1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
4 ; Free Software Foundation, Inc.
6 ; This file is part of GCC.
8 ; GCC is free software; you can redistribute it and/or modify it under
9 ; the terms of the GNU General Public License as published by the Free
10 ; Software Foundation; either version 3, or (at your option) any later
13 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 ; You should have received a copy of the GNU General Public License
19 ; along with GCC; see the file COPYING3. If not see
20 ; <http://www.gnu.org/licenses/>.
22 ; See the GCC internals manual (options.texi) for a description of this file's format.
24 ; Please try to keep this file in ASCII collating order.
38 ; Not used directly to control optimizations, only to save -Ofast
39 ; setting for "optimize" attributes.
43 ; True if this is the lto front end. This is used to disable gimple
44 ; generation and lowering passes that are normally run on the output
45 ; of a front end. These passes must be bypassed for lto since they
46 ; have already been done before the gimple was written.
50 ; 0 means straightforward implementation of complex divide acceptable.
51 ; 1 means wide ranges of inputs must work for complex divide.
52 ; 2 means C99-like requirements for complex multiply and divide.
54 int flag_complex_method = 1
56 ; Nonzero if subexpressions must be evaluated from left-to-right.
58 int flag_evaluation_order = 0
60 ; Language specific warning pass for unused results.
62 bool flag_warn_unused_result = false
67 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
71 ; True to warn about any objects definitions whose size is larger
72 ; than N bytes. Also want about function definitions whose returned
73 ; values are larger than N bytes, where N is 'larger_than_size'.
78 HOST_WIDE_INT larger_than_size
80 ; True to warn about any function whose frame size is larger
83 bool warn_frame_larger_than
86 HOST_WIDE_INT frame_larger_than_size
88 ; Nonzero means we should be saving declaration info into a .X file.
90 int flag_gen_aux_info = 0
92 ; Nonzero if we are compiling code for a shared library, zero for
97 ; These two are really VEC(char_p,heap) *.
100 void *flag_instrument_functions_exclude_functions
103 void *flag_instrument_functions_exclude_files
105 ; Generic structs (e.g. templates not explicitly specialized)
106 ; may not have a compilation unit associated with them, and so
107 ; may need to be treated differently from ordinary structs.
109 ; Structs only handled by reference (indirectly), will also usually
110 ; not need as much debugging information.
113 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
116 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
118 ; True if we should exit after parsing options.
120 bool exit_after_options
122 ; Type(s) of debugging information we are producing (if any). See
123 ; flag-types.h for the definitions of the different possible types of
124 ; debugging information.
126 enum debug_info_type write_symbols = NO_DEBUG
128 ; Level of debugging information we are producing. See flag-types.h
129 ; for the definitions of the different possible levels.
131 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
133 ; Nonzero means use GNU-only extensions in the generated symbolic
134 ; debugging information. Currently, this only has an effect when
135 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
137 bool use_gnu_debug_info_extensions
139 ; Original value of maximum field alignment in bytes, specified via
140 ; -fpack-struct=<value>.
142 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
145 enum vect_verbosity_levels user_vect_verbosity_level = MAX_VERBOSITY_LEVEL
147 ; Type of stack check.
149 enum stack_check_type flag_stack_check = NO_STACK_CHECK
151 ; True if stack usage information needs to be computed.
153 bool flag_stack_usage_info = false
155 ; -dA causes debug commentary information to be produced in
156 ; the generated assembly code (to make it more readable). This option
157 ; is generally only of use to those who actually need to read the
158 ; generated assembly code (perhaps while debugging the compiler itself).
159 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
160 ; to be a catchall for printing debug information in the assembler file.
164 ; -dP causes the rtl to be emitted as a comment in assembly.
166 int flag_dump_rtl_in_asm
168 ; Whether -da was passed (used only in handle_common_deferred_options).
170 bool flag_dump_all_passed
172 ; Other flags saying which kinds of debugging dump have been requested.
175 int rtl_dump_and_exit
178 int flag_print_asm_name
181 enum graph_dump_types graph_dump_format = no_graph
183 ; Name of top-level original source file (what was input to cpp).
184 ; This comes from the #-command at the beginning of the actual input.
185 ; If there isn't any there, then this is the cc1 input file name.
187 const char *main_input_filename
189 ; Pointer to base name in main_input_filename, with directories and a
190 ; single final extension removed, and the length of this base
194 const char *main_input_basename
197 int main_input_baselength
199 ; Which options have been printed by --help.
203 ; Which enums have been printed by --help. 0 = not printed, no
204 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
207 char *help_enum_printed
209 ; The number of columns for --help output.
