1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003-2014 Free Software Foundation, Inc.
5 ; This file is part of GCC.
7 ; GCC is free software; you can redistribute it and/or modify it under
8 ; the terms of the GNU General Public License as published by the Free
9 ; Software Foundation; either version 3, or (at your option) any later
12 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 ; You should have received a copy of the GNU General Public License
18 ; along with GCC; see the file COPYING3. If not see
19 ; <http://www.gnu.org/licenses/>.
21 ; See the GCC internals manual (options.texi) for a description of this file's format.
23 ; Please try to keep this file in ASCII collating order.
37 ; Not used directly to control optimizations, only to save -Ofast
38 ; setting for "optimize" attributes.
42 ; True if this is the lto front end. This is used to disable gimple
43 ; generation and lowering passes that are normally run on the output
44 ; of a front end. These passes must be bypassed for lto since they
45 ; have already been done before the gimple was written.
49 ; 0 means straightforward implementation of complex divide acceptable.
50 ; 1 means wide ranges of inputs must work for complex divide.
51 ; 2 means C99-like requirements for complex multiply and divide.
53 int flag_complex_method = 1
55 ; Nonzero if subexpressions must be evaluated from left-to-right.
57 int flag_evaluation_order = 0
59 ; Language specific warning pass for unused results.
61 bool flag_warn_unused_result = false
66 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
70 ; True to warn about any objects definitions whose size is larger
71 ; than N bytes. Also want about function definitions whose returned
72 ; values are larger than N bytes, where N is 'larger_than_size'.
77 HOST_WIDE_INT larger_than_size
79 ; True to warn about any function whose frame size is larger
82 bool warn_frame_larger_than
85 HOST_WIDE_INT frame_larger_than_size
87 ; Nonzero means we should be saving declaration info into a .X file.
89 int flag_gen_aux_info = 0
91 ; Nonzero if we are compiling code for a shared library, zero for
96 ; These two are really VEC(char_p,heap) *.
99 void *flag_instrument_functions_exclude_functions
102 void *flag_instrument_functions_exclude_files
104 ; Generic structs (e.g. templates not explicitly specialized)
105 ; may not have a compilation unit associated with them, and so
106 ; may need to be treated differently from ordinary structs.
108 ; Structs only handled by reference (indirectly), will also usually
109 ; not need as much debugging information.
112 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
115 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
117 ; True if we should exit after parsing options.
119 bool exit_after_options
121 ; Type(s) of debugging information we are producing (if any). See
122 ; flag-types.h for the definitions of the different possible types of
123 ; debugging information.
125 enum debug_info_type write_symbols = NO_DEBUG
127 ; Level of debugging information we are producing. See flag-types.h
128 ; for the definitions of the different possible levels.
130 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
132 ; Nonzero means use GNU-only extensions in the generated symbolic
133 ; debugging information. Currently, this only has an effect when
134 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
136 bool use_gnu_debug_info_extensions
138 ; Original value of maximum field alignment in bytes, specified via
139 ; -fpack-struct=<value>.
141 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
143 ; Type of stack check.
145 enum stack_check_type flag_stack_check = NO_STACK_CHECK
147 ; True if stack usage information needs to be computed.
149 bool flag_stack_usage_info = false
151 ; -dA causes debug commentary information to be produced in
152 ; the generated assembly code (to make it more readable). This option
153 ; is generally only of use to those who actually need to read the
154 ; generated assembly code (perhaps while debugging the compiler itself).
155 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
156 ; to be a catchall for printing debug information in the assembler file.
160 ; -dP causes the rtl to be emitted as a comment in assembly.
162 int flag_dump_rtl_in_asm
164 ; Whether -da was passed (used only in handle_common_deferred_options).
166 bool flag_dump_all_passed
168 ; Other flags saying which kinds of debugging dump have been requested.
171 int rtl_dump_and_exit
174 int flag_print_asm_name
176 ; Name of top-level original source file (what was input to cpp).
177 ; This comes from the #-command at the beginning of the actual input.
178 ; If there isn't any there, then this is the cc1 input file name.
180 const char *main_input_filename
182 ; Pointer to base name in main_input_filename, with directories and a
183 ; single final extension removed, and the length of this base
187 const char *main_input_basename
190 int main_input_baselength
192 ; Which options have been printed by --help.
196 ; Which enums have been printed by --help. 0 = not printed, no
197 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
200 char *help_enum_printed
202 ; The number of columns for --help output.
