1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003-2013 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 ; 0 means straightforward implementation of complex divide acceptable.
50 ; 1 means wide ranges of inputs must work for complex divide.
51 ; 2 means C99-like requirements for complex multiply and divide.
53 int flag_complex_method = 1
55 ; Nonzero if subexpressions must be evaluated from left-to-right.
57 int flag_evaluation_order = 0
59 ; Language specific warning pass for unused results.
61 bool flag_warn_unused_result = false
66 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
70 ; True to warn about any objects definitions whose size is larger
71 ; than N bytes. Also want about function definitions whose returned
72 ; values are larger than N bytes, where N is 'larger_than_size'.
77 HOST_WIDE_INT larger_than_size
79 ; True to warn about any function whose frame size is larger
82 bool warn_frame_larger_than
85 HOST_WIDE_INT frame_larger_than_size
87 ; Nonzero means we should be saving declaration info into a .X file.
89 int flag_gen_aux_info = 0
91 ; Nonzero if we are compiling code for a shared library, zero for
96 ; These two are really VEC(char_p,heap) *.
99 void *flag_instrument_functions_exclude_functions
102 void *flag_instrument_functions_exclude_files
104 ; Generic structs (e.g. templates not explicitly specialized)
105 ; may not have a compilation unit associated with them, and so
106 ; may need to be treated differently from ordinary structs.
108 ; Structs only handled by reference (indirectly), will also usually
109 ; not need as much debugging information.
112 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
115 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
117 ; True if we should exit after parsing options.
119 bool exit_after_options
121 ; Type(s) of debugging information we are producing (if any). See
122 ; flag-types.h for the definitions of the different possible types of
123 ; debugging information.
125 enum debug_info_type write_symbols = NO_DEBUG
127 ; Level of debugging information we are producing. See flag-types.h
128 ; for the definitions of the different possible levels.
130 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
132 ; Nonzero means use GNU-only extensions in the generated symbolic
133 ; debugging information. Currently, this only has an effect when
134 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
136 bool use_gnu_debug_info_extensions
138 ; Original value of maximum field alignment in bytes, specified via
139 ; -fpack-struct=<value>.
141 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
143 ; Type of stack check.
145 enum stack_check_type flag_stack_check = NO_STACK_CHECK
147 ; True if stack usage information needs to be computed.
149 bool flag_stack_usage_info = false
151 ; -dA causes debug commentary information to be produced in
152 ; the generated assembly code (to make it more readable). This option
153 ; is generally only of use to those who actually need to read the
154 ; generated assembly code (perhaps while debugging the compiler itself).
155 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
156 ; to be a catchall for printing debug information in the assembler file.
160 ; -dP causes the rtl to be emitted as a comment in assembly.
162 int flag_dump_rtl_in_asm
164 ; Whether -da was passed (used only in handle_common_deferred_options).
166 bool flag_dump_all_passed
168 ; Other flags saying which kinds of debugging dump have been requested.
171 int rtl_dump_and_exit
174 int flag_print_asm_name
176 ; Name of top-level original source file (what was input to cpp).
177 ; This comes from the #-command at the beginning of the actual input.
178 ; If there isn't any there, then this is the cc1 input file name.
180 const char *main_input_filename
182 ; Pointer to base name in main_input_filename, with directories and a
183 ; single final extension removed, and the length of this base
187 const char *main_input_basename
190 int main_input_baselength
192 ; Which options have been printed by --help.
196 ; Which enums have been printed by --help. 0 = not printed, no
197 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
200 char *help_enum_printed
202 ; The number of columns for --help output.
