 Does nothing. Preserved for backward compatibility.
1696 Common Report Var(flag_ipa_bit_cp) Optimization
1697 Perform interprocedural bitwise constant propagation.
1700 Common Report Var(flag_ipa_profile) Init(0) Optimization
1701 Perform interprocedural profile propagation.
1704 Common Report Var(flag_ipa_pta) Init(0) Optimization
1705 Perform interprocedural points-to analysis.
1708 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1709 Discover pure and const functions.
1712 Common Report Var(flag_ipa_icf) Optimization
1713 Perform Identical Code Folding for functions and read-only variables.
1716 Common Report Var(flag_ipa_icf_functions) Optimization
1717 Perform Identical Code Folding for functions.
1720 Common Report Var(flag_ipa_icf_variables) Optimization
1721 Perform Identical Code Folding for variables.
1724 Common Report Var(flag_ipa_reference) Init(0) Optimization
1725 Discover readonly and non addressable static variables.
1729 Does nothing. Preserved for backward compatibility.
1733 Does nothing. Preserved for backward compatibility.
1736 Common Report Var(flag_ipa_vrp) Optimization
1737 Perform IPA Value Range Propagation.
1740 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization
1741 -fira-algorithm=[CB|priority] Set the used IRA algorithm.
1744 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1747 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1750 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1753 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT) Optimization
1754 -fira-region=[one|all|mixed] Set regions for IRA.
1757 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1760 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1763 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1766 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1769 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1770 Use IRA based register pressure calculation
1771 in RTL hoist optimizations.
1774 Common Report Var(flag_ira_loop_pressure) Optimization
1775 Use IRA based register pressure calculation
1776 in RTL loop optimizations.
1778 fira-share-save-slots
1779 Common Report Var(flag_ira_share_save_slots) Init(1) Optimization
1780 Share slots for saving different hard registers.
1782 fira-share-spill-slots
1783 Common Report Var(flag_ira_share_spill_slots) Init(1) Optimization
1784 Share stack slots for spilled pseudo-registers.
1787 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1788 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1791 Common Report Var(flag_ivopts) Init(1) Optimization
1792 Optimize induction variables on trees.
1795 Common Var(flag_jump_tables) Init(1) Optimization
1796 Use jump tables for sufficiently large switch statements.
1798 fkeep-inline-functions
1799 Common Report Var(flag_keep_inline_functions)
1800 Generate code for functions even if they are fully inlined.
1802 fkeep-static-functions
1803 Common Report Var(flag_keep_static_functions)
1804 Generate code for static functions even if they are never called.
1807 Common Report Var(flag_keep_static_consts) Init(1)
1808 Emit static const variables even if they are not used.
1811 Common Report Var(flag_leading_underscore) Init(-1)
1812 Give external symbols a leading underscore.
1816 Does nothing. Preserved for backward compatibility.
1819 Common Report Var(flag_lra_remat) Optimization
1820 Do CFG-sensitive rematerialization in LRA.
1824 Enable link-time optimization.
1827 Common RejectNegative Joined Var(flag_lto)
1828 Link-time optimization with number of parallel jobs or jobserver.
1831 Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
1834 Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
1837 Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
1840 Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
1843 Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
1846 Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
1849 Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)
1850 Specify the algorithm to partition symbols and vars at linktime.
1852 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1853 flto-compression-level=
1854 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1) IntegerRange(0, 9)
1855 -flto-compression-level=<number> Use zlib compression level <number> for IL.
1857 flto-odr-type-merging
1858 Common Report Var(flag_lto_odr_type_mering) Init(1)
1859 Merge C++ types using One Definition Rule.
1862 Common Report Var(flag_lto_report) Init(0)
1863 Report various link-time optimization statistics.
1866 Common Report Var(flag_lto_report_wpa) Init(0)
1867 Report various link-time optimization statistics for WPA only.
1870 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1871 Set errno after built-in math functions.
1874 Common Joined RejectNegative UInteger Var(flag_max_errors)
1875 -fmax-errors=<number> Maximum number of errors to report.
1878 Common Report Var(mem_report)
1879 Report on permanent memory allocation.
1882 Common Report Var(mem_report_wpa)
1883 Report on permanent memory allocation in WPA only.
1885 ; This will attempt to merge constant section constants, if 1 only
1886 ; string constants and constants from constant pool, if 2 also constant
1888 fmerge-all-constants
1889 Common Report Var(flag_merge_constants,2) Init(1)
1890 Attempt to merge identical constants and constant variables.
1893 Common Report Var(flag_merge_constants,1)
1894 Attempt to merge identical constants across compilation units.
1896 fmerge-debug-strings
1897 Common Report Var(flag_merge_debug_strings) Init(1)
1898 Attempt to merge identical debug strings across compilation units.
1901 Common RejectNegative Joined UInteger
1902 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping.