204 unsigned int help_columns
206 ; Whether this options structure has been through finish_options
208 bool flag_opts_finished
210 ; What the sanitizer should instrument
212 unsigned int flag_sanitize
214 ; Flag whether a prefix has been added to dump_base_name
216 bool dump_base_name_prefixed = false
228 Driver Alias(coverage)
234 Common Separate Alias(d)
237 Common Joined Alias(d)
240 Common Separate Alias(dumpbase)
243 Common Separate Alias(dumpdir)
246 Driver Separate Alias(e)
249 Driver Joined Alias(e)
252 Common Warning Alias(Wextra)
255 Driver Separate Alias(Xassembler)
258 Driver JoinedOrMissing Alias(Xassembler)
261 Driver Separate Alias(Xlinker)
264 Driver JoinedOrMissing Alias(Xlinker)
267 Driver Separate Alias(u)
270 Driver Joined Alias(u)
273 Common Driver Var(help_flag)
274 Display this information
277 Common Driver Report Joined
278 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
281 Driver Separate Alias(x)
284 Driver Joined Alias(x)
287 Driver Separate Alias(L)
290 Driver Joined Alias(L)
292 -no-canonical-prefixes
293 Driver Alias(no-canonical-prefixes)
295 -no-standard-libraries
296 Driver Alias(nostdlib)
299 Driver Var(no_sysroot_suffix)
308 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
311 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
314 Driver Alias(pass-exit-codes)
317 Common Alias(Wpedantic)
320 Common Alias(pedantic-errors)
329 Driver Separate Alias(B)
332 Driver JoinedOrMissing Alias(B)
338 Driver Separate Alias(print-file-name=)
341 Driver JoinedOrMissing Alias(print-file-name=)
343 -print-libgcc-file-name
344 Driver Alias(print-libgcc-file-name)
346 -print-multi-directory
347 Driver Alias(print-multi-directory)
350 Driver Alias(print-multi-lib)
352 -print-multi-os-directory
353 Driver Alias(print-multi-os-directory)
356 Driver Alias(print-multiarch)
359 Driver Separate Alias(print-prog-name=)
362 Driver JoinedOrMissing Alias(print-prog-name=)
365 Driver Alias(print-search-dirs)
368 Driver Alias(print-sysroot)
370 -print-sysroot-headers-suffix
371 Driver Alias(print-sysroot-headers-suffix)
377 Driver Alias(save-temps)
383 Driver Separate Alias(specs=)
386 Driver Joined Alias(specs=)
392 Driver Alias(symbolic)
396 Alias for --help=target
404 ;; The driver used to convert options such as --help into forms such
405 ;; as -fhelp; the following four entries are for compatibility with
406 ;; any direct uses of those (undocumented) -f forms
408 Common Driver Alias(-help)
411 Common Driver Joined Alias(-help=)
414 Common Driver Alias(-target-help)
417 Common Driver Alias(-version)
421 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
424 Common Joined Alias(-param)
427 Driver Separate Alias(-sysroot=)
430 Driver JoinedOrMissing
436 Driver Joined Separate
442 Driver Joined Separate
448 Common JoinedOrMissing Optimization
449 -O<number> Set optimization level to <number>
453 Optimize for space rather than speed
457 Optimize for speed disregarding exact standards compliance
461 Optimize for debugging experience rather than speed or size
473 Driver Joined Separate
479 Driver Joined Separate
500 Common RejectNegative Warning Alias(Wextra)
501 This switch is deprecated; use -Wextra instead
504 Driver JoinedOrMissing
507 Driver JoinedOrMissing
510 Driver JoinedOrMissing
513 Common Var(warn_aggregate_return) Warning
514 Warn about returning structures, unions or arrays
516 Waggressive-loop-optimizations
517 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
518 Warn if a loop with constant number of iterations triggers undefined behavior
521 Common Var(warn_array_bounds) Warning
522 Warn if an array is accessed out of bounds
525 Common Var(warn_attributes) Init(1) Warning
526 Warn about inappropriate attribute usage
529 Common Var(warn_cast_align) Warning
530 Warn about pointer casts which increase alignment
533 Common Var(warn_cpp) Init(1) Warning
534 Warn when a #warning directive is encountered
536 Wdeprecated-declarations
537 Common Var(warn_deprecated_decl) Init(1) Warning
538 Warn about uses of __attribute__((deprecated)) declarations
540 Wdisabled-optimization
541 Common Var(warn_disabled_optimization) Warning
542 Warn when an optimization pass is disabled
545 Common Var(warnings_are_errors)
546 Treat all warnings as errors
550 Treat specified warning as error
553 Common Var(extra_warnings) Warning
554 Print extra (possibly unwanted) warnings
557 Common Var(flag_fatal_errors)
558 Exit on the first error occurred
561 Common RejectNegative Joined UInteger
562 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
565 Common Var(warn_free_nonheap_object) Init(1) Warning
566 Warn when attempting to free a non-heap object
569 Common Var(warn_inline) Warning