204 unsigned int help_columns
206 ; Whether this options structure has been through finish_options
208 bool flag_opts_finished
210 ; What the sanitizer should instrument
212 unsigned int flag_sanitize
224 Driver Alias(coverage)
230 Common Separate Alias(d)
233 Common Joined Alias(d)
236 Common Separate Alias(dumpbase)
239 Common Separate Alias(dumpdir)
242 Driver Separate Alias(e)
245 Driver Joined Alias(e)
248 Common Warning Alias(Wextra)
251 Driver Separate Alias(Xassembler)
254 Driver JoinedOrMissing Alias(Xassembler)
257 Driver Separate Alias(Xlinker)
260 Driver JoinedOrMissing Alias(Xlinker)
263 Driver Separate Alias(u)
266 Driver Joined Alias(u)
269 Common Driver Var(help_flag)
270 Display this information
273 Common Driver Report Joined
274 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
277 Driver Separate Alias(x)
280 Driver Joined Alias(x)
283 Driver Separate Alias(L)
286 Driver Joined Alias(L)
288 -no-canonical-prefixes
289 Driver Alias(no-canonical-prefixes)
291 -no-standard-libraries
292 Driver Alias(nostdlib)
295 Driver Var(no_sysroot_suffix)
304 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
307 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
310 Driver Alias(pass-exit-codes)
313 Common Alias(Wpedantic)
316 Common Alias(pedantic-errors)
325 Driver Separate Alias(B)
328 Driver JoinedOrMissing Alias(B)
334 Driver Separate Alias(print-file-name=)
337 Driver JoinedOrMissing Alias(print-file-name=)
339 -print-libgcc-file-name
340 Driver Alias(print-libgcc-file-name)
342 -print-multi-directory
343 Driver Alias(print-multi-directory)
346 Driver Alias(print-multi-lib)
348 -print-multi-os-directory
349 Driver Alias(print-multi-os-directory)
352 Driver Alias(print-multiarch)
355 Driver Separate Alias(print-prog-name=)
358 Driver JoinedOrMissing Alias(print-prog-name=)
361 Driver Alias(print-search-dirs)
364 Driver Alias(print-sysroot)
366 -print-sysroot-headers-suffix
367 Driver Alias(print-sysroot-headers-suffix)
373 Driver Alias(save-temps)
379 Driver Separate Alias(specs=)
382 Driver Joined Alias(specs=)
388 Driver Alias(symbolic)
392 Alias for --help=target
400 ;; The driver used to convert options such as --help into forms such
401 ;; as -fhelp; the following four entries are for compatibility with
402 ;; any direct uses of those (undocumented) -f forms
404 Common Driver Alias(-help)
407 Common Driver Joined Alias(-help=)
410 Common Driver Alias(-target-help)
413 Common Driver Alias(-version)
417 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
420 Common Joined Alias(-param)
423 Driver Separate Alias(-sysroot=)
426 Driver JoinedOrMissing
432 Driver Joined Separate
438 Driver Joined Separate
444 Common JoinedOrMissing Optimization
445 -O<number> Set optimization level to <number>
449 Optimize for space rather than speed
453 Optimize for speed disregarding exact standards compliance
457 Optimize for debugging experience rather than speed or size
469 Driver Joined Separate
475 Driver Joined Separate
496 Common RejectNegative Warning Alias(Wextra)
497 This switch is deprecated; use -Wextra instead
500 Driver JoinedOrMissing
503 Driver JoinedOrMissing
506 Driver JoinedOrMissing
509 Common Var(warn_aggregate_return) Warning
510 Warn about returning structures, unions or arrays
512 Waggressive-loop-optimizations
513 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
514 Warn if a loop with constant number of iterations triggers undefined behavior
517 Common Var(warn_array_bounds) Warning
518 Warn if an array is accessed out of bounds
521 Common Var(warn_attributes) Init(1) Warning
522 Warn about inappropriate attribute usage
525 Common Var(warn_cast_align) Warning
526 Warn about pointer casts which increase alignment
529 Common Var(warn_cpp) Init(1) Warning
530 Warn when a #warning directive is encountered
532 Wdeprecated-declarations
533 Common Var(warn_deprecated_decl) Init(1) Warning
534 Warn about uses of __attribute__((deprecated)) declarations
536 Wdisabled-optimization
537 Common Var(warn_disabled_optimization) Warning
538 Warn when an optimization pass is disabled
541 Common Var(warnings_are_errors)
542 Treat all warnings as errors
546 Treat specified warning as error
549 Common Var(extra_warnings) Warning
550 Print extra (possibly unwanted) warnings
553 Common Var(flag_fatal_errors)
554 Exit on the first error occurred
557 Common RejectNegative Joined UInteger
558 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
561 Common Var(warn_free_nonheap_object) Init(1) Warning
562 Warn when attempting to free a non-heap object
565 Common Var(warn_inline) Warning
566 Warn when an inlined function cannot be inlined
568 Winvalid-memory-model
569 Common Var(warn_invalid_memory_model) Init(1) Warning
570 Warn when an atomic memory model parameter is known to be outside the valid range.
573 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
576 Common RejectNegative Joined UInteger Warning
577 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
579 Wunsafe-loop-optimizations
580 Common Var(warn_unsafe_loop_optimizations) Warning
581 Warn if the loop cannot be optimized due to nontrivial assumptions.
584 Common Alias(Wsuggest-attribute=noreturn)
587 Common Var(warn_overflow) Init(1) Warning
588 Warn about overflow in arithmetic expressions
591 Common Var(warn_packed) Warning
592 Warn when the packed attribute has no effect on struct layout
595 Common Var(warn_padded) Warning
596 Warn when padding is required to align structure members
599 Common Var(pedantic) Warning
600 Issue warnings needed for strict compliance to the standard
603 Common Var(warn_shadow) Warning
604 Warn when one local variable shadows another
607 Common Var(warn_stack_protect) Warning
608 Warn when not issuing stack smashing protection for some reason
611 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
612 Warn if stack usage might be larger than specified amount
616 Warn about code which might break strict aliasing rules
619 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
620 Warn about code which might break strict aliasing rules
624 Warn about optimizations that assume that signed overflow is undefined
627 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
628 Warn about optimizations that assume that signed overflow is undefined
630 Wsuggest-attribute=const
631 Common Var(warn_suggest_attribute_const) Warning
632 Warn about functions which might be candidates for __attribute__((const))
634 Wsuggest-attribute=pure
635 Common Var(warn_suggest_attribute_pure) Warning
636 Warn about functions which might be candidates for __attribute__((pure))
638 Wsuggest-attribute=noreturn
639 Common Var(warn_suggest_attribute_noreturn) Warning
640 Warn about functions which might be candidates for __attribute__((noreturn))
643 Common Var(warn_system_headers) Warning
644 Do not suppress warnings from system headers
647 Common Var(warn_trampolines) Warning
648 Warn whenever a trampoline is generated
651 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
652 Warn if a comparison is always true or always false due to the limited range of the data type
655 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
656 Warn about uninitialized automatic variables
659 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
660 Warn about maybe uninitialized automatic variables
664 Does nothing. Preserved for backward compatibility.
667 Common Var(warn_unused) Init(0) Warning
668 Enable all -Wunused- warnings
670 Wunused-but-set-parameter
671 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
672 Warn when a function parameter is only set, otherwise unused
674 Wunused-but-set-variable
675 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
676 Warn when a variable is only set, otherwise unused
679 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
680 Warn when a function is unused
683 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
684 Warn when a label is unused
687 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
688 Warn when a function parameter is unused
691 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
692 Warn when an expression value is unused
695 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
696 Warn when a variable is unused
699 Common Var(warn_coverage_mismatch) Init(1) Warning
700 Warn in case profiles in -fprofile-use do not match
702 Wvector-operation-performance
703 Common Var(warn_vector_operation_performance) Warning
704 Warn when a vector operation is compiled outside the SIMD
719 Common Separate Var(aux_info_file_name)
720 -aux-info <file> Emit declaration information into <file>
723 Common Joined Alias(aux-info)
726 Common Separate RejectDriver Var(aux_base_name)
729 Common Separate RejectDriver
739 -d<letters> Enable dumps from specific passes of the compiler
742 Common Separate Var(dump_base_name)
743 -dumpbase <file> Set the file basename to be used for dumps
746 Common Separate Var(dump_dir_name)
747 -dumpdir <dir> Set the directory name to be used for dumps
759 Driver Joined Separate
761 ; This option has historically been passed down to the linker by an
762 ; accident of a %{e*} spec, so ensure it continues to be passed down
763 ; as a single option. The supported option for this purpose is
764 ; -rdynamic. See PR 47390.
768 ; The version of the C++ ABI in use. The following values are allowed:
770 ; 0: The version of the ABI believed most conformant with the C++ ABI
771 ; specification. This ABI may change as bugs are discovered and fixed.
772 ; Therefore, 0 will not necessarily indicate the same ABI in different
775 ; 1: The version of the ABI first used in G++ 3.2.
777 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
779 ; 3: The version of the ABI that fixes the missing underscore
780 ; in template non-type arguments of pointer type.
782 ; 4: The version of the ABI that introduces unambiguous mangling of
783 ; vector types. First selectable in G++ 4.5.
785 ; 5: The version of the ABI that ignores attribute const/noreturn
786 ; in function pointer mangling, and corrects mangling of decltype and
787 ; function parameters used in other parameters and the return type.
788 ; First selectable in G++ 4.6.
790 ; 6: The version of the ABI that doesn't promote scoped enums to int and
791 ; changes the mangling of template argument packs, const/static_cast,
792 ; prefix ++ and --, and a class scope function used as a template
794 ; First selectable in G++ 4.7.
796 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
797 ; corrects the mangling of lambdas in default argument scope.
798 ; First selectable in G++ 4.8.
800 ; 8: The version of the ABI that corrects the substitution behavior of
801 ; function types with function-cv-qualifiers.
802 ; First selectable in G++ 4.9.
804 ; Additional positive integers will be assigned as new versions of
805 ; the ABI become the default version of the ABI.
807 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
809 faggressive-loop-optimizations
810 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
811 Aggressively optimize loops using language constraints
814 Common Report Var(align_functions,0) Optimization UInteger
815 Align the start of functions
818 Common RejectNegative Joined UInteger Var(align_functions)
821 Common Report Var(align_jumps,0) Optimization UInteger
822 Align labels which are only reached by jumping
825 Common RejectNegative Joined UInteger Var(align_jumps)
828 Common Report Var(align_labels,0) Optimization UInteger
832 Common RejectNegative Joined UInteger Var(align_labels)
835 Common Report Var(align_loops,0) Optimization UInteger
836 Align the start of loops
839 Common RejectNegative Joined UInteger Var(align_loops)
843 Does nothing. Preserved for backward compatibility.
847 Does nothing. Preserved for backward compatibility.
849 fargument-noalias-global
851 Does nothing. Preserved for backward compatibility.
853 fargument-noalias-anything
855 Does nothing. Preserved for backward compatibility.
858 Common Driver Report Joined
859 Select what to sanitize
861 fasynchronous-unwind-tables
862 Common Report Var(flag_asynchronous_unwind_tables) Optimization
863 Generate unwind tables that are exact at each instruction boundary
866 Common Report Var(flag_auto_inc_dec) Init(1)
867 Generate auto-inc/dec instructions
869 ; -fcheck-bounds causes gcc to generate array bounds checks.