1905 Common Report Var(flag_modulo_sched) Optimization
1906 Perform SMS based modulo scheduling before the first scheduling pass.
1908 fmodulo-sched-allow-regmoves
1909 Common Report Var(flag_modulo_sched_allow_regmoves) Optimization
1910 Perform SMS based modulo scheduling with register moves allowed.
1912 fmove-loop-invariants
1913 Common Report Var(flag_move_loop_invariants) Optimization
1914 Move loop invariant computations out of loops.
1917 Common Var(flag_dce) Init(1) Optimization
1918 Use the RTL dead code elimination pass.
1921 Common Var(flag_dse) Init(1) Optimization
1922 Use the RTL dead store elimination pass.
1924 freschedule-modulo-scheduled-loops
1925 Common Report Var(flag_resched_modulo_sched) Optimization
1926 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling.
1928 fnon-call-exceptions
1929 Common Report Var(flag_non_call_exceptions) Optimization
1930 Support synchronous non-call exceptions.
1933 Common Driver Joined MissingArgError(options or targets missing after %qs)
1934 -foffload=<targets>=<options> Specify offloading targets and options for them.
1937 Common Joined RejectNegative Enum(offload_abi) Var(flag_offload_abi) Init(OFFLOAD_ABI_UNSET)
1938 -foffload-abi=[lp64|ilp32] Set the ABI to use in an offload compiler.
1941 Name(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs)
1944 Enum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32)
1947 Enum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64)
1950 Common Report Var(flag_omit_frame_pointer) Optimization
1951 When possible do not generate stack frames.
1954 Common Report Var(flag_opt_info) Optimization
1955 Enable all optimization info dumps on stderr.
1958 Common Joined RejectNegative Var(common_deferred_options) Defer
1959 -fopt-info[-<type>=filename] Dump compiler optimization details.
1961 fsave-optimization-record
1962 Common Report Var(flag_save_optimization_record) Optimization
1963 Write a SRCFILE.opt-record.json file detailing what optimizations were performed.
1965 foptimize-register-move
1967 Does nothing. Preserved for backward compatibility.
1969 foptimize-sibling-calls
1970 Common Report Var(flag_optimize_sibling_calls) Optimization
1971 Optimize sibling and tail recursive calls.
1974 Common Report Var(flag_partial_inlining) Optimization
1975 Perform partial inlining.
1978 Common Report Var(pre_ipa_mem_report)
1979 Report on memory allocation before interprocedural optimization.
1981 fpost-ipa-mem-report
1982 Common Report Var(post_ipa_mem_report)
1983 Report on memory allocation before interprocedural optimization.
1986 Common Report Var(flag_pack_struct) Optimization
1987 Pack structure members together without holes.
1990 Common RejectNegative Joined UInteger Optimization
1991 -fpack-struct=<number> Set initial maximum structure member alignment.
1994 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1995 Return small aggregates in memory, not registers.
1998 Common Report Var(flag_peel_loops) Optimization
1999 Perform loop peeling.
2002 Common Report Var(flag_no_peephole,0) Optimization
2003 Enable machine specific peephole optimizations.
2006 Common Report Var(flag_peephole2) Optimization
2007 Enable an RTL peephole pass before sched2.
2010 Common Report Var(flag_pic,2) Negative(fPIE) Init(-1)
2011 Generate position-independent code if possible (large mode).
2014 Common Report Var(flag_pie,2) Negative(fpic) Init(-1)
2015 Generate position-independent code for executables if possible (large mode).
2018 Common Report Var(flag_pic,1) Negative(fpie) Init(-1)
2019 Generate position-independent code if possible (small mode).
2022 Common Report Var(flag_pie,1) Negative(fPIC) Init(-1)
2023 Generate position-independent code for executables if possible (small mode).
2026 Common Report Var(flag_plt) Init(1) Optimization
2027 Use PLT for PIC calls (-fno-plt: load the address from GOT at call site).
2030 Common Joined RejectNegative Var(common_deferred_options) Defer
2031 Specify a plugin to load.
2034 Common Joined RejectNegative Var(common_deferred_options) Defer
2035 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>.
2037 fpredictive-commoning
2038 Common Report Var(flag_predictive_commoning) Optimization
2039 Run predictive commoning optimization.
2041 fprefetch-loop-arrays
2042 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
2043 Generate prefetch instructions, if available, for arrays in loops.
2046 Common Report Var(profile_flag)
2047 Enable basic program profiling code.
2050 Common Report Var(profile_abs_path_flag)
2051 Generate absolute source path names for gcov.
2054 Common Report Var(profile_arc_flag)
2055 Insert arc-based program profiling code.
2058 Common Joined RejectNegative Var(profile_data_prefix)
2059 Set the top-level directory for storing the profile data.
2060 The default is 'pwd'.
2063 Common Report Var(flag_profile_correction)
2064 Enable correction of flow inconsistent profile data input.
2067 Common Joined RejectNegative Enum(profile_update) Var(flag_profile_update) Init(PROFILE_UPDATE_SINGLE)
2068 -fprofile-update=[single|atomic|prefer-atomic] Set the profile update method.
2071 Name(profile_update) Type(enum profile_update) UnknownError(unknown profile update method %qs)
2074 Enum(profile_update) String(single) Value(PROFILE_UPDATE_SINGLE)
2077 Enum(profile_update) String(atomic) Value(PROFILE_UPDATE_ATOMIC)
2080 Enum(profile_update) String(prefer-atomic) Value(PROFILE_UPDATE_PREFER_ATOMIC)
2084 Enable common options for generating profile info for profile feedback directed optimizations.
2087 Common Joined RejectNegative
2088 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=.