570 Warn when an inlined function cannot be inlined
572 Winvalid-memory-model
573 Common Var(warn_invalid_memory_model) Init(1) Warning
574 Warn when an atomic memory model parameter is known to be outside the valid range.
577 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
580 Common RejectNegative Joined UInteger Warning
581 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
583 Wunsafe-loop-optimizations
584 Common Var(warn_unsafe_loop_optimizations) Warning
585 Warn if the loop cannot be optimized due to nontrivial assumptions.
588 Common Alias(Wsuggest-attribute=noreturn)
591 Common Var(warn_overflow) Init(1) Warning
592 Warn about overflow in arithmetic expressions
595 Common Var(warn_packed) Warning
596 Warn when the packed attribute has no effect on struct layout
599 Common Var(warn_padded) Warning
600 Warn when padding is required to align structure members
603 Common Var(pedantic) Warning
604 Issue warnings needed for strict compliance to the standard
607 Common Var(warn_shadow) Warning
608 Warn when one local variable shadows another
611 Common Var(warn_stack_protect) Warning
612 Warn when not issuing stack smashing protection for some reason
615 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
616 Warn if stack usage might be larger than specified amount
620 Warn about code which might break strict aliasing rules
623 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
624 Warn about code which might break strict aliasing rules
628 Warn about optimizations that assume that signed overflow is undefined
631 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
632 Warn about optimizations that assume that signed overflow is undefined
634 Wsuggest-attribute=const
635 Common Var(warn_suggest_attribute_const) Warning
636 Warn about functions which might be candidates for __attribute__((const))
638 Wsuggest-attribute=pure
639 Common Var(warn_suggest_attribute_pure) Warning
640 Warn about functions which might be candidates for __attribute__((pure))
642 Wsuggest-attribute=noreturn
643 Common Var(warn_suggest_attribute_noreturn) Warning
644 Warn about functions which might be candidates for __attribute__((noreturn))
647 Common Var(warn_system_headers) Warning
648 Do not suppress warnings from system headers
651 Common Var(warn_trampolines) Warning
652 Warn whenever a trampoline is generated
655 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
656 Warn if a comparison is always true or always false due to the limited range of the data type
659 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
660 Warn about uninitialized automatic variables
663 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
664 Warn about maybe uninitialized automatic variables
668 Does nothing. Preserved for backward compatibility.
671 Common Var(warn_unused) Init(0) Warning
672 Enable all -Wunused- warnings
674 Wunused-but-set-parameter
675 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
676 Warn when a function parameter is only set, otherwise unused
678 Wunused-but-set-variable
679 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
680 Warn when a variable is only set, otherwise unused
683 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
684 Warn when a function is unused
687 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
688 Warn when a label is unused
691 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
692 Warn when a function parameter is unused
695 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
696 Warn when an expression value is unused
699 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
700 Warn when a variable is unused
703 Common Var(warn_coverage_mismatch) Init(1) Warning
704 Warn in case profiles in -fprofile-use do not match
706 Wvector-operation-performance
707 Common Var(warn_vector_operation_performance) Warning
708 Warn when a vector operation is compiled outside the SIMD
723 Common Separate Var(aux_info_file_name)
724 -aux-info <file> Emit declaration information into <file>
727 Common Joined Alias(aux-info)
730 Common Separate RejectDriver Var(aux_base_name)
733 Common Separate RejectDriver
743 -d<letters> Enable dumps from specific passes of the compiler
746 Common Separate Var(dump_base_name)
747 -dumpbase <file> Set the file basename to be used for dumps
750 Common Separate Var(dump_dir_name)
751 -dumpdir <dir> Set the directory name to be used for dumps
763 Driver Joined Separate
765 ; This option has historically been passed down to the linker by an
766 ; accident of a %{e*} spec, so ensure it continues to be passed down
767 ; as a single option. The supported option for this purpose is
768 ; -rdynamic. See PR 47390.
