1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
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.
35 ; Not used directly to control optimizations, only to save -Ofast
36 ; setting for "optimize" attributes.
40 ; 0 means straightforward implementation of complex divide acceptable.
41 ; 1 means wide ranges of inputs must work for complex divide.
42 ; 2 means C99-like requirements for complex multiply and divide.
44 int flag_complex_method = 1
46 ; Nonzero if subexpressions must be evaluated from left-to-right.
48 int flag_evaluation_order = 0
50 ; Language specific warning pass for unused results.
52 bool flag_warn_unused_result = false
57 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
61 ; True to warn about any objects definitions whose size is larger
62 ; than N bytes. Also want about function definitions whose returned
63 ; values are larger than N bytes, where N is 'larger_than_size'.
68 HOST_WIDE_INT larger_than_size
70 ; True to warn about any function whose frame size is larger
73 bool warn_frame_larger_than
76 HOST_WIDE_INT frame_larger_than_size
78 ; Nonzero means we should be saving declaration info into a .X file.
80 int flag_gen_aux_info = 0
82 ; Nonzero if we are compiling code for a shared library, zero for
87 ; These two are really VEC(char_p,heap) *.
90 void *flag_instrument_functions_exclude_functions
93 void *flag_instrument_functions_exclude_files
95 ; Generic structs (e.g. templates not explicitly specialized)
96 ; may not have a compilation unit associated with them, and so
97 ; may need to be treated differently from ordinary structs.
99 ; Structs only handled by reference (indirectly), will also usually
100 ; not need as much debugging information.
103 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
106 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
108 ; True if we should exit after parsing options.
110 bool exit_after_options
112 ; Type(s) of debugging information we are producing (if any). See
113 ; flag-types.h for the definitions of the different possible types of
114 ; debugging information.
116 enum debug_info_type write_symbols = NO_DEBUG
118 ; Level of debugging information we are producing. See flag-types.h
119 ; for the definitions of the different possible levels.
121 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
123 ; Nonzero means use GNU-only extensions in the generated symbolic
124 ; debugging information. Currently, this only has an effect when
125 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
127 bool use_gnu_debug_info_extensions
129 ; Original value of maximum field alignment in bytes, specified via
130 ; -fpack-struct=<value>.
132 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
135 enum vect_verbosity_levels user_vect_verbosity_level = MAX_VERBOSITY_LEVEL
137 ; Type of stack check.
139 enum stack_check_type flag_stack_check = NO_STACK_CHECK
141 ; -dA causes debug commentary information to be produced in
142 ; the generated assembly code (to make it more readable). This option
143 ; is generally only of use to those who actually need to read the
144 ; generated assembly code (perhaps while debugging the compiler itself).
145 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
146 ; to be a catchall for printing debug information in the assembler file.
150 ; -dP causes the rtl to be emitted as a comment in assembly.
152 int flag_dump_rtl_in_asm
154 ; Whether -da was passed (used only in handle_common_deferred_options).
156 bool flag_dump_all_passed
158 ; Other flags saying which kinds of debugging dump have been requested.
161 int rtl_dump_and_exit
164 int flag_print_asm_name
167 enum graph_dump_types graph_dump_format = no_graph
169 ; Name of top-level original source file (what was input to cpp).
170 ; This comes from the #-command at the beginning of the actual input.
171 ; If there isn't any there, then this is the cc1 input file name.
173 const char *main_input_filename
175 ; Pointer to base name in main_input_filename, with directories and a
176 ; single final extension removed, and the length of this base
180 const char *main_input_basename
183 int main_input_baselength
185 ; Which options have been printed by --help.
189 ; Which enums have been printed by --help. 0 = not printed, no
190 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
193 char *help_enum_printed
195 ; The number of columns for --help output.
