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
220 Driver Alias(coverage)
226 Common Separate Alias(d)
229 Common Joined Alias(d)
232 Common Separate Alias(dumpbase)
235 Common Separate Alias(dumpdir)
238 Driver Separate Alias(e)
241 Driver Joined Alias(e)
244 Common Warning Alias(Wextra)
247 Driver Separate Alias(Xassembler)
250 Driver JoinedOrMissing Alias(Xassembler)
253 Driver Separate Alias(Xlinker)
256 Driver JoinedOrMissing Alias(Xlinker)
259 Driver Separate Alias(u)
262 Driver Joined Alias(u)
265 Common Driver Var(help_flag)
266 Display this information
269 Common Driver Report Joined
270 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
273 Driver Separate Alias(x)
276 Driver Joined Alias(x)
279 Driver Separate Alias(L)
282 Driver Joined Alias(L)
284 -no-canonical-prefixes
285 Driver Alias(no-canonical-prefixes)
287 -no-standard-libraries
288 Driver Alias(nostdlib)
291 Driver Var(no_sysroot_suffix)
300 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
303 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
306 Driver Alias(pass-exit-codes)
309 Common Alias(Wpedantic)
312 Common Alias(pedantic-errors)
321 Driver Separate Alias(B)
324 Driver JoinedOrMissing Alias(B)
330 Driver Separate Alias(print-file-name=)
333 Driver JoinedOrMissing Alias(print-file-name=)
335 -print-libgcc-file-name
336 Driver Alias(print-libgcc-file-name)
338 -print-multi-directory
339 Driver Alias(print-multi-directory)
342 Driver Alias(print-multi-lib)
344 -print-multi-os-directory
345 Driver Alias(print-multi-os-directory)
348 Driver Alias(print-multiarch)
351 Driver Separate Alias(print-prog-name=)
354 Driver JoinedOrMissing Alias(print-prog-name=)
357 Driver Alias(print-search-dirs)
360 Driver Alias(print-sysroot)
362 -print-sysroot-headers-suffix
363 Driver Alias(print-sysroot-headers-suffix)
369 Driver Alias(save-temps)
375 Driver Separate Alias(specs=)
378 Driver Joined Alias(specs=)
384 Driver Alias(symbolic)
388 Alias for --help=target
396 ;; The driver used to convert options such as --help into forms such
397 ;; as -fhelp; the following four entries are for compatibility with
398 ;; any direct uses of those (undocumented) -f forms
400 Common Driver Alias(-help)
403 Common Driver Joined Alias(-help=)
406 Common Driver Alias(-target-help)
409 Common Driver Alias(-version)
413 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
416 Common Joined Alias(-param)
419 Driver Separate Alias(-sysroot=)
422 Driver JoinedOrMissing
428 Driver Joined Separate
434 Driver Joined Separate
440 Common JoinedOrMissing Optimization
441 -O<number> Set optimization level to <number>
445 Optimize for space rather than speed
449 Optimize for speed disregarding exact standards compliance
453 Optimize for debugging experience rather than speed or size
465 Driver Joined Separate
471 Driver Joined Separate
492 Common RejectNegative Warning Alias(Wextra)
493 This switch is deprecated; use -Wextra instead
496 Driver JoinedOrMissing
499 Driver JoinedOrMissing
502 Driver JoinedOrMissing
505 Common Var(warn_aggregate_return) Warning
506 Warn about returning structures, unions or arrays
509 Common Var(warn_array_bounds) Warning
510 Warn if an array is accessed out of bounds
513 Common Var(warn_attributes) Init(1) Warning
514 Warn about inappropriate attribute usage
517 Common Var(warn_cast_align) Warning
518 Warn about pointer casts which increase alignment
521 Common Var(warn_cpp) Init(1) Warning
522 Warn when a #warning directive is encountered
524 Wdeprecated-declarations
525 Common Var(warn_deprecated_decl) Init(1) Warning
526 Warn about uses of __attribute__((deprecated)) declarations
528 Wdisabled-optimization
529 Common Var(warn_disabled_optimization) Warning
530 Warn when an optimization pass is disabled
533 Common Var(warnings_are_errors)
534 Treat all warnings as errors
538 Treat specified warning as error
541 Common Var(extra_warnings) Warning
542 Print extra (possibly unwanted) warnings
545 Common Var(flag_fatal_errors)
546 Exit on the first error occurred
549 Common RejectNegative Joined UInteger
550 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
553 Common Var(warn_free_nonheap_object) Init(1) Warning
554 Warn when attempting to free a non-heap object
557 Common Var(warn_inline) Warning
558 Warn when an inlined function cannot be inlined
560 Winvalid-memory-model
561 Common Var(warn_invalid_memory_model) Init(1) Warning
562 Warn when an atomic memory model parameter is known to be outside the valid range.
565 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
568 Common RejectNegative Joined UInteger Warning
569 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
571 Wunsafe-loop-optimizations
572 Common Var(warn_unsafe_loop_optimizations) Warning
573 Warn if the loop cannot be optimized due to nontrivial assumptions.
576 Common Alias(Wsuggest-attribute=noreturn)
579 Common Var(warn_overflow) Init(1) Warning
580 Warn about overflow in arithmetic expressions
583 Common Var(warn_packed) Warning
584 Warn when the packed attribute has no effect on struct layout
587 Common Var(warn_padded) Warning
588 Warn when padding is required to align structure members
591 Common Var(pedantic) Warning
592 Issue warnings needed for strict compliance to the standard
595 Common Var(warn_shadow) Warning
596 Warn when one local variable shadows another
599 Common Var(warn_stack_protect) Warning
600 Warn when not issuing stack smashing protection for some reason
603 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
604 Warn if stack usage might be larger than specified amount
608 Warn about code which might break strict aliasing rules
611 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
612 Warn about code which might break strict aliasing rules
616 Warn about optimizations that assume that signed overflow is undefined
619 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
620 Warn about optimizations that assume that signed overflow is undefined
622 Wsuggest-attribute=const
623 Common Var(warn_suggest_attribute_const) Warning
624 Warn about functions which might be candidates for __attribute__((const))
626 Wsuggest-attribute=pure
627 Common Var(warn_suggest_attribute_pure) Warning
628 Warn about functions which might be candidates for __attribute__((pure))
630 Wsuggest-attribute=noreturn
631 Common Var(warn_suggest_attribute_noreturn) Warning
632 Warn about functions which might be candidates for __attribute__((noreturn))
635 Common Var(warn_system_headers) Warning
636 Do not suppress warnings from system headers
639 Common Var(warn_trampolines) Warning
640 Warn whenever a trampoline is generated
643 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
644 Warn if a comparison is always true or always false due to the limited range of the data type
647 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
648 Warn about uninitialized automatic variables
651 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