211 unsigned int help_columns
213 ; Whether this options structure has been through finish_options
215 bool flag_opts_finished
227 Driver Alias(coverage)
233 Common Separate Alias(d)
236 Common Joined Alias(d)
239 Common Separate Alias(dumpbase)
242 Common Separate Alias(dumpdir)
245 Driver Separate Alias(e)
248 Driver Joined Alias(e)
251 Common Warning Alias(Wextra)
254 Driver Separate Alias(Xassembler)
257 Driver JoinedOrMissing Alias(Xassembler)
260 Driver Separate Alias(Xlinker)
263 Driver JoinedOrMissing Alias(Xlinker)
266 Driver Separate Alias(u)
269 Driver Joined Alias(u)
272 Common Driver Var(help_flag)
273 Display this information
276 Common Driver Report Joined
277 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
280 Driver Separate Alias(x)
283 Driver Joined Alias(x)
286 Driver Separate Alias(L)
289 Driver Joined Alias(L)
291 -no-canonical-prefixes
292 Driver Alias(no-canonical-prefixes)
294 -no-standard-libraries
295 Driver Alias(nostdlib)
298 Driver Var(no_sysroot_suffix)
307 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
310 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
313 Driver Alias(pass-exit-codes)
316 Common Alias(Wpedantic)
319 Common Alias(pedantic-errors)
328 Driver Separate Alias(B)
331 Driver JoinedOrMissing Alias(B)
337 Driver Separate Alias(print-file-name=)
340 Driver JoinedOrMissing Alias(print-file-name=)
342 -print-libgcc-file-name
343 Driver Alias(print-libgcc-file-name)
345 -print-multi-directory
346 Driver Alias(print-multi-directory)
349 Driver Alias(print-multi-lib)
351 -print-multi-os-directory
352 Driver Alias(print-multi-os-directory)
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
513 Common Var(warn_array_bounds) Warning
514 Warn if an array is accessed out of bounds
517 Common Var(warn_attributes) Init(1) Warning
518 Warn about inappropriate attribute usage
521 Common Var(warn_cast_align) Warning
522 Warn about pointer casts which increase alignment
525 Common Var(warn_cpp) Init(1) Warning
526 Warn when a #warning directive is encountered
528 Wdeprecated-declarations
529 Common Var(warn_deprecated_decl) Init(1) Warning
530 Warn about uses of __attribute__((deprecated)) declarations
532 Wdisabled-optimization
533 Common Var(warn_disabled_optimization) Warning
534 Warn when an optimization pass is disabled
537 Common Var(warnings_are_errors)
538 Treat all warnings as errors
542 Treat specified warning as error
545 Common Var(extra_warnings) Warning
546 Print extra (possibly unwanted) warnings
549 Common Var(flag_fatal_errors)
550 Exit on the first error occurred
553 Common RejectNegative Joined UInteger
554 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
557 Common Var(warn_free_nonheap_object) Init(1) Warning
558 Warn when attempting to free a non-heap object
561 Common Var(warn_inline) Warning
562 Warn when an inlined function cannot be inlined
564 Winvalid-memory-model
565 Common Var(warn_invalid_memory_model) Init(1) Warning
566 Warn when an atomic memory model parameter is known to be outside the valid range.
569 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
572 Common RejectNegative Joined UInteger Warning
573 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
575 Wunsafe-loop-optimizations
576 Common Var(warn_unsafe_loop_optimizations) Warning
577 Warn if the loop cannot be optimized due to nontrivial assumptions.
580 Common Alias(Wsuggest-attribute=noreturn)
583 Common Var(warn_overflow) Init(1) Warning
584 Warn about overflow in arithmetic expressions
587 Common Var(warn_packed) Warning
588 Warn when the packed attribute has no effect on struct layout
591 Common Var(warn_padded) Warning
592 Warn when padding is required to align structure members
595 Common Var(pedantic) Warning
596 Issue warnings needed for strict compliance to the standard
599 Common Var(warn_shadow) Warning
600 Warn when one local variable shadows another
603 Common Var(warn_stack_protect) Warning
604 Warn when not issuing stack smashing protection for some reason
607 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
608 Warn if stack usage might be larger than specified amount
612 Warn about code which might break strict aliasing rules
615 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
616 Warn about code which might break strict aliasing rules
620 Warn about optimizations that assume that signed overflow is undefined
623 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
624 Warn about optimizations that assume that signed overflow is undefined
626 Wsuggest-attribute=const
627 Common Var(warn_suggest_attribute_const) Warning
628 Warn about functions which might be candidates for __attribute__((const))
630 Wsuggest-attribute=pure
631 Common Var(warn_suggest_attribute_pure) Warning
632 Warn about functions which might be candidates for __attribute__((pure))
634 Wsuggest-attribute=noreturn
635 Common Var(warn_suggest_attribute_noreturn) Warning
636 Warn about functions which might be candidates for __attribute__((noreturn))
639 Common Var(warn_switch) Warning
640 Warn about enumerated switches, with no default, missing a case
643 Common Var(warn_switch_default) Warning
644 Warn about enumerated switches missing a \"default:\" statement
647 Common Var(warn_switch_enum) Warning
648 Warn about all enumerated switches missing a specific case
651 Common Var(warn_system_headers) Warning
652 Do not suppress warnings from system headers
655 Common Var(warn_trampolines) Warning
656 Warn whenever a trampoline is generated
659 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
660 Warn if a comparison is always true or always false due to the limited range of the data type
663 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
664 Warn about uninitialized automatic variables
667 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
668 Warn about maybe uninitialized automatic variables
672 Does nothing. Preserved for backward compatibility.
675 Common Var(warn_unused) Init(0) Warning
676 Enable all -Wunused- warnings
678 Wunused-but-set-parameter
679 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
680 Warn when a function parameter is only set, otherwise unused
682 Wunused-but-set-variable
683 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
684 Warn when a variable is only set, otherwise unused
687 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
688 Warn when a function is unused
691 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
692 Warn when a label is unused
695 Common Var(warn_unused_parameter) Init(-1) Warning
696 Warn when a function parameter is unused
699 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
700 Warn when an expression value is unused
703 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
704 Warn when a variable is unused
707 Common Var(warn_coverage_mismatch) Init(1) Warning
708 Warn in case profiles in -fprofile-use do not match
710 Wvector-operation-performance
711 Common Var(warn_vector_operation_performance) Warning
712 Warn when a vector operation is compiled outside the SIMD
727 Common Separate Var(aux_info_file_name)
728 -aux-info <file> Emit declaration information into <file>
731 Common Joined Alias(aux-info)
734 Common Separate RejectDriver Var(aux_base_name)
737 Common Separate RejectDriver
747 -d<letters> Enable dumps from specific passes of the compiler
750 Common Separate Var(dump_base_name)
751 -dumpbase <file> Set the file basename to be used for dumps
754 Common Separate Var(dump_dir_name)
755 -dumpdir <dir> Set the directory name to be used for dumps
767 Driver Joined Separate
769 ; This option has historically been passed down to the linker by an
770 ; accident of a %{e*} spec, so ensure it continues to be passed down
771 ; as a single option. The supported option for this purpose is
772 ; -rdynamic. See PR 47390.
776 ; The version of the C++ ABI in use. The following values are allowed:
778 ; 0: The version of the ABI believed most conformant with the C++ ABI
779 ; specification. This ABI may change as bugs are discovered and fixed.
780 ; Therefore, 0 will not necessarily indicate the same ABI in different
783 ; 1: The version of the ABI first used in G++ 3.2.
785 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
787 ; 3: The version of the ABI that fixes the missing underscore
788 ; in template non-type arguments of pointer type.
790 ; 4: The version of the ABI that introduces unambiguous mangling of
791 ; vector types. First selectable in G++ 4.5.
793 ; 5: The version of the ABI that ignores attribute const/noreturn
794 ; in function pointer mangling, and corrects mangling of decltype and
795 ; function parameters used in other parameters and the return type.
796 ; First selectable in G++ 4.6.
798 ; 6: The version of the ABI that doesn't promote scoped enums to int and
799 ; changes the mangling of template argument packs, const/static_cast,
800 ; prefix ++ and --, and a class scope function used as a template
802 ; First selectable in G++ 4.7.
804 ; 7: The version of the ABI that treats nullptr_t as a builtin type.
805 ; First selectable in G++ 4.8.
806 ; Additional positive integers will be assigned as new versions of
807 ; the ABI become the default version of the ABI.