772 ; The version of the C++ ABI in use. The following values are allowed:
774 ; 0: The version of the ABI believed most conformant with the C++ ABI
775 ; specification. This ABI may change as bugs are discovered and fixed.
776 ; Therefore, 0 will not necessarily indicate the same ABI in different
779 ; 1: The version of the ABI first used in G++ 3.2.
781 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
783 ; 3: The version of the ABI that fixes the missing underscore
784 ; in template non-type arguments of pointer type.
786 ; 4: The version of the ABI that introduces unambiguous mangling of
787 ; vector types. First selectable in G++ 4.5.
789 ; 5: The version of the ABI that ignores attribute const/noreturn
790 ; in function pointer mangling, and corrects mangling of decltype and
791 ; function parameters used in other parameters and the return type.
792 ; First selectable in G++ 4.6.
794 ; 6: The version of the ABI that doesn't promote scoped enums to int and
795 ; changes the mangling of template argument packs, const/static_cast,
796 ; prefix ++ and --, and a class scope function used as a template
798 ; First selectable in G++ 4.7.
800 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
801 ; corrects the mangling of lambdas in default argument scope.
802 ; First selectable in G++ 4.8.
804 ; 8: The version of the ABI that corrects the substitution behavior of
805 ; function types with function-cv-qualifiers.
806 ; First selectable in G++ 4.9.
808 ; Additional positive integers will be assigned as new versions of
809 ; the ABI become the default version of the ABI.
811 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
813 faggressive-loop-optimizations
814 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
815 Aggressively optimize loops using language constraints
818 Common Report Var(align_functions,0) Optimization UInteger
819 Align the start of functions
822 Common RejectNegative Joined UInteger Var(align_functions)
825 Common Report Var(align_jumps,0) Optimization UInteger
826 Align labels which are only reached by jumping
829 Common RejectNegative Joined UInteger Var(align_jumps)
832 Common Report Var(align_labels,0) Optimization UInteger
836 Common RejectNegative Joined UInteger Var(align_labels)
839 Common Report Var(align_loops,0) Optimization UInteger
840 Align the start of loops
843 Common RejectNegative Joined UInteger Var(align_loops)
847 Does nothing. Preserved for backward compatibility.
851 Does nothing. Preserved for backward compatibility.
853 fargument-noalias-global
855 Does nothing. Preserved for backward compatibility.
857 fargument-noalias-anything
859 Does nothing. Preserved for backward compatibility.
862 Common Driver Report Joined
863 Select what to sanitize
866 Common Report Var(flag_sanitize_recover) Init(1)
867 After diagnosing undefined behavior attempt to continue execution
869 fsanitize-undefined-trap-on-error
870 Common Report Var(flag_sanitize_undefined_trap_on_error) Init(0)
871 Use trap instead of a library function for undefined behavior sanitization
873 fasynchronous-unwind-tables
874 Common Report Var(flag_asynchronous_unwind_tables) Optimization
875 Generate unwind tables that are exact at each instruction boundary
878 Common Report Var(flag_auto_inc_dec) Init(1)
879 Generate auto-inc/dec instructions
881 ; -fcheck-bounds causes gcc to generate array bounds checks.
882 ; For C, C++ and ObjC: defaults off.
883 ; For Java: defaults to on.
884 ; For Fortran: defaults to off.
886 Common Report Var(flag_bounds_check)
887 Generate code to check bounds before indexing arrays
890 Common Report Var(flag_branch_on_count_reg) Optimization
891 Replace add, compare, branch with branch on count register
893 fbranch-probabilities
894 Common Report Var(flag_branch_probabilities) Optimization
895 Use profiling information for branch probabilities
897 fbranch-target-load-optimize
898 Common Report Var(flag_branch_target_load_optimize) Optimization
899 Perform branch target load optimization before prologue / epilogue threading
901 fbranch-target-load-optimize2
902 Common Report Var(flag_branch_target_load_optimize2) Optimization
903 Perform branch target load optimization after prologue / epilogue threading
906 Common Report Var(flag_btr_bb_exclusive) Optimization
907 Restrict target load migration not to re-use registers in any basic block
910 Common Joined RejectNegative Var(common_deferred_options) Defer
911 -fcall-saved-<register> Mark <register> as being preserved across functions
914 Common Joined RejectNegative Var(common_deferred_options) Defer
915 -fcall-used-<register> Mark <register> as being corrupted by function calls
917 ; Nonzero for -fcaller-saves: allocate values in regs that need to
918 ; be saved across function calls, if that produces overall better code.