2091 Common Var(flag_profile_use)
2092 Enable common options for performing profile feedback directed optimizations.
2095 Common Joined RejectNegative
2096 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=.
2099 Common Report Var(flag_profile_values)
2100 Insert code to profile values of expressions.
2103 Common Report Var(profile_report)
2104 Report on consistency of profile.
2106 fprofile-reorder-functions
2107 Common Report Var(flag_profile_reorder_functions)
2108 Enable function reordering that improves code placement.
2110 fpatchable-function-entry=
2111 Common Joined Optimization
2112 Insert NOP instructions at each function entry.
2115 Common Var(common_deferred_options) Defer
2118 Common Joined RejectNegative Var(common_deferred_options) Defer
2119 -frandom-seed=<string> Make compile reproducible using <string>.
2121 ; This switch causes the command line that was used to create an
2122 ; object file to be recorded into the object file. The exact format
2123 ; of this recording is target and binary file format dependent.
2124 ; It is related to the -fverbose-asm switch, but that switch only
2125 ; records information in the assembler output file as comments, so
2126 ; they never reach the object file.
2127 frecord-gcc-switches
2128 Common Report Var(flag_record_gcc_switches)
2129 Record gcc command line switches in the object file.
2132 Common Report Var(flag_pcc_struct_return,0) Optimization
2133 Return small aggregates in registers.
2137 Does nothing. Preserved for backward compatibility.
2140 Common Report Var(flag_lifetime_dse,2) Init(2) Optimization
2141 Tell DSE that the storage for a C++ object is dead when the constructor
2142 starts and when the destructor finishes.
2145 Common Joined RejectNegative UInteger Var(flag_lifetime_dse) Optimization IntegerRange(0, 2)
2147 flive-range-shrinkage
2148 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
2149 Relief of register pressure through live range shrinkage.
2152 Common Report Var(flag_rename_registers) Init(2) Optimization
2153 Perform a register renaming optimization pass.
2156 Common Report Var(flag_schedule_fusion) Init(2) Optimization
2157 Perform a target dependent instruction fusion optimization pass.
2160 Common Report Var(flag_reorder_blocks) Optimization
2161 Reorder basic blocks to improve code placement.
2163 freorder-blocks-algorithm=
2164 Common Joined RejectNegative Enum(reorder_blocks_algorithm) Var(flag_reorder_blocks_algorithm) Init(REORDER_BLOCKS_ALGORITHM_SIMPLE) Optimization
2165 -freorder-blocks-algorithm=[simple|stc] Set the used basic block reordering algorithm.
2168 Name(reorder_blocks_algorithm) Type(enum reorder_blocks_algorithm) UnknownError(unknown basic block reordering algorithm %qs)
2171 Enum(reorder_blocks_algorithm) String(simple) Value(REORDER_BLOCKS_ALGORITHM_SIMPLE)
2174 Enum(reorder_blocks_algorithm) String(stc) Value(REORDER_BLOCKS_ALGORITHM_STC)
2176 freorder-blocks-and-partition
2177 Common Report Var(flag_reorder_blocks_and_partition) Optimization
2178 Reorder basic blocks and partition into hot and cold sections.
2181 Common Report Var(flag_reorder_functions) Optimization
2182 Reorder functions to improve code placement.
2184 frerun-cse-after-loop
2185 Common Report Var(flag_rerun_cse_after_loop) Optimization
2186 Add a common subexpression elimination pass after loop optimizations.
2190 Does nothing. Preserved for backward compatibility.
2193 Common Report Var(flag_rounding_math) Optimization SetByCombined
2194 Disable optimizations that assume default FP rounding behavior.
2197 Common Report Var(flag_schedule_interblock) Init(1) Optimization
2198 Enable scheduling across basic blocks.
2201 Common Report Var(flag_sched_pressure) Init(0) Optimization
2202 Enable register pressure sensitive insn scheduling.
2205 Common Report Var(flag_schedule_speculative) Init(1) Optimization
2206 Allow speculative motion of non-loads.
2209 Common Report Var(flag_schedule_speculative_load) Optimization
2210 Allow speculative motion of some loads.
2212 fsched-spec-load-dangerous
2213 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
2214 Allow speculative motion of more loads.
2217 Common RejectNegative Joined UInteger Var(sched_verbose_param) Init(1)
2218 -fsched-verbose=<number> Set the verbosity level of the scheduler.
2220 fsched2-use-superblocks
2221 Common Report Var(flag_sched2_use_superblocks) Optimization
2222 If scheduling post reload, do superblock scheduling.
2226 Does nothing. Preserved for backward compatibility.
2229 Common Report Var(flag_schedule_insns) Optimization
2230 Reschedule instructions before register allocation.
2233 Common Report Var(flag_schedule_insns_after_reload) Optimization
2234 Reschedule instructions after register allocation.
2236 ; This flag should be on when a target implements non-trivial
2237 ; scheduling hooks, maybe saving some information for its own sake.