652 Warn about maybe uninitialized automatic variables
656 Does nothing. Preserved for backward compatibility.
659 Common Var(warn_unused) Init(0) Warning
660 Enable all -Wunused- warnings
662 Wunused-but-set-parameter
663 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
664 Warn when a function parameter is only set, otherwise unused
666 Wunused-but-set-variable
667 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
668 Warn when a variable is only set, otherwise unused
671 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
672 Warn when a function is unused
675 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
676 Warn when a label is unused
679 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
680 Warn when a function parameter is unused
683 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
684 Warn when an expression value is unused
687 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
688 Warn when a variable is unused
691 Common Var(warn_coverage_mismatch) Init(1) Warning
692 Warn in case profiles in -fprofile-use do not match
694 Wvector-operation-performance
695 Common Var(warn_vector_operation_performance) Warning
696 Warn when a vector operation is compiled outside the SIMD
711 Common Separate Var(aux_info_file_name)
712 -aux-info <file> Emit declaration information into <file>
715 Common Joined Alias(aux-info)
718 Common Separate RejectDriver Var(aux_base_name)
721 Common Separate RejectDriver
731 -d<letters> Enable dumps from specific passes of the compiler
734 Common Separate Var(dump_base_name)
735 -dumpbase <file> Set the file basename to be used for dumps
738 Common Separate Var(dump_dir_name)
739 -dumpdir <dir> Set the directory name to be used for dumps
751 Driver Joined Separate
753 ; This option has historically been passed down to the linker by an
754 ; accident of a %{e*} spec, so ensure it continues to be passed down
755 ; as a single option. The supported option for this purpose is
756 ; -rdynamic. See PR 47390.
760 ; The version of the C++ ABI in use. The following values are allowed:
762 ; 0: The version of the ABI believed most conformant with the C++ ABI
763 ; specification. This ABI may change as bugs are discovered and fixed.
764 ; Therefore, 0 will not necessarily indicate the same ABI in different
767 ; 1: The version of the ABI first used in G++ 3.2.
769 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
771 ; 3: The version of the ABI that fixes the missing underscore
772 ; in template non-type arguments of pointer type.
774 ; 4: The version of the ABI that introduces unambiguous mangling of
775 ; vector types. First selectable in G++ 4.5.
777 ; 5: The version of the ABI that ignores attribute const/noreturn
778 ; in function pointer mangling, and corrects mangling of decltype and
779 ; function parameters used in other parameters and the return type.
780 ; First selectable in G++ 4.6.
782 ; 6: The version of the ABI that doesn't promote scoped enums to int and
783 ; changes the mangling of template argument packs, const/static_cast,
784 ; prefix ++ and --, and a class scope function used as a template
786 ; First selectable in G++ 4.7.
788 ; 7: The version of the ABI that treats nullptr_t as a builtin type.
789 ; First selectable in G++ 4.8.
790 ; Additional positive integers will be assigned as new versions of
791 ; the ABI become the default version of the ABI.
793 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
795 faggressive-loop-optimizations
796 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
797 Aggressively optimize loops using language constraints
800 Common Report Var(align_functions,0) Optimization UInteger
801 Align the start of functions
804 Common RejectNegative Joined UInteger Var(align_functions)
807 Common Report Var(align_jumps,0) Optimization UInteger
808 Align labels which are only reached by jumping
811 Common RejectNegative Joined UInteger Var(align_jumps)
814 Common Report Var(align_labels,0) Optimization UInteger
818 Common RejectNegative Joined UInteger Var(align_labels)
821 Common Report Var(align_loops,0) Optimization UInteger
822 Align the start of loops
825 Common RejectNegative Joined UInteger Var(align_loops)
829 Does nothing. Preserved for backward compatibility.
833 Does nothing. Preserved for backward compatibility.
835 fargument-noalias-global
837 Does nothing. Preserved for backward compatibility.
839 fargument-noalias-anything
841 Does nothing. Preserved for backward compatibility.
844 Common Report Var(flag_asan)
845 Enable AddressSanitizer, a memory error detector
848 Common Report Var(flag_tsan)
849 Enable ThreadSanitizer, a data race detector
851 fasynchronous-unwind-tables
852 Common Report Var(flag_asynchronous_unwind_tables) Optimization
853 Generate unwind tables that are exact at each instruction boundary
856 Common Report Var(flag_auto_inc_dec) Init(1)
857 Generate auto-inc/dec instructions
859 ; -fcheck-bounds causes gcc to generate array bounds checks.
860 ; For C, C++ and ObjC: defaults off.
861 ; For Java: defaults to on.
862 ; For Fortran: defaults to off.
864 Common Report Var(flag_bounds_check)
865 Generate code to check bounds before indexing arrays
868 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
869 Replace add, compare, branch with branch on count register
871 fbranch-probabilities
872 Common Report Var(flag_branch_probabilities) Optimization
873 Use profiling information for branch probabilities
875 fbranch-target-load-optimize
876 Common Report Var(flag_branch_target_load_optimize) Optimization
877 Perform branch target load optimization before prologue / epilogue threading
879 fbranch-target-load-optimize2
880 Common Report Var(flag_branch_target_load_optimize2) Optimization
881 Perform branch target load optimization after prologue / epilogue threading
884 Common Report Var(flag_btr_bb_exclusive) Optimization
885 Restrict target load migration not to re-use registers in any basic block
888 Common Joined RejectNegative Var(common_deferred_options) Defer
889 -fcall-saved-<register> Mark <register> as being preserved across functions
892 Common Joined RejectNegative Var(common_deferred_options) Defer
893 -fcall-used-<register> Mark <register> as being corrupted by function calls
895 ; Nonzero for -fcaller-saves: allocate values in regs that need to
896 ; be saved across function calls, if that produces overall better code.
897 ; Optional now, so people can test it.
899 Common Report Var(flag_caller_saves) Optimization
900 Save registers around function calls
903 Common Report Var(flag_check_data_deps)
904 Compare the results of several data dependence analyzers.
906 fcombine-stack-adjustments
907 Common Report Var(flag_combine_stack_adjustments) Optimization
908 Looks for opportunities to reduce stack adjustments and stack references.
911 Common Report Var(flag_no_common,0) Optimization
912 Do not put uninitialized globals in the common section
916 ; Converted by the driver to -fcompare-debug= options.