809 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
812 Common Report Var(align_functions,0) Optimization UInteger
813 Align the start of functions
816 Common RejectNegative Joined UInteger Var(align_functions)
819 Common Report Var(align_jumps,0) Optimization UInteger
820 Align labels which are only reached by jumping
823 Common RejectNegative Joined UInteger Var(align_jumps)
826 Common Report Var(align_labels,0) Optimization UInteger
830 Common RejectNegative Joined UInteger Var(align_labels)
833 Common Report Var(align_loops,0) Optimization UInteger
834 Align the start of loops
837 Common RejectNegative Joined UInteger Var(align_loops)
841 Does nothing. Preserved for backward compatibility.
845 Does nothing. Preserved for backward compatibility.
847 fargument-noalias-global
849 Does nothing. Preserved for backward compatibility.
851 fargument-noalias-anything
853 Does nothing. Preserved for backward compatibility.
855 fasynchronous-unwind-tables
856 Common Report Var(flag_asynchronous_unwind_tables) Optimization
857 Generate unwind tables that are exact at each instruction boundary
860 Common Report Var(flag_auto_inc_dec) Init(1)
861 Generate auto-inc/dec instructions
863 ; -fcheck-bounds causes gcc to generate array bounds checks.
864 ; For C, C++ and ObjC: defaults off.
865 ; For Java: defaults to on.
866 ; For Fortran: defaults to off.
868 Common Report Var(flag_bounds_check)
869 Generate code to check bounds before indexing arrays
872 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
873 Replace add, compare, branch with branch on count register
875 fbranch-probabilities
876 Common Report Var(flag_branch_probabilities) Optimization
877 Use profiling information for branch probabilities
879 fbranch-target-load-optimize
880 Common Report Var(flag_branch_target_load_optimize) Optimization
881 Perform branch target load optimization before prologue / epilogue threading
883 fbranch-target-load-optimize2
884 Common Report Var(flag_branch_target_load_optimize2) Optimization
885 Perform branch target load optimization after prologue / epilogue threading
888 Common Report Var(flag_btr_bb_exclusive) Optimization
889 Restrict target load migration not to re-use registers in any basic block
892 Common Joined RejectNegative Var(common_deferred_options) Defer
893 -fcall-saved-<register> Mark <register> as being preserved across functions
896 Common Joined RejectNegative Var(common_deferred_options) Defer
897 -fcall-used-<register> Mark <register> as being corrupted by function calls
899 ; Nonzero for -fcaller-saves: allocate values in regs that need to
900 ; be saved across function calls, if that produces overall better code.
901 ; Optional now, so people can test it.
903 Common Report Var(flag_caller_saves) Optimization
904 Save registers around function calls
907 Common Report Var(flag_check_data_deps)
908 Compare the results of several data dependence analyzers.
910 fcombine-stack-adjustments
911 Common Report Var(flag_combine_stack_adjustments) Optimization
912 Looks for opportunities to reduce stack adjustments and stack references.
915 Common Report Var(flag_no_common,0) Optimization
916 Do not put uninitialized globals in the common section
920 ; Converted by the driver to -fcompare-debug= options.
923 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
924 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
926 fcompare-debug-second
927 Common Driver RejectNegative Var(flag_compare_debug)
928 Run only the second compilation of -fcompare-debug
931 Common Report Var(flag_compare_elim_after_reload) Optimization
932 Perform comparison elimination after register allocation has finished
935 Common Var(flag_conserve_stack) Optimization
936 Do not perform optimizations increasing noticeably stack usage
939 Common Report Var(flag_cprop_registers) Optimization
940 Perform a register copy-propagation optimization pass
943 Common Report Var(flag_crossjumping) Optimization
944 Perform cross-jumping optimization
947 Common Report Var(flag_cse_follow_jumps) Optimization
948 When running CSE, follow jumps to their targets
952 Does nothing. Preserved for backward compatibility.
955 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
956 Omit range reduction step when performing complex division
959 Common Report Var(flag_cx_fortran_rules) Optimization
960 Complex multiplication and division follow Fortran rules
963 Common Report Var(flag_data_sections) Optimization
964 Place data items into their own section
967 Common Report Var(common_deferred_options) Defer
968 List all available debugging counters with their limits and counts.
971 Common RejectNegative Joined Var(common_deferred_options) Defer
972 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
975 Common Joined RejectNegative Var(common_deferred_options) Defer
976 Map one directory name to another in debug information
979 Common Report Var(flag_debug_types_section) Init(0)
980 Output .debug_types section when using DWARF v4 debuginfo.
982 ; Nonzero for -fdefer-pop: don't pop args after each function call
983 ; instead save them up to pop many calls' args with one insns.
985 Common Report Var(flag_defer_pop) Optimization
986 Defer popping functions args from stack until later
989 Common Report Var(flag_delayed_branch) Optimization
990 Attempt to fill delay slots of branch instructions
992 fdelete-dead-exceptions
993 Common Report Var(flag_delete_dead_exceptions) Init(0)
994 Delete dead instructions that may throw exceptions
996 fdelete-null-pointer-checks
997 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
998 Delete useless null pointer checks
1001 Common Report Var(flag_devirtualize) Optimization
1002 Try to convert virtual calls to direct ones.
1004 fdiagnostics-show-location=
1005 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1006 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
1008 ; Required for these enum values.
1013 Name(diagnostic_prefixing_rule) Type(int)
1016 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1019 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1021 fdiagnostics-show-caret
1022 Common Var(flag_diagnostics_show_caret) Init(1)
1023 Show the source line with a caret indicating the column
1025 fdiagnostics-show-option
1026 Common Var(flag_diagnostics_show_option) Init(1)
1027 Amend appropriate diagnostic messages with the command line option that controls them
1030 Common Joined RejectNegative Var(common_deferred_options) Defer
1031 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1034 Common Joined RejectNegative Var(common_deferred_options) Defer
1035 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1038 Common Joined RejectNegative Var(common_deferred_options) Defer
1039 -fdump-<type> Dump various compiler internals to a file
1042 Driver RejectNegative
1045 Common RejectNegative Joined Var(flag_dump_final_insns)
1046 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1049 Common RejectNegative Joined Var(flag_dump_go_spec)
1050 -fdump-go-spec=filename Write all declarations to file as Go code
1053 Common Report Var(flag_dump_noaddr)
1054 Suppress output of addresses in debugging dumps
1057 Common Var(flag_dump_passes) Init(0)
1058 Dump optimization passes
1061 Common Report Var(flag_dump_unnumbered)
1062 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1064 fdump-unnumbered-links
1065 Common Report Var(flag_dump_unnumbered_links)
1066 Suppress output of previous and next insn numbers in debugging dumps
1069 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1070 Enable CFI tables via GAS assembler directives.