870 ; For C, C++ and ObjC: defaults off.
871 ; For Java: defaults to on.
872 ; For Fortran: defaults to off.
874 Common Report Var(flag_bounds_check)
875 Generate code to check bounds before indexing arrays
878 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
879 Replace add, compare, branch with branch on count register
881 fbranch-probabilities
882 Common Report Var(flag_branch_probabilities) Optimization
883 Use profiling information for branch probabilities
885 fbranch-target-load-optimize
886 Common Report Var(flag_branch_target_load_optimize) Optimization
887 Perform branch target load optimization before prologue / epilogue threading
889 fbranch-target-load-optimize2
890 Common Report Var(flag_branch_target_load_optimize2) Optimization
891 Perform branch target load optimization after prologue / epilogue threading
894 Common Report Var(flag_btr_bb_exclusive) Optimization
895 Restrict target load migration not to re-use registers in any basic block
898 Common Joined RejectNegative Var(common_deferred_options) Defer
899 -fcall-saved-<register> Mark <register> as being preserved across functions
902 Common Joined RejectNegative Var(common_deferred_options) Defer
903 -fcall-used-<register> Mark <register> as being corrupted by function calls
905 ; Nonzero for -fcaller-saves: allocate values in regs that need to
906 ; be saved across function calls, if that produces overall better code.
907 ; Optional now, so people can test it.
909 Common Report Var(flag_caller_saves) Optimization
910 Save registers around function calls
913 Common Report Var(flag_check_data_deps)
914 Compare the results of several data dependence analyzers.
917 Common Var(flag_check_new)
918 Check the return value of new in C++
920 fcombine-stack-adjustments
921 Common Report Var(flag_combine_stack_adjustments) Optimization
922 Looks for opportunities to reduce stack adjustments and stack references.
925 Common Report Var(flag_no_common,0) Optimization
926 Do not put uninitialized globals in the common section
930 ; Converted by the driver to -fcompare-debug= options.
933 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
934 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
936 fcompare-debug-second
937 Common Driver RejectNegative Var(flag_compare_debug)
938 Run only the second compilation of -fcompare-debug
941 Common Report Var(flag_compare_elim_after_reload) Optimization
942 Perform comparison elimination after register allocation has finished
945 Common Var(flag_conserve_stack) Optimization
946 Do not perform optimizations increasing noticeably stack usage
949 Common Report Var(flag_cprop_registers) Optimization
950 Perform a register copy-propagation optimization pass
953 Common Report Var(flag_crossjumping) Optimization
954 Perform cross-jumping optimization
957 Common Report Var(flag_cse_follow_jumps) Optimization
958 When running CSE, follow jumps to their targets
962 Does nothing. Preserved for backward compatibility.
965 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
966 Omit range reduction step when performing complex division
969 Common Report Var(flag_cx_fortran_rules) Optimization
970 Complex multiplication and division follow Fortran rules
973 Common Report Var(flag_data_sections) Optimization
974 Place data items into their own section
977 Common Report Var(common_deferred_options) Defer
978 List all available debugging counters with their limits and counts.
981 Common RejectNegative Joined Var(common_deferred_options) Defer
982 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
985 Common Joined RejectNegative Var(common_deferred_options) Defer
986 Map one directory name to another in debug information
989 Common Report Var(flag_debug_types_section) Init(0)
990 Output .debug_types section when using DWARF v4 debuginfo.
992 ; Nonzero for -fdefer-pop: don't pop args after each function call
993 ; instead save them up to pop many calls' args with one insns.
995 Common Report Var(flag_defer_pop) Optimization
996 Defer popping functions args from stack until later
999 Common Report Var(flag_delayed_branch) Optimization
1000 Attempt to fill delay slots of branch instructions
1002 fdelete-dead-exceptions
1003 Common Report Var(flag_delete_dead_exceptions) Init(0)
1004 Delete dead instructions that may throw exceptions
1006 fdelete-null-pointer-checks
1007 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
1008 Delete useless null pointer checks
1010 fdevirtualize-speculatively
1011 Common Report Var(flag_devirtualize_speculatively) Optimization
1012 Perform speculative devirtualization
1015 Common Report Var(flag_devirtualize) Optimization
1016 Try to convert virtual calls to direct ones.
1018 fdiagnostics-show-location=
1019 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1020 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
1022 ; Required for these enum values.
1027 Name(diagnostic_prefixing_rule) Type(int)
1030 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1033 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1035 fdiagnostics-show-caret
1036 Common Var(flag_diagnostics_show_caret) Init(1)
1037 Show the source line with a caret indicating the column
1040 Common Alias(fdiagnostics-color=,always,never)
1044 Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1045 -fdiagnostics-color=[never|always|auto] Colorize diagnostics
1047 ; Required for these enum values.
1052 Name(diagnostic_color_rule) Type(int)
1055 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1058 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1061 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1063 fdiagnostics-show-option
1064 Common Var(flag_diagnostics_show_option) Init(1)
1065 Amend appropriate diagnostic messages with the command line option that controls them
1068 Common Joined RejectNegative Var(common_deferred_options) Defer
1069 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1072 Common Joined RejectNegative Var(common_deferred_options) Defer
1073 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1076 Common Joined RejectNegative Var(common_deferred_options) Defer
1077 -fdump-<type> Dump various compiler internals to a file
1080 Driver RejectNegative
1083 Common RejectNegative Joined Var(flag_dump_final_insns)
1084 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1087 Common RejectNegative Joined Var(flag_dump_go_spec)
1088 -fdump-go-spec=filename Write all declarations to file as Go code
1091 Common Report Var(flag_dump_noaddr)
1092 Suppress output of addresses in debugging dumps
1095 Common Var(flag_dump_passes) Init(0)
1096 Dump optimization passes
1099 Common Report Var(flag_dump_unnumbered)
1100 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1102 fdump-unnumbered-links
1103 Common Report Var(flag_dump_unnumbered_links)
1104 Suppress output of previous and next insn numbers in debugging dumps
1107 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1108 Enable CFI tables via GAS assembler directives.
