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)
281 Driver Alias(canonical-prefixes)
283 -no-standard-libraries
284 Driver Alias(nostdlib)
293 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
296 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
299 Driver Alias(pass-exit-codes)
302 Common Alias(pedantic)
305 Common Alias(pedantic-errors)
314 Driver Separate Alias(B)
317 Driver JoinedOrMissing Alias(B)
323 Driver Separate Alias(print-file-name=)
326 Driver JoinedOrMissing Alias(print-file-name=)
328 -print-libgcc-file-name
329 Driver Alias(print-libgcc-file-name)
331 -print-multi-directory
332 Driver Alias(print-multi-directory)
335 Driver Alias(print-multi-lib)
337 -print-multi-os-directory
338 Driver Alias(print-multi-os-directory)
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
469 Common RejectNegative Warning Alias(Wextra)
470 This switch is deprecated; use -Wextra instead
473 Driver JoinedOrMissing
476 Driver JoinedOrMissing
479 Driver JoinedOrMissing
482 Common Var(warn_aggregate_return) Warning
483 Warn about returning structures, unions or arrays
486 Common Var(warn_array_bounds) Warning
487 Warn if an array is accessed out of bounds
490 Common Var(warn_attributes) Init(1) Warning
491 Warn about inappropriate attribute usage
494 Common Var(warn_cast_align) Warning
495 Warn about pointer casts which increase alignment
498 Common Var(warn_cpp) Init(1) Warning
499 Warn when a #warning directive is encountered
501 Wdeprecated-declarations
502 Common Var(warn_deprecated_decl) Init(1) Warning
503 Warn about uses of __attribute__((deprecated)) declarations
505 Wdisabled-optimization
506 Common Var(warn_disabled_optimization) Warning
507 Warn when an optimization pass is disabled
510 Common Var(warnings_are_errors)
511 Treat all warnings as errors
515 Treat specified warning as error
518 Common Var(extra_warnings) Warning
519 Print extra (possibly unwanted) warnings
522 Common Var(flag_fatal_errors)
523 Exit on the first error occurred
526 Common RejectNegative Joined UInteger
527 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
530 Common Var(warn_inline) Warning
531 Warn when an inlined function cannot be inlined
534 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
537 Common RejectNegative Joined UInteger Warning
538 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
540 Wunsafe-loop-optimizations
541 Common Var(warn_unsafe_loop_optimizations) Warning
542 Warn if the loop cannot be optimized due to nontrivial assumptions.
545 Common Var(warn_missing_noreturn) Warning
546 Warn about functions which might be candidates for __attribute__((noreturn))
549 Common Var(warn_mudflap) Init(1) Warning
550 Warn about constructs not instrumented by -fmudflap
553 Common Var(warn_overflow) Init(1) Warning
554 Warn about overflow in arithmetic expressions
557 Common Var(warn_packed) Warning
558 Warn when the packed attribute has no effect on struct layout
561 Common Var(warn_padded) Warning
562 Warn when padding is required to align structure members
565 Common Var(warn_shadow) Warning
566 Warn when one local variable shadows another
569 Common Var(warn_stack_protect) Warning
570 Warn when not issuing stack smashing protection for some reason
574 Warn about code which might break strict aliasing rules
577 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
578 Warn about code which might break strict aliasing rules
582 Warn about optimizations that assume that signed overflow is undefined
585 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
586 Warn about optimizations that assume that signed overflow is undefined
588 Wsuggest-attribute=const
589 Common Var(warn_suggest_attribute_const) Warning
590 Warn about functions which might be candidates for __attribute__((const))
592 Wsuggest-attribute=pure
593 Common Var(warn_suggest_attribute_pure) Warning
594 Warn about functions which might be candidates for __attribute__((pure))
596 Wsuggest-attribute=noreturn
597 Common Var(warn_suggest_attribute_noreturn) Warning
598 Warn about functions which might be candidates for __attribute__((noreturn))
601 Common Var(warn_switch) Warning
602 Warn about enumerated switches, with no default, missing a case
605 Common Var(warn_switch_default) Warning
606 Warn about enumerated switches missing a \"default:\" statement
609 Common Var(warn_switch_enum) Warning
610 Warn about all enumerated switches missing a specific case
613 Common Var(warn_system_headers) Warning
614 Do not suppress warnings from system headers
617 Common Var(warn_trampolines) Warning
618 Warn whenever a trampoline is generated
620 ; FIXME. The following -Wthread-* flags are placeholders to prevent
621 ; confusing the compiler when applications are built with these flags.
622 ; Actual support for these flags is being implemented in the
623 ; thread-annotations branch.