919 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
920 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
922 fcompare-debug-second
923 Common Driver RejectNegative Var(flag_compare_debug)
924 Run only the second compilation of -fcompare-debug
927 Common Report Var(flag_compare_elim_after_reload) Optimization
928 Perform comparison elimination after register allocation has finished
931 Common Var(flag_conserve_stack) Optimization
932 Do not perform optimizations increasing noticeably stack usage
935 Common Report Var(flag_cprop_registers) Optimization
936 Perform a register copy-propagation optimization pass
939 Common Report Var(flag_crossjumping) Optimization
940 Perform cross-jumping optimization
943 Common Report Var(flag_cse_follow_jumps) Optimization
944 When running CSE, follow jumps to their targets
948 Does nothing. Preserved for backward compatibility.
951 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
952 Omit range reduction step when performing complex division
955 Common Report Var(flag_cx_fortran_rules) Optimization
956 Complex multiplication and division follow Fortran rules
959 Common Report Var(flag_data_sections) Optimization
960 Place data items into their own section
963 Common Report Var(common_deferred_options) Defer
964 List all available debugging counters with their limits and counts.
967 Common RejectNegative Joined Var(common_deferred_options) Defer
968 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
971 Common Joined RejectNegative Var(common_deferred_options) Defer
972 Map one directory name to another in debug information
975 Common Report Var(flag_debug_types_section) Init(0)
976 Output .debug_types section when using DWARF v4 debuginfo.
978 ; Nonzero for -fdefer-pop: don't pop args after each function call
979 ; instead save them up to pop many calls' args with one insns.
981 Common Report Var(flag_defer_pop) Optimization
982 Defer popping functions args from stack until later
985 Common Report Var(flag_delayed_branch) Optimization
986 Attempt to fill delay slots of branch instructions
988 fdelete-dead-exceptions
989 Common Report Var(flag_delete_dead_exceptions) Init(0)
990 Delete dead instructions that may throw exceptions
992 fdelete-null-pointer-checks
993 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
994 Delete useless null pointer checks
997 Common Report Var(flag_devirtualize) Optimization
998 Try to convert virtual calls to direct ones.
1000 fdiagnostics-show-location=
1001 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1002 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
1004 ; Required for these enum values.
1009 Name(diagnostic_prefixing_rule) Type(int)
1012 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1015 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1017 fdiagnostics-show-caret
1018 Common Var(flag_diagnostics_show_caret) Init(1)
1019 Show the source line with a caret indicating the column
1021 fdiagnostics-show-option
1022 Common Var(flag_diagnostics_show_option) Init(1)
1023 Amend appropriate diagnostic messages with the command line option that controls them
1026 Common Joined RejectNegative Var(common_deferred_options) Defer
1027 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1030 Common Joined RejectNegative Var(common_deferred_options) Defer
1031 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1034 Common Joined RejectNegative Var(common_deferred_options) Defer
1035 -fdump-<type> Dump various compiler internals to a file
1038 Driver RejectNegative
1041 Common RejectNegative Joined Var(flag_dump_final_insns)
1042 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1045 Common RejectNegative Joined Var(flag_dump_go_spec)
1046 -fdump-go-spec=filename Write all declarations to file as Go code
1049 Common Report Var(flag_dump_noaddr)
1050 Suppress output of addresses in debugging dumps
1053 Common Var(flag_dump_passes) Init(0)
1054 Dump optimization passes
1057 Common Report Var(flag_dump_unnumbered)
1058 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1060 fdump-unnumbered-links
1061 Common Report Var(flag_dump_unnumbered_links)
1062 Suppress output of previous and next insn numbers in debugging dumps
1065 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1066 Enable CFI tables via GAS assembler directives.
1069 Common Report Var(flag_early_inlining) Init(1) Optimization
1070 Perform early inlining
1072 feliminate-dwarf2-dups
1073 Common Report Var(flag_eliminate_dwarf2_dups)
1074 Perform DWARF2 duplicate elimination
1077 Common Report Var(flag_ipa_sra) Init(0) Optimization
1078 Perform interprocedural reduction of aggregates
1080 feliminate-unused-debug-symbols
1081 Common Report Var(flag_debug_only_used_symbols)
1082 Perform unused type elimination in debug info
1084 feliminate-unused-debug-types
1085 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1086 Perform unused type elimination in debug info
1088 femit-class-debug-always
1089 Common Report Var(flag_emit_class_debug_always) Init(0)
1090 Do not suppress C++ class debug information.
1093 Common Report Var(flag_exceptions) Optimization
1094 Enable exception handling
1096 fexpensive-optimizations
1097 Common Report Var(flag_expensive_optimizations) Optimization
1098 Perform a number of minor, expensive optimizations
1101 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1102 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1105 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1108 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1111 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1117 Common Var(flag_fat_lto_objects) Init(1)
1118 Output lto objects containing both the intermediate language and binary output.
1121 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1122 Assume no NaNs or infinities are generated
1125 Common Joined RejectNegative Var(common_deferred_options) Defer
1126 -ffixed-<register> Mark <register> as being unavailable to the compiler
1129 Common Report Var(flag_float_store) Optimization
1130 Don't allocate floats and doubles in extended-precision registers
1134 Does nothing. Preserved for backward compatibility.
1137 Common Report Var(flag_forward_propagate) Optimization
1138 Perform a forward propagation pass on RTL
1141 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1142 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1145 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1148 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1150 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1152 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1155 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1157 ; Nonzero means don't put addresses of constant functions in registers.
1158 ; Used for compiling the Unix kernel, where strange substitutions are
1159 ; done on the assembly output.
1161 Common Report Var(flag_no_function_cse,0)
1162 Allow function addresses to be held in registers
1165 Common Report Var(flag_function_sections)
1166 Place each function into its own section
1169 Common Report Var(flag_gcse) Optimization
1170 Perform global common subexpression elimination
1173 Common Report Var(flag_gcse_lm) Init(1) Optimization
1174 Perform enhanced load motion during global common subexpression elimination
1177 Common Report Var(flag_gcse_sm) Init(0) Optimization
1178 Perform store motion after global common subexpression elimination
1181 Common Report Var(flag_gcse_las) Init(0) Optimization
1182 Perform redundant load after store elimination in global common subexpression
1186 Common Report Var(flag_gcse_after_reload) Optimization
1187 Perform global common subexpression elimination after register allocation
1190 ; This option is not documented yet as its semantics will change.