197 unsigned int help_columns
199 ; Whether this options structure has been through finish_options
201 bool flag_opts_finished
213 Driver Alias(coverage)
219 Common Separate Alias(d)
222 Common Joined Alias(d)
225 Common Separate Alias(dumpbase)
228 Common Separate Alias(dumpdir)
231 Driver Separate Alias(e)
234 Driver Joined Alias(e)
237 Common Warning Alias(Wextra)
240 Driver Separate Alias(Xassembler)
243 Driver JoinedOrMissing Alias(Xassembler)
246 Driver Separate Alias(Xlinker)
249 Driver JoinedOrMissing Alias(Xlinker)
252 Driver Separate Alias(u)
255 Driver Joined Alias(u)
258 Common Driver Var(help_flag)
259 Display this information
262 Common Driver Report Joined
263 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
266 Driver Separate Alias(x)
269 Driver Joined Alias(x)
272 Driver Separate Alias(L)
275 Driver Joined Alias(L)
277 -no-canonical-prefixes
278 Driver Alias(no-canonical-prefixes)
280 -no-standard-libraries
281 Driver Alias(nostdlib)
290 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
293 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
296 Driver Alias(pass-exit-codes)
299 Common Alias(pedantic)
302 Common Alias(pedantic-errors)
311 Driver Separate Alias(B)
314 Driver JoinedOrMissing Alias(B)
320 Driver Separate Alias(print-file-name=)
323 Driver JoinedOrMissing Alias(print-file-name=)
325 -print-libgcc-file-name
326 Driver Alias(print-libgcc-file-name)
328 -print-multi-directory
329 Driver Alias(print-multi-directory)
332 Driver Alias(print-multi-lib)
334 -print-multi-os-directory
335 Driver Alias(print-multi-os-directory)
338 Driver Alias(print-multiarch)
341 Driver Separate Alias(print-prog-name=)
344 Driver JoinedOrMissing Alias(print-prog-name=)
347 Driver Alias(print-search-dirs)
350 Driver Alias(print-sysroot)
352 -print-sysroot-headers-suffix
353 Driver Alias(print-sysroot-headers-suffix)
359 Driver Alias(save-temps)
365 Driver Separate Alias(specs=)
368 Driver Joined Alias(specs=)
374 Driver Alias(symbolic)
378 Alias for --help=target
386 ;; The driver used to convert options such as --help into forms such
387 ;; as -fhelp; the following four entries are for compatibility with
388 ;; any direct uses of those (undocumented) -f forms
390 Common Driver Alias(-help)
393 Common Driver Joined Alias(-help=)
396 Common Driver Alias(-target-help)
399 Common Driver Alias(-version)
403 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
406 Common Joined Alias(-param)
409 Driver Separate Alias(-sysroot=)
412 Driver JoinedOrMissing
418 Driver Joined Separate
424 Driver Joined Separate
430 Common JoinedOrMissing Optimization
431 -O<number> Set optimization level to <number>
435 Optimize for space rather than speed
439 Optimize for speed disregarding exact standards compliance
451 Driver Joined Separate
457 Driver Joined Separate
478 Common RejectNegative Warning Alias(Wextra)
479 This switch is deprecated; use -Wextra instead
482 Driver JoinedOrMissing
485 Driver JoinedOrMissing
488 Driver JoinedOrMissing
491 Common Var(warn_aggregate_return) Warning
492 Warn about returning structures, unions or arrays
495 Common Var(warn_array_bounds) Warning
496 Warn if an array is accessed out of bounds
499 Common Var(warn_attributes) Init(1) Warning
500 Warn about inappropriate attribute usage
503 Common Var(warn_cast_align) Warning
504 Warn about pointer casts which increase alignment
507 Common Var(warn_cpp) Init(1) Warning
508 Warn when a #warning directive is encountered
510 Wdeprecated-declarations
511 Common Var(warn_deprecated_decl) Init(1) Warning
512 Warn about uses of __attribute__((deprecated)) declarations
514 Wdisabled-optimization
515 Common Var(warn_disabled_optimization) Warning
516 Warn when an optimization pass is disabled
519 Common Var(warnings_are_errors)
520 Treat all warnings as errors
524 Treat specified warning as error
527 Common Var(extra_warnings) Warning
528 Print extra (possibly unwanted) warnings
531 Common Var(flag_fatal_errors)
532 Exit on the first error occurred
535 Common RejectNegative Joined UInteger
536 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
539 Common Var(warn_inline) Warning
540 Warn when an inlined function cannot be inlined
543 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
546 Common RejectNegative Joined UInteger Warning
547 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
549 Wunsafe-loop-optimizations
550 Common Var(warn_unsafe_loop_optimizations) Warning
551 Warn if the loop cannot be optimized due to nontrivial assumptions.
554 Common Var(warn_missing_noreturn) Warning
555 Warn about functions which might be candidates for __attribute__((noreturn))
558 Common Var(warn_mudflap) Init(1) Warning
559 Warn about constructs not instrumented by -fmudflap
562 Common Var(warn_overflow) Init(1) Warning
563 Warn about overflow in arithmetic expressions
566 Common Var(warn_packed) Warning
567 Warn when the packed attribute has no effect on struct layout
570 Common Var(warn_padded) Warning
571 Warn when padding is required to align structure members
574 Common Var(warn_shadow) Warning
575 Warn when one local variable shadows another
578 Common Var(warn_stack_protect) Warning
579 Warn when not issuing stack smashing protection for some reason
583 Warn about code which might break strict aliasing rules
586 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
587 Warn about code which might break strict aliasing rules
591 Warn about optimizations that assume that signed overflow is undefined
594 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
595 Warn about optimizations that assume that signed overflow is undefined
597 Wsuggest-attribute=const
598 Common Var(warn_suggest_attribute_const) Warning
599 Warn about functions which might be candidates for __attribute__((const))
601 Wsuggest-attribute=pure
602 Common Var(warn_suggest_attribute_pure) Warning
603 Warn about functions which might be candidates for __attribute__((pure))
605 Wsuggest-attribute=noreturn
606 Common Var(warn_suggest_attribute_noreturn) Warning
607 Warn about functions which might be candidates for __attribute__((noreturn))
610 Common Var(warn_switch) Warning
611 Warn about enumerated switches, with no default, missing a case
614 Common Var(warn_switch_default) Warning
615 Warn about enumerated switches missing a \"default:\" statement
618 Common Var(warn_switch_enum) Warning
619 Warn about all enumerated switches missing a specific case
622 Common Var(warn_system_headers) Warning
623 Do not suppress warnings from system headers
626 Common Var(warn_trampolines) Warning
627 Warn whenever a trampoline is generated
630 Common Var(warn_type_limits) Init(-1) Warning
631 Warn if a comparison is always true or always false due to the limited range of the data type
634 Common Var(warn_uninitialized) Init(-1) Warning
635 Warn about uninitialized automatic variables
639 Does nothing. Preserved for backward compatibility.
642 Common Var(warn_unused) Init(0) Warning
643 Enable all -Wunused- warnings
645 Wunused-but-set-parameter
646 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
647 Warn when a function parameter is only set, otherwise unused
649 Wunused-but-set-variable
650 Common Var(warn_unused_but_set_variable) Init(-1) Warning
651 Warn when a variable is only set, otherwise unused
654 Common Var(warn_unused_function) Init(-1) Warning
655 Warn when a function is unused
658 Common Var(warn_unused_label) Init(-1) Warning
659 Warn when a label is unused
662 Common Var(warn_unused_parameter) Init(-1) Warning
663 Warn when a function parameter is unused
666 Common Var(warn_unused_value) Init(-1) Warning
667 Warn when an expression value is unused
670 Common Var(warn_unused_variable) Init(-1) Warning
671 Warn when a variable is unused
674 Common Var(warn_coverage_mismatch) Init(1) Warning
675 Warn in case profiles in -fprofile-use do not match
690 Common Separate Var(aux_info_file_name)
691 -aux-info <file> Emit declaration information into <file>
694 Common Joined Alias(aux-info)
697 Common Separate RejectDriver Var(aux_base_name)
700 Common Separate RejectDriver
710 -d<letters> Enable dumps from specific passes of the compiler
713 Common Separate Var(dump_base_name)
714 -dumpbase <file> Set the file basename to be used for dumps
717 Common Separate Var(dump_dir_name)
718 -dumpdir <dir> Set the directory name to be used for dumps
730 Driver Joined Separate
732 ; This option has historically been passed down to the linker by an
733 ; accident of a %{e*} spec, so ensure it continues to be passed down
734 ; as a single option. The supported option for this purpose is
735 ; -rdynamic. See PR 47390.
739 ; The version of the C++ ABI in use. The following values are allowed:
741 ; 0: The version of the ABI believed most conformant with the C++ ABI
742 ; specification. This ABI may change as bugs are discovered and fixed.
743 ; Therefore, 0 will not necessarily indicate the same ABI in different
746 ; 1: The version of the ABI first used in G++ 3.2.
748 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
750 ; 3: The version of the ABI that fixes the missing underscore
751 ; in template non-type arguments of pointer type.
753 ; 4: The version of the ABI that introduces unambiguous mangling of
754 ; vector types. First selectable in G++ 4.5.
756 ; 5: The version of the ABI that ignores attribute const/noreturn
757 ; in function pointer mangling, and corrects mangling of decltype and
758 ; function parameters used in other parameters and the return type.