625 Common Var(warn_thread_safety) Warning
626 Warn about potential thread safety issues when the code is annotated with thread safety attributes
628 Wthread-unguarded-var
629 Common Var(warn_thread_unguarded_var) Init(1) Warning
630 Warn about shared variables not properly protected by locks specified in the attributes
632 Wthread-unguarded-func
633 Common Var(warn_thread_unguarded_func) Init(1) Warning
634 Warn about function calls not properly protected by locks specified in the attributes
636 Wthread-mismatched-lock-order
637 Common Var(warn_thread_mismatched_lock_order) Init(1) Warning
638 Warn about lock acquisition order inconsistent with what specified in the attributes
640 Wthread-mismatched-lock-acq-rel
641 Common Var(warn_thread_mismatched_lock_acq_rel) Init(1) Warning
642 Warn about mismatched lock acquisition and release
644 Wthread-reentrant-lock
645 Common Var(warn_thread_reentrant_lock) Init(1) Warning
646 Warn about a lock being acquired recursively
648 Wthread-unsupported-lock-name
649 Common Var(warn_unsupported_lock_name) Init(0) Warning
650 Warn about uses of unsupported lock names in attributes
653 Common Var(warn_type_limits) Init(-1) Warning
654 Warn if a comparison is always true or always false due to the limited range of the data type
657 Common Var(warn_uninitialized) Init(-1) Warning
658 Warn about uninitialized automatic variables
662 Does nothing. Preserved for backward compatibility.
665 Common Var(warn_unused) Init(0) Warning
666 Enable all -Wunused- warnings
668 Wunused-but-set-parameter
669 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
670 Warn when a function parameter is only set, otherwise unused
672 Wunused-but-set-variable
673 Common Var(warn_unused_but_set_variable) Init(-1) Warning
674 Warn when a variable is only set, otherwise unused
677 Common Var(warn_unused_function) Init(-1) Warning
678 Warn when a function is unused
681 Common Var(warn_unused_label) Init(-1) Warning
682 Warn when a label is unused
685 Common Var(warn_unused_parameter) Init(-1) Warning
686 Warn when a function parameter is unused
689 Common Var(warn_unused_value) Init(-1) Warning
690 Warn when an expression value is unused
693 Common Var(warn_unused_variable) Init(-1) Warning
694 Warn when a variable is unused
697 Common Var(warn_coverage_mismatch) Init(1) Warning
698 Warn in case profiles in -fprofile-use do not match
713 Common Separate Var(aux_info_file_name)
714 -aux-info <file> Emit declaration information into <file>
717 Common Joined Alias(aux-info)
720 Common Separate RejectDriver Var(aux_base_name)
723 Common Separate RejectDriver
733 -d<letters> Enable dumps from specific passes of the compiler
736 Common Separate Var(dump_base_name)
737 -dumpbase <file> Set the file basename to be used for dumps
740 Common Separate Var(dump_dir_name)
741 -dumpdir <dir> Set the directory name to be used for dumps
753 Driver Joined Separate
755 ; This option has historically been passed down to the linker by an
756 ; accident of a %{e*} spec, so ensure it continues to be passed down
757 ; as a single option. The supported option for this purpose is
758 ; -rdynamic. See PR 47390.
762 ; The version of the C++ ABI in use. The following values are allowed:
764 ; 0: The version of the ABI believed most conformant with the C++ ABI
765 ; specification. This ABI may change as bugs are discovered and fixed.
766 ; Therefore, 0 will not necessarily indicate the same ABI in different
769 ; 1: The version of the ABI first used in G++ 3.2.
771 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
773 ; 3: The version of the ABI that fixes the missing underscore
774 ; in template non-type arguments of pointer type.
776 ; 4: The version of the ABI that introduces unambiguous mangling of
777 ; vector types. First selectable in G++ 4.5.
779 ; 5: The version of the ABI that ignores attribute const/noreturn
780 ; in function pointer mangling, and corrects mangling of decltype and
781 ; function parameters used in other parameters and the return type.
782 ; First selectable in G++ 4.6.
784 ; Additional positive integers will be assigned as new versions of
785 ; the ABI become the default version of the ABI.
787 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
790 Common Report Var(align_functions,0) Optimization UInteger
791 Align the start of functions
794 Common RejectNegative Joined UInteger Var(align_functions)
797 Common Report Var(align_jumps,0) Optimization UInteger
798 Align labels which are only reached by jumping
801 Common RejectNegative Joined UInteger Var(align_jumps)
804 Common Report Var(align_labels,0) Optimization UInteger
808 Common RejectNegative Joined UInteger Var(align_labels)
811 Common Report Var(align_loops,0) Optimization UInteger
812 Align the start of loops
815 Common RejectNegative Joined UInteger Var(align_loops)
819 Does nothing. Preserved for backward compatibility.
823 Does nothing. Preserved for backward compatibility.
825 fargument-noalias-global
827 Does nothing. Preserved for backward compatibility.
829 fargument-noalias-anything
831 Does nothing. Preserved for backward compatibility.
833 fasynchronous-unwind-tables
834 Common Report Var(flag_asynchronous_unwind_tables) Optimization
835 Generate unwind tables that are exact at each instruction boundary
838 Common Report Var(flag_auto_inc_dec) Init(1)
839 Generate auto-inc/dec instructions
841 ; -fcheck-bounds causes gcc to generate array bounds checks.
842 ; For C, C++ and ObjC: defaults off.
843 ; For Java: defaults to on.
844 ; For Fortran: defaults to off.
846 Common Report Var(flag_bounds_check)
847 Generate code to check bounds before indexing arrays
850 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
851 Replace add, compare, branch with branch on count register
853 fbranch-probabilities
854 Common Report Var(flag_branch_probabilities) Optimization
855 Use profiling information for branch probabilities
857 fbranch-target-load-optimize
858 Common Report Var(flag_branch_target_load_optimize) Optimization
859 Perform branch target load optimization before prologue / epilogue threading
861 fbranch-target-load-optimize2
862 Common Report Var(flag_branch_target_load_optimize2) Optimization
863 Perform branch target load optimization after prologue / epilogue threading
866 Common Report Var(flag_btr_bb_exclusive) Optimization
867 Restrict target load migration not to re-use registers in any basic block
870 Common Joined RejectNegative Var(common_deferred_options) Defer
871 -fcall-saved-<register> Mark <register> as being preserved across functions
874 Common Joined RejectNegative Var(common_deferred_options) Defer
875 -fcall-used-<register> Mark <register> as being corrupted by function calls
877 ; Nonzero for -fcaller-saves: allocate values in regs that need to
878 ; be saved across function calls, if that produces overall better code.
879 ; Optional now, so people can test it.
881 Common Report Var(flag_caller_saves) Optimization
882 Save registers around function calls
885 Common Report Var(flag_check_data_deps)
886 Compare the results of several data dependence analyzers.
888 fcombine-stack-adjustments
889 Common Report Var(flag_combine_stack_adjustments) Optimization
890 Looks for opportunities to reduce stack adjustments and stack references.
893 Common Report Var(flag_no_common,0) Optimization
894 Do not put uninitialized globals in the common section
898 ; Converted by the driver to -fcompare-debug= options.