1073 Common Report Var(flag_early_inlining) Init(1) Optimization
1074 Perform early inlining
1076 feliminate-dwarf2-dups
1077 Common Report Var(flag_eliminate_dwarf2_dups)
1078 Perform DWARF2 duplicate elimination
1081 Common Report Var(flag_ipa_sra) Init(0) Optimization
1082 Perform interprocedural reduction of aggregates
1084 feliminate-unused-debug-symbols
1085 Common Report Var(flag_debug_only_used_symbols)
1086 Perform unused type elimination in debug info
1088 feliminate-unused-debug-types
1089 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1090 Perform unused type elimination in debug info
1092 femit-class-debug-always
1093 Common Report Var(flag_emit_class_debug_always) Init(0)
1094 Do not suppress C++ class debug information.
1097 Common Report Var(flag_exceptions) Optimization
1098 Enable exception handling
1100 fexpensive-optimizations
1101 Common Report Var(flag_expensive_optimizations) Optimization
1102 Perform a number of minor, expensive optimizations
1105 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1106 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1109 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1112 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1115 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1121 Common Var(flag_fat_lto_objects) Init(1)
1122 Output lto objects containing both the intermediate language and binary output.
1125 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1126 Assume no NaNs or infinities are generated
1129 Common Joined RejectNegative Var(common_deferred_options) Defer
1130 -ffixed-<register> Mark <register> as being unavailable to the compiler
1133 Common Report Var(flag_float_store) Optimization
1134 Don't allocate floats and doubles in extended-precision registers
1138 Does nothing. Preserved for backward compatibility.
1141 Common Report Var(flag_forward_propagate) Optimization
1142 Perform a forward propagation pass on RTL
1145 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1146 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1149 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1152 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1154 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1156 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1159 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1161 ; Nonzero means don't put addresses of constant functions in registers.
1162 ; Used for compiling the Unix kernel, where strange substitutions are
1163 ; done on the assembly output.
1165 Common Report Var(flag_no_function_cse,0)
1166 Allow function addresses to be held in registers
1169 Common Report Var(flag_function_sections)
1170 Place each function into its own section
1173 Common Report Var(flag_gcse) Optimization
1174 Perform global common subexpression elimination
1177 Common Report Var(flag_gcse_lm) Init(1) Optimization
1178 Perform enhanced load motion during global common subexpression elimination
1181 Common Report Var(flag_gcse_sm) Init(0) Optimization
1182 Perform store motion after global common subexpression elimination
1185 Common Report Var(flag_gcse_las) Init(0) Optimization
1186 Perform redundant load after store elimination in global common subexpression
1190 Common Report Var(flag_gcse_after_reload) Optimization
1191 Perform global common subexpression elimination after register allocation
1194 ; This option is not documented yet as its semantics will change.
1196 Common Report Var(flag_graphite)
1197 Enable in and out of Graphite representation
1200 Common Report Var(flag_graphite_identity) Optimization
1201 Enable Graphite Identity transformation
1203 fhoist-adjacent-loads
1204 Common Report Var(flag_hoist_adjacent_loads) Optimization
1205 Enable hoisting adjacent loads to encourage generating conditional move
1208 floop-parallelize-all
1209 Common Report Var(flag_loop_parallelize_all) Optimization
1210 Mark all loops as parallel
1213 Common Report Var(flag_loop_strip_mine) Optimization
1214 Enable Loop Strip Mining transformation
1217 Common Report Var(flag_loop_interchange) Optimization
1218 Enable Loop Interchange transformation
1221 Common Report Var(flag_loop_block) Optimization
1222 Enable Loop Blocking transformation
1225 Common Report Var(flag_tm)
1226 Enable support for GNU transactional memory
1230 Does nothing. Preserved for backward compatibility.
1233 Common Report Var(flag_loop_optimize_isl) Optimization
1234 Enable the ISL based loop nest optimizer
1236 fstrict-volatile-bitfields
1237 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1238 Force bitfield accesses to match their type width
1240 fguess-branch-probability
1241 Common Report Var(flag_guess_branch_prob) Optimization
1242 Enable guessing of branch probabilities
1244 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1245 ; Generate position-independent code for executables if possible
1246 ; On SVR4 targets, it also controls whether or not to emit a
1247 ; string identifying the compiler.
1249 Common Report Var(flag_no_ident,0)
1250 Process #ident directives
1253 Common Report Var(flag_if_conversion) Optimization
1254 Perform conversion of conditional jumps to branchless equivalents
1257 Common Report Var(flag_if_conversion2) Optimization
1258 Perform conversion of conditional jumps to conditional execution
1261 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL)
1262 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1265 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1268 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1271 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1274 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1276 ftree-loop-if-convert
1277 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1278 Convert conditional jumps in innermost loops to branchless equivalents
1280 ftree-loop-if-convert-stores
1281 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1282 Also if-convert conditional jumps containing memory writes
1284 ; -finhibit-size-directive inhibits output of .size for ELF.
1285 ; This is used only for compiling crtstuff.c,
1286 ; and it may be extended to other effects
1287 ; needed for crtstuff.c on other systems.
1288 finhibit-size-directive
1289 Common Report Var(flag_inhibit_size_directive)
1290 Do not generate .size directives
1293 Common Report Var(flag_indirect_inlining)
1294 Perform indirect inlining
1296 ; General flag to enable inlining. Specifying -fno-inline will disable
1297 ; all inlining apart from always-inline functions.
1299 Common Report Var(flag_no_inline,0) Init(0) Optimization
1300 Enable inlining of function declared \"inline\", disabling disables all inlining
1302 finline-small-functions
1303 Common Report Var(flag_inline_small_functions) Optimization
1304 Integrate functions into their callers when code size is known not to grow
1307 Common Report Var(flag_inline_functions) Optimization
1308 Integrate functions not declared \"inline\" into their callers when profitable
1310 finline-functions-called-once
1311 Common Report Var(flag_inline_functions_called_once) Optimization
1312 Integrate functions only required by their single caller
1315 Common RejectNegative Joined Alias(finline-limit=)
1318 Common RejectNegative Joined UInteger
1319 -finline-limit=<number> Limit the size of inlined functions to <number>
1322 Common Report Var(flag_inline_atomics) Init(1) Optimization
1323 Inline __atomic operations when a lock free instruction sequence is available.
1325 finstrument-functions
1326 Common Report Var(flag_instrument_function_entry_exit)
1327 Instrument function entry and exit with profiling calls
1329 finstrument-functions-exclude-function-list=
1330 Common RejectNegative Joined
1331 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1333 finstrument-functions-exclude-file-list=
1334 Common RejectNegative Joined
1335 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1338 Common Report Var(flag_ipa_cp) Optimization
1339 Perform Interprocedural constant propagation
1342 Common Report Var(flag_ipa_cp_clone) Optimization
1343 Perform cloning to make Interprocedural constant propagation stronger
1346 Common Report Var(flag_ipa_profile) Init(0) Optimization
1347 Perform interprocedural profile propagation
1350 Common Report Var(flag_ipa_pta) Init(0) Optimization
1351 Perform interprocedural points-to analysis
1354 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1355 Discover pure and const functions
1358 Common Report Var(flag_ipa_reference) Init(0) Optimization
1359 Discover readonly and non addressable static variables
1363 Does nothing. Preserved for backward compatibility.
1367 Does nothing. Preserved for backward compatibility.
1370 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1371 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1374 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1377 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1380 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1383 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1384 -fira-region=[one|all|mixed] Set regions for IRA
1387 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1390 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1393 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1396 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1399 Common Report Var(flag_ira_loop_pressure)
1400 Use IRA based register pressure calculation
1401 in RTL loop optimizations.