759 ; First selectable in G++ 4.6.
761 ; Additional positive integers will be assigned as new versions of
762 ; the ABI become the default version of the ABI.
764 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
767 Common Report Var(align_functions,0) Optimization UInteger
768 Align the start of functions
771 Common RejectNegative Joined UInteger Var(align_functions)
774 Common Report Var(align_jumps,0) Optimization UInteger
775 Align labels which are only reached by jumping
778 Common RejectNegative Joined UInteger Var(align_jumps)
781 Common Report Var(align_labels,0) Optimization UInteger
785 Common RejectNegative Joined UInteger Var(align_labels)
788 Common Report Var(align_loops,0) Optimization UInteger
789 Align the start of loops
792 Common RejectNegative Joined UInteger Var(align_loops)
796 Does nothing. Preserved for backward compatibility.
800 Does nothing. Preserved for backward compatibility.
802 fargument-noalias-global
804 Does nothing. Preserved for backward compatibility.
806 fargument-noalias-anything
808 Does nothing. Preserved for backward compatibility.
810 fasynchronous-unwind-tables
811 Common Report Var(flag_asynchronous_unwind_tables) Optimization
812 Generate unwind tables that are exact at each instruction boundary
815 Common Report Var(flag_auto_inc_dec) Init(1)
816 Generate auto-inc/dec instructions
818 ; -fcheck-bounds causes gcc to generate array bounds checks.
819 ; For C, C++ and ObjC: defaults off.
820 ; For Java: defaults to on.
821 ; For Fortran: defaults to off.
823 Common Report Var(flag_bounds_check)
824 Generate code to check bounds before indexing arrays
827 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
828 Replace add, compare, branch with branch on count register
830 fbranch-probabilities
831 Common Report Var(flag_branch_probabilities) Optimization
832 Use profiling information for branch probabilities
834 fbranch-target-load-optimize
835 Common Report Var(flag_branch_target_load_optimize) Optimization
836 Perform branch target load optimization before prologue / epilogue threading
838 fbranch-target-load-optimize2
839 Common Report Var(flag_branch_target_load_optimize2) Optimization
840 Perform branch target load optimization after prologue / epilogue threading
843 Common Report Var(flag_btr_bb_exclusive) Optimization
844 Restrict target load migration not to re-use registers in any basic block
847 Common Joined RejectNegative Var(common_deferred_options) Defer
848 -fcall-saved-<register> Mark <register> as being preserved across functions
851 Common Joined RejectNegative Var(common_deferred_options) Defer
852 -fcall-used-<register> Mark <register> as being corrupted by function calls
854 ; Nonzero for -fcaller-saves: allocate values in regs that need to
855 ; be saved across function calls, if that produces overall better code.
856 ; Optional now, so people can test it.
858 Common Report Var(flag_caller_saves) Optimization
859 Save registers around function calls
862 Common Report Var(flag_check_data_deps)
863 Compare the results of several data dependence analyzers.
865 fcombine-stack-adjustments
866 Common Report Var(flag_combine_stack_adjustments) Optimization
867 Looks for opportunities to reduce stack adjustments and stack references.
870 Common Report Var(flag_no_common,0) Optimization
871 Do not put uninitialized globals in the common section
875 ; Converted by the driver to -fcompare-debug= options.
878 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
879 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
881 fcompare-debug-second
882 Common Driver RejectNegative Var(flag_compare_debug)
883 Run only the second compilation of -fcompare-debug
886 Common Report Var(flag_compare_elim_after_reload) Optimization
887 Perform comparison elimination after register allocation has finished
890 Common Var(flag_conserve_stack) Optimization
891 Do not perform optimizations increasing noticeably stack usage
894 Common Report Var(flag_cprop_registers) Optimization
895 Perform a register copy-propagation optimization pass
898 Common Report Var(flag_crossjumping) Optimization
899 Perform cross-jumping optimization
902 Common Report Var(flag_cse_follow_jumps) Optimization
903 When running CSE, follow jumps to their targets
907 Does nothing. Preserved for backward compatibility.
910 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
911 Omit range reduction step when performing complex division
914 Common Report Var(flag_cx_fortran_rules) Optimization
915 Complex multiplication and division follow Fortran rules
918 Common Report Var(flag_data_sections) Optimization
919 Place data items into their own section
922 Common Report Var(common_deferred_options) Defer
923 List all available debugging counters with their limits and counts.
926 Common RejectNegative Joined Var(common_deferred_options) Defer
927 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
930 Common Joined RejectNegative Var(common_deferred_options) Defer
931 Map one directory name to another in debug information
933 ; Nonzero for -fdefer-pop: don't pop args after each function call
934 ; instead save them up to pop many calls' args with one insns.
936 Common Report Var(flag_defer_pop) Optimization
937 Defer popping functions args from stack until later
940 Common Report Var(flag_delayed_branch) Optimization
941 Attempt to fill delay slots of branch instructions
943 fdelete-null-pointer-checks
944 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
945 Delete useless null pointer checks
948 Common Report Var(flag_devirtualize) Optimization
949 Try to convert virtual calls to direct ones.
951 fdiagnostics-show-location=
952 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
953 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
955 ; Required for these enum values.
960 Name(diagnostic_prefixing_rule) Type(int)
963 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
966 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
968 fdiagnostics-show-option
969 Common Var(flag_diagnostics_show_option) Init(1)
970 Amend appropriate diagnostic messages with the command line option that controls them
973 Common Joined RejectNegative Var(common_deferred_options) Defer
974 -fdump-<type> Dump various compiler internals to a file
977 Driver RejectNegative
980 Common RejectNegative Joined Var(flag_dump_final_insns)
981 -fdump-final-insns=filename Dump to filename the insns at the end of translation
984 Common RejectNegative Joined Var(flag_dump_go_spec)
985 -fdump-go-spec=filename Write all declarations to file as Go code
988 Common Report Var(flag_dump_noaddr)
989 Suppress output of addresses in debugging dumps
992 Common Report Var(flag_dump_unnumbered)
993 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
995 fdump-unnumbered-links
996 Common Report Var(flag_dump_unnumbered_links)
997 Suppress output of previous and next insn numbers in debugging dumps
1000 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1001 Enable CFI tables via GAS assembler directives.