901 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
902 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
904 fcompare-debug-second
905 Common Driver RejectNegative Var(flag_compare_debug)
906 Run only the second compilation of -fcompare-debug
909 Common Report Var(flag_compare_elim_after_reload) Optimization
910 Perform comparison elimination after register allocation has finished
913 Common Var(flag_conserve_stack) Optimization
914 Do not perform optimizations increasing noticeably stack usage
917 Common Report Var(flag_cprop_registers) Optimization
918 Perform a register copy-propagation optimization pass
921 Common Report Var(flag_crossjumping) Optimization
922 Perform cross-jumping optimization
925 Common Report Var(flag_cse_follow_jumps) Optimization
926 When running CSE, follow jumps to their targets
930 Does nothing. Preserved for backward compatibility.
933 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
934 Omit range reduction step when performing complex division
937 Common Report Var(flag_cx_fortran_rules) Optimization
938 Complex multiplication and division follow Fortran rules
941 Common Report Var(flag_data_sections) Optimization
942 Place data items into their own section
945 Common Report Var(common_deferred_options) Defer
946 List all available debugging counters with their limits and counts.
949 Common RejectNegative Joined Var(common_deferred_options) Defer
950 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
953 Common Joined RejectNegative Var(common_deferred_options) Defer
954 Map one directory name to another in debug information
956 ; Nonzero for -fdefer-pop: don't pop args after each function call
957 ; instead save them up to pop many calls' args with one insns.
959 Common Report Var(flag_defer_pop) Optimization
960 Defer popping functions args from stack until later
963 Common Report Var(flag_delayed_branch) Optimization
964 Attempt to fill delay slots of branch instructions
966 fdelete-null-pointer-checks
967 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
968 Delete useless null pointer checks
971 Common Report Var(flag_devirtualize) Optimization
972 Try to convert virtual calls to direct ones.
974 fdiagnostics-show-location=
975 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
976 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
978 ; Required for these enum values.
983 Name(diagnostic_prefixing_rule) Type(int)
986 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
989 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
991 fdiagnostics-show-option
992 Common Var(flag_diagnostics_show_option) Init(1)
993 Amend appropriate diagnostic messages with the command line option that controls them
996 Common Joined RejectNegative Var(common_deferred_options) Defer
997 -fdump-<type> Dump various compiler internals to a file
1000 Driver RejectNegative
1003 Common RejectNegative Joined Var(flag_dump_final_insns)
1004 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1007 Common RejectNegative Joined Var(flag_dump_go_spec)
1008 -fdump-go-spec=filename Write all declarations to file as Go code
1011 Common Report Var(flag_dump_noaddr)
1012 Suppress output of addresses in debugging dumps
1015 Common Report Var(flag_dump_unnumbered)
1016 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1018 fdump-unnumbered-links
1019 Common Report Var(flag_dump_unnumbered_links)
1020 Suppress output of previous and next insn numbers in debugging dumps
1023 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1024 Enable CFI tables via GAS assembler directives.
1027 Common Report Var(flag_early_inlining) Init(1) Optimization
1028 Perform early inlining
1030 feliminate-dwarf2-dups
1031 Common Report Var(flag_eliminate_dwarf2_dups)
1032 Perform DWARF2 duplicate elimination
1035 Common Report Var(flag_ipa_sra) Init(0) Optimization
1036 Perform interprocedural reduction of aggregates
1038 feliminate-unused-debug-symbols
1039 Common Report Var(flag_debug_only_used_symbols)
1040 Perform unused type elimination in debug info
1042 feliminate-unused-debug-types
1043 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1044 Perform unused type elimination in debug info
1046 femit-class-debug-always
1047 Common Report Var(flag_emit_class_debug_always) Init(0)
1048 Do not suppress C++ class debug information.
1051 Common Report Var(flag_exceptions) Optimization
1052 Enable exception handling
1054 fexpensive-optimizations
1055 Common Report Var(flag_expensive_optimizations) Optimization
1056 Perform a number of minor, expensive optimizations
1059 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1060 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1063 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1066 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1069 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1075 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1076 Assume no NaNs or infinities are generated
1079 Common Joined RejectNegative Var(common_deferred_options) Defer
1080 -ffixed-<register> Mark <register> as being unavailable to the compiler
1083 Common Report Var(flag_float_store) Optimization
1084 Don't allocate floats and doubles in extended-precision registers
1088 Does nothing. Preserved for backward compatibility.
1091 Common Report Var(flag_forward_propagate) Optimization
1092 Perform a forward propagation pass on RTL
1095 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1096 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1099 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1102 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1104 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1106 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1109 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1111 ; Nonzero means don't put addresses of constant functions in registers.
1112 ; Used for compiling the Unix kernel, where strange substitutions are
1113 ; done on the assembly output.
1115 Common Report Var(flag_no_function_cse,0)
1116 Allow function addresses to be held in registers
1119 Common Report Var(flag_function_sections)
1120 Place each function into its own section
1123 Common Report Var(flag_gcse) Optimization
1124 Perform global common subexpression elimination
1127 Common Report Var(flag_gcse_lm) Init(1) Optimization
1128 Perform enhanced load motion during global common subexpression elimination
1131 Common Report Var(flag_gcse_sm) Init(0) Optimization
1132 Perform store motion after global common subexpression elimination
1135 Common Report Var(flag_gcse_las) Init(0) Optimization
1136 Perform redundant load after store elimination in global common subexpression
1140 Common Report Var(flag_gcse_after_reload) Optimization
1141 Perform global common subexpression elimination after register allocation
1144 ; This option is not documented yet as its semantics will change.