1192 Common Report Var(flag_graphite)
1193 Enable in and out of Graphite representation
1196 Common Report Var(flag_graphite_identity) Optimization
1197 Enable Graphite Identity transformation
1199 fhoist-adjacent-loads
1200 Common Report Var(flag_hoist_adjacent_loads) Optimization
1201 Enable hoisting adjacent loads to encourage generating conditional move
1204 floop-parallelize-all
1205 Common Report Var(flag_loop_parallelize_all) Optimization
1206 Mark all loops as parallel
1209 Common Report Var(flag_loop_strip_mine) Optimization
1210 Enable Loop Strip Mining transformation
1213 Common Report Var(flag_loop_interchange) Optimization
1214 Enable Loop Interchange transformation
1217 Common Report Var(flag_loop_block) Optimization
1218 Enable Loop Blocking transformation
1221 Common Report Var(flag_tm)
1222 Enable support for GNU transactional memory
1226 Does nothing. Preserved for backward compatibility.
1229 Common Report Var(flag_loop_optimize_isl) Optimization
1230 Enable the ISL based loop nest optimizer
1232 fstrict-volatile-bitfields
1233 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1234 Force bitfield accesses to match their type width
1236 fguess-branch-probability
1237 Common Report Var(flag_guess_branch_prob) Optimization
1238 Enable guessing of branch probabilities
1240 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1241 ; Generate position-independent code for executables if possible
1242 ; On SVR4 targets, it also controls whether or not to emit a
1243 ; string identifying the compiler.
1245 Common Report Var(flag_no_ident,0)
1246 Process #ident directives
1249 Common Report Var(flag_if_conversion) Optimization
1250 Perform conversion of conditional jumps to branchless equivalents
1253 Common Report Var(flag_if_conversion2) Optimization
1254 Perform conversion of conditional jumps to conditional execution
1257 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL)
1258 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1261 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1264 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1267 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1270 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1272 ftree-loop-if-convert
1273 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1274 Convert conditional jumps in innermost loops to branchless equivalents
1276 ftree-loop-if-convert-stores
1277 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1278 Also if-convert conditional jumps containing memory writes
1280 ; -finhibit-size-directive inhibits output of .size for ELF.
1281 ; This is used only for compiling crtstuff.c,
1282 ; and it may be extended to other effects
1283 ; needed for crtstuff.c on other systems.
1284 finhibit-size-directive
1285 Common Report Var(flag_inhibit_size_directive)
1286 Do not generate .size directives
1289 Common Report Var(flag_indirect_inlining)
1290 Perform indirect inlining
1292 ; General flag to enable inlining. Specifying -fno-inline will disable
1293 ; all inlining apart from always-inline functions.
1295 Common Report Var(flag_no_inline,0) Init(0) Optimization
1296 Enable inlining of function declared \"inline\", disabling disables all inlining
1298 finline-small-functions
1299 Common Report Var(flag_inline_small_functions) Optimization
1300 Integrate functions into their callers when code size is known not to grow
1303 Common Report Var(flag_inline_functions) Optimization
1304 Integrate functions not declared \"inline\" into their callers when profitable
1306 finline-functions-called-once
1307 Common Report Var(flag_inline_functions_called_once) Optimization
1308 Integrate functions only required by their single caller
1311 Common RejectNegative Joined Alias(finline-limit=)
1314 Common RejectNegative Joined UInteger
1315 -finline-limit=<number> Limit the size of inlined functions to <number>
1318 Common Report Var(flag_inline_atomics) Init(1) Optimization
1319 Inline __atomic operations when a lock free instruction sequence is available.
1321 finstrument-functions
1322 Common Report Var(flag_instrument_function_entry_exit)
1323 Instrument function entry and exit with profiling calls
1325 finstrument-functions-exclude-function-list=
1326 Common RejectNegative Joined
1327 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1329 finstrument-functions-exclude-file-list=
1330 Common RejectNegative Joined
1331 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1334 Common Report Var(flag_ipa_cp) Optimization
1335 Perform Interprocedural constant propagation
1338 Common Report Var(flag_ipa_cp_clone) Optimization
1339 Perform cloning to make Interprocedural constant propagation stronger
1342 Common Report Var(flag_ipa_profile) Init(0) Optimization
1343 Perform interprocedural profile propagation
1346 Common Report Var(flag_ipa_pta) Init(0) Optimization
1347 Perform interprocedural points-to analysis
1350 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1351 Discover pure and const functions
1354 Common Report Var(flag_ipa_reference) Init(0) Optimization
1355 Discover readonly and non addressable static variables
1359 Does nothing. Preserved for backward compatibility.
1363 Does nothing. Preserved for backward compatibility.
1366 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1367 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1370 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1373 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1376 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1379 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1380 -fira-region=[one|all|mixed] Set regions for IRA
1383 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1386 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1389 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1392 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1395 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1396 Use IRA based register pressure calculation
1397 in RTL hoist optimizations.
1400 Common Report Var(flag_ira_loop_pressure)
1401 Use IRA based register pressure calculation
1402 in RTL loop optimizations.
1404 fira-share-save-slots
1405 Common Report Var(flag_ira_share_save_slots) Init(1)
1406 Share slots for saving different hard registers.
1408 fira-share-spill-slots
1409 Common Report Var(flag_ira_share_spill_slots) Init(1)
1410 Share stack slots for spilled pseudo-registers.
1413 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1414 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1417 Common Report Var(flag_ivopts) Init(1) Optimization