1403 fira-share-save-slots
1404 Common Report Var(flag_ira_share_save_slots) Init(1)
1405 Share slots for saving different hard registers.
1407 fira-share-spill-slots
1408 Common Report Var(flag_ira_share_spill_slots) Init(1)
1409 Share stack slots for spilled pseudo-registers.
1412 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1413 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1416 Common Report Var(flag_ivopts) Init(1) Optimization
1417 Optimize induction variables on trees
1420 Common Var(flag_jump_tables) Init(1) Optimization
1421 Use jump tables for sufficiently large switch statements
1423 fkeep-inline-functions
1424 Common Report Var(flag_keep_inline_functions)
1425 Generate code for functions even if they are fully inlined
1428 Common Report Var(flag_keep_static_consts) Init(1)
1429 Emit static const variables even if they are not used
1432 Common Report Var(flag_leading_underscore) Init(-1)
1433 Give external symbols a leading underscore
1437 Does nothing. Preserved for backward compatibility.
1441 Enable link-time optimization.
1444 Common RejectNegative Joined Var(flag_lto)
1445 Link-time optimization with number of parallel jobs or jobserver.
1448 Common Var(flag_lto_partition_1to1)
1449 Partition symbols and vars at linktime based on object files they originate from
1451 flto-partition=balanced
1452 Common Var(flag_lto_partition_balanced)
1453 Partition functions and vars at linktime into approximately same sized buckets
1456 Common Var(flag_lto_partition_max)
1457 Put every symbol into separate partition
1460 Common Var(flag_lto_partition_none)
1461 Disable partioning and streaming
1463 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1464 flto-compression-level=
1465 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1466 -flto-compression-level=<number> Use zlib compression level <number> for IL
1469 Common Report Var(flag_lto_report) Init(0)
1470 Report various link-time optimization statistics
1473 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1474 Set errno after built-in math functions
1477 Common Joined RejectNegative UInteger Var(flag_max_errors)
1478 -fmax-errors=<number> Maximum number of errors to report
1481 Common Report Var(mem_report)
1482 Report on permanent memory allocation
1485 Common Report Var(mem_report_wpa)
1486 Report on permanent memory allocation in WPA only
1488 ; This will attempt to merge constant section constants, if 1 only
1489 ; string constants and constants from constant pool, if 2 also constant
1491 fmerge-all-constants
1492 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1493 Attempt to merge identical constants and constant variables
1496 Common Report Var(flag_merge_constants,1) Optimization
1497 Attempt to merge identical constants across compilation units
1499 fmerge-debug-strings
1500 Common Report Var(flag_merge_debug_strings) Init(1)
1501 Attempt to merge identical debug strings across compilation units
1504 Common RejectNegative Joined UInteger
1505 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1508 Common Report Var(flag_modulo_sched) Optimization
1509 Perform SMS based modulo scheduling before the first scheduling pass
1511 fmodulo-sched-allow-regmoves
1512 Common Report Var(flag_modulo_sched_allow_regmoves)
1513 Perform SMS based modulo scheduling with register moves allowed
1515 fmove-loop-invariants
1516 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1517 Move loop invariant computations out of loops
1520 Common Var(flag_dce) Init(1) Optimization
1521 Use the RTL dead code elimination pass
1524 Common Var(flag_dse) Init(1) Optimization
1525 Use the RTL dead store elimination pass
1527 freschedule-modulo-scheduled-loops
1528 Common Report Var(flag_resched_modulo_sched) Optimization
1529 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1531 fnon-call-exceptions
1532 Common Report Var(flag_non_call_exceptions) Optimization
1533 Support synchronous non-call exceptions
1536 Common Report Var(flag_omit_frame_pointer) Optimization
1537 When possible do not generate stack frames
1539 foptimize-register-move
1540 Common Report Var(flag_regmove) Optimization
1541 Do the full register move optimization pass
1543 foptimize-sibling-calls
1544 Common Report Var(flag_optimize_sibling_calls) Optimization
1545 Optimize sibling and tail recursive calls
1548 Common Report Var(flag_partial_inlining)
1549 Perform partial inlining
1552 Common Report Var(pre_ipa_mem_report)
1553 Report on memory allocation before interprocedural optimization
1555 fpost-ipa-mem-report
1556 Common Report Var(post_ipa_mem_report)
1557 Report on memory allocation before interprocedural optimization
1560 Common Report Var(flag_pack_struct) Optimization
1561 Pack structure members together without holes
1564 Common RejectNegative Joined UInteger Optimization
1565 -fpack-struct=<number> Set initial maximum structure member alignment
1568 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1569 Return small aggregates in memory, not registers
1572 Common Report Var(flag_peel_loops) Optimization
1573 Perform loop peeling
1576 Common Report Var(flag_no_peephole,0) Optimization
1577 Enable machine specific peephole optimizations
1580 Common Report Var(flag_peephole2) Optimization
1581 Enable an RTL peephole pass before sched2
1584 Common Report Var(flag_pic,2)
1585 Generate position-independent code if possible (large mode)
1588 Common Report Var(flag_pie,2)
1589 Generate position-independent code for executables if possible (large mode)
1592 Common Report Var(flag_pic,1)
1593 Generate position-independent code if possible (small mode)
1596 Common Report Var(flag_pie,1)
1597 Generate position-independent code for executables if possible (small mode)
1600 Common Joined RejectNegative Var(common_deferred_options) Defer
1601 Specify a plugin to load
1604 Common Joined RejectNegative Var(common_deferred_options) Defer
1605 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1607 fpredictive-commoning
1608 Common Report Var(flag_predictive_commoning) Optimization
1609 Run predictive commoning optimization.
1611 fprefetch-loop-arrays
1612 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1613 Generate prefetch instructions, if available, for arrays in loops
1616 Common Report Var(profile_flag)
1617 Enable basic program profiling code
1620 Common Report Var(profile_arc_flag)
1621 Insert arc-based program profiling code
1624 Common Joined RejectNegative Var(profile_data_prefix)
1625 Set the top-level directory for storing the profile data.
1626 The default is 'pwd'.
1629 Common Report Var(flag_profile_correction)
1630 Enable correction of flow inconsistent profile data input
1634 Enable common options for generating profile info for profile feedback directed optimizations
1637 Common Joined RejectNegative
1638 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1641 Common Var(flag_profile_use)
1642 Enable common options for performing profile feedback directed optimizations
1645 Common Joined RejectNegative
1646 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1649 Common Report Var(flag_profile_values)
1650 Insert code to profile values of expressions
1653 Common Var(common_deferred_options) Defer
1656 Common Joined RejectNegative Var(common_deferred_options) Defer
1657 -frandom-seed=<string> Make compile reproducible using <string>
1659 ; This switch causes the command line that was used to create an
1660 ; object file to be recorded into the object file. The exact format
1661 ; of this recording is target and binary file format dependent.