1146 Common Report Var(flag_graphite)
1147 Enable in and out of Graphite representation
1150 Common Report Var(flag_graphite_identity) Optimization
1151 Enable Graphite Identity transformation
1153 floop-parallelize-all
1154 Common Report Var(flag_loop_parallelize_all) Optimization
1155 Mark all loops as parallel
1158 Common Report Var(flag_loop_strip_mine) Optimization
1159 Enable Loop Strip Mining transformation
1162 Common Report Var(flag_loop_interchange) Optimization
1163 Enable Loop Interchange transformation
1166 Common Report Var(flag_loop_block) Optimization
1167 Enable Loop Blocking transformation
1170 Common Report Var(flag_loop_flatten) Optimization
1171 Enable Loop Flattening transformation
1173 fstrict-volatile-bitfields
1174 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1175 Force bitfield accesses to match their type width
1177 fguess-branch-probability
1178 Common Report Var(flag_guess_branch_prob) Optimization
1179 Enable guessing of branch probabilities
1181 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1182 ; Generate position-independent code for executables if possible
1183 ; On SVR4 targets, it also controls whether or not to emit a
1184 ; string identifying the compiler.
1186 Common Report Var(flag_no_ident,0)
1187 Process #ident directives
1190 Common Report Var(flag_if_conversion) Optimization
1191 Perform conversion of conditional jumps to branchless equivalents
1194 Common Report Var(flag_if_conversion2) Optimization
1195 Perform conversion of conditional jumps to conditional execution
1197 ftree-loop-if-convert
1198 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1199 Convert conditional jumps in innermost loops to branchless equivalents
1201 ftree-loop-if-convert-stores
1202 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1203 Also if-convert conditional jumps containing memory writes
1205 ; -finhibit-size-directive inhibits output of .size for ELF.
1206 ; This is used only for compiling crtstuff.c,
1207 ; and it may be extended to other effects
1208 ; needed for crtstuff.c on other systems.
1209 finhibit-size-directive
1210 Common Report Var(flag_inhibit_size_directive)
1211 Do not generate .size directives
1214 Common Report Var(flag_indirect_inlining)
1215 Perform indirect inlining
1217 ; Nonzero means that functions declared `inline' will be treated
1218 ; as `static'. Prevents generation of zillions of copies of unused
1219 ; static inline functions; instead, `inlines' are written out
1220 ; only when actually used. Used in conjunction with -g. Also
1221 ; does the right thing with #pragma interface.
1223 Common Report Var(flag_no_inline,0) Init(0)
1224 Pay attention to the \"inline\" keyword
1226 finline-small-functions
1227 Common Report Var(flag_inline_small_functions) Optimization
1228 Integrate simple functions into their callers when code size is known to not growth
1231 Common Report Var(flag_inline_functions) Optimization
1232 Integrate simple functions into their callers
1234 finline-functions-called-once
1235 Common Report Var(flag_inline_functions_called_once) Init(1) Optimization
1236 Integrate functions called once into their callers
1239 Common RejectNegative Joined Alias(finline-limit=)
1242 Common RejectNegative Joined UInteger
1243 -finline-limit=<number> Limit the size of inlined functions to <number>
1245 finstrument-functions
1246 Common Report Var(flag_instrument_function_entry_exit)
1247 Instrument function entry and exit with profiling calls
1249 finstrument-functions-exclude-function-list=
1250 Common RejectNegative Joined
1251 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1253 finstrument-functions-exclude-file-list=
1254 Common RejectNegative Joined
1255 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1258 Common Report Var(flag_ipa_cp) Optimization
1259 Perform Interprocedural constant propagation
1262 Common Report Var(flag_ipa_cp_clone) Optimization
1263 Perform cloning to make Interprocedural constant propagation stronger
1266 Common Report Var(flag_ipa_profile) Init(0) Optimization
1267 Perform interprocedural profile propagation
1270 Common Report Var(flag_ipa_pta) Init(0) Optimization
1271 Perform interprocedural points-to analysis
1274 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1275 Discover pure and const functions
1278 Common Report Var(flag_ipa_reference) Init(0) Optimization
1279 Discover readonly and non addressable static variables
1282 Common Report Var(flag_ipa_matrix_reorg) Optimization
1283 Perform matrix layout flattening and transposing based
1284 on profiling information.
1288 Does nothing. Preserved for backward compatibility.
1291 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1292 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1295 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1298 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1301 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1304 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_MIXED)
1305 -fira-region=[one|all|mixed] Set regions for IRA
1308 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1311 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1314 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1317 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1320 Common Report Var(flag_ira_loop_pressure)
1321 Use IRA based register pressure calculation
1322 in RTL loop optimizations.
1324 fira-share-save-slots
1325 Common Report Var(flag_ira_share_save_slots) Init(1)
1326 Share slots for saving different hard registers.
1328 fira-share-spill-slots
1329 Common Report Var(flag_ira_share_spill_slots) Init(1)
1330 Share stack slots for spilled pseudo-registers.
1333 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1334 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1337 Common Report Var(flag_ivopts) Init(1) Optimization