1111 Common Report Var(flag_early_inlining) Init(1) Optimization
1112 Perform early inlining
1114 feliminate-dwarf2-dups
1115 Common Report Var(flag_eliminate_dwarf2_dups)
1116 Perform DWARF2 duplicate elimination
1119 Common Report Var(flag_ipa_sra) Init(0) Optimization
1120 Perform interprocedural reduction of aggregates
1122 feliminate-unused-debug-symbols
1123 Common Report Var(flag_debug_only_used_symbols)
1124 Perform unused type elimination in debug info
1126 feliminate-unused-debug-types
1127 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1128 Perform unused type elimination in debug info
1130 femit-class-debug-always
1131 Common Report Var(flag_emit_class_debug_always) Init(0)
1132 Do not suppress C++ class debug information.
1135 Common Report Var(flag_exceptions) Optimization
1136 Enable exception handling
1138 fexpensive-optimizations
1139 Common Report Var(flag_expensive_optimizations) Optimization
1140 Perform a number of minor, expensive optimizations
1143 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1144 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1147 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1150 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1153 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1159 Common Var(flag_fat_lto_objects) Init(1)
1160 Output lto objects containing both the intermediate language and binary output.
1163 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1164 Assume no NaNs or infinities are generated
1167 Common Joined RejectNegative Var(common_deferred_options) Defer
1168 -ffixed-<register> Mark <register> as being unavailable to the compiler
1171 Common Report Var(flag_float_store) Optimization
1172 Don't allocate floats and doubles in extended-precision registers
1176 Does nothing. Preserved for backward compatibility.
1179 Common Report Var(flag_forward_propagate) Optimization
1180 Perform a forward propagation pass on RTL
1183 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1184 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1187 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1190 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1192 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1194 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1197 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1199 ; Nonzero means don't put addresses of constant functions in registers.
1200 ; Used for compiling the Unix kernel, where strange substitutions are
1201 ; done on the assembly output.
1203 Common Report Var(flag_no_function_cse,0)
1204 Allow function addresses to be held in registers
1207 Common Report Var(flag_function_sections)
1208 Place each function into its own section
1211 Common Report Var(flag_gcse) Optimization
1212 Perform global common subexpression elimination
1215 Common Report Var(flag_gcse_lm) Init(1) Optimization
1216 Perform enhanced load motion during global common subexpression elimination
1219 Common Report Var(flag_gcse_sm) Init(0) Optimization
1220 Perform store motion after global common subexpression elimination
1223 Common Report Var(flag_gcse_las) Init(0) Optimization
1224 Perform redundant load after store elimination in global common subexpression
1228 Common Report Var(flag_gcse_after_reload) Optimization
1229 Perform global common subexpression elimination after register allocation
1232 ; This option is not documented yet as its semantics will change.
1234 Common Report Var(flag_graphite)
1235 Enable in and out of Graphite representation
1238 Common Report Var(flag_graphite_identity) Optimization
1239 Enable Graphite Identity transformation
1241 fhoist-adjacent-loads
1242 Common Report Var(flag_hoist_adjacent_loads) Optimization
1243 Enable hoisting adjacent loads to encourage generating conditional move
1246 floop-parallelize-all
1247 Common Report Var(flag_loop_parallelize_all) Optimization
1248 Mark all loops as parallel
1251 Common Report Var(flag_loop_strip_mine) Optimization
1252 Enable Loop Strip Mining transformation
1255 Common Report Var(flag_loop_interchange) Optimization
1256 Enable Loop Interchange transformation
1259 Common Report Var(flag_loop_block) Optimization
1260 Enable Loop Blocking transformation
1263 Common Report Var(flag_tm)
1264 Enable support for GNU transactional memory
1268 Does nothing. Preserved for backward compatibility.
1271 Common Report Var(flag_loop_optimize_isl) Optimization
1272 Enable the ISL based loop nest optimizer
1274 fstrict-volatile-bitfields
1275 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1276 Force bitfield accesses to match their type width
1278 fguess-branch-probability
1279 Common Report Var(flag_guess_branch_prob) Optimization
1280 Enable guessing of branch probabilities
1282 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1283 ; Generate position-independent code for executables if possible
1284 ; On SVR4 targets, it also controls whether or not to emit a
1285 ; string identifying the compiler.
1287 Common Report Var(flag_no_ident,0)
1288 Process #ident directives
1291 Common Report Var(flag_if_conversion) Optimization
1292 Perform conversion of conditional jumps to branchless equivalents
1295 Common Report Var(flag_if_conversion2) Optimization
1296 Perform conversion of conditional jumps to conditional execution
1299 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL)
1300 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1303 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1306 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1309 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1312 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1314 ftree-loop-if-convert
1315 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1316 Convert conditional jumps in innermost loops to branchless equivalents
1318 ftree-loop-if-convert-stores
1319 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1320 Also if-convert conditional jumps containing memory writes
1322 ; -finhibit-size-directive inhibits output of .size for ELF.
1323 ; This is used only for compiling crtstuff.c,
1324 ; and it may be extended to other effects
1325 ; needed for crtstuff.c on other systems.
1326 finhibit-size-directive
1327 Common Report Var(flag_inhibit_size_directive)
1328 Do not generate .size directives
1331 Common Report Var(flag_indirect_inlining)
1332 Perform indirect inlining
1334 ; General flag to enable inlining. Specifying -fno-inline will disable
1335 ; all inlining apart from always-inline functions.
1337 Common Report Var(flag_no_inline,0) Init(0) Optimization
1338 Enable inlining of function declared \"inline\", disabling disables all inlining
1340 finline-small-functions
1341 Common Report Var(flag_inline_small_functions) Optimization
1342 Integrate functions into their callers when code size is known not to grow
1345 Common Report Var(flag_inline_functions) Optimization
1346 Integrate functions not declared \"inline\" into their callers when profitable
1348 finline-functions-called-once
1349 Common Report Var(flag_inline_functions_called_once) Optimization
1350 Integrate functions only required by their single caller
1353 Common RejectNegative Joined Alias(finline-limit=)
1356 Common RejectNegative Joined UInteger
1357 -finline-limit=<number> Limit the size of inlined functions to <number>
1360 Common Report Var(flag_inline_atomics) Init(1) Optimization
1361 Inline __atomic operations when a lock free instruction sequence is available.
1363 finstrument-functions
1364 Common Report Var(flag_instrument_function_entry_exit)
1365 Instrument function entry and exit with profiling calls
1367 finstrument-functions-exclude-function-list=
1368 Common RejectNegative Joined
1369 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1371 finstrument-functions-exclude-file-list=
1372 Common RejectNegative Joined
1373 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1376 Common Report Var(flag_ipa_cp) Optimization
1377 Perform interprocedural constant propagation
1380 Common Report Var(flag_ipa_cp_clone) Optimization
1381 Perform cloning to make Interprocedural constant propagation stronger
1384 Common Report Var(flag_ipa_profile) Init(0) Optimization
1385 Perform interprocedural profile propagation
1388 Common Report Var(flag_ipa_pta) Init(0) Optimization
1389 Perform interprocedural points-to analysis
1392 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1393 Discover pure and const functions
1396 Common Report Var(flag_ipa_reference) Init(0) Optimization
1397 Discover readonly and non addressable static variables
1401 Does nothing. Preserved for backward compatibility.
1405 Does nothing. Preserved for backward compatibility.
1408 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1409 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1412 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1415 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1418 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1421 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1422 -fira-region=[one|all|mixed] Set regions for IRA
1425 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1428 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1431 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1434 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1437 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1438 Use IRA based register pressure calculation
1439 in RTL hoist optimizations.
1442 Common Report Var(flag_ira_loop_pressure)
1443 Use IRA based register pressure calculation
1444 in RTL loop optimizations.