919 ; Optional now, so people can test it.
921 Common Report Var(flag_caller_saves) Optimization
922 Save registers around function calls
925 Common Report Var(flag_check_data_deps)
926 Compare the results of several data dependence analyzers.
929 Common Var(flag_check_new)
930 Check the return value of new in C++
932 fcombine-stack-adjustments
933 Common Report Var(flag_combine_stack_adjustments) Optimization
934 Looks for opportunities to reduce stack adjustments and stack references.
937 Common Report Var(flag_no_common,0) Optimization
938 Do not put uninitialized globals in the common section
942 ; Converted by the driver to -fcompare-debug= options.
945 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
946 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
948 fcompare-debug-second
949 Common Driver RejectNegative Var(flag_compare_debug)
950 Run only the second compilation of -fcompare-debug
953 Common Report Var(flag_compare_elim_after_reload) Optimization
954 Perform comparison elimination after register allocation has finished
957 Common Var(flag_conserve_stack) Optimization
958 Do not perform optimizations increasing noticeably stack usage
961 Common Report Var(flag_cprop_registers) Optimization
962 Perform a register copy-propagation optimization pass
965 Common Report Var(flag_crossjumping) Optimization
966 Perform cross-jumping optimization
969 Common Report Var(flag_cse_follow_jumps) Optimization
970 When running CSE, follow jumps to their targets
974 Does nothing. Preserved for backward compatibility.
977 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
978 Omit range reduction step when performing complex division
981 Common Report Var(flag_cx_fortran_rules) Optimization
982 Complex multiplication and division follow Fortran rules
985 Common Report Var(flag_data_sections) Optimization
986 Place data items into their own section
989 Common Report Var(common_deferred_options) Defer
990 List all available debugging counters with their limits and counts.
993 Common RejectNegative Joined Var(common_deferred_options) Defer
994 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
997 Common Joined RejectNegative Var(common_deferred_options) Defer
998 Map one directory name to another in debug information
1000 fdebug-types-section
1001 Common Report Var(flag_debug_types_section) Init(0)
1002 Output .debug_types section when using DWARF v4 debuginfo.
1004 ; Nonzero for -fdefer-pop: don't pop args after each function call
1005 ; instead save them up to pop many calls' args with one insns.
1007 Common Report Var(flag_defer_pop) Optimization
1008 Defer popping functions args from stack until later
1011 Common Report Var(flag_delayed_branch) Optimization
1012 Attempt to fill delay slots of branch instructions
1014 fdelete-dead-exceptions
1015 Common Report Var(flag_delete_dead_exceptions) Init(0)
1016 Delete dead instructions that may throw exceptions
1018 fdelete-null-pointer-checks
1019 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
1020 Delete useless null pointer checks
1022 fdevirtualize-speculatively
1023 Common Report Var(flag_devirtualize_speculatively) Optimization
1024 Perform speculative devirtualization
1027 Common Report Var(flag_devirtualize) Optimization
1028 Try to convert virtual calls to direct ones.
1030 fdiagnostics-show-location=
1031 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1032 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
1034 ; Required for these enum values.
1039 Name(diagnostic_prefixing_rule) Type(int)
1042 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1045 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1047 fdiagnostics-show-caret
1048 Common Var(flag_diagnostics_show_caret) Init(1)
1049 Show the source line with a caret indicating the column
1052 Common Alias(fdiagnostics-color=,always,never)
1056 Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1057 -fdiagnostics-color=[never|always|auto] Colorize diagnostics
1059 ; Required for these enum values.
1064 Name(diagnostic_color_rule) Type(int)
1067 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1070 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1073 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1075 fdiagnostics-show-option
1076 Common Var(flag_diagnostics_show_option) Init(1)
1077 Amend appropriate diagnostic messages with the command line option that controls them
1080 Common Joined RejectNegative Var(common_deferred_options) Defer
1081 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1084 Common Joined RejectNegative Var(common_deferred_options) Defer
1085 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1088 Common Joined RejectNegative Var(common_deferred_options) Defer
1089 -fdump-<type> Dump various compiler internals to a file
1092 Driver RejectNegative
1095 Common RejectNegative Joined Var(flag_dump_final_insns)
1096 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1099 Common RejectNegative Joined Var(flag_dump_go_spec)
1100 -fdump-go-spec=filename Write all declarations to file as Go code
1103 Common Report Var(flag_dump_noaddr)
1104 Suppress output of addresses in debugging dumps
1107 