2238 ; On IA64, for example, this is used for correct bundling.
2239 fselective-scheduling
2240 Common Report Var(flag_selective_scheduling) Optimization
2241 Schedule instructions using selective scheduling algorithm.
2243 fselective-scheduling2
2244 Common Report Var(flag_selective_scheduling2) Optimization
2245 Run selective scheduling after reload.
2248 Common Undocumented Joined Var(flag_self_test)
2249 Run self-tests, using the given path to locate test files.
2251 fsel-sched-pipelining
2252 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
2253 Perform software pipelining of inner loops during selective scheduling.
2255 fsel-sched-pipelining-outer-loops
2256 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
2257 Perform software pipelining of outer loops during selective scheduling.
2259 fsel-sched-reschedule-pipelined
2260 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
2261 Reschedule pipelined regions without pipelining.
2263 fsemantic-interposition
2264 Common Report Var(flag_semantic_interposition) Init(1)
2265 Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker.
2267 ; sched_stalled_insns means that insns can be moved prematurely from the queue
2268 ; of stalled insns into the ready list.
2269 fsched-stalled-insns
2270 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
2271 Allow premature scheduling of queued insns.
2273 fsched-stalled-insns=
2274 Common RejectNegative Joined UInteger Optimization
2275 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled.
2277 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
2278 ; be examined for a dependency on a stalled insn that is candidate for
2279 ; premature removal from the queue of stalled insns into the ready list (has
2280 ; an effect only if the flag 'sched_stalled_insns' is set).
2281 fsched-stalled-insns-dep
2282 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
2283 Set dependence distance checking in premature scheduling of queued insns.
2285 fsched-stalled-insns-dep=
2286 Common RejectNegative Joined UInteger Optimization
2287 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns.
2289 fsched-group-heuristic
2290 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
2291 Enable the group heuristic in the scheduler.
2293 fsched-critical-path-heuristic
2294 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
2295 Enable the critical path heuristic in the scheduler.
2297 fsched-spec-insn-heuristic
2298 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
2299 Enable the speculative instruction heuristic in the scheduler.
2301 fsched-rank-heuristic
2302 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
2303 Enable the rank heuristic in the scheduler.
2305 fsched-last-insn-heuristic
2306 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
2307 Enable the last instruction heuristic in the scheduler.
2309 fsched-dep-count-heuristic
2310 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
2311 Enable the dependent count heuristic in the scheduler.
2314 Common Report Var(flag_section_anchors) Optimization
2315 Access data in the same section from shared anchor points.
2319 Does nothing. Preserved for backward compatibility.
2323 Does nothing. Preserved for backward compatibility.
2326 Common Report Var(flag_ree) Init(0)
2327 Turn on Redundant Extensions Elimination pass.
2330 Common Report Var(flag_show_column) Init(1)
2331 Show column numbers in diagnostics, when available. Default on.
2334 Common Report Var(flag_shrink_wrap) Optimization
2335 Emit function prologues only before parts of the function that need it,
2336 rather than at the top of the function.
2338 fshrink-wrap-separate
2339 Common Report Var(flag_shrink_wrap_separate) Init(1) Optimization
2340 Shrink-wrap parts of the prologue and epilogue separately.
2343 Common Report Var(flag_signaling_nans) Optimization SetByCombined
2344 Disable optimizations observable by IEEE signaling NaNs.
2347 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
2348 Disable floating point optimizations that ignore the IEEE signedness of zero.
2350 fsingle-precision-constant
2351 Common Report Var(flag_single_precision_constant) Optimization
2352 Convert floating point constants to single precision constants.
2354 fsplit-ivs-in-unroller
2355 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
2356 Split lifetimes of induction variables when loops are unrolled.
2359 Common Report Var(flag_split_stack) Init(-1)
2360 Generate discontiguous stack frames.
2363 Common Report Var(flag_split_wide_types) Optimization
2364 Split wide types into independent registers.
2367 Common Report Var(flag_ssa_backprop) Init(1) Optimization
2368 Enable backward propagation of use properties at the SSA level.
2371 Common Report Var(flag_ssa_phiopt) Optimization
2372 Optimize conditional patterns using SSA PHI nodes.
2375 Common Report Var(flag_stdarg_opt) Init(1) Optimization
2376 Optimize amount of stdarg registers saved to stack at start of function.
2378 fvariable-expansion-in-unroller
2379 Common Report Var(flag_variable_expansion_in_unroller) Optimization
2380 Apply variable expansion when loops are unrolled.
2383 Common Report RejectNegative Joined Optimization
2384 -fstack-check=[no|generic|specific] Insert stack checking code into the program.
2387 Common Alias(fstack-check=, specific, no)
2388 Insert stack checking code into the program. Same as -fstack-check=specific.
2390 fstack-clash-protection
2391 Common Report Var(flag_stack_clash_protection) Optimization
2392 Insert code to probe each page of stack space as it is allocated to protect
2393 from stack-clash style attacks.