1662 ; It is related to the -fverbose-asm switch, but that switch only
1663 ; records information in the assembler output file as comments, so
1664 ; they never reach the object file.
1665 frecord-gcc-switches
1666 Common Report Var(flag_record_gcc_switches)
1667 Record gcc command line switches in the object file.
1670 Common Report Var(flag_pcc_struct_return,0) Optimization
1671 Return small aggregates in registers
1674 Common Report Var(flag_regmove) Optimization
1675 Enables a register move optimization
1678 Common Report Var(flag_rename_registers) Init(2) Optimization
1679 Perform a register renaming optimization pass
1682 Common Report Var(flag_reorder_blocks) Optimization
1683 Reorder basic blocks to improve code placement
1685 freorder-blocks-and-partition
1686 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1687 Reorder basic blocks and partition into hot and cold sections
1690 Common Report Var(flag_reorder_functions) Optimization
1691 Reorder functions to improve code placement
1693 frerun-cse-after-loop
1694 Common Report Var(flag_rerun_cse_after_loop) Optimization
1695 Add a common subexpression elimination pass after loop optimizations
1699 Does nothing. Preserved for backward compatibility.
1702 Common Report Var(flag_rounding_math) Optimization SetByCombined
1703 Disable optimizations that assume default FP rounding behavior
1706 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1707 Enable scheduling across basic blocks
1710 Common Report Var(flag_sched_pressure) Init(0) Optimization
1711 Enable register pressure sensitive insn scheduling
1714 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1715 Allow speculative motion of non-loads
1718 Common Report Var(flag_schedule_speculative_load) Optimization
1719 Allow speculative motion of some loads
1721 fsched-spec-load-dangerous
1722 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1723 Allow speculative motion of more loads
1726 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1727 -fsched-verbose=<number> Set the verbosity level of the scheduler
1729 fsched2-use-superblocks
1730 Common Report Var(flag_sched2_use_superblocks) Optimization
1731 If scheduling post reload, do superblock scheduling
1735 Does nothing. Preserved for backward compatibility.
1738 Common Report Var(flag_schedule_insns) Optimization
1739 Reschedule instructions before register allocation
1742 Common Report Var(flag_schedule_insns_after_reload) Optimization
1743 Reschedule instructions after register allocation
1745 ; This flag should be on when a target implements non-trivial
1746 ; scheduling hooks, maybe saving some information for its own sake.
1747 ; On IA64, for example, this is used for correct bundling.
1748 fselective-scheduling
1749 Common Report Var(flag_selective_scheduling) Optimization
1750 Schedule instructions using selective scheduling algorithm
1752 fselective-scheduling2
1753 Common Report Var(flag_selective_scheduling2) Optimization
1754 Run selective scheduling after reload
1756 fsel-sched-pipelining
1757 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1758 Perform software pipelining of inner loops during selective scheduling
1760 fsel-sched-pipelining-outer-loops
1761 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1762 Perform software pipelining of outer loops during selective scheduling
1764 fsel-sched-reschedule-pipelined
1765 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1766 Reschedule pipelined regions without pipelining
1768 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1769 ; of stalled insns into the ready list.
1770 fsched-stalled-insns
1771 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1772 Allow premature scheduling of queued insns
1774 fsched-stalled-insns=
1775 Common RejectNegative Joined UInteger
1776 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1778 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1779 ; be examined for a dependency on a stalled insn that is candidate for
1780 ; premature removal from the queue of stalled insns into the ready list (has
1781 ; an effect only if the flag 'sched_stalled_insns' is set).
1782 fsched-stalled-insns-dep
1783 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1784 Set dependence distance checking in premature scheduling of queued insns
1786 fsched-stalled-insns-dep=
1787 Common RejectNegative Joined UInteger
1788 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1790 fsched-group-heuristic
1791 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1792 Enable the group heuristic in the scheduler
1794 fsched-critical-path-heuristic
1795 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1796 Enable the critical path heuristic in the scheduler
1798 fsched-spec-insn-heuristic
1799 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1800 Enable the speculative instruction heuristic in the scheduler
1802 fsched-rank-heuristic
1803 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1804 Enable the rank heuristic in the scheduler
1806 fsched-last-insn-heuristic
1807 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1808 Enable the last instruction heuristic in the scheduler
1810 fsched-dep-count-heuristic
1811 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1812 Enable the dependent count heuristic in the scheduler
1815 Common Report Var(flag_section_anchors) Optimization
1816 Access data in the same section from shared anchor points
1820 Does nothing. Preserved for backward compatibility.
1824 Does nothing. Preserved for backward compatibility.
1827 Common Report Var(flag_ree) Init(0)
1828 Turn on Redundant Extensions Elimination pass.
1831 Common Report Var(flag_show_column) Init(1)
1832 Show column numbers in diagnostics, when available. Default on
1835 Common Report Var(flag_shrink_wrap) Optimization
1836 Emit function prologues only before parts of the function that need it,
1837 rather than at the top of the function.
1840 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1841 Disable optimizations observable by IEEE signaling NaNs
1844 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1845 Disable floating point optimizations that ignore the IEEE signedness of zero
1847 fsingle-precision-constant
1848 Common Report Var(flag_single_precision_constant) Optimization
1849 Convert floating point constants to single precision constants
1851 fsplit-ivs-in-unroller
1852 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1853 Split lifetimes of induction variables when loops are unrolled
1856 Common Report Var(flag_split_stack) Init(-1)
1857 Generate discontiguous stack frames
1860 Common Report Var(flag_split_wide_types) Optimization
1861 Split wide types into independent registers
1863 fvariable-expansion-in-unroller
1864 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1865 Apply variable expansion when loops are unrolled
1868 Common Report RejectNegative Joined
1869 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1872 Common Alias(fstack-check=, specific, no)
1873 Insert stack checking code into the program. Same as -fstack-check=specific
1876 Common Var(common_deferred_options) Defer
1878 fstack-limit-register=
1879 Common RejectNegative Joined Var(common_deferred_options) Defer
1880 -fstack-limit-register=<register> Trap if the stack goes past <register>
1882 fstack-limit-symbol=
1883 Common RejectNegative Joined Var(common_deferred_options) Defer
1884 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1887 Common Report Var(flag_stack_protect, 1)
1888 Use propolice as a stack protection method
1890 fstack-protector-all
1891 Common Report RejectNegative Var(flag_stack_protect, 2)
1892 Use a stack protection method for every function
1895 Common RejectNegative Var(flag_stack_usage)
1896 Output stack usage information on a per-function basis
1900 Does nothing. Preserved for backward compatibility.
1902 ; Nonzero if we should do (language-dependent) alias analysis.