1446 fira-share-save-slots
1447 Common Report Var(flag_ira_share_save_slots) Init(1)
1448 Share slots for saving different hard registers.
1450 fira-share-spill-slots
1451 Common Report Var(flag_ira_share_spill_slots) Init(1)
1452 Share stack slots for spilled pseudo-registers.
1455 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1456 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1459 Common Report Var(flag_ivopts) Init(1) Optimization
1460 Optimize induction variables on trees
1463 Common Var(flag_jump_tables) Init(1) Optimization
1464 Use jump tables for sufficiently large switch statements
1466 fkeep-inline-functions
1467 Common Report Var(flag_keep_inline_functions)
1468 Generate code for functions even if they are fully inlined
1471 Common Report Var(flag_keep_static_consts) Init(1)
1472 Emit static const variables even if they are not used
1475 Common Report Var(flag_leading_underscore) Init(-1)
1476 Give external symbols a leading underscore
1480 Does nothing. Preserved for backward compatibility.
1484 Enable link-time optimization.
1487 Common RejectNegative Joined Var(flag_lto)
1488 Link-time optimization with number of parallel jobs or jobserver.
1491 Common Var(flag_lto_partition_1to1)
1492 Partition symbols and vars at linktime based on object files they originate from
1494 flto-partition=balanced
1495 Common Var(flag_lto_partition_balanced)
1496 Partition functions and vars at linktime into approximately same sized buckets
1499 Common Var(flag_lto_partition_max)
1500 Put every symbol into separate partition
1503 Common Var(flag_lto_partition_none)
1504 Disable partioning and streaming
1506 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1507 flto-compression-level=
1508 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1509 -flto-compression-level=<number> Use zlib compression level <number> for IL
1512 Common Report Var(flag_lto_report) Init(0)
1513 Report various link-time optimization statistics
1516 Common Report Var(flag_lto_report_wpa) Init(0)
1517 Report various link-time optimization statistics for WPA only
1520 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1521 Set errno after built-in math functions
1524 Common Joined RejectNegative UInteger Var(flag_max_errors)
1525 -fmax-errors=<number> Maximum number of errors to report
1528 Common Report Var(mem_report)
1529 Report on permanent memory allocation
1532 Common Report Var(mem_report_wpa)
1533 Report on permanent memory allocation in WPA only
1535 ; This will attempt to merge constant section constants, if 1 only
1536 ; string constants and constants from constant pool, if 2 also constant
1538 fmerge-all-constants
1539 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1540 Attempt to merge identical constants and constant variables
1543 Common Report Var(flag_merge_constants,1) Optimization
1544 Attempt to merge identical constants across compilation units
1546 fmerge-debug-strings
1547 Common Report Var(flag_merge_debug_strings) Init(1)
1548 Attempt to merge identical debug strings across compilation units
1551 Common RejectNegative Joined UInteger
1552 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1555 Common Report Var(flag_modulo_sched) Optimization
1556 Perform SMS based modulo scheduling before the first scheduling pass
1558 fmodulo-sched-allow-regmoves
1559 Common Report Var(flag_modulo_sched_allow_regmoves)
1560 Perform SMS based modulo scheduling with register moves allowed
1562 fmove-loop-invariants
1563 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1564 Move loop invariant computations out of loops
1567 Common Var(flag_dce) Init(1) Optimization
1568 Use the RTL dead code elimination pass
1571 Common Var(flag_dse) Init(1) Optimization
1572 Use the RTL dead store elimination pass
1574 freschedule-modulo-scheduled-loops
1575 Common Report Var(flag_resched_modulo_sched) Optimization
1576 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1578 fnon-call-exceptions
1579 Common Report Var(flag_non_call_exceptions) Optimization
1580 Support synchronous non-call exceptions
1583 Common Report Var(flag_omit_frame_pointer) Optimization
1584 When possible do not generate stack frames
1587 Common Report Var(flag_opt_info) Optimization
1588 Enable all optimization info dumps on stderr
1591 Common Joined RejectNegative Var(common_deferred_options) Defer
1592 -fopt-info[-<type>=filename] Dump compiler optimization details
1594 foptimize-register-move
1596 Does nothing. Preserved for backward compatibility.
1598 foptimize-sibling-calls
1599 Common Report Var(flag_optimize_sibling_calls) Optimization
1600 Optimize sibling and tail recursive calls
1603 Common Report Var(flag_partial_inlining)
1604 Perform partial inlining
1607 Common Report Var(pre_ipa_mem_report)
1608 Report on memory allocation before interprocedural optimization
1610 fpost-ipa-mem-report
1611 Common Report Var(post_ipa_mem_report)
1612 Report on memory allocation before interprocedural optimization
1615 Common Report Var(flag_pack_struct) Optimization
1616 Pack structure members together without holes
1619 Common RejectNegative Joined UInteger Optimization
1620 -fpack-struct=<number> Set initial maximum structure member alignment
1623 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1624 Return small aggregates in memory, not registers
1627 Common Report Var(flag_peel_loops) Optimization
1628 Perform loop peeling
1631 Common Report Var(flag_no_peephole,0) Optimization
1632 Enable machine specific peephole optimizations
1635 Common Report Var(flag_peephole2) Optimization
1636 Enable an RTL peephole pass before sched2
1639 Common Report Var(flag_pic,2) Negative(fPIE)
1640 Generate position-independent code if possible (large mode)
1643 Common Report Var(flag_pie,2) Negative(fpic)
1644 Generate position-independent code for executables if possible (large mode)
1647 Common Report Var(flag_pic,1) Negative(fpie)
1648 Generate position-independent code if possible (small mode)
1651 Common Report Var(flag_pie,1) Negative(fPIC)
1652 Generate position-independent code for executables if possible (small mode)
1655 Common Joined RejectNegative Var(common_deferred_options) Defer
1656 Specify a plugin to load
1659 Common Joined RejectNegative Var(common_deferred_options) Defer
1660 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1662 fpredictive-commoning
1663 Common Report Var(flag_predictive_commoning) Optimization
1664 Run predictive commoning optimization.
1666 fprefetch-loop-arrays
1667 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1668 Generate prefetch instructions, if available, for arrays in loops
1671 Common Report Var(profile_flag)
1672 Enable basic program profiling code
1675 Common Report Var(profile_arc_flag)
1676 Insert arc-based program profiling code
1679 Common Joined RejectNegative Var(profile_data_prefix)
1680 Set the top-level directory for storing the profile data.
1681 The default is 'pwd'.
1684 Common Report Var(flag_profile_correction)
1685 Enable correction of flow inconsistent profile data input
1689 Enable common options for generating profile info for profile feedback directed optimizations
1692 Common Joined RejectNegative
1693 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1696 Common Var(flag_profile_use)
1697 Enable common options for performing profile feedback directed optimizations
1700 Common Joined RejectNegative
1701 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1704 Common Report Var(flag_profile_values)
1705 Insert code to profile values of expressions
1708 Common Report Var(profile_report)
1709 Report on consistency of profile
1712 Common Var(common_deferred_options) Defer
1715 Common Joined RejectNegative Var(common_deferred_options) Defer
1716 -frandom-seed=<string> Make compile reproducible using <string>
1718 ; This switch causes the command line that was used to create an
1719 ; object file to be recorded into the object file. The exact format
1720 ; of this recording is target and binary file format dependent.