2396 Common Var(common_deferred_options) Defer
2398 fstack-limit-register=
2399 Common RejectNegative Joined Var(common_deferred_options) Defer
2400 -fstack-limit-register=<register> Trap if the stack goes past <register>.
2402 fstack-limit-symbol=
2403 Common RejectNegative Joined Var(common_deferred_options) Defer
2404 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>.
2407 Common Report Var(flag_stack_protect, 1) Init(-1) Optimization
2408 Use propolice as a stack protection method.
2410 fstack-protector-all
2411 Common Report RejectNegative Var(flag_stack_protect, 2) Init(-1) Optimization
2412 Use a stack protection method for every function.
2414 fstack-protector-strong
2415 Common Report RejectNegative Var(flag_stack_protect, 3) Init(-1) Optimization
2416 Use a smart stack protection method for certain functions.
2418 fstack-protector-explicit
2419 Common Report RejectNegative Var(flag_stack_protect, 4) Optimization
2420 Use stack protection method only for functions with the stack_protect attribute.
2423 Common RejectNegative Var(flag_stack_usage)
2424 Output stack usage information on a per-function basis.
2428 Does nothing. Preserved for backward compatibility.
2430 ; Nonzero if we should do (language-dependent) alias analysis.
2431 ; Typically, this analysis will assume that expressions of certain
2432 ; types do not alias expressions of certain other types. Only used
2433 ; if alias analysis (in general) is enabled.
2435 Common Report Var(flag_strict_aliasing) Optimization
2436 Assume strict aliasing rules apply.
2440 Treat signed overflow as undefined. Negated as -fwrapv -fwrapv-pointer.
2443 Common Report Var(flag_sync_libcalls) Init(1)
2444 Implement __atomic operations via libcalls to legacy __sync functions.
2447 Common Report Var(flag_syntax_only)
2448 Check for syntax errors, then stop.
2451 Common Report Var(flag_test_coverage)
2452 Create data files needed by \"gcov\".
2455 Common Report Var(flag_thread_jumps) Optimization
2456 Perform jump threading optimizations.
2459 Common Report Var(time_report)
2460 Report the time taken by each compiler pass.
2462 ftime-report-details
2463 Common Report Var(time_report_details)
2464 Record times taken by sub-phases separately.
2467 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2468 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model.
2471 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2474 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2477 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2480 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2483 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2486 Common Report Var(flag_toplevel_reorder) Init(2)
2487 Reorder top level functions, variables, and asms.
2490 Common Report Var(flag_tracer) Optimization
2491 Perform superblock formation via tail duplication.
2494 Common Report Var(flag_trampolines) Init(0)
2495 For targets that normally need trampolines for nested functions, always
2496 generate them instead of using descriptors.
2498 ; Zero means that floating-point math operations cannot generate a
2499 ; (user-visible) trap. This is the case, for example, in nonstop
2500 ; IEEE 754 arithmetic.
2502 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2503 Assume floating-point operations can trap.
2506 Common Report Var(flag_trapv) Optimization
2507 Trap for signed overflow in addition, subtraction and multiplication.
2510 Common Report Var(flag_tree_ccp) Optimization
2511 Enable SSA-CCP optimization on trees.
2514 Common Report Var(flag_tree_bit_ccp) Optimization
2515 Enable SSA-BIT-CCP optimization on trees.
2519 Does nothing. Preserved for backward compatibility.
2522 Common Report Var(flag_tree_ch) Optimization
2523 Enable loop header copying on trees.
2525 ftree-coalesce-inlined-vars
2526 Common Ignore RejectNegative
2527 Does nothing. Preserved for backward compatibility.
2530 Common Report Var(flag_tree_coalesce_vars) Optimization
2531 Enable SSA coalescing of user variables.
2535 Does nothing. Preserved for backward compatibility.
2538 Common Report Var(flag_tree_copy_prop) Optimization
2539 Enable copy propagation on trees.
2541 ftree-store-copy-prop
2543 Does nothing. Preserved for backward compatibility.
2546 Common Report Var(flag_tree_cselim) Init(2) Optimization
2547 Transform condition stores into unconditional ones.
2549 ftree-switch-conversion
2550 Common Report Var(flag_tree_switch_conversion) Optimization
2551 Perform conversions of switch initializations.
2554 Common Report Var(flag_tree_dce) Optimization
2555 Enable SSA dead code elimination optimization on trees.
2557 ftree-dominator-opts
2558 Common Report Var(flag_tree_dom) Optimization
2559 Enable dominator optimizations.
2562 Common Report Var(flag_tree_tail_merge) Optimization
2563 Enable tail merging on trees.
2566 Common Report Var(flag_tree_dse) Optimization
2567 Enable dead store elimination.
2570 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2571 Enable forward propagation on trees.
2574 Common Report Var(flag_tree_fre) Optimization
2575 Enable Full Redundancy Elimination (FRE) on trees.
2578 Common Report Var(flag_optimize_strlen) Optimization
2579 Enable string length optimizations on trees.
2581 fisolate-erroneous-paths-dereference
2582 Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization
2583 Detect paths that trigger erroneous or undefined behavior due to
2584 dereferencing a null pointer. Isolate those paths from the main control
2585 flow and turn the statement with erroneous or undefined behavior into a trap.