1004 Common Report Var(flag_early_inlining) Init(1) Optimization
1005 Perform early inlining
1007 feliminate-dwarf2-dups
1008 Common Report Var(flag_eliminate_dwarf2_dups)
1009 Perform DWARF2 duplicate elimination
1012 Common Report Var(flag_ipa_sra) Init(0) Optimization
1013 Perform interprocedural reduction of aggregates
1015 feliminate-unused-debug-symbols
1016 Common Report Var(flag_debug_only_used_symbols)
1017 Perform unused type elimination in debug info
1019 feliminate-unused-debug-types
1020 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1021 Perform unused type elimination in debug info
1023 femit-class-debug-always
1024 Common Report Var(flag_emit_class_debug_always) Init(0)
1025 Do not suppress C++ class debug information.
1028 Common Report Var(flag_enable_icf_debug)
1029 Generate debug information to support Identical Code Folding (ICF)
1032 Common Report Var(flag_exceptions) Optimization
1033 Enable exception handling
1035 fexpensive-optimizations
1036 Common Report Var(flag_expensive_optimizations) Optimization
1037 Perform a number of minor, expensive optimizations
1040 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1041 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1044 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1047 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1050 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1056 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1057 Assume no NaNs or infinities are generated
1060 Common Joined RejectNegative Var(common_deferred_options) Defer
1061 -ffixed-<register> Mark <register> as being unavailable to the compiler
1064 Common Report Var(flag_float_store) Optimization
1065 Don't allocate floats and doubles in extended-precision registers
1069 Does nothing. Preserved for backward compatibility.
1072 Common Report Var(flag_forward_propagate) Optimization
1073 Perform a forward propagation pass on RTL
1076 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1077 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1080 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1083 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1085 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1087 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1090 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1092 ; Nonzero means don't put addresses of constant functions in registers.
1093 ; Used for compiling the Unix kernel, where strange substitutions are
1094 ; done on the assembly output.
1096 Common Report Var(flag_no_function_cse,0)
1097 Allow function addresses to be held in registers
1100 Common Report Var(flag_function_sections)
1101 Place each function into its own section
1104 Common Report Var(flag_gcse) Optimization
1105 Perform global common subexpression elimination
1108 Common Report Var(flag_gcse_lm) Init(1) Optimization
1109 Perform enhanced load motion during global common subexpression elimination
1112 Common Report Var(flag_gcse_sm) Init(0) Optimization
1113 Perform store motion after global common subexpression elimination
1116 Common Report Var(flag_gcse_las) Init(0) Optimization
1117 Perform redundant load after store elimination in global common subexpression
1121 Common Report Var(flag_gcse_after_reload) Optimization
1122 Perform global common subexpression elimination after register allocation
1125 ; This option is not documented yet as its semantics will change.
1127 Common Report Var(flag_graphite)
1128 Enable in and out of Graphite representation
1131 Common Report Var(flag_graphite_identity) Optimization
1132 Enable Graphite Identity transformation
1134 floop-parallelize-all
1135 Common Report Var(flag_loop_parallelize_all) Optimization
1136 Mark all loops as parallel
1139 Common Report Var(flag_loop_strip_mine) Optimization
1140 Enable Loop Strip Mining transformation
1143 Common Report Var(flag_loop_interchange) Optimization
1144 Enable Loop Interchange transformation
1147 Common Report Var(flag_loop_block) Optimization
1148 Enable Loop Blocking transformation
1151 Common Report Var(flag_loop_flatten) Optimization
1152 Enable Loop Flattening transformation
1154 fstrict-volatile-bitfields
1155 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1156 Force bitfield accesses to match their type width
1158 fguess-branch-probability
1159 Common Report Var(flag_guess_branch_prob) Optimization
1160 Enable guessing of branch probabilities
1162 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1163 ; Generate position-independent code for executables if possible
1164 ; On SVR4 targets, it also controls whether or not to emit a
1165 ; string identifying the compiler.
1167 Common Report Var(flag_no_ident,0)
1168 Process #ident directives
1171 Common Report Var(flag_if_conversion) Optimization
1172 Perform conversion of conditional jumps to branchless equivalents
1175 Common Report Var(flag_if_conversion2) Optimization
1176 Perform conversion of conditional jumps to conditional execution
1178 ftree-loop-if-convert
1179 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1180 Convert conditional jumps in innermost loops to branchless equivalents
1182 ftree-loop-if-convert-stores
1183 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1184 Also if-convert conditional jumps containing memory writes
1186 ; -finhibit-size-directive inhibits output of .size for ELF.
1187 ; This is used only for compiling crtstuff.c,
1188 ; and it may be extended to other effects
1189 ; needed for crtstuff.c on other systems.
1190 finhibit-size-directive
1191 Common Report Var(flag_inhibit_size_directive)
1192 Do not generate .size directives
1195 Common Report Var(flag_indirect_inlining)
1196 Perform indirect inlining
1198 ; Nonzero means that functions declared `inline' will be treated
1199 ; as `static'. Prevents generation of zillions of copies of unused
1200 ; static inline functions; instead, `inlines' are written out
1201 ; only when actually used. Used in conjunction with -g. Also
1202 ; does the right thing with #pragma interface.
1204 Common Report Var(flag_no_inline,0) Init(0)
1205 Pay attention to the \"inline\" keyword
1207 finline-small-functions
1208 Common Report Var(flag_inline_small_functions) Optimization
1209 Integrate simple functions into their callers when code size is known to not growth
1212 Common Report Var(flag_inline_functions) Optimization
1213 Integrate simple functions into their callers
1215 finline-functions-called-once
1216 Common Report Var(flag_inline_functions_called_once) Init(1) Optimization
1217 Integrate functions called once into their callers
1220 Common RejectNegative Joined Alias(finline-limit=)
1223 Common RejectNegative Joined UInteger
1224 -finline-limit=<number> Limit the size of inlined functions to <number>
1226 finstrument-functions
1227 Common Report Var(flag_instrument_function_entry_exit)
1228 Instrument function entry and exit with profiling calls
1230 finstrument-functions-exclude-function-list=
1231 Common RejectNegative Joined
1232 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1234 finstrument-functions-exclude-file-list=
1235 Common RejectNegative Joined
1236 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1239 Common Report Var(flag_ipa_cp) Optimization
1240 Perform Interprocedural constant propagation
1243 Common Report Var(flag_ipa_cp_clone) Optimization
1244 Perform cloning to make Interprocedural constant propagation stronger
1247 Common Report Var(flag_ipa_profile) Init(0) Optimization
1248 Perform interprocedural profile propagation
1251 Common Report Var(flag_ipa_pta) Init(0) Optimization
1252 Perform interprocedural points-to analysis
1255 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1256 Discover pure and const functions
1259 Common Report Var(flag_ipa_reference) Init(0) Optimization
1260 Discover readonly and non addressable static variables
1263 Common Report Var(flag_ipa_matrix_reorg) Optimization
1264 Perform matrix layout flattening and transposing based
1265 on profiling information.