1418 Optimize induction variables on trees
1421 Common Var(flag_jump_tables) Init(1) Optimization
1422 Use jump tables for sufficiently large switch statements
1424 fkeep-inline-functions
1425 Common Report Var(flag_keep_inline_functions)
1426 Generate code for functions even if they are fully inlined
1429 Common Report Var(flag_keep_static_consts) Init(1)
1430 Emit static const variables even if they are not used
1433 Common Report Var(flag_leading_underscore) Init(-1)
1434 Give external symbols a leading underscore
1438 Does nothing. Preserved for backward compatibility.
1442 Enable link-time optimization.
1445 Common RejectNegative Joined Var(flag_lto)
1446 Link-time optimization with number of parallel jobs or jobserver.
1449 Common Var(flag_lto_partition_1to1)
1450 Partition symbols and vars at linktime based on object files they originate from
1452 flto-partition=balanced
1453 Common Var(flag_lto_partition_balanced)
1454 Partition functions and vars at linktime into approximately same sized buckets
1457 Common Var(flag_lto_partition_max)
1458 Put every symbol into separate partition
1461 Common Var(flag_lto_partition_none)
1462 Disable partioning and streaming
1464 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1465 flto-compression-level=
1466 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1467 -flto-compression-level=<number> Use zlib compression level <number> for IL
1470 Common Report Var(flag_lto_report) Init(0)
1471 Report various link-time optimization statistics
1474 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1475 Set errno after built-in math functions
1478 Common Joined RejectNegative UInteger Var(flag_max_errors)
1479 -fmax-errors=<number> Maximum number of errors to report
1482 Common Report Var(mem_report)
1483 Report on permanent memory allocation
1486 Common Report Var(mem_report_wpa)
1487 Report on permanent memory allocation in WPA only
1489 ; This will attempt to merge constant section constants, if 1 only
1490 ; string constants and constants from constant pool, if 2 also constant
1492 fmerge-all-constants
1493 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1494 Attempt to merge identical constants and constant variables
1497 Common Report Var(flag_merge_constants,1) Optimization
1498 Attempt to merge identical constants across compilation units
1500 fmerge-debug-strings
1501 Common Report Var(flag_merge_debug_strings) Init(1)
1502 Attempt to merge identical debug strings across compilation units
1505 Common RejectNegative Joined UInteger
1506 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1509 Common Report Var(flag_modulo_sched) Optimization
1510 Perform SMS based modulo scheduling before the first scheduling pass
1512 fmodulo-sched-allow-regmoves
1513 Common Report Var(flag_modulo_sched_allow_regmoves)
1514 Perform SMS based modulo scheduling with register moves allowed
1516 fmove-loop-invariants
1517 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1518 Move loop invariant computations out of loops
1521 Common Var(flag_dce) Init(1) Optimization
1522 Use the RTL dead code elimination pass
1525 Common Var(flag_dse) Init(1) Optimization
1526 Use the RTL dead store elimination pass
1528 freschedule-modulo-scheduled-loops
1529 Common Report Var(flag_resched_modulo_sched) Optimization
1530 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1532 fnon-call-exceptions
1533 Common Report Var(flag_non_call_exceptions) Optimization
1534 Support synchronous non-call exceptions
1537 Common Report Var(flag_omit_frame_pointer) Optimization
1538 When possible do not generate stack frames
1541 Common Report Var(flag_opt_info) Optimization
1542 Enable all optimization info dumps on stderr
1545 Common Joined RejectNegative Var(common_deferred_options) Defer
1546 -fopt-info[-<type>=filename] Dump compiler optimization details
1548 foptimize-register-move
1549 Common Report Var(flag_regmove) Optimization
1550 Do the full register move optimization pass
1552 foptimize-sibling-calls
1553 Common Report Var(flag_optimize_sibling_calls) Optimization
1554 Optimize sibling and tail recursive calls
1557 Common Report Var(flag_partial_inlining)
1558 Perform partial inlining
1561 Common Report Var(pre_ipa_mem_report)
1562 Report on memory allocation before interprocedural optimization
1564 fpost-ipa-mem-report
1565 Common Report Var(post_ipa_mem_report)
1566 Report on memory allocation before interprocedural optimization
1569 Common Report Var(flag_pack_struct) Optimization
1570 Pack structure members together without holes
1573 Common RejectNegative Joined UInteger Optimization
1574 -fpack-struct=<number> Set initial maximum structure member alignment
1577 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1578 Return small aggregates in memory, not registers
1581 Common Report Var(flag_peel_loops) Optimization
1582 Perform loop peeling
1585 Common Report Var(flag_no_peephole,0) Optimization
1586 Enable machine specific peephole optimizations
1589 Common Report Var(flag_peephole2) Optimization
1590 Enable an RTL peephole pass before sched2
1593 Common Report Var(flag_pic,2) Negative(fPIE)
1594 Generate position-independent code if possible (large mode)
1597 Common Report Var(flag_pie,2) Negative(fpic)
1598 Generate position-independent code for executables if possible (large mode)
1601 Common Report Var(flag_pic,1) Negative(fpie)
1602 Generate position-independent code if possible (small mode)
1605 Common Report Var(flag_pie,1) Negative(fPIC)
1606 Generate position-independent code for executables if possible (small mode)
1609 Common Joined RejectNegative Var(common_deferred_options) Defer
1610 Specify a plugin to load
1613 Common Joined RejectNegative Var(common_deferred_options) Defer
1614 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1616 fpredictive-commoning
1617 Common Report Var(flag_predictive_commoning) Optimization
1618 Run predictive commoning optimization.
1620 fprefetch-loop-arrays
1621 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1622 Generate prefetch instructions, if available, for arrays in loops
1625 Common Report Var(profile_flag)
1626 Enable basic program profiling code
1629 Common Report Var(profile_arc_flag)
1630 Insert arc-based program profiling code
1633 Common Joined RejectNegative Var(profile_data_prefix)
1634 Set the top-level directory for storing the profile data.
1635 The default is 'pwd'.
1638 Common Report Var(flag_profile_correction)
1639 Enable correction of flow inconsistent profile data input
1643 Enable common options for generating profile info for profile feedback directed optimizations
1646 Common Joined RejectNegative
1647 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1650 Common Var(flag_profile_use)
1651 Enable common options for performing profile feedback directed optimizations
1654 Common Joined RejectNegative
1655 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1658 Common Report Var(flag_profile_values)
1659 Insert code to profile values of expressions
1662 Common Report Var(profile_report)
1663 Report on consistency of profile
1666 Common Var(common_deferred_options) Defer
1669 Common Joined RejectNegative Var(common_deferred_options) Defer
1670 -frandom-seed=<string> Make compile reproducible using <string>
1672 ; This switch causes the command line that was used to create an
1673 ; object file to be recorded into the object file. The exact format
1674 ; of this recording is target and binary file format dependent.
1675 ; It is related to the -fverbose-asm switch, but that switch only
1676 ; records information in the assembler output file as comments, so
1677 ; they never reach the object file.