2587 fisolate-erroneous-paths-attribute
2588 Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization
2589 Detect paths that trigger erroneous or undefined behavior due to a null value
2590 being used in a way forbidden by a returns_nonnull or nonnull
2591 attribute. Isolate those paths from the main control flow and turn the
2592 statement with erroneous or undefined behavior into a trap.
2594 ftree-loop-distribution
2595 Common Report Var(flag_tree_loop_distribution) Optimization
2596 Enable loop distribution on trees.
2598 ftree-loop-distribute-patterns
2599 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2600 Enable loop distribution for patterns transformed into a library call.
2603 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2604 Enable loop invariant motion on trees.
2607 Common Alias(floop-nest-optimize)
2608 Enable loop nest transforms. Same as -floop-nest-optimize.
2611 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2612 Create canonical induction variables in loops.
2615 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2616 Enable loop optimizations on tree level.
2618 ftree-parallelize-loops=
2619 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) Optimization
2620 -ftree-parallelize-loops=<number> Enable automatic parallelization of loops.
2623 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2624 Enable hoisting loads from conditional pointers.
2627 Common Report Var(flag_tree_pre) Optimization
2628 Enable SSA-PRE optimization on trees.
2631 Common Report Var(flag_tree_partial_pre) Optimization
2632 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination.
2635 Common Report Var(flag_tree_pta) Optimization
2636 Perform function-local points-to analysis on trees.
2639 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2640 Enable reassociation on tree level.
2644 Does nothing. Preserved for backward compatibility.
2647 Common Report Var(flag_tree_sink) Optimization
2648 Enable SSA code sinking on trees.
2651 Common Report Var(flag_tree_slsr) Optimization
2652 Perform straight-line strength reduction.
2655 Common Report Var(flag_tree_sra) Optimization
2656 Perform scalar replacement of aggregates.
2659 Common Report Var(flag_tree_ter) Optimization
2660 Replace temporary expressions in the SSA->normal pass.
2663 Common Report Var(flag_tree_live_range_split) Optimization
2664 Perform live range splitting during the SSA->normal pass.
2667 Common Report Var(flag_tree_vrp) Init(0) Optimization
2668 Perform Value Range Propagation on trees.
2671 Common Report Var(flag_split_paths) Init(0) Optimization
2672 Split paths leading to loop backedges.
2674 funconstrained-commons
2675 Common Var(flag_unconstrained_commons) Optimization
2676 Assume common declarations may be overridden with ones with a larger
2680 Common Report Var(flag_unit_at_a_time) Init(1)
2681 Compile whole compilation unit at a time.
2684 Common Report Var(flag_unroll_loops) Optimization
2685 Perform loop unrolling when iteration count is known.
2688 Common Report Var(flag_unroll_all_loops) Optimization
2689 Perform loop unrolling for all loops.
2691 ; Nonzero means that loop optimizer may assume that the induction variables
2692 ; that control loops do not overflow and that the loops with nontrivial
2693 ; exit condition are not infinite
2694 funsafe-loop-optimizations
2696 Does nothing. Preserved for backward compatibility.
2699 Common Report Var(flag_associative_math) SetByCombined Optimization
2700 Allow optimization for floating-point arithmetic which may change the
2701 result of the operation due to rounding.
2704 Common Report Var(flag_reciprocal_math) SetByCombined Optimization
2705 Same as -fassociative-math for expressions which include division.
2707 ; Nonzero means that unsafe floating-point math optimizations are allowed
2708 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2709 ; are allowed to assume that their arguments and results are "normal"
2710 ; (e.g., nonnegative for SQRT).
2711 funsafe-math-optimizations
2712 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2713 Allow math optimizations that may violate IEEE or ISO standards.
2716 Common Report Var(flag_unswitch_loops) Optimization
2717 Perform loop unswitching.
2720 Common Report Var(flag_split_loops) Optimization
2721 Perform loop splitting.
2724 Common Report Var(flag_unwind_tables) Optimization
2725 Just generate unwind tables for exception handling.
2728 Common Driver Negative(fuse-ld=gold)
2729 Use the bfd linker instead of the default linker.
2732 Common Driver Negative(fuse-ld=bfd)
2733 Use the gold linker instead of the default linker.
2736 Common Driver Negative(fuse-ld=lld)
2737 Use the lld LLVM linker instead of the default linker.
2740 Common Undocumented Var(flag_use_linker_plugin)
2742 ; Positive if we should track variables, negative if we should run
2743 ; the var-tracking pass only to discard debug annotations, zero if
2744 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2745 ; will be set according to optimize, debug_info_level and debug_hooks
2746 ; in process_options ().