1721 ; It is related to the -fverbose-asm switch, but that switch only
1722 ; records information in the assembler output file as comments, so
1723 ; they never reach the object file.
1724 frecord-gcc-switches
1725 Common Report Var(flag_record_gcc_switches)
1726 Record gcc command line switches in the object file.
1729 Common Report Var(flag_pcc_struct_return,0) Optimization
1730 Return small aggregates in registers
1734 Does nothing. Preserved for backward compatibility.
1736 flive-range-shrinkage
1737 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
1738 Relief of register pressure through live range shrinkage
1741 Common Report Var(flag_rename_registers) Init(2) Optimization
1742 Perform a register renaming optimization pass
1745 Common Report Var(flag_reorder_blocks) Optimization
1746 Reorder basic blocks to improve code placement
1748 freorder-blocks-and-partition
1749 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1750 Reorder basic blocks and partition into hot and cold sections
1753 Common Report Var(flag_reorder_functions) Optimization
1754 Reorder functions to improve code placement
1756 frerun-cse-after-loop
1757 Common Report Var(flag_rerun_cse_after_loop) Optimization
1758 Add a common subexpression elimination pass after loop optimizations
1762 Does nothing. Preserved for backward compatibility.
1765 Common Report Var(flag_rounding_math) Optimization SetByCombined
1766 Disable optimizations that assume default FP rounding behavior
1769 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1770 Enable scheduling across basic blocks
1773 Common Report Var(flag_sched_pressure) Init(0) Optimization
1774 Enable register pressure sensitive insn scheduling
1777 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1778 Allow speculative motion of non-loads
1781 Common Report Var(flag_schedule_speculative_load) Optimization
1782 Allow speculative motion of some loads
1784 fsched-spec-load-dangerous
1785 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1786 Allow speculative motion of more loads
1789 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1790 -fsched-verbose=<number> Set the verbosity level of the scheduler
1792 fsched2-use-superblocks
1793 Common Report Var(flag_sched2_use_superblocks) Optimization
1794 If scheduling post reload, do superblock scheduling
1798 Does nothing. Preserved for backward compatibility.
1801 Common Report Var(flag_schedule_insns) Optimization
1802 Reschedule instructions before register allocation
1805 Common Report Var(flag_schedule_insns_after_reload) Optimization
1806 Reschedule instructions after register allocation
1808 ; This flag should be on when a target implements non-trivial
1809 ; scheduling hooks, maybe saving some information for its own sake.
1810 ; On IA64, for example, this is used for correct bundling.
1811 fselective-scheduling
1812 Common Report Var(flag_selective_scheduling) Optimization
1813 Schedule instructions using selective scheduling algorithm
1815 fselective-scheduling2
1816 Common Report Var(flag_selective_scheduling2) Optimization
1817 Run selective scheduling after reload
1819 fsel-sched-pipelining
1820 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1821 Perform software pipelining of inner loops during selective scheduling
1823 fsel-sched-pipelining-outer-loops
1824 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1825 Perform software pipelining of outer loops during selective scheduling
1827 fsel-sched-reschedule-pipelined
1828 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1829 Reschedule pipelined regions without pipelining
1831 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1832 ; of stalled insns into the ready list.
1833 fsched-stalled-insns
1834 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1835 Allow premature scheduling of queued insns
1837 fsched-stalled-insns=
1838 Common RejectNegative Joined UInteger
1839 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1841 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1842 ; be examined for a dependency on a stalled insn that is candidate for
1843 ; premature removal from the queue of stalled insns into the ready list (has
1844 ; an effect only if the flag 'sched_stalled_insns' is set).
1845 fsched-stalled-insns-dep
1846 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1847 Set dependence distance checking in premature scheduling of queued insns
1849 fsched-stalled-insns-dep=
1850 Common RejectNegative Joined UInteger
1851 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1853 fsched-group-heuristic
1854 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1855 Enable the group heuristic in the scheduler
1857 fsched-critical-path-heuristic
1858 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1859 Enable the critical path heuristic in the scheduler
1861 fsched-spec-insn-heuristic
1862 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1863 Enable the speculative instruction heuristic in the scheduler
1865 fsched-rank-heuristic
1866 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1867 Enable the rank heuristic in the scheduler
1869 fsched-last-insn-heuristic
1870 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1871 Enable the last instruction heuristic in the scheduler
1873 fsched-dep-count-heuristic
1874 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1875 Enable the dependent count heuristic in the scheduler
1878 Common Report Var(flag_section_anchors) Optimization
1879 Access data in the same section from shared anchor points
1883 Does nothing. Preserved for backward compatibility.
1887 Does nothing. Preserved for backward compatibility.
1890 Common Report Var(flag_ree) Init(0)
1891 Turn on Redundant Extensions Elimination pass.
1894 Common Report Var(flag_show_column) Init(1)
1895 Show column numbers in diagnostics, when available. Default on
1898 Common Report Var(flag_shrink_wrap) Optimization
1899 Emit function prologues only before parts of the function that need it,
1900 rather than at the top of the function.
1903 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1904 Disable optimizations observable by IEEE signaling NaNs
1907 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1908 Disable floating point optimizations that ignore the IEEE signedness of zero
1910 fsingle-precision-constant
1911 Common Report Var(flag_single_precision_constant) Optimization
1912 Convert floating point constants to single precision constants
1914 fsplit-ivs-in-unroller
1915 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1916 Split lifetimes of induction variables when loops are unrolled
1919 Common Report Var(flag_split_stack) Init(-1)
1920 Generate discontiguous stack frames
1923 Common Report Var(flag_split_wide_types) Optimization
1924 Split wide types into independent registers
1926 fvariable-expansion-in-unroller
1927 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1928 Apply variable expansion when loops are unrolled
1931 Common Report RejectNegative Joined
1932 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1935 Common Alias(fstack-check=, specific, no)
1936 Insert stack checking code into the program. Same as -fstack-check=specific
1939 Common Var(common_deferred_options) Defer
1941 fstack-limit-register=
1942 Common RejectNegative Joined Var(common_deferred_options) Defer
1943 -fstack-limit-register=<register> Trap if the stack goes past <register>
1945 fstack-limit-symbol=
1946 Common RejectNegative Joined Var(common_deferred_options) Defer
1947 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1950 Common Report Var(flag_stack_protect, 1)
1951 Use propolice as a stack protection method
1953 fstack-protector-all
1954 Common Report RejectNegative Var(flag_stack_protect, 2)
1955 Use a stack protection method for every function
1957 fstack-protector-strong
1958 Common Report RejectNegative Var(flag_stack_protect, 3)
1959 Use a smart stack protection method for certain functions
1962 Common RejectNegative Var(flag_stack_usage)
1963 Output stack usage information on a per-function basis
1967 Does nothing. Preserved for backward compatibility.
1969 ; Nonzero if we should do (language-dependent) alias analysis.
1970 ; Typically, this analysis will assume that expressions of certain
1971 ; types do not alias expressions of certain other types. Only used
1972 ; if alias analysis (in general) is enabled.