1903 ; Typically, this analysis will assume that expressions of certain
1904 ; types do not alias expressions of certain other types. Only used
1905 ; if alias analysis (in general) is enabled.
1907 Common Report Var(flag_strict_aliasing) Optimization
1908 Assume strict aliasing rules apply
1911 Common Report Var(flag_strict_overflow)
1912 Treat signed overflow as undefined
1915 Common Report Var(flag_sync_libcalls) Init(1)
1916 Implement __atomic operations via libcalls to legacy __sync functions
1919 Common Report Var(flag_syntax_only)
1920 Check for syntax errors, then stop
1923 Common Report Var(flag_test_coverage)
1924 Create data files needed by \"gcov\"
1927 Common Report Var(flag_thread_jumps) Optimization
1928 Perform jump threading optimizations
1931 Common Report Var(time_report)
1932 Report the time taken by each compiler pass
1935 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1936 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1939 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1942 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1945 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1948 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1951 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1954 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1955 Reorder top level functions, variables, and asms
1958 Common Report Var(flag_tracer)
1959 Perform superblock formation via tail duplication
1961 ; Zero means that floating-point math operations cannot generate a
1962 ; (user-visible) trap. This is the case, for example, in nonstop
1963 ; IEEE 754 arithmetic.
1965 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1966 Assume floating-point operations can trap
1969 Common Report Var(flag_trapv) Optimization
1970 Trap for signed overflow in addition, subtraction and multiplication
1973 Common Report Var(flag_tree_ccp) Optimization
1974 Enable SSA-CCP optimization on trees
1977 Common Report Var(flag_tree_bit_ccp) Optimization
1978 Enable SSA-BIT-CCP optimization on trees
1982 Does nothing. Preserved for backward compatibility.
1985 Common Report Var(flag_tree_ch) Optimization
1986 Enable loop header copying on trees
1988 ftree-coalesce-inlined-vars
1989 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
1990 Enable coalescing of copy-related user variables that are inlined
1993 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
1994 Enable coalescing of all copy-related user variables
1997 Common Report Var(flag_tree_copyrename) Optimization
1998 Replace SSA temporaries with better names in copies
2001 Common Report Var(flag_tree_copy_prop) Optimization
2002 Enable copy propagation on trees
2004 ftree-store-copy-prop
2006 Does nothing. Preserved for backward compatibility.
2009 Common Report Var(flag_tree_cselim) Init(2) Optimization
2010 Transform condition stores into unconditional ones
2012 ftree-switch-conversion
2013 Common Report Var(flag_tree_switch_conversion) Optimization
2014 Perform conversions of switch initializations.
2017 Common Report Var(flag_tree_dce) Optimization
2018 Enable SSA dead code elimination optimization on trees
2020 ftree-dominator-opts
2021 Common Report Var(flag_tree_dom) Optimization
2022 Enable dominator optimizations
2025 Common Report Var(flag_tree_tail_merge) Optimization
2026 Enable tail merging on trees
2029 Common Report Var(flag_tree_dse) Optimization
2030 Enable dead store elimination
2033 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2034 Enable forward propagation on trees
2037 Common Report Var(flag_tree_fre) Optimization
2038 Enable Full Redundancy Elimination (FRE) on trees
2041 Common Report Var(flag_optimize_strlen) Optimization
2042 Enable string length optimizations on trees
2044 ftree-loop-distribution
2045 Common Report Var(flag_tree_loop_distribution) Optimization
2046 Enable loop distribution on trees
2048 ftree-loop-distribute-patterns
2049 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2050 Enable loop distribution for patterns transformed into a library call
2053 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2054 Enable loop invariant motion on trees
2057 Common Alias(floop-interchange)
2058 Enable loop interchange transforms. Same as -floop-interchange
2061 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2062 Create canonical induction variables in loops
2065 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2066 Enable loop optimizations on tree level
2068 ftree-parallelize-loops=
2069 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2070 Enable automatic parallelization of loops
2073 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2074 Enable hoisting loads from conditional pointers.
2077 Common Report Var(flag_tree_pre) Optimization
2078 Enable SSA-PRE optimization on trees
2081 Common Report Var(flag_tree_partial_pre) Optimization
2082 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2085 Common Report Var(flag_tree_pta) Init(1) Optimization
2086 Perform function-local points-to analysis on trees.
2089 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2090 Enable reassociation on tree level
2094 Does nothing. Preserved for backward compatibility.
2097 Common Report Var(flag_tree_sink) Optimization
2098 Enable SSA code sinking on trees
2101 Common Report Var(flag_tree_slsr) Optimization
2102 Perform straight-line strength reduction
2105 Common Report Var(flag_tree_sra) Optimization
2106 Perform scalar replacement of aggregates
2109 Common Report Var(flag_tree_ter) Optimization
2110 Replace temporary expressions in the SSA->normal pass
2113 Common Report Var(flag_tree_live_range_split) Optimization
2114 Perform live range splitting during the SSA->normal pass
2117 Common Report Var(flag_tree_vrp) Init(0) Optimization
2118 Perform Value Range Propagation on trees
2121 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2122 Compile whole compilation unit at a time
2125 Common Report Var(flag_unroll_loops) Optimization
2126 Perform loop unrolling when iteration count is known
2129 Common Report Var(flag_unroll_all_loops) Optimization
2130 Perform loop unrolling for all loops
2132 ; Nonzero means that loop optimizer may assume that the induction variables
2133 ; that control loops do not overflow and that the loops with nontrivial
2134 ; exit condition are not infinite
2135 funsafe-loop-optimizations
2136 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2137 Allow loop optimizations to assume that the loops behave in normal way
2140 Common Report Var(flag_associative_math) SetByCombined
2141 Allow optimization for floating-point arithmetic which may change the
2142 result of the operation due to rounding.
2145 Common Report Var(flag_reciprocal_math) SetByCombined
2146 Same as -fassociative-math for expressions which include division.
2148 ; Nonzero means that unsafe floating-point math optimizations are allowed
2149 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2150 ; are allowed to assume that their arguments and results are "normal"
2151 ; (e.g., nonnegative for SQRT).