2748 Common Report Var(flag_var_tracking) Init(2) PerFunction
2749 Perform variable tracking.
2751 ; Positive if we should track variables at assignments, negative if
2752 ; we should run the var-tracking pass only to discard debug
2753 ; annotations. When flag_var_tracking_assignments ==
2754 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2755 fvar-tracking-assignments
2756 Common Report Var(flag_var_tracking_assignments) Init(2) PerFunction
2757 Perform variable tracking by annotating assignments.
2759 ; Nonzero if we should toggle flag_var_tracking_assignments after
2760 ; processing options and computing its default. */
2761 fvar-tracking-assignments-toggle
2762 Common Report Var(flag_var_tracking_assignments_toggle) PerFunction
2763 Toggle -fvar-tracking-assignments.
2765 ; Positive if we should track uninitialized variables, negative if
2766 ; we should run the var-tracking pass only to discard debug
2767 ; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
2768 ; will be set according to flag_var_tracking.
2769 fvar-tracking-uninit
2770 Common Report Var(flag_var_tracking_uninit) PerFunction
2771 Perform variable tracking and also tag variables that are uninitialized.
2773 ; Alias to enable both -ftree-loop-vectorize and -ftree-slp-vectorize.
2775 Common Report Optimization
2776 Enable vectorization on trees.
2778 ftree-vectorizer-verbose=
2779 Common Joined RejectNegative Ignore
2780 Does nothing. Preserved for backward compatibility.
2782 ftree-loop-vectorize
2783 Common Report Var(flag_tree_loop_vectorize) Optimization EnabledBy(ftree-vectorize)
2784 Enable loop vectorization on trees.
2787 Common Report Var(flag_tree_slp_vectorize) Optimization EnabledBy(ftree-vectorize)
2788 Enable basic block vectorization (SLP) on trees.
2791 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization
2792 -fvect-cost-model=[unlimited|dynamic|cheap] Specifies the cost model for vectorization.
2795 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization
2796 -fsimd-cost-model=[unlimited|dynamic|cheap] Specifies the vectorization cost model for code marked with a simd directive.
2799 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2802 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2805 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2808 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2811 Common Alias(fvect-cost-model=,dynamic,unlimited)
2812 Enables the dynamic vectorizer cost model. Preserved for backward compatibility.
2814 ftree-vect-loop-version
2816 Does nothing. Preserved for backward compatibility.
2819 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2820 Enable copy propagation of scalar-evolution information.
2822 ; -fverbose-asm causes extra commentary information to be produced in
2823 ; the generated assembly code (to make it more readable). This option
2824 ; is generally only of use to those who actually need to read the
2825 ; generated assembly code (perhaps while debugging the compiler itself).
2826 ; -fno-verbose-asm, the default, causes the extra information
2827 ; to not be added and is useful when comparing two assembler files.
2829 Common Report Var(flag_verbose_asm)
2830 Add extra commentary to assembler output.
2833 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2834 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility.
2837 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2840 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2843 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2846 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2849 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2852 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2853 Validate vtable pointers before using them.
2856 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2859 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2862 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2865 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2868 Common Var(flag_vtv_counts)
2869 Output vtable verification counters.
2872 Common Var(flag_vtv_debug)
2873 Output vtable verification pointer sets information.
2876 Common Report Var(flag_value_profile_transformations) Optimization
2877 Use expression value profiles in optimizations.
2880 Common Report Var(flag_web) Init(2) Optimization
2881 Construct webs and split unrelated uses of single variable.
2883 ftree-builtin-call-dce
2884 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2885 Enable conditional dead code elimination for builtin calls.
2888 Common Report Var(flag_whole_program) Init(0)
2889 Perform whole program optimizations.
2892 Common Report Var(flag_wrapv_pointer) Optimization
2893 Assume pointer overflow wraps around.
2896 Common Report Var(flag_wrapv) Optimization
2897 Assume signed arithmetic overflow wraps around.
2899 fzero-initialized-in-bss
2900 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2901 Put zero initialized data in the bss section.
2904 Common Driver RejectNegative JoinedOrMissing
2905 Generate debug information in default format.
2908 Common Driver Var(dwarf2out_as_loc_support) Init(2)
2909 Assume assembler support for (DWARF2+) .loc directives
2912 Common Driver Var(dwarf2out_as_locview_support) Init(2)
2913 Assume assembler support for view in (DWARF2+) .loc directives
2916 Common Driver Deprecated
2917 Does nothing. Preserved for backward compatibility.
2920 Common Driver Deprecated
2921 Does nothing. Preserved for backward compatibility.
2924 Common Driver Deprecated
2925 Does nothing. Preserved for backward compatibility.
2928 Common Driver Deprecated
2929 Does nothing. Preserved for backward compatibility.
2932 Common Driver Var(debug_column_info,1) Init(1)
2933 Record DW_AT_decl_column and DW_AT_call_column in DWARF.
2936 Common Driver JoinedOrMissing Negative(gdwarf-)
2937 Generate debug information in default version of DWARF format.
2940 Common Driver Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2941 Generate debug information in DWARF v2 (or later) format.
2944 Common Driver JoinedOrMissing
2945 Generate debug information in default extended format.
2948 Common Driver Var(debug_inline_points) Init(2)
2949 Generate extended entry point information for inlined functions
2951 ginternal-reset-location-views
2952 Common Driver Var(debug_internal_reset_location_views) Init(2)
2953 Compute locview reset points based on insn length estimates
2956 RejectNegative Joined Undocumented
2957 ; Catch the gno- prefix, so it doesn't backtrack to g<level>.