1338 Optimize induction variables on trees
1341 Common Var(flag_jump_tables) Init(1) Optimization
1342 Use jump tables for sufficiently large switch statements
1344 fkeep-inline-functions
1345 Common Report Var(flag_keep_inline_functions)
1346 Generate code for functions even if they are fully inlined
1349 Common Report Var(flag_keep_static_consts) Init(1)
1350 Emit static const variables even if they are not used
1353 Common Report Var(flag_leading_underscore) Init(-1)
1354 Give external symbols a leading underscore
1358 Does nothing. Preserved for backward compatibility.
1362 Enable link-time optimization.
1365 Common RejectNegative Joined Var(flag_lto)
1366 Link-time optimization with number of parallel jobs or jobserver.
1369 Common Var(flag_lto_partition_1to1)
1370 Partition functions and vars at linktime based on object files they originate from
1372 flto-partition=balanced
1373 Common Var(flag_lto_partition_balanced)
1374 Partition functions and vars at linktime into approximately same sized buckets
1377 Common Var(flag_lto_partition_none)
1378 Disable partioning and streaming
1380 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1381 flto-compression-level=
1382 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1383 -flto-compression-level=<number> Use zlib compression level <number> for IL
1386 Common Report Var(flag_lto_report) Init(0) Optimization
1387 Report various link-time optimization statistics
1390 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1391 Set errno after built-in math functions
1394 Common Joined RejectNegative UInteger Var(flag_max_errors)
1395 -fmax-errors=<number> Maximum number of errors to report
1398 Common Report Var(mem_report)
1399 Report on permanent memory allocation
1401 ; This will attempt to merge constant section constants, if 1 only
1402 ; string constants and constants from constant pool, if 2 also constant
1404 fmerge-all-constants
1405 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1406 Attempt to merge identical constants and constant variables
1409 Common Report Var(flag_merge_constants,1) Optimization
1410 Attempt to merge identical constants across compilation units
1412 fmerge-debug-strings
1413 Common Report Var(flag_merge_debug_strings) Init(1)
1414 Attempt to merge identical debug strings across compilation units
1417 Common RejectNegative Joined UInteger
1418 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1421 Common Report Var(flag_modulo_sched) Optimization
1422 Perform SMS based modulo scheduling before the first scheduling pass
1424 fmodulo-sched-allow-regmoves
1425 Common Report Var(flag_modulo_sched_allow_regmoves)
1426 Perform SMS based modulo scheduling with register moves allowed
1428 fmove-loop-invariants
1429 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1430 Move loop invariant computations out of loops
1433 Common RejectNegative Report Var(flag_mudflap)
1434 Add mudflap bounds-checking instrumentation for single-threaded program
1437 Common RejectNegative Report Var(flag_mudflap,2)
1438 Add mudflap bounds-checking instrumentation for multi-threaded program
1441 Common RejectNegative Report Var(flag_mudflap_ignore_reads)
1442 Ignore read operations when inserting mudflap instrumentation
1445 Common Var(flag_dce) Init(1) Optimization
1446 Use the RTL dead code elimination pass
1449 Common Var(flag_dse) Init(1) Optimization
1450 Use the RTL dead store elimination pass
1452 freschedule-modulo-scheduled-loops
1453 Common Report Var(flag_resched_modulo_sched) Optimization
1454 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1456 fnon-call-exceptions
1457 Common Report Var(flag_non_call_exceptions) Optimization
1458 Support synchronous non-call exceptions
1461 Common Report Var(flag_omit_frame_pointer) Optimization
1462 When possible do not generate stack frames
1464 foptimize-register-move
1465 Common Report Var(flag_regmove) Optimization
1466 Do the full register move optimization pass
1468 foptimize-sibling-calls
1469 Common Report Var(flag_optimize_sibling_calls) Optimization
1470 Optimize sibling and tail recursive calls
1473 Common Report Var(flag_partial_inlining)
1474 Perform partial inlining
1477 Common Report Var(pre_ipa_mem_report)
1478 Report on memory allocation before interprocedural optimization
1480 fpost-ipa-mem-report
1481 Common Report Var(post_ipa_mem_report)
1482 Report on memory allocation before interprocedural optimization
1485 Common Report Var(flag_pack_struct) Optimization
1486 Pack structure members together without holes
1489 Common RejectNegative Joined UInteger Optimization
1490 -fpack-struct=<number> Set initial maximum structure member alignment
1493 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1494 Return small aggregates in memory, not registers
1497 Common Report Var(flag_peel_loops) Optimization
1498 Perform loop peeling
1501 Common Report Var(flag_no_peephole,0) Optimization
1502 Enable machine specific peephole optimizations
1505 Common Report Var(flag_peephole2) Optimization
1506 Enable an RTL peephole pass before sched2
1509 Common Report Var(flag_pic,2)
1510 Generate position-independent code if possible (large mode)
1513 Common Report Var(flag_pie,2)
1514 Generate position-independent code for executables if possible (large mode)
1517 Common Report Var(flag_pic,1)
1518 Generate position-independent code if possible (small mode)
1521 Common Report Var(flag_pie,1)
1522 Generate position-independent code for executables if possible (small mode)
1525 Common Joined RejectNegative Var(common_deferred_options) Defer
1526 Specify a plugin to load
1529 Common Joined RejectNegative Var(common_deferred_options) Defer
1530 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1532 fpredictive-commoning
1533 Common Report Var(flag_predictive_commoning) Optimization
1534 Run predictive commoning optimization.
1536 fprefetch-loop-arrays
1537 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1538 Generate prefetch instructions, if available, for arrays in loops
1541 Common Report Var(profile_flag)
1542 Enable basic program profiling code
1545 Common Report Var(profile_arc_flag)
1546 Insert arc-based program profiling code
1549 Common Joined RejectNegative Var(profile_data_prefix)
1550 Set the top-level directory for storing the profile data.
1551 The default is 'pwd'.
1554 Common Report Var(flag_profile_correction)
1555 Enable correction of flow inconsistent profile data input
1559 Enable common options for generating profile info for profile feedback directed optimizations
1562 Common Joined RejectNegative
1563 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1566 Common Var(flag_profile_use)
1567 Enable common options for performing profile feedback directed optimizations
1570 Common Joined RejectNegative
1571 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1574 Common Report Var(flag_profile_values)
1575 Insert code to profile values of expressions
1578 Common Var(common_deferred_options) Defer
1581 Common Joined RejectNegative Var(common_deferred_options) Defer
1582 -frandom-seed=<string> Make compile reproducible using <string>
1584 ; This switch causes the command line that was used to create an
1585 ; object file to be recorded into the object file. The exact format
1586 ; of this recording is target and binary file format dependent.
1587 ; It is related to the -fverbose-asm switch, but that switch only
1588 ; records information in the assembler output file as comments, so
1589 ; they never reach the object file.