1268 Common Report Var(flag_ipa_struct_reorg)
1269 Perform structure layout optimizations based
1270 on profiling information.
1273 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1274 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1277 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1280 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1283 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1286 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_MIXED)
1287 -fira-region=[one|all|mixed] Set regions for IRA
1290 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1293 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1296 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1299 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1302 Common Report Var(flag_ira_loop_pressure)
1303 Use IRA based register pressure calculation
1304 in RTL loop optimizations.
1306 fira-share-save-slots
1307 Common Report Var(flag_ira_share_save_slots) Init(1)
1308 Share slots for saving different hard registers.
1310 fira-share-spill-slots
1311 Common Report Var(flag_ira_share_spill_slots) Init(1)
1312 Share stack slots for spilled pseudo-registers.
1315 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1316 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1319 Common Report Var(flag_ivopts) Init(1) Optimization
1320 Optimize induction variables on trees
1323 Common Var(flag_jump_tables) Init(1) Optimization
1324 Use jump tables for sufficiently large switch statements
1326 fkeep-inline-functions
1327 Common Report Var(flag_keep_inline_functions)
1328 Generate code for functions even if they are fully inlined
1331 Common Report Var(flag_keep_static_consts) Init(1)
1332 Emit static const variables even if they are not used
1335 Common Report Var(flag_leading_underscore) Init(-1)
1336 Give external symbols a leading underscore
1340 Does nothing. Preserved for backward compatibility.
1344 Enable link-time optimization.
1347 Common RejectNegative Joined Var(flag_lto)
1348 Link-time optimization with number of parallel jobs or jobserver.
1351 Common Var(flag_lto_partition_1to1)
1352 Partition functions and vars at linktime based on object files they originate from
1354 flto-partition=balanced
1355 Common Var(flag_lto_partition_balanced)
1356 Partition functions and vars at linktime into approximately same sized buckets
1359 Common Var(flag_lto_partition_none)
1360 Disable partioning and streaming
1362 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1363 flto-compression-level=
1364 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1365 -flto-compression-level=<number> Use zlib compression level <number> for IL
1368 Common Report Var(flag_lto_report) Init(0) Optimization
1369 Report various link-time optimization statistics
1372 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1373 Set errno after built-in math functions
1376 Common Joined RejectNegative UInteger Var(flag_max_errors)
1377 -fmax-errors=<number> Maximum number of errors to report
1380 Common Report Var(mem_report)
1381 Report on permanent memory allocation
1383 ; This will attempt to merge constant section constants, if 1 only
1384 ; string constants and constants from constant pool, if 2 also constant
1386 fmerge-all-constants
1387 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1388 Attempt to merge identical constants and constant variables
1391 Common Report Var(flag_merge_constants,1) Optimization
1392 Attempt to merge identical constants across compilation units
1394 fmerge-debug-strings
1395 Common Report Var(flag_merge_debug_strings) Init(1)
1396 Attempt to merge identical debug strings across compilation units
1399 Common RejectNegative Joined UInteger
1400 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1403 Common Report Var(flag_modulo_sched) Optimization
1404 Perform SMS based modulo scheduling before the first scheduling pass
1406 fmodulo-sched-allow-regmoves
1407 Common Report Var(flag_modulo_sched_allow_regmoves)
1408 Perform SMS based modulo scheduling with register moves allowed
1410 fmove-loop-invariants
1411 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1412 Move loop invariant computations out of loops
1415 Common RejectNegative Report Var(flag_mudflap)
1416 Add mudflap bounds-checking instrumentation for single-threaded program
1419 Common RejectNegative Report Var(flag_mudflap,2)
1420 Add mudflap bounds-checking instrumentation for multi-threaded program
1423 Common RejectNegative Report Var(flag_mudflap_ignore_reads)
1424 Ignore read operations when inserting mudflap instrumentation
1427 Common Var(flag_dce) Init(1) Optimization
1428 Use the RTL dead code elimination pass
1431 Common Var(flag_dse) Init(1) Optimization
1432 Use the RTL dead store elimination pass
1434 freschedule-modulo-scheduled-loops
1435 Common Report Var(flag_resched_modulo_sched) Optimization
1436 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1438 fnon-call-exceptions
1439 Common Report Var(flag_non_call_exceptions) Optimization
1440 Support synchronous non-call exceptions
1443 Common Report Var(flag_omit_frame_pointer) Optimization
1444 When possible do not generate stack frames
1446 foptimize-register-move
1447 Common Report Var(flag_regmove) Optimization
1448 Do the full register move optimization pass
1450 foptimize-sibling-calls
1451 Common Report Var(flag_optimize_sibling_calls) Optimization
1452 Optimize sibling and tail recursive calls
1455 Common Report Var(flag_partial_inlining)
1456 Perform partial inlining
1459 Common Report Var(pre_ipa_mem_report)
1460 Report on memory allocation before interprocedural optimization
1462 fpost-ipa-mem-report
1463 Common Report Var(post_ipa_mem_report)
1464 Report on memory allocation before interprocedural optimization
1467 Common Report Var(flag_pack_struct) Optimization
1468 Pack structure members together without holes
1471 Common RejectNegative Joined UInteger Optimization
1472 -fpack-struct=<number> Set initial maximum structure member alignment
1475 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1476 Return small aggregates in memory, not registers
1479 Common Report Var(flag_peel_loops) Optimization
1480 Perform loop peeling
1483 Common Report Var(flag_no_peephole,0) Optimization
1484 Enable machine specific peephole optimizations
1487 Common Report Var(flag_peephole2) Optimization
1488 Enable an RTL peephole pass before sched2
1491 Common Report Var(flag_pic,2)
1492 Generate position-independent code if possible (large mode)
1495 Common Report Var(flag_pie,2)
1496 Generate position-independent code for executables if possible (large mode)
1499 Common Report Var(flag_pic,1)
1500 Generate position-independent code if possible (small mode)
1503 Common Report Var(flag_pie,1)
1504 Generate position-independent code for executables if possible (small mode)
1507 Common Joined RejectNegative Var(common_deferred_options) Defer
1508 Specify a plugin to load
1511 Common Joined RejectNegative Var(common_deferred_options) Defer
1512 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1514 fpredictive-commoning