2152 funsafe-math-optimizations
2153 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2154 Allow math optimizations that may violate IEEE or ISO standards
2157 Common Report Var(flag_unswitch_loops) Optimization
2158 Perform loop unswitching
2161 Common Report Var(flag_unwind_tables) Optimization
2162 Just generate unwind tables for exception handling
2167 ; Positive if we should track variables, negative if we should run
2168 ; the var-tracking pass only to discard debug annotations, zero if
2169 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2170 ; will be set according to optimize, debug_info_level and debug_hooks
2171 ; in process_options ().
2173 Common Report Var(flag_var_tracking) Init(2) Optimization
2174 Perform variable tracking
2176 ; Positive if we should track variables at assignments, negative if
2177 ; we should run the var-tracking pass only to discard debug
2178 ; annotations. When flag_var_tracking_assignments ==
2179 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2180 fvar-tracking-assignments
2181 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2182 Perform variable tracking by annotating assignments
2184 ; Nonzero if we should toggle flag_var_tracking_assignments after
2185 ; processing options and computing its default. */
2186 fvar-tracking-assignments-toggle
2187 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2188 Toggle -fvar-tracking-assignments
2190 fvar-tracking-uninit
2191 Common Report Var(flag_var_tracking_uninit) Optimization
2192 Perform variable tracking and also tag variables that are uninitialized
2195 Common Report Var(flag_tree_vectorize) Optimization
2196 Enable loop vectorization on trees
2199 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2200 Enable basic block vectorization (SLP) on trees
2203 Common Report Var(flag_vect_cost_model) Optimization
2204 Enable use of cost model in vectorization
2206 ftree-vect-loop-version
2207 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2208 Enable loop versioning when doing loop vectorization on trees
2210 ftree-vectorizer-verbose=
2211 Common RejectNegative Joined UInteger
2212 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
2215 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2216 Enable copy propagation of scalar-evolution information.
2218 ; -fverbose-asm causes extra commentary information to be produced in
2219 ; the generated assembly code (to make it more readable). This option
2220 ; is generally only of use to those who actually need to read the
2221 ; generated assembly code (perhaps while debugging the compiler itself).
2222 ; -fno-verbose-asm, the default, causes the extra information
2223 ; to not be added and is useful when comparing two assembler files.
2225 Common Report Var(flag_verbose_asm)
2226 Add extra commentary to assembler output
2229 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2230 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2233 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2236 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2239 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2242 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2245 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2248 Common Report Var(flag_value_profile_transformations) Optimization
2249 Use expression value profiles in optimizations
2252 Common Report Var(flag_web) Init(2) Optimization
2253 Construct webs and split unrelated uses of single variable
2255 ftree-builtin-call-dce
2256 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2257 Enable conditional dead code elimination for builtin calls
2260 Common Report Var(flag_whole_program) Init(0) Optimization
2261 Perform whole program optimizations
2264 Common Report Var(flag_wrapv) Optimization
2265 Assume signed arithmetic overflow wraps around
2267 fzero-initialized-in-bss
2268 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2269 Put zero initialized data in the bss section
2272 Common JoinedOrMissing
2273 Generate debug information in default format
2276 Common JoinedOrMissing Negative(gdwarf-)
2277 Generate debug information in COFF format
2280 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2281 Generate debug information in DWARF v2 (or later) format
2284 Common JoinedOrMissing
2285 Generate debug information in default extended format
2288 Common RejectNegative Var(debug_generate_pub_sections, 0) Init(-1)
2289 Don't generate DWARF pubnames and pubtypes sections.
2292 Common RejectNegative Var(debug_generate_pub_sections, 1)
2293 Generate DWARF pubnames and pubtypes sections.
2295 gno-record-gcc-switches
2296 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2297 Don't record gcc command line switches in DWARF DW_AT_producer.
2299 grecord-gcc-switches
2300 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2301 Record gcc command line switches in DWARF DW_AT_producer.
2304 Common JoinedOrMissing Negative(gstabs+)
2305 Generate debug information in STABS format
2308 Common JoinedOrMissing Negative(gvms)
2309 Generate debug information in extended STABS format
2312 Common RejectNegative Var(dwarf_strict,0) Init(0)
2313 Emit DWARF additions beyond selected version
2316 Common Report RejectNegative Var(dwarf_strict,1)
2317 Don't emit DWARF additions beyond selected version
2320 Common Report Var(flag_gtoggle)
2321 Toggle debug information generation
2324 Common JoinedOrMissing Negative(gxcoff)
2325 Generate debug information in VMS format
2328 Common JoinedOrMissing Negative(gxcoff+)
2329 Generate debug information in XCOFF format
2332 Common JoinedOrMissing Negative(gcoff)
2333 Generate debug information in extended XCOFF format
2336 Driver Joined Separate
2339 Common Joined Var(plugindir_string) Init(0)
2340 -iplugindir=<dir> Set <dir> to be the default plugin directory
2343 Driver Joined Separate
2348 no-canonical-prefixes
2361 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2362 -o <file> Place output into <file>
2365 Common Var(profile_flag)
2366 Enable function profiling
2369 Driver Var(pass_exit_codes)
2372 Common Alias(Wpedantic)
2375 Common Var(flag_pedantic_errors)
2376 Like -pedantic but issue them as errors
2382 Driver Var(use_pipes)
2385 Driver JoinedOrMissing Var(print_file_name)
2387 print-libgcc-file-name
2390 print-multi-directory
2391 Driver Var(print_multi_directory)
2394 Driver Var(print_multi_lib)
2396 print-multi-os-directory
2397 Driver Var(print_multi_os_directory)
2400 Driver JoinedOrMissing Var(print_prog_name)
2403 Driver Var(print_search_dirs)
2406 Driver Var(print_sysroot)
2408 print-sysroot-headers-suffix
2409 Driver Var(print_sysroot_headers_suffix)
2412 Common Var(quiet_flag) RejectDriver
2413 Do not display functions compiled or elapsed time
2431 Driver Var(report_times)
2434 Driver JoinedOrMissing
2437 Driver Joined Separate
2441 ; C option, but driver must not handle as "-u ndef".
2444 Common Driver Var(verbose_flag)
2445 Enable verbose output
2448 Common Var(version_flag) RejectDriver
2449 Display the compiler's version
2452 Common Var(inhibit_warnings)
2456 Driver Separate Var(wrapper_string)
2459 Driver Joined Separate
2462 Driver RejectNegative Negative(pie)
2463 Create a shared library
2469 Driver Separate Alias(specs=)
2482 ; Documented for Fortran, but always accepted by driver.
2489 ; Documented for Go, but always accepted by driver.
2495 Driver RejectNegative Negative(shared)
2496 Create a position independent executable
2499 Driver Joined Separate
2501 ; This comment is to ensure we retain the blank line above.