1974 Common Report Var(flag_strict_aliasing) Optimization
1975 Assume strict aliasing rules apply
1978 Common Report Var(flag_strict_overflow)
1979 Treat signed overflow as undefined
1982 Common Report Var(flag_sync_libcalls) Init(1)
1983 Implement __atomic operations via libcalls to legacy __sync functions
1986 Common Report Var(flag_syntax_only)
1987 Check for syntax errors, then stop
1990 Common Report Var(flag_test_coverage)
1991 Create data files needed by \"gcov\"
1994 Common Report Var(flag_thread_jumps) Optimization
1995 Perform jump threading optimizations
1998 Common Report Var(time_report)
1999 Report the time taken by each compiler pass
2002 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2003 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
2006 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2009 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2012 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2015 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2018 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2021 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
2022 Reorder top level functions, variables, and asms
2025 Common Report Var(flag_tracer)
2026 Perform superblock formation via tail duplication
2028 ; Zero means that floating-point math operations cannot generate a
2029 ; (user-visible) trap. This is the case, for example, in nonstop
2030 ; IEEE 754 arithmetic.
2032 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2033 Assume floating-point operations can trap
2036 Common Report Var(flag_trapv) Optimization
2037 Trap for signed overflow in addition, subtraction and multiplication
2040 Common Report Var(flag_tree_ccp) Optimization
2041 Enable SSA-CCP optimization on trees
2044 Common Report Var(flag_tree_bit_ccp) Optimization
2045 Enable SSA-BIT-CCP optimization on trees
2049 Does nothing. Preserved for backward compatibility.
2052 Common Report Var(flag_tree_ch) Optimization
2053 Enable loop header copying on trees
2055 ftree-coalesce-inlined-vars
2056 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
2057 Enable coalescing of copy-related user variables that are inlined
2060 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
2061 Enable coalescing of all copy-related user variables
2064 Common Report Var(flag_tree_copyrename) Optimization
2065 Replace SSA temporaries with better names in copies
2068 Common Report Var(flag_tree_copy_prop) Optimization
2069 Enable copy propagation on trees
2071 ftree-store-copy-prop
2073 Does nothing. Preserved for backward compatibility.
2076 Common Report Var(flag_tree_cselim) Init(2) Optimization
2077 Transform condition stores into unconditional ones
2079 ftree-switch-conversion
2080 Common Report Var(flag_tree_switch_conversion) Optimization
2081 Perform conversions of switch initializations.
2084 Common Report Var(flag_tree_dce) Optimization
2085 Enable SSA dead code elimination optimization on trees
2087 ftree-dominator-opts
2088 Common Report Var(flag_tree_dom) Optimization
2089 Enable dominator optimizations
2092 Common Report Var(flag_tree_tail_merge) Optimization
2093 Enable tail merging on trees
2096 Common Report Var(flag_tree_dse) Optimization
2097 Enable dead store elimination
2100 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2101 Enable forward propagation on trees
2104 Common Report Var(flag_tree_fre) Optimization
2105 Enable Full Redundancy Elimination (FRE) on trees
2108 Common Report Var(flag_optimize_strlen) Optimization
2109 Enable string length optimizations on trees
2111 fisolate-erroneous-paths
2112 Common Report Var(flag_isolate_erroneous_paths) Optimization
2113 Detect paths which trigger erroneous or undefined behaviour. Isolate those
2114 paths from the main control flow and turn the statement with erroneous or
2115 undefined behaviour into a trap.
2117 ftree-loop-distribution
2118 Common Report Var(flag_tree_loop_distribution) Optimization
2119 Enable loop distribution on trees
2121 ftree-loop-distribute-patterns
2122 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2123 Enable loop distribution for patterns transformed into a library call
2126 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2127 Enable loop invariant motion on trees
2130 Common Alias(floop-interchange)
2131 Enable loop interchange transforms. Same as -floop-interchange
2134 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2135 Create canonical induction variables in loops
2138 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2139 Enable loop optimizations on tree level
2141 ftree-parallelize-loops=
2142 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2143 Enable automatic parallelization of loops
2146 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2147 Enable hoisting loads from conditional pointers.
2150 Common Report Var(flag_tree_pre) Optimization
2151 Enable SSA-PRE optimization on trees
2154 Common Report Var(flag_tree_partial_pre) Optimization
2155 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2158 Common Report Var(flag_tree_pta) Init(1) Optimization
2159 Perform function-local points-to analysis on trees.
2162 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2163 Enable reassociation on tree level
2167 Does nothing. Preserved for backward compatibility.
2170 Common Report Var(flag_tree_sink) Optimization
2171 Enable SSA code sinking on trees
2174 Common Report Var(flag_tree_slsr) Optimization
2175 Perform straight-line strength reduction
2178 Common Report Var(flag_tree_sra) Optimization
2179 Perform scalar replacement of aggregates
2182 Common Report Var(flag_tree_ter) Optimization
2183 Replace temporary expressions in the SSA->normal pass
2186 Common Report Var(flag_tree_live_range_split) Optimization
2187 Perform live range splitting during the SSA->normal pass
2190 Common Report Var(flag_tree_vrp) Init(0) Optimization
2191 Perform Value Range Propagation on trees
2194 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2195 Compile whole compilation unit at a time
2198 Common Report Var(flag_unroll_loops) Optimization
2199 Perform loop unrolling when iteration count is known
2202 Common Report Var(flag_unroll_all_loops) Optimization
2203 Perform loop unrolling for all loops
2205 ; Nonzero means that loop optimizer may assume that the induction variables
2206 ; that control loops do not overflow and that the loops with nontrivial
2207 ; exit condition are not infinite
2208 funsafe-loop-optimizations
2209 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2210 Allow loop optimizations to assume that the loops behave in normal way
2213 Common Report Var(flag_associative_math) SetByCombined
2214 Allow optimization for floating-point arithmetic which may change the
2215 result of the operation due to rounding.
2218 Common Report Var(flag_reciprocal_math) SetByCombined
2219 Same as -fassociative-math for expressions which include division.
2221 ; Nonzero means that unsafe floating-point math optimizations are allowed
2222 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2223 ; are allowed to assume that their arguments and results are "normal"
2224 ; (e.g., nonnegative for SQRT).
2225 funsafe-math-optimizations
2226 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2227 Allow math optimizations that may violate IEEE or ISO standards
2230 Common Report Var(flag_unswitch_loops) Optimization
2231 Perform loop unswitching
2234 Common Report Var(flag_unwind_tables) Optimization
2235 Just generate unwind tables for exception handling
2238 Common Negative(fuse-ld=gold)
2239 Use the bfd linker instead of the default linker
2242 Common Negative(fuse-ld=bfd)
2243 Use the gold linker instead of the default linker
2248 ; Positive if we should track variables, negative if we should run
2249 ; the var-tracking pass only to discard debug annotations, zero if
2250 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2251 ; will be set according to optimize, debug_info_level and debug_hooks
2252 ; in process_options ().