1678 frecord-gcc-switches
1679 Common Report Var(flag_record_gcc_switches)
1680 Record gcc command line switches in the object file.
1683 Common Report Var(flag_pcc_struct_return,0) Optimization
1684 Return small aggregates in registers
1687 Common Report Var(flag_regmove) Optimization
1688 Enables a register move optimization
1691 Common Report Var(flag_rename_registers) Init(2) Optimization
1692 Perform a register renaming optimization pass
1695 Common Report Var(flag_reorder_blocks) Optimization
1696 Reorder basic blocks to improve code placement
1698 freorder-blocks-and-partition
1699 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1700 Reorder basic blocks and partition into hot and cold sections
1703 Common Report Var(flag_reorder_functions) Optimization
1704 Reorder functions to improve code placement
1706 frerun-cse-after-loop
1707 Common Report Var(flag_rerun_cse_after_loop) Optimization
1708 Add a common subexpression elimination pass after loop optimizations
1712 Does nothing. Preserved for backward compatibility.
1715 Common Report Var(flag_rounding_math) Optimization SetByCombined
1716 Disable optimizations that assume default FP rounding behavior
1719 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1720 Enable scheduling across basic blocks
1723 Common Report Var(flag_sched_pressure) Init(0) Optimization
1724 Enable register pressure sensitive insn scheduling
1727 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1728 Allow speculative motion of non-loads
1731 Common Report Var(flag_schedule_speculative_load) Optimization
1732 Allow speculative motion of some loads
1734 fsched-spec-load-dangerous
1735 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1736 Allow speculative motion of more loads
1739 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1740 -fsched-verbose=<number> Set the verbosity level of the scheduler
1742 fsched2-use-superblocks
1743 Common Report Var(flag_sched2_use_superblocks) Optimization
1744 If scheduling post reload, do superblock scheduling
1748 Does nothing. Preserved for backward compatibility.
1751 Common Report Var(flag_schedule_insns) Optimization
1752 Reschedule instructions before register allocation
1755 Common Report Var(flag_schedule_insns_after_reload) Optimization
1756 Reschedule instructions after register allocation
1758 ; This flag should be on when a target implements non-trivial
1759 ; scheduling hooks, maybe saving some information for its own sake.
1760 ; On IA64, for example, this is used for correct bundling.
1761 fselective-scheduling
1762 Common Report Var(flag_selective_scheduling) Optimization
1763 Schedule instructions using selective scheduling algorithm
1765 fselective-scheduling2
1766 Common Report Var(flag_selective_scheduling2) Optimization
1767 Run selective scheduling after reload
1769 fsel-sched-pipelining
1770 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1771 Perform software pipelining of inner loops during selective scheduling
1773 fsel-sched-pipelining-outer-loops
1774 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1775 Perform software pipelining of outer loops during selective scheduling
1777 fsel-sched-reschedule-pipelined
1778 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1779 Reschedule pipelined regions without pipelining
1781 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1782 ; of stalled insns into the ready list.
1783 fsched-stalled-insns
1784 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1785 Allow premature scheduling of queued insns
1787 fsched-stalled-insns=
1788 Common RejectNegative Joined UInteger
1789 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1791 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1792 ; be examined for a dependency on a stalled insn that is candidate for
1793 ; premature removal from the queue of stalled insns into the ready list (has
1794 ; an effect only if the flag 'sched_stalled_insns' is set).
1795 fsched-stalled-insns-dep
1796 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1797 Set dependence distance checking in premature scheduling of queued insns
1799 fsched-stalled-insns-dep=
1800 Common RejectNegative Joined UInteger
1801 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1803 fsched-group-heuristic
1804 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1805 Enable the group heuristic in the scheduler
1807 fsched-critical-path-heuristic
1808 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1809 Enable the critical path heuristic in the scheduler
1811 fsched-spec-insn-heuristic
1812 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1813 Enable the speculative instruction heuristic in the scheduler
1815 fsched-rank-heuristic
1816 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1817 Enable the rank heuristic in the scheduler
1819 fsched-last-insn-heuristic
1820 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1821 Enable the last instruction heuristic in the scheduler
1823 fsched-dep-count-heuristic
1824 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1825 Enable the dependent count heuristic in the scheduler
1828 Common Report Var(flag_section_anchors) Optimization
1829 Access data in the same section from shared anchor points
1833 Does nothing. Preserved for backward compatibility.
1837 Does nothing. Preserved for backward compatibility.
1840 Common Report Var(flag_ree) Init(0)
1841 Turn on Redundant Extensions Elimination pass.
1844 Common Report Var(flag_show_column) Init(1)
1845 Show column numbers in diagnostics, when available. Default on
1848 Common Report Var(flag_shrink_wrap) Optimization
1849 Emit function prologues only before parts of the function that need it,
1850 rather than at the top of the function.
1853 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1854 Disable optimizations observable by IEEE signaling NaNs
1857 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1858 Disable floating point optimizations that ignore the IEEE signedness of zero
1860 fsingle-precision-constant
1861 Common Report Var(flag_single_precision_constant) Optimization
1862 Convert floating point constants to single precision constants
1864 fsplit-ivs-in-unroller
1865 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1866 Split lifetimes of induction variables when loops are unrolled
1869 Common Report Var(flag_split_stack) Init(-1)
1870 Generate discontiguous stack frames
1873 Common Report Var(flag_split_wide_types) Optimization
1874 Split wide types into independent registers
1876 fvariable-expansion-in-unroller
1877 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1878 Apply variable expansion when loops are unrolled
1881 Common Report RejectNegative Joined
1882 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1885 Common Alias(fstack-check=, specific, no)
1886 Insert stack checking code into the program. Same as -fstack-check=specific
1889 Common Var(common_deferred_options) Defer
1891 fstack-limit-register=
1892 Common RejectNegative Joined Var(common_deferred_options) Defer
1893 -fstack-limit-register=<register> Trap if the stack goes past <register>
1895 fstack-limit-symbol=
1896 Common RejectNegative Joined Var(common_deferred_options) Defer
1897 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1900 Common Report Var(flag_stack_protect, 1)
1901 Use propolice as a stack protection method
1903 fstack-protector-all
1904 Common Report RejectNegative Var(flag_stack_protect, 2)
1905 Use a stack protection method for every function
1908 Common RejectNegative Var(flag_stack_usage)
1909 Output stack usage information on a per-function basis
1913 Does nothing. Preserved for backward compatibility.
1915 ; Nonzero if we should do (language-dependent) alias analysis.
1916 ; Typically, this analysis will assume that expressions of certain
1917 ; types do not alias expressions of certain other types. Only used
1918 ; if alias analysis (in general) is enabled.