1590 frecord-gcc-switches
1591 Common Report Var(flag_record_gcc_switches)
1592 Record gcc command line switches in the object file.
1595 Common Report Var(flag_pcc_struct_return,0) Optimization
1596 Return small aggregates in registers
1599 Common Report Var(flag_regmove) Optimization
1600 Enables a register move optimization
1603 Common Report Var(flag_rename_registers) Init(2) Optimization
1604 Perform a register renaming optimization pass
1607 Common Report Var(flag_reorder_blocks) Optimization
1608 Reorder basic blocks to improve code placement
1610 freorder-blocks-and-partition
1611 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1612 Reorder basic blocks and partition into hot and cold sections
1615 Common Report Var(flag_reorder_functions) Optimization
1616 Reorder functions to improve code placement
1618 frerun-cse-after-loop
1619 Common Report Var(flag_rerun_cse_after_loop) Optimization
1620 Add a common subexpression elimination pass after loop optimizations
1624 Does nothing. Preserved for backward compatibility.
1627 Common Report Var(flag_rounding_math) Optimization SetByCombined
1628 Disable optimizations that assume default FP rounding behavior
1631 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1632 Enable scheduling across basic blocks
1635 Common Report Var(flag_sched_pressure) Init(0) Optimization
1636 Enable register pressure sensitive insn scheduling
1639 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1640 Allow speculative motion of non-loads
1643 Common Report Var(flag_schedule_speculative_load) Optimization
1644 Allow speculative motion of some loads
1646 fsched-spec-load-dangerous
1647 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1648 Allow speculative motion of more loads
1651 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1652 -fsched-verbose=<number> Set the verbosity level of the scheduler
1654 fsched2-use-superblocks
1655 Common Report Var(flag_sched2_use_superblocks) Optimization
1656 If scheduling post reload, do superblock scheduling
1660 Does nothing. Preserved for backward compatibility.
1663 Common Report Var(flag_schedule_insns) Optimization
1664 Reschedule instructions before register allocation
1667 Common Report Var(flag_schedule_insns_after_reload) Optimization
1668 Reschedule instructions after register allocation
1670 ; This flag should be on when a target implements non-trivial
1671 ; scheduling hooks, maybe saving some information for its own sake.
1672 ; On IA64, for example, this is used for correct bundling.
1673 fselective-scheduling
1674 Common Report Var(flag_selective_scheduling) Optimization
1675 Schedule instructions using selective scheduling algorithm
1677 fselective-scheduling2
1678 Common Report Var(flag_selective_scheduling2) Optimization
1679 Run selective scheduling after reload
1681 fsel-sched-pipelining
1682 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1683 Perform software pipelining of inner loops during selective scheduling
1685 fsel-sched-pipelining-outer-loops
1686 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1687 Perform software pipelining of outer loops during selective scheduling
1689 fsel-sched-reschedule-pipelined
1690 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1691 Reschedule pipelined regions without pipelining
1693 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1694 ; of stalled insns into the ready list.
1695 fsched-stalled-insns
1696 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1697 Allow premature scheduling of queued insns
1699 fsched-stalled-insns=
1700 Common RejectNegative Joined UInteger
1701 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1703 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1704 ; be examined for a dependency on a stalled insn that is candidate for
1705 ; premature removal from the queue of stalled insns into the ready list (has
1706 ; an effect only if the flag 'sched_stalled_insns' is set).
1707 fsched-stalled-insns-dep
1708 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1709 Set dependence distance checking in premature scheduling of queued insns
1711 fsched-stalled-insns-dep=
1712 Common RejectNegative Joined UInteger
1713 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1715 fsched-group-heuristic
1716 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1717 Enable the group heuristic in the scheduler
1719 fsched-critical-path-heuristic
1720 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1721 Enable the critical path heuristic in the scheduler
1723 fsched-spec-insn-heuristic
1724 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1725 Enable the speculative instruction heuristic in the scheduler
1727 fsched-rank-heuristic
1728 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1729 Enable the rank heuristic in the scheduler
1731 fsched-last-insn-heuristic
1732 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1733 Enable the last instruction heuristic in the scheduler
1735 fsched-dep-count-heuristic
1736 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1737 Enable the dependent count heuristic in the scheduler
1740 Common Report Var(flag_section_anchors) Optimization
1741 Access data in the same section from shared anchor points
1745 Does nothing. Preserved for backward compatibility.
1748 Common Report Var(flag_zee) Init(0)
1749 Eliminate redundant zero extensions on targets that support implicit extensions.
1752 Common Report Var(flag_show_column) Init(1)
1753 Show column numbers in diagnostics, when available. Default on
1756 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1757 Disable optimizations observable by IEEE signaling NaNs
1760 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1761 Disable floating point optimizations that ignore the IEEE signedness of zero
1763 fsingle-precision-constant
1764 Common Report Var(flag_single_precision_constant) Optimization
1765 Convert floating point constants to single precision constants
1767 fsplit-ivs-in-unroller
1768 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1769 Split lifetimes of induction variables when loops are unrolled
1772 Common Report Var(flag_split_stack) Init(-1)
1773 Generate discontiguous stack frames
1776 Common Report Var(flag_split_wide_types) Optimization
1777 Split wide types into independent registers
1779 fvariable-expansion-in-unroller
1780 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1781 Apply variable expansion when loops are unrolled
1784 Common Report RejectNegative Joined
1785 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1788 Common Alias(fstack-check=, specific, no)
1789 Insert stack checking code into the program. Same as -fstack-check=specific
1792 Common Var(common_deferred_options) Defer
1794 fstack-limit-register=
1795 Common RejectNegative Joined Var(common_deferred_options) Defer
1796 -fstack-limit-register=<register> Trap if the stack goes past <register>
1798 fstack-limit-symbol=
1799 Common RejectNegative Joined Var(common_deferred_options) Defer
1800 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1803 Common Report Var(flag_stack_protect, 1)
1804 Use propolice as a stack protection method
1806 fstack-protector-all
1807 Common Report RejectNegative Var(flag_stack_protect, 2)
1808 Use a stack protection method for every function
1811 Common RejectNegative Var(flag_stack_usage)
1812 Output stack usage information on a per-function basis
1816 Does nothing. Preserved for backward compatibility.
1818 ; Nonzero if we should do (language-dependent) alias analysis.
1819 ; Typically, this analysis will assume that expressions of certain
1820 ; types do not alias expressions of certain other types. Only used
1821 ; if alias analysis (in general) is enabled.