2254 Common Report Var(flag_var_tracking) Init(2) Optimization
2255 Perform variable tracking
2257 ; Positive if we should track variables at assignments, negative if
2258 ; we should run the var-tracking pass only to discard debug
2259 ; annotations. When flag_var_tracking_assignments ==
2260 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2261 fvar-tracking-assignments
2262 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2263 Perform variable tracking by annotating assignments
2265 ; Nonzero if we should toggle flag_var_tracking_assignments after
2266 ; processing options and computing its default. */
2267 fvar-tracking-assignments-toggle
2268 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2269 Toggle -fvar-tracking-assignments
2271 ; Positive if we should track uninitialized variables, negative if
2272 ; we should run the var-tracking pass only to discard debug
2273 ; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
2274 ; will be set according to flag_var_tracking.
2275 fvar-tracking-uninit
2276 Common Report Var(flag_var_tracking_uninit) Optimization
2277 Perform variable tracking and also tag variables that are uninitialized
2280 Common Report Var(flag_tree_vectorize) Optimization
2281 Enable vectorization on trees
2283 ftree-vectorizer-verbose=
2284 Common Joined RejectNegative Ignore
2285 Does nothing. Preserved for backward compatibility.
2287 ftree-loop-vectorize
2288 Common Report Var(flag_tree_loop_vectorize) Optimization
2289 Enable loop vectorization on trees
2292 Common Report Var(flag_tree_slp_vectorize) Optimization
2293 Enable basic block vectorization (SLP) on trees
2296 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT)
2297 Specifies the cost model for vectorization
2300 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2303 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2306 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2309 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2312 Common RejectNegative Alias(fvect-cost-model=,dynamic)
2313 Enables the dynamic vectorizer cost model. Preserved for backward compatibility.
2316 Common RejectNegative Alias(fvect-cost-model=,unlimited)
2317 Enables the unlimited vectorizer cost model. Preserved for backward compatibility.
2319 ftree-vect-loop-version
2321 Does nothing. Preserved for backward compatibility.
2324 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2325 Enable copy propagation of scalar-evolution information.
2327 ; -fverbose-asm causes extra commentary information to be produced in
2328 ; the generated assembly code (to make it more readable). This option
2329 ; is generally only of use to those who actually need to read the
2330 ; generated assembly code (perhaps while debugging the compiler itself).
2331 ; -fno-verbose-asm, the default, causes the extra information
2332 ; to not be added and is useful when comparing two assembler files.
2334 Common Report Var(flag_verbose_asm)
2335 Add extra commentary to assembler output
2338 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2339 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2342 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2345 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2348 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2351 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2354 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2357 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2358 Validate vtable pointers before using them.
2361 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2364 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2367 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2370 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2373 Common Var(flag_vtv_counts)
2374 Output vtable verification counters.
2377 Common Var(flag_vtv_debug)
2378 Output vtable verification pointer sets information.
2381 Common Report Var(flag_value_profile_transformations) Optimization
2382 Use expression value profiles in optimizations
2385 Common Report Var(flag_web) Init(2) Optimization
2386 Construct webs and split unrelated uses of single variable
2388 ftree-builtin-call-dce
2389 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2390 Enable conditional dead code elimination for builtin calls
2393 Common Report Var(flag_whole_program) Init(0) Optimization
2394 Perform whole program optimizations
2397 Common Report Var(flag_wrapv) Optimization
2398 Assume signed arithmetic overflow wraps around
2400 fzero-initialized-in-bss
2401 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2402 Put zero initialized data in the bss section
2405 Common JoinedOrMissing
2406 Generate debug information in default format
2409 Common JoinedOrMissing Negative(gdwarf)
2410 Generate debug information in COFF format
2413 Common JoinedOrMissing Negative(gdwarf-)
2414 Generate debug information in default version of DWARF format
2417 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2418 Generate debug information in DWARF v2 (or later) format
2421 Common JoinedOrMissing
2422 Generate debug information in default extended format
2425 Common Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
2426 Don't generate DWARF pubnames and pubtypes sections.
2429 Common Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
2430 Generate DWARF pubnames and pubtypes sections.
2433 Common Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
2434 Generate DWARF pubnames and pubtypes sections with GNU extensions.
2436 gno-record-gcc-switches
2437 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2438 Don't record gcc command line switches in DWARF DW_AT_producer.
2440 grecord-gcc-switches
2441 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2442 Record gcc command line switches in DWARF DW_AT_producer.
2445 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2446 Don't generate debug information in separate .dwo files
2449 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2450 Generate debug information in separate .dwo files
2453 Common JoinedOrMissing Negative(gstabs+)
2454 Generate debug information in STABS format
2457 Common JoinedOrMissing Negative(gvms)
2458 Generate debug information in extended STABS format
2461 Common RejectNegative Var(dwarf_strict,0) Init(0)
2462 Emit DWARF additions beyond selected version
2465 Common Report RejectNegative Var(dwarf_strict,1)
2466 Don't emit DWARF additions beyond selected version
2469 Common Report Var(flag_gtoggle)
2470 Toggle debug information generation
2473 Common JoinedOrMissing Negative(gxcoff)
2474 Generate debug information in VMS format
2477 Common JoinedOrMissing Negative(gxcoff+)
2478 Generate debug information in XCOFF format
2481 Common JoinedOrMissing Negative(gcoff)
2482 Generate debug information in extended XCOFF format
2485 Driver Joined Separate
2488 Common Joined Var(plugindir_string) Init(0)
2489 -iplugindir=<dir> Set <dir> to be the default plugin directory
2492 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2493 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory
2496 Driver Joined Separate
2501 no-canonical-prefixes
2514 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2515 -o <file> Place output into <file>
2518 Common Var(profile_flag)
2519 Enable function profiling
2522 Driver Var(pass_exit_codes)
2525 Common Alias(Wpedantic)
2528 Common Var(flag_pedantic_errors)
2529 Like -pedantic but issue them as errors
2535 Driver Var(use_pipes)
2538 Driver JoinedOrMissing Var(print_file_name)
2540 print-libgcc-file-name
2543 print-multi-directory
2544 Driver Var(print_multi_directory)
2547 Driver Var(print_multi_lib)
2549 print-multi-os-directory
2550 Driver Var(print_multi_os_directory)
2553 Driver Var(print_multiarch)
2556 Driver JoinedOrMissing Var(print_prog_name)
2559 Driver Var(print_search_dirs)
2562 Driver Var(print_sysroot)
2564 print-sysroot-headers-suffix
2565 Driver Var(print_sysroot_headers_suffix)
2568 Common Var(quiet_flag) RejectDriver
2569 Do not display functions compiled or elapsed time
2587 Driver Var(report_times)
2590 Driver JoinedOrMissing
2593 Driver Joined Separate
2597 ; C option, but driver must not handle as "-u ndef".
2600 Common Driver Var(verbose_flag)
2601 Enable verbose output
2604 Common Var(version_flag) RejectDriver
2605 Display the compiler's version
2608 Common Var(inhibit_warnings)
2612 Driver Separate Var(wrapper_string)
2615 Driver Joined Separate
2618 Driver RejectNegative Negative(pie)
2619 Create a shared library
2625 Driver Separate Alias(specs=)
2638 ; Documented for Fortran, but always accepted by driver.
2645 ; Documented for Go, but always accepted by driver.
2660 Driver RejectNegative Negative(shared)
2661 Create a position independent executable
2664 Driver Joined Separate
2666 ; This comment is to ensure we retain the blank line above.