1515 Common Report Var(flag_predictive_commoning) Optimization
1516 Run predictive commoning optimization.
1518 fprefetch-loop-arrays
1519 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1520 Generate prefetch instructions, if available, for arrays in loops
1523 Common Report Var(profile_flag)
1524 Enable basic program profiling code
1527 Common Report Var(profile_arc_flag)
1528 Insert arc-based program profiling code
1531 Common Joined RejectNegative Var(profile_data_prefix)
1532 Set the top-level directory for storing the profile data.
1533 The default is 'pwd'.
1536 Common Report Var(flag_profile_correction)
1537 Enable correction of flow inconsistent profile data input
1541 Enable common options for generating profile info for profile feedback directed optimizations
1544 Common Joined RejectNegative
1545 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1548 Common Var(flag_profile_use)
1549 Enable common options for performing profile feedback directed optimizations
1552 Common Joined RejectNegative
1553 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1556 Common Report Var(flag_profile_values)
1557 Insert code to profile values of expressions
1560 Common Var(common_deferred_options) Defer
1563 Common Joined RejectNegative Var(common_deferred_options) Defer
1564 -frandom-seed=<string> Make compile reproducible using <string>
1566 ; This switch causes the command line that was used to create an
1567 ; object file to be recorded into the object file. The exact format
1568 ; of this recording is target and binary file format dependent.
1569 ; It is related to the -fverbose-asm switch, but that switch only
1570 ; records information in the assembler output file as comments, so
1571 ; they never reach the object file.
1572 frecord-gcc-switches
1573 Common Report Var(flag_record_gcc_switches)
1574 Record gcc command line switches in the object file.
1577 Common Report Var(flag_pcc_struct_return,0) Optimization
1578 Return small aggregates in registers
1581 Common Report Var(flag_regmove) Optimization
1582 Enables a register move optimization
1585 Common Report Var(flag_rename_registers) Init(2) Optimization
1586 Perform a register renaming optimization pass
1589 Common Report Var(flag_reorder_blocks) Optimization
1590 Reorder basic blocks to improve code placement
1592 freorder-blocks-and-partition
1593 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1594 Reorder basic blocks and partition into hot and cold sections
1597 Common Report Var(flag_reorder_functions) Optimization
1598 Reorder functions to improve code placement
1600 frerun-cse-after-loop
1601 Common Report Var(flag_rerun_cse_after_loop) Optimization
1602 Add a common subexpression elimination pass after loop optimizations
1606 Does nothing. Preserved for backward compatibility.
1609 Common Report Var(flag_rounding_math) Optimization SetByCombined
1610 Disable optimizations that assume default FP rounding behavior
1613 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1614 Enable scheduling across basic blocks
1617 Common Report Var(flag_sched_pressure) Init(0) Optimization
1618 Enable register pressure sensitive insn scheduling
1621 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1622 Allow speculative motion of non-loads
1625 Common Report Var(flag_schedule_speculative_load) Optimization
1626 Allow speculative motion of some loads
1628 fsched-spec-load-dangerous
1629 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1630 Allow speculative motion of more loads
1633 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1634 -fsched-verbose=<number> Set the verbosity level of the scheduler
1636 fsched2-use-superblocks
1637 Common Report Var(flag_sched2_use_superblocks) Optimization
1638 If scheduling post reload, do superblock scheduling
1642 Does nothing. Preserved for backward compatibility.
1645 Common Report Var(flag_schedule_insns) Optimization
1646 Reschedule instructions before register allocation
1649 Common Report Var(flag_schedule_insns_after_reload) Optimization
1650 Reschedule instructions after register allocation
1652 ; This flag should be on when a target implements non-trivial
1653 ; scheduling hooks, maybe saving some information for its own sake.
1654 ; On IA64, for example, this is used for correct bundling.
1655 fselective-scheduling
1656 Common Report Var(flag_selective_scheduling) Optimization
1657 Schedule instructions using selective scheduling algorithm
1659 fselective-scheduling2
1660 Common Report Var(flag_selective_scheduling2) Optimization
1661 Run selective scheduling after reload
1663 fsel-sched-pipelining
1664 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1665 Perform software pipelining of inner loops during selective scheduling
1667 fsel-sched-pipelining-outer-loops
1668 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1669 Perform software pipelining of outer loops during selective scheduling
1671 fsel-sched-reschedule-pipelined
1672 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1673 Reschedule pipelined regions without pipelining
1675 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1676 ; of stalled insns into the ready list.
1677 fsched-stalled-insns
1678 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1679 Allow premature scheduling of queued insns
1681 fsched-stalled-insns=
1682 Common RejectNegative Joined UInteger
1683 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1685 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1686 ; be examined for a dependency on a stalled insn that is candidate for
1687 ; premature removal from the queue of stalled insns into the ready list (has
1688 ; an effect only if the flag 'sched_stalled_insns' is set).
1689 fsched-stalled-insns-dep
1690 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1691 Set dependence distance checking in premature scheduling of queued insns
1693 fsched-stalled-insns-dep=
1694 Common RejectNegative Joined UInteger
1695 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1697 fsched-group-heuristic
1698 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1699 Enable the group heuristic in the scheduler
1701 fsched-critical-path-heuristic
1702 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1703 Enable the critical path heuristic in the scheduler
1705 fsched-spec-insn-heuristic
1706 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1707 Enable the speculative instruction heuristic in the scheduler
1709 fsched-rank-heuristic
1710 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1711 Enable the rank heuristic in the scheduler
1713 fsched-last-insn-heuristic
1714 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1715 Enable the last instruction heuristic in the scheduler
1717 fsched-dep-count-heuristic
1718 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1719 Enable the dependent count heuristic in the scheduler