2960 Common Driver Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
2961 Don't generate DWARF pubnames and pubtypes sections.
2964 Common Driver Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
2965 Generate DWARF pubnames and pubtypes sections.
2968 Common Driver Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
2969 Generate DWARF pubnames and pubtypes sections with GNU extensions.
2971 grecord-gcc-switches
2972 Common Driver Var(dwarf_record_gcc_switches) Init(1)
2973 Record gcc command line switches in DWARF DW_AT_producer.
2976 Common Driver Var(dwarf_split_debug_info) Init(0)
2977 Generate debug information in separate .dwo files.
2980 Common Driver JoinedOrMissing Negative(gstabs+)
2981 Generate debug information in STABS format.
2984 Common Driver JoinedOrMissing Negative(gvms)
2985 Generate debug information in extended STABS format.
2987 gstatement-frontiers
2988 Common Driver Var(debug_nonbind_markers_p) Init(2)
2989 Emit progressive recommended breakpoint locations.
2992 Common Driver Report Var(dwarf_strict) Init(0)
2993 Don't emit DWARF additions beyond selected version.
2996 Common Driver Report Var(flag_describe_dies) Init(0)
2997 Add description attributes to some DWARF DIEs that have no name attribute.
3000 Common Driver Report Var(flag_gtoggle)
3001 Toggle debug information generation.
3003 gvariable-location-views
3004 Common Driver Var(debug_variable_location_views, 1) Init(2)
3005 Augment variable location lists with progressive views.
3007 gvariable-location-views=incompat5
3008 Common Driver RejectNegative Var(debug_variable_location_views, -1) Init(2)
3011 Common Driver JoinedOrMissing Negative(gxcoff)
3012 Generate debug information in VMS format.
3015 Common Driver JoinedOrMissing Negative(gxcoff+)
3016 Generate debug information in XCOFF format.
3019 Common Driver JoinedOrMissing Negative(gdwarf)
3020 Generate debug information in extended XCOFF format.
3023 Name(compressed_debug_sections) Type(int)
3025 ; Since -gz= is completely handled in specs, the values aren't used and we
3026 ; assign arbitrary constants.
3028 Enum(compressed_debug_sections) String(none) Value(0)
3031 Enum(compressed_debug_sections) String(zlib) Value(1)
3034 Enum(compressed_debug_sections) String(zlib-gnu) Value(2)
3038 Generate compressed debug sections.
3041 Common Driver RejectNegative Joined Enum(compressed_debug_sections)
3042 -gz=<format> Generate compressed debug sections in format <format>.
3045 Driver Joined Separate
3048 Common Joined Var(plugindir_string) Init(0)
3049 -iplugindir=<dir> Set <dir> to be the default plugin directory.
3052 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
3053 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory.
3056 Driver Joined Separate
3061 no-canonical-prefixes
3077 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
3078 -o <file> Place output into <file>.
3081 Common Var(profile_flag)
3082 Enable function profiling.
3085 Driver Var(pass_exit_codes)
3088 Common Alias(Wpedantic)
3091 Common Var(flag_pedantic_errors)
3092 Like -pedantic but issue them as errors.
3098 Driver Var(use_pipes)
3101 Driver JoinedOrMissing Var(print_file_name)
3103 print-libgcc-file-name
3106 print-multi-directory
3107 Driver Var(print_multi_directory)
3110 Driver Var(print_multi_lib)
3112 print-multi-os-directory
3113 Driver Var(print_multi_os_directory)
3116 Driver Var(print_multiarch)
3119 Driver JoinedOrMissing Var(print_prog_name)
3122 Driver Var(print_search_dirs)
3125 Driver Var(print_sysroot)
3127 print-sysroot-headers-suffix
3128 Driver Var(print_sysroot_headers_suffix)
3131 Common Var(quiet_flag) RejectDriver
3132 Do not display functions compiled or elapsed time.
3150 Driver Var(report_times)
3153 Driver JoinedOrMissing
3156 Driver Joined Separate
3160 ; C option, but driver must not handle as "-u ndef".
3163 Common Driver Var(verbose_flag)
3164 Enable verbose output.
3167 Common Var(version_flag) RejectDriver
3168 Display the compiler's version.
3171 Common Var(inhibit_warnings)
3175 Driver Separate Var(wrapper_string)
3178 Driver Joined Separate
3181 Driver RejectNegative Negative(static-pie)
3182 Create a shared library.
3188 Driver Separate Alias(specs=)
3201 ; Documented for Fortran, but always accepted by driver.
3208 ; Documented for Go, but always accepted by driver.
3226 Driver RejectNegative Negative(shared)
3227 Don't create a dynamically linked position independent executable.
3230 Driver RejectNegative Negative(no-pie)
3231 Create a dynamically linked position independent executable.
3234 Driver RejectNegative Negative(pie)
3235 Create a static position independent executable.
3238 Driver Joined Separate
3241 Common Report Var(flag_ipa_ra) Optimization
3242 Use caller save register across calls if possible.
3244 ; This comment is to ensure we retain the blank line above.