1920 Common Report Var(flag_strict_aliasing) Optimization
1921 Assume strict aliasing rules apply
1924 Common Report Var(flag_strict_overflow)
1925 Treat signed overflow as undefined
1928 Common Report Var(flag_sync_libcalls) Init(1)
1929 Implement __atomic operations via libcalls to legacy __sync functions
1932 Common Report Var(flag_syntax_only)
1933 Check for syntax errors, then stop
1936 Common Report Var(flag_test_coverage)
1937 Create data files needed by \"gcov\"
1940 Common Report Var(flag_thread_jumps) Optimization
1941 Perform jump threading optimizations
1944 Common Report Var(time_report)
1945 Report the time taken by each compiler pass
1948 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1949 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1952 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1955 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1958 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1961 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1964 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1967 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1968 Reorder top level functions, variables, and asms
1971 Common Report Var(flag_tracer)
1972 Perform superblock formation via tail duplication
1974 ; Zero means that floating-point math operations cannot generate a
1975 ; (user-visible) trap. This is the case, for example, in nonstop
1976 ; IEEE 754 arithmetic.
1978 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1979 Assume floating-point operations can trap
1982 Common Report Var(flag_trapv) Optimization
1983 Trap for signed overflow in addition, subtraction and multiplication
1986 Common Report Var(flag_tree_ccp) Optimization
1987 Enable SSA-CCP optimization on trees
1990 Common Report Var(flag_tree_bit_ccp) Optimization
1991 Enable SSA-BIT-CCP optimization on trees
1995 Does nothing. Preserved for backward compatibility.
1998 Common Report Var(flag_tree_ch) Optimization
1999 Enable loop header copying on trees
2001 ftree-coalesce-inlined-vars
2002 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
2003 Enable coalescing of copy-related user variables that are inlined
2006 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
2007 Enable coalescing of all copy-related user variables
2010 Common Report Var(flag_tree_copyrename) Optimization
2011 Replace SSA temporaries with better names in copies
2014 Common Report Var(flag_tree_copy_prop) Optimization
2015 Enable copy propagation on trees
2017 ftree-store-copy-prop
2019 Does nothing. Preserved for backward compatibility.
2022 Common Report Var(flag_tree_cselim) Init(2) Optimization
2023 Transform condition stores into unconditional ones
2025 ftree-switch-conversion
2026 Common Report Var(flag_tree_switch_conversion) Optimization
2027 Perform conversions of switch initializations.
2030 Common Report Var(flag_tree_dce) Optimization
2031 Enable SSA dead code elimination optimization on trees
2033 ftree-dominator-opts
2034 Common Report Var(flag_tree_dom) Optimization
2035 Enable dominator optimizations
2038 Common Report Var(flag_tree_tail_merge) Optimization
2039 Enable tail merging on trees
2042 Common Report Var(flag_tree_dse) Optimization
2043 Enable dead store elimination
2046 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2047 Enable forward propagation on trees
2050 Common Report Var(flag_tree_fre) Optimization
2051 Enable Full Redundancy Elimination (FRE) on trees
2054 Common Report Var(flag_optimize_strlen) Optimization
2055 Enable string length optimizations on trees
2057 ftree-loop-distribution
2058 Common Report Var(flag_tree_loop_distribution) Optimization
2059 Enable loop distribution on trees
2061 ftree-loop-distribute-patterns
2062 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2063 Enable loop distribution for patterns transformed into a library call
2066 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2067 Enable loop invariant motion on trees
2070 Common Alias(floop-interchange)
2071 Enable loop interchange transforms. Same as -floop-interchange
2074 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2075 Create canonical induction variables in loops
2078 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2079 Enable loop optimizations on tree level
2081 ftree-parallelize-loops=
2082 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2083 Enable automatic parallelization of loops
2086 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2087 Enable hoisting loads from conditional pointers.
2090 Common Report Var(flag_tree_pre) Optimization
2091 Enable SSA-PRE optimization on trees
2094 Common Report Var(flag_tree_partial_pre) Optimization
2095 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2098 Common Report Var(flag_tree_pta) Init(1) Optimization
2099 Perform function-local points-to analysis on trees.
2102 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2103 Enable reassociation on tree level
2107 Does nothing. Preserved for backward compatibility.
2110 Common Report Var(flag_tree_sink) Optimization
2111 Enable SSA code sinking on trees
2114 Common Report Var(flag_tree_slsr) Optimization
2115 Perform straight-line strength reduction
2118 Common Report Var(flag_tree_sra) Optimization
2119 Perform scalar replacement of aggregates
2122 Common Report Var(flag_tree_ter) Optimization
2123 Replace temporary expressions in the SSA->normal pass
2126 Common Report Var(flag_tree_live_range_split) Optimization
2127 Perform live range splitting during the SSA->normal pass
2130 Common Report Var(flag_tree_vrp) Init(0) Optimization
2131 Perform Value Range Propagation on trees
2134 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2135 Compile whole compilation unit at a time
2138 Common Report Var(flag_unroll_loops) Optimization
2139 Perform loop unrolling when iteration count is known
2142 Common Report Var(flag_unroll_all_loops) Optimization
2143 Perform loop unrolling for all loops
2145 ; Nonzero means that loop optimizer may assume that the induction variables
2146 ; that control loops do not overflow and that the loops with nontrivial
2147 ; exit condition are not infinite
2148 funsafe-loop-optimizations
2149 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2150 Allow loop optimizations to assume that the loops behave in normal way
2153 Common Report Var(flag_associative_math) SetByCombined
2154 Allow optimization for floating-point arithmetic which may change the
2155 result of the operation due to rounding.
2158 Common Report Var(flag_reciprocal_math) SetByCombined
2159 Same as -fassociative-math for expressions which include division.
2161 ; Nonzero means that unsafe floating-point math optimizations are allowed
2162 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2163 ; are allowed to assume that their arguments and results are "normal"
2164 ; (e.g., nonnegative for SQRT).
2165 funsafe-math-optimizations
2166 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2167 Allow math optimizations that may violate IEEE or ISO standards
2170 Common Report Var(flag_unswitch_loops) Optimization
2171 Perform loop unswitching
2174 Common Report Var(flag_unwind_tables) Optimization
2175 Just generate unwind tables for exception handling
2178 Common Negative(fuse-ld=gold)
2179 Use the bfd linker instead of the default linker
2182 Common Negative(fuse-ld=bfd)
2183 Use the gold linker instead of the default linker
2188 ; Positive if we should track variables, negative if we should run
2189 ; the var-tracking pass only to discard debug annotations, zero if
2190 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2191 ; will be set according to optimize, debug_info_level and debug_hooks
2192 ; in process_options ().