1823 Common Report Var(flag_strict_aliasing) Optimization
1824 Assume strict aliasing rules apply
1827 Common Report Var(flag_strict_overflow)
1828 Treat signed overflow as undefined
1831 Common Report Var(flag_syntax_only)
1832 Check for syntax errors, then stop
1835 Common Report Var(flag_test_coverage)
1836 Create data files needed by \"gcov\"
1839 Common Report Var(flag_thread_jumps) Optimization
1840 Perform jump threading optimizations
1843 Common Report Var(time_report)
1844 Report the time taken by each compiler pass
1847 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1848 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1851 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1854 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1857 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1860 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1863 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1866 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1867 Reorder top level functions, variables, and asms
1870 Common Report Var(flag_tracer)
1871 Perform superblock formation via tail duplication
1873 ; Zero means that floating-point math operations cannot generate a
1874 ; (user-visible) trap. This is the case, for example, in nonstop
1875 ; IEEE 754 arithmetic.
1877 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1878 Assume floating-point operations can trap
1881 Common Report Var(flag_trapv) Optimization
1882 Trap for signed overflow in addition, subtraction and multiplication
1885 Common Report Var(flag_tree_ccp) Optimization
1886 Enable SSA-CCP optimization on trees
1889 Common Report Var(flag_tree_bit_ccp) Optimization
1890 Enable SSA-BIT-CCP optimization on trees
1894 Does nothing. Preserved for backward compatibility.
1897 Common Report Var(flag_tree_ch) Optimization
1898 Enable loop header copying on trees
1901 Common Report Var(flag_tree_copyrename) Optimization
1902 Replace SSA temporaries with better names in copies
1905 Common Report Var(flag_tree_copy_prop) Optimization
1906 Enable copy propagation on trees
1908 ftree-store-copy-prop
1910 Does nothing. Preserved for backward compatibility.
1913 Common Report Var(flag_tree_cselim) Init(2) Optimization
1914 Transform condition stores into unconditional ones
1916 ftree-switch-conversion
1917 Common Report Var(flag_tree_switch_conversion) Optimization
1918 Perform conversions of switch initializations.
1921 Common Report Var(flag_tree_dce) Optimization
1922 Enable SSA dead code elimination optimization on trees
1924 ftree-dominator-opts
1925 Common Report Var(flag_tree_dom) Optimization
1926 Enable dominator optimizations
1929 Common Report Var(flag_tree_dse) Optimization
1930 Enable dead store elimination
1933 Common Report Var(flag_tree_forwprop) Init(1) Optimization
1934 Enable forward propagation on trees
1937 Common Report Var(flag_tree_fre) Optimization
1938 Enable Full Redundancy Elimination (FRE) on trees
1940 ftree-loop-distribution
1941 Common Report Var(flag_tree_loop_distribution) Optimization
1942 Enable loop distribution on trees
1944 ftree-loop-distribute-patterns
1945 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
1946 Enable loop distribution for patterns transformed into a library call
1949 Common Report Var(flag_tree_loop_im) Init(1) Optimization
1950 Enable loop invariant motion on trees
1953 Common Alias(floop-interchange)
1954 Enable loop interchange transforms. Same as -floop-interchange
1957 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
1958 Create canonical induction variables in loops
1961 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
1962 Enable loop optimizations on tree level
1964 ftree-parallelize-loops=
1965 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
1966 Enable automatic parallelization of loops
1969 Common Report Var(flag_tree_phiprop) Init(1) Optimization
1970 Enable hoisting loads from conditional pointers.
1973 Common Report Var(flag_tree_pre) Optimization
1974 Enable SSA-PRE optimization on trees
1977 Common Report Var(flag_tree_pta) Init(1) Optimization
1978 Perform function-local points-to analysis on trees.
1981 Common Report Var(flag_tree_reassoc) Init(1) Optimization
1982 Enable reassociation on tree level
1986 Does nothing. Preserved for backward compatibility.
1989 Common Report Var(flag_tree_sink) Optimization
1990 Enable SSA code sinking on trees
1993 Common Report Var(flag_tree_sra) Optimization
1994 Perform scalar replacement of aggregates
1997 Common Report Var(flag_tree_ter) Optimization
1998 Replace temporary expressions in the SSA->normal pass
2001 Common Report Var(flag_tree_live_range_split) Optimization
2002 Perform live range splitting during the SSA->normal pass
2005 Common Report Var(flag_tree_vrp) Init(0) Optimization
2006 Perform Value Range Propagation on trees
2008 fstrict-enum-precision
2009 Common Report Var(flag_strict_enum_precision) Init(1) Optimization
2010 Perform transformations based on enum precision
2013 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2014 Compile whole compilation unit at a time
2017 Common Report Var(flag_unroll_loops) Optimization
2018 Perform loop unrolling when iteration count is known
2021 Common Report Var(flag_unroll_all_loops) Optimization
2022 Perform loop unrolling for all loops
2024 ; Nonzero means that loop optimizer may assume that the induction variables
2025 ; that control loops do not overflow and that the loops with nontrivial
2026 ; exit condition are not infinite
2027 funsafe-loop-optimizations
2028 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2029 Allow loop optimizations to assume that the loops behave in normal way
2032 Common Report Var(flag_associative_math) SetByCombined
2033 Allow optimization for floating-point arithmetic which may change the
2034 result of the operation due to rounding.
2037 Common Report Var(flag_reciprocal_math) SetByCombined
2038 Same as -fassociative-math for expressions which include division.
2040 ; Nonzero means that unsafe floating-point math optimizations are allowed
2041 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2042 ; are allowed to assume that their arguments and results are "normal"
2043 ; (e.g., nonnegative for SQRT).
2044 funsafe-math-optimizations
2045 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2046 Allow math optimizations that may violate IEEE or ISO standards
2049 Common Report Var(flag_unswitch_loops) Optimization
2050 Perform loop unswitching
2053 Common Report Var(flag_unwind_tables) Optimization
2054 Just generate unwind tables for exception handling
2059 ; Positive if we should track variables, negative if we should run
2060 ; the var-tracking pass only to discard debug annotations, zero if
2061 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2062 ; will be set according to optimize, debug_info_level and debug_hooks
2063 ; in process_options ().