1722 Common Report Var(flag_section_anchors) Optimization
1723 Access data in the same section from shared anchor points
1727 Does nothing. Preserved for backward compatibility.
1730 Common Report Var(flag_zee) Init(0)
1731 Eliminate redundant zero extensions on targets that support implicit extensions.
1734 Common Report Var(flag_show_column) Init(1)
1735 Show column numbers in diagnostics, when available. Default on
1738 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1739 Disable optimizations observable by IEEE signaling NaNs
1742 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1743 Disable floating point optimizations that ignore the IEEE signedness of zero
1745 fsingle-precision-constant
1746 Common Report Var(flag_single_precision_constant) Optimization
1747 Convert floating point constants to single precision constants
1749 fsplit-ivs-in-unroller
1750 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1751 Split lifetimes of induction variables when loops are unrolled
1754 Common Report Var(flag_split_stack) Init(-1)
1755 Generate discontiguous stack frames
1758 Common Report Var(flag_split_wide_types) Optimization
1759 Split wide types into independent registers
1761 fvariable-expansion-in-unroller
1762 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1763 Apply variable expansion when loops are unrolled
1766 Common Report RejectNegative Joined
1767 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1770 Common Alias(fstack-check=, specific, no)
1771 Insert stack checking code into the program. Same as -fstack-check=specific
1774 Common Var(common_deferred_options) Defer
1776 fstack-limit-register=
1777 Common RejectNegative Joined Var(common_deferred_options) Defer
1778 -fstack-limit-register=<register> Trap if the stack goes past <register>
1780 fstack-limit-symbol=
1781 Common RejectNegative Joined Var(common_deferred_options) Defer
1782 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1785 Common Report Var(flag_stack_protect, 1)
1786 Use propolice as a stack protection method
1788 fstack-protector-all
1789 Common Report RejectNegative Var(flag_stack_protect, 2)
1790 Use a stack protection method for every function
1793 Common RejectNegative Var(flag_stack_usage)
1794 Output stack usage information on a per-function basis
1798 Does nothing. Preserved for backward compatibility.
1800 ; Nonzero if we should do (language-dependent) alias analysis.
1801 ; Typically, this analysis will assume that expressions of certain
1802 ; types do not alias expressions of certain other types. Only used
1803 ; if alias analysis (in general) is enabled.
1805 Common Report Var(flag_strict_aliasing) Optimization
1806 Assume strict aliasing rules apply
1809 Common Report Var(flag_strict_overflow)
1810 Treat signed overflow as undefined
1813 Common Report Var(flag_syntax_only)
1814 Check for syntax errors, then stop
1817 Common Report Var(flag_test_coverage)
1818 Create data files needed by \"gcov\"
1821 Common Report Var(flag_thread_jumps) Optimization
1822 Perform jump threading optimizations
1825 Common Report Var(time_report)
1826 Report the time taken by each compiler pass
1829 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1830 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1833 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1836 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1839 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1842 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1845 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1848 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1849 Reorder top level functions, variables, and asms
1852 Common Report Var(flag_tracer)
1853 Perform superblock formation via tail duplication
1855 ; Zero means that floating-point math operations cannot generate a
1856 ; (user-visible) trap. This is the case, for example, in nonstop
1857 ; IEEE 754 arithmetic.
1859 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1860 Assume floating-point operations can trap
1863 Common Report Var(flag_trapv) Optimization
1864 Trap for signed overflow in addition, subtraction and multiplication
1867 Common Report Var(flag_tree_ccp) Optimization
1868 Enable SSA-CCP optimization on trees
1871 Common Report Var(flag_tree_bit_ccp) Optimization
1872 Enable SSA-BIT-CCP optimization on trees
1876 Does nothing. Preserved for backward compatibility.
1879 Common Report Var(flag_tree_ch) Optimization
1880 Enable loop header copying on trees
1883 Common Report Var(flag_tree_copyrename) Optimization
1884 Replace SSA temporaries with better names in copies
1887 Common Report Var(flag_tree_copy_prop) Optimization
1888 Enable copy propagation on trees
1890 ftree-store-copy-prop
1892 Does nothing. Preserved for backward compatibility.
1895 Common Report Var(flag_tree_cselim) Init(2) Optimization
1896 Transform condition stores into unconditional ones
1898 ftree-switch-conversion
1899 Common Report Var(flag_tree_switch_conversion) Optimization
1900 Perform conversions of switch initializations.
1903 Common Report Var(flag_tree_dce) Optimization
1904 Enable SSA dead code elimination optimization on trees
1906 ftree-dominator-opts
1907 Common Report Var(flag_tree_dom) Optimization
1908 Enable dominator optimizations
1911 Common Report Var(flag_tree_dse) Optimization
1912 Enable dead store elimination
1915 Common Report Var(flag_tree_forwprop) Init(1) Optimization
1916 Enable forward propagation on trees
1919 Common Report Var(flag_tree_fre) Optimization
1920 Enable Full Redundancy Elimination (FRE) on trees
1922 ftree-loop-distribution
1923 Common Report Var(flag_tree_loop_distribution) Optimization
1924 Enable loop distribution on trees
1926 ftree-loop-distribute-patterns
1927 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
1928 Enable loop distribution for patterns transformed into a library call
1931 Common Report Var(flag_tree_loop_im) Init(1) Optimization
1932 Enable loop invariant motion on trees
1935 Common Alias(floop-interchange)
1936 Enable loop interchange transforms. Same as -floop-interchange
1939 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
1940 Create canonical induction variables in loops
1943 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
1944 Enable loop optimizations on tree level
1946 ftree-parallelize-loops=
1947 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
1948 Enable automatic parallelization of loops
1951 Common Report Var(flag_tree_phiprop) Init(1) Optimization
1952 Enable hoisting loads from conditional pointers.
1955 Common Report Var(flag_tree_pre) Optimization
1956 Enable SSA-PRE optimization on trees
1959 Common Report Var(flag_tree_pta) Init(1) Optimization
1960 Perform function-local points-to analysis on trees.
1963 Common Report Var(flag_tree_reassoc) Init(1) Optimization
1964 Enable reassociation on tree level
1968 Does nothing. Preserved for backward compatibility.
1971 Common Report Var(flag_tree_sink) Optimization
1972 Enable SSA code sinking on trees
1975 Common Report Var(flag_tree_sra) Optimization
1976 Perform scalar replacement of aggregates
1979 Common Report Var(flag_tree_ter) Optimization
1980 Replace temporary expressions in the SSA->normal pass
1983 Common Report Var(flag_tree_live_range_split) Optimization
1984 Perform live range splitting during the SSA->normal pass
1987 Common Report Var(flag_tree_vrp) Init(0) Optimization
1988 Perform Value Range Propagation on trees
1991 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
1992 Compile whole compilation unit at a time
1995 Common Report Var(flag_unroll_loops) Optimization
1996 Perform loop unrolling when iteration count is known
1999 Common Report Var(flag_unroll_all_loops) Optimization
2000 Perform loop unrolling for all loops
2002 ; Nonzero means that loop optimizer may assume that the induction variables
2003 ; that control loops do not overflow and that the loops with nontrivial
2004 ; exit condition are not infinite
2005 funsafe-loop-optimizations
2006 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2007 Allow loop optimizations to assume that the loops behave in normal way
2010 Common Report Var(flag_associative_math) SetByCombined
2011 Allow optimization for floating-point arithmetic which may change the
2012 result of the operation due to rounding.
2015 Common Report Var(flag_reciprocal_math) SetByCombined
2016 Same as -fassociative-math for expressions which include division.
2018 ; Nonzero means that unsafe floating-point math optimizations are allowed
2019 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2020 ; are allowed to assume that their arguments and results are "normal"
2021 ; (e.g., nonnegative for SQRT).