2194 Common Report Var(flag_var_tracking) Init(2) Optimization
2195 Perform variable tracking
2197 ; Positive if we should track variables at assignments, negative if
2198 ; we should run the var-tracking pass only to discard debug
2199 ; annotations. When flag_var_tracking_assignments ==
2200 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2201 fvar-tracking-assignments
2202 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2203 Perform variable tracking by annotating assignments
2205 ; Nonzero if we should toggle flag_var_tracking_assignments after
2206 ; processing options and computing its default. */
2207 fvar-tracking-assignments-toggle
2208 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2209 Toggle -fvar-tracking-assignments
2211 ; Positive if we should track uninitialized variables, negative if
2212 ; we should run the var-tracking pass only to discard debug
2213 ; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
2214 ; will be set according to flag_var_tracking.
2215 fvar-tracking-uninit
2216 Common Report Var(flag_var_tracking_uninit) Optimization
2217 Perform variable tracking and also tag variables that are uninitialized
2220 Common Report Var(flag_tree_vectorize) Optimization
2221 Enable loop vectorization on trees
2223 ftree-vectorizer-verbose=
2224 Common RejectNegative Joined UInteger Var(common_deferred_options) Defer
2225 -ftree-vectorizer-verbose=<number> This switch is deprecated. Use -fopt-info instead.
2228 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2229 Enable basic block vectorization (SLP) on trees
2232 Common Report Var(flag_vect_cost_model) Optimization
2233 Enable use of cost model in vectorization
2235 ftree-vect-loop-version
2236 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2237 Enable loop versioning when doing loop vectorization on trees
2240 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2241 Enable copy propagation of scalar-evolution information.
2243 ; -fverbose-asm causes extra commentary information to be produced in
2244 ; the generated assembly code (to make it more readable). This option
2245 ; is generally only of use to those who actually need to read the
2246 ; generated assembly code (perhaps while debugging the compiler itself).
2247 ; -fno-verbose-asm, the default, causes the extra information
2248 ; to not be added and is useful when comparing two assembler files.
2250 Common Report Var(flag_verbose_asm)
2251 Add extra commentary to assembler output
2254 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2255 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2258 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2261 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2264 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2267 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2270 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2273 Common Report Var(flag_value_profile_transformations) Optimization
2274 Use expression value profiles in optimizations
2277 Common Report Var(flag_web) Init(2) Optimization
2278 Construct webs and split unrelated uses of single variable
2280 ftree-builtin-call-dce
2281 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2282 Enable conditional dead code elimination for builtin calls
2285 Common Report Var(flag_whole_program) Init(0) Optimization
2286 Perform whole program optimizations
2289 Common Report Var(flag_wrapv) Optimization
2290 Assume signed arithmetic overflow wraps around
2292 fzero-initialized-in-bss
2293 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2294 Put zero initialized data in the bss section
2297 Common JoinedOrMissing
2298 Generate debug information in default format
2301 Common JoinedOrMissing Negative(gdwarf-)
2302 Generate debug information in COFF format
2305 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2306 Generate debug information in DWARF v2 (or later) format
2309 Common JoinedOrMissing
2310 Generate debug information in default extended format
2313 Common RejectNegative Var(debug_generate_pub_sections, 0) Init(-1)
2314 Don't generate DWARF pubnames and pubtypes sections.
2317 Common RejectNegative Var(debug_generate_pub_sections, 1)
2318 Generate DWARF pubnames and pubtypes sections.
2320 gno-record-gcc-switches
2321 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2322 Don't record gcc command line switches in DWARF DW_AT_producer.
2324 grecord-gcc-switches
2325 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2326 Record gcc command line switches in DWARF DW_AT_producer.
2329 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2330 Don't generate debug information in separate .dwo files
2333 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2334 Generate debug information in separate .dwo files
2337 Common JoinedOrMissing Negative(gstabs+)
2338 Generate debug information in STABS format
2341 Common JoinedOrMissing Negative(gvms)
2342 Generate debug information in extended STABS format
2345 Common RejectNegative Var(dwarf_strict,0) Init(0)
2346 Emit DWARF additions beyond selected version
2349 Common Report RejectNegative Var(dwarf_strict,1)
2350 Don't emit DWARF additions beyond selected version
2353 Common Report Var(flag_gtoggle)
2354 Toggle debug information generation
2357 Common JoinedOrMissing Negative(gxcoff)
2358 Generate debug information in VMS format
2361 Common JoinedOrMissing Negative(gxcoff+)
2362 Generate debug information in XCOFF format
2365 Common JoinedOrMissing Negative(gcoff)
2366 Generate debug information in extended XCOFF format
2369 Driver Joined Separate
2372 Common Joined Var(plugindir_string) Init(0)
2373 -iplugindir=<dir> Set <dir> to be the default plugin directory
2376 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2377 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory
2380 Driver Joined Separate
2385 no-canonical-prefixes
2398 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2399 -o <file> Place output into <file>
2402 Common Var(profile_flag)
2403 Enable function profiling
2406 Driver Var(pass_exit_codes)
2409 Common Alias(Wpedantic)
2412 Common Var(flag_pedantic_errors)
2413 Like -pedantic but issue them as errors
2419 Driver Var(use_pipes)
2422 Driver JoinedOrMissing Var(print_file_name)
2424 print-libgcc-file-name
2427 print-multi-directory
2428 Driver Var(print_multi_directory)
2431 Driver Var(print_multi_lib)
2433 print-multi-os-directory
2434 Driver Var(print_multi_os_directory)
2437 Driver Var(print_multiarch)
2440 Driver JoinedOrMissing Var(print_prog_name)
2443 Driver Var(print_search_dirs)
2446 Driver Var(print_sysroot)
2448 print-sysroot-headers-suffix
2449 Driver Var(print_sysroot_headers_suffix)
2452 Common Var(quiet_flag) RejectDriver
2453 Do not display functions compiled or elapsed time
2471 Driver Var(report_times)
2474 Driver JoinedOrMissing
2477 Driver Joined Separate
2481 ; C option, but driver must not handle as "-u ndef".
2484 Common Driver Var(verbose_flag)
2485 Enable verbose output
2488 Common Var(version_flag) RejectDriver
2489 Display the compiler's version
2492 Common Var(inhibit_warnings)
2496 Driver Separate Var(wrapper_string)
2499 Driver Joined Separate
2502 Driver RejectNegative Negative(pie)
2503 Create a shared library
2509 Driver Separate Alias(specs=)
2522 ; Documented for Fortran, but always accepted by driver.
2529 ; Documented for Go, but always accepted by driver.
2541 Driver RejectNegative Negative(shared)
2542 Create a position independent executable
2545 Driver Joined Separate
2547 ; This comment is to ensure we retain the blank line above.