2065 Common Report Var(flag_var_tracking) Init(2) Optimization
2066 Perform variable tracking
2068 ; Positive if we should track variables at assignments, negative if
2069 ; we should run the var-tracking pass only to discard debug
2070 ; annotations. When flag_var_tracking_assignments ==
2071 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2072 fvar-tracking-assignments
2073 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2074 Perform variable tracking by annotating assignments
2076 ; Nonzero if we should toggle flag_var_tracking_assignments after
2077 ; processing options and computing its default. */
2078 fvar-tracking-assignments-toggle
2079 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2080 Toggle -fvar-tracking-assignments
2082 fvar-tracking-uninit
2083 Common Report Var(flag_var_tracking_uninit) Optimization
2084 Perform variable tracking and also tag variables that are uninitialized
2087 Common Report Var(flag_tree_vectorize) Optimization
2088 Enable loop vectorization on trees
2091 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2092 Enable basic block vectorization (SLP) on trees
2095 Common Report Var(flag_vect_cost_model) Optimization
2096 Enable use of cost model in vectorization
2098 ftree-vect-loop-version
2099 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2100 Enable loop versioning when doing loop vectorization on trees
2102 ftree-vectorizer-verbose=
2103 Common RejectNegative Joined UInteger
2104 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
2107 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2108 Enable copy propagation of scalar-evolution information.
2110 ; -fverbose-asm causes extra commentary information to be produced in
2111 ; the generated assembly code (to make it more readable). This option
2112 ; is generally only of use to those who actually need to read the
2113 ; generated assembly code (perhaps while debugging the compiler itself).
2114 ; -fno-verbose-asm, the default, causes the extra information
2115 ; to not be added and is useful when comparing two assembler files.
2117 Common Report Var(flag_verbose_asm)
2118 Add extra commentary to assembler output
2121 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2122 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2125 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2128 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2131 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2134 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2137 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2140 Common Report Var(flag_value_profile_transformations) Optimization
2141 Use expression value profiles in optimizations
2144 Common Report Var(flag_web) Init(2) Optimization
2145 Construct webs and split unrelated uses of single variable
2147 ftree-builtin-call-dce
2148 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2149 Enable conditional dead code elimination for builtin calls
2152 Common Report Var(flag_whole_program) Init(0) Optimization
2153 Perform whole program optimizations
2156 Common Report Var(flag_wrapv) Optimization
2157 Assume signed arithmetic overflow wraps around
2159 fzero-initialized-in-bss
2160 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2161 Put zero initialized data in the bss section
2164 Common JoinedOrMissing
2165 Generate debug information in default format
2168 Common JoinedOrMissing Negative(gdwarf-)
2169 Generate debug information in COFF format
2172 Common Joined UInteger Var(dwarf_version) Init(2) Negative(gstabs)
2173 Generate debug information in DWARF v2 (or later) format
2176 Common JoinedOrMissing
2177 Generate debug information in default extended format
2180 Common JoinedOrMissing Negative(gstabs+)
2181 Generate debug information in STABS format
2184 Common JoinedOrMissing Negative(gvms)
2185 Generate debug information in extended STABS format
2188 Common RejectNegative Var(dwarf_strict,0) Init(-1)
2189 Emit DWARF additions beyond selected version
2192 Common Report RejectNegative Var(dwarf_strict,1)
2193 Don't emit DWARF additions beyond selected version
2196 Common Report Var(flag_gtoggle)
2197 Toggle debug information generation
2200 Common JoinedOrMissing Negative(gxcoff)
2201 Generate debug information in VMS format
2204 Common JoinedOrMissing Negative(gxcoff+)
2205 Generate debug information in XCOFF format
2208 Common JoinedOrMissing Negative(gcoff)
2209 Generate debug information in extended XCOFF format
2212 Driver Joined Separate
2215 Common Joined Var(plugindir_string) Init(0)
2216 -iplugindir=<dir> Set <dir> to be the default plugin directory
2219 Driver Joined Separate
2224 no-canonical-prefixes
2240 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2241 -o <file> Place output into <file>
2244 Common Var(profile_flag)
2245 Enable function profiling
2248 Driver Var(pass_exit_codes)
2251 Common Var(pedantic)
2252 Issue warnings needed for strict compliance to the standard
2255 Common Var(flag_pedantic_errors)
2256 Like -pedantic but issue them as errors
2262 Driver Var(use_pipes)
2265 Driver JoinedOrMissing Var(print_file_name)
2267 print-libgcc-file-name
2270 print-multi-directory
2271 Driver Var(print_multi_directory)
2274 Driver Var(print_multi_lib)
2276 print-multi-os-directory
2277 Driver Var(print_multi_os_directory)
2280 Driver JoinedOrMissing Var(print_prog_name)
2283 Driver Var(print_search_dirs)
2286 Driver Var(print_sysroot)
2288 print-sysroot-headers-suffix
2289 Driver Var(print_sysroot_headers_suffix)
2292 Common Var(quiet_flag) RejectDriver
2293 Do not display functions compiled or elapsed time
2311 Driver Var(report_times)
2314 Driver JoinedOrMissing
2317 Driver Joined Separate
2321 ; C option, but driver must not handle as "-u ndef".
2324 Common Driver Var(verbose_flag)
2325 Enable verbose output
2328 Common Var(version_flag) RejectDriver
2329 Display the compiler's version
2332 Common Var(inhibit_warnings)
2336 Driver Separate Var(wrapper_string)
2339 Driver Joined Separate
2342 Common RejectNegative Negative(pie)
2343 Create a shared library
2349 Driver Separate Alias(specs=)
2362 ; Documented for Fortran, but always accepted by driver.
2369 ; Documented for Go, but always accepted by driver.
2375 Common RejectNegative Negative(shared)
2376 Create a position independent executable
2379 Driver Joined Separate
2381 ; This comment is to ensure we retain the blank line above.