2022 funsafe-math-optimizations
2023 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2024 Allow math optimizations that may violate IEEE or ISO standards
2027 Common Report Var(flag_unswitch_loops) Optimization
2028 Perform loop unswitching
2031 Common Report Var(flag_unwind_tables) Optimization
2032 Just generate unwind tables for exception handling
2037 ; Positive if we should track variables, negative if we should run
2038 ; the var-tracking pass only to discard debug annotations, zero if
2039 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2040 ; will be set according to optimize, debug_info_level and debug_hooks
2041 ; in process_options ().
2043 Common Report Var(flag_var_tracking) Init(2) Optimization
2044 Perform variable tracking
2046 ; Positive if we should track variables at assignments, negative if
2047 ; we should run the var-tracking pass only to discard debug
2048 ; annotations. When flag_var_tracking_assignments ==
2049 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2050 fvar-tracking-assignments
2051 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2052 Perform variable tracking by annotating assignments
2054 ; Nonzero if we should toggle flag_var_tracking_assignments after
2055 ; processing options and computing its default. */
2056 fvar-tracking-assignments-toggle
2057 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2058 Toggle -fvar-tracking-assignments
2060 fvar-tracking-uninit
2061 Common Report Var(flag_var_tracking_uninit) Optimization
2062 Perform variable tracking and also tag variables that are uninitialized
2065 Common Report Var(flag_tree_vectorize) Optimization
2066 Enable loop vectorization on trees
2069 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2070 Enable basic block vectorization (SLP) on trees
2073 Common Report Var(flag_vect_cost_model) Optimization
2074 Enable use of cost model in vectorization
2076 ftree-vect-loop-version
2077 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2078 Enable loop versioning when doing loop vectorization on trees
2080 ftree-vectorizer-verbose=
2081 Common RejectNegative Joined UInteger
2082 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
2085 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2086 Enable copy propagation of scalar-evolution information.
2088 ; -fverbose-asm causes extra commentary information to be produced in
2089 ; the generated assembly code (to make it more readable). This option
2090 ; is generally only of use to those who actually need to read the
2091 ; generated assembly code (perhaps while debugging the compiler itself).
2092 ; -fno-verbose-asm, the default, causes the extra information
2093 ; to not be added and is useful when comparing two assembler files.
2095 Common Report Var(flag_verbose_asm)
2096 Add extra commentary to assembler output
2099 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2100 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2103 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2106 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2109 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2112 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2115 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2118 Common Report Var(flag_value_profile_transformations) Optimization
2119 Use expression value profiles in optimizations
2122 Common Report Var(flag_web) Init(2) Optimization
2123 Construct webs and split unrelated uses of single variable
2125 ftree-builtin-call-dce
2126 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2127 Enable conditional dead code elimination for builtin calls
2130 Common Report Var(flag_whole_program) Init(0) Optimization
2131 Perform whole program optimizations
2134 Common Report Var(flag_wrapv) Optimization
2135 Assume signed arithmetic overflow wraps around
2137 fzero-initialized-in-bss
2138 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2139 Put zero initialized data in the bss section
2142 Common JoinedOrMissing
2143 Generate debug information in default format
2146 Common JoinedOrMissing Negative(gdwarf-)
2147 Generate debug information in COFF format
2150 Common Joined UInteger Var(dwarf_version) Init(2) Negative(gstabs)
2151 Generate debug information in DWARF v2 (or later) format
2154 Common JoinedOrMissing
2155 Generate debug information in default extended format
2158 Common JoinedOrMissing Negative(gstabs+)
2159 Generate debug information in STABS format
2162 Common JoinedOrMissing Negative(gvms)
2163 Generate debug information in extended STABS format
2166 Common RejectNegative Var(dwarf_strict,0) Init(-1)
2167 Emit DWARF additions beyond selected version
2170 Common Report RejectNegative Var(dwarf_strict,1)
2171 Don't emit DWARF additions beyond selected version
2174 Common Report Var(flag_gtoggle)
2175 Toggle debug information generation
2178 Common JoinedOrMissing Negative(gxcoff)
2179 Generate debug information in VMS format
2182 Common JoinedOrMissing Negative(gxcoff+)
2183 Generate debug information in XCOFF format
2186 Common JoinedOrMissing Negative(gcoff)
2187 Generate debug information in extended XCOFF format
2190 Driver Joined Separate
2193 Common Joined Var(plugindir_string) Init(0)
2194 -iplugindir=<dir> Set <dir> to be the default plugin directory
2197 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2198 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory
2201 Driver Joined Separate
2206 no-canonical-prefixes
2219 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2220 -o <file> Place output into <file>
2223 Common Var(profile_flag)
2224 Enable function profiling
2227 Driver Var(pass_exit_codes)
2230 Common Var(pedantic)
2231 Issue warnings needed for strict compliance to the standard
2234 Common Var(flag_pedantic_errors)
2235 Like -pedantic but issue them as errors
2241 Driver Var(use_pipes)
2244 Driver JoinedOrMissing Var(print_file_name)
2246 print-libgcc-file-name
2249 print-multi-directory
2250 Driver Var(print_multi_directory)
2253 Driver Var(print_multi_lib)
2255 print-multi-os-directory
2256 Driver Var(print_multi_os_directory)
2259 Driver Var(print_multiarch)
2262 Driver JoinedOrMissing Var(print_prog_name)
2265 Driver Var(print_search_dirs)
2268 Driver Var(print_sysroot)
2270 print-sysroot-headers-suffix
2271 Driver Var(print_sysroot_headers_suffix)
2274 Common Var(quiet_flag) RejectDriver
2275 Do not display functions compiled or elapsed time
2293 Driver Var(report_times)
2296 Driver JoinedOrMissing
2299 Driver Joined Separate
2303 ; C option, but driver must not handle as "-u ndef".
2306 Common Driver Var(verbose_flag)
2307 Enable verbose output
2310 Common Var(version_flag) RejectDriver
2311 Display the compiler's version
2314 Common Var(inhibit_warnings)
2318 Driver Separate Var(wrapper_string)
2321 Driver Joined Separate
2324 Common RejectNegative Negative(pie)
2325 Create a shared library
2331 Driver Separate Alias(specs=)
2344 ; Documented for Fortran, but always accepted by driver.
2351 ; Documented for Go, but always accepted by driver.
2357 Common RejectNegative Negative(shared)
2358 Create a position independent executable
2361 Driver Joined Separate
2363 ; This comment is to ensure we retain the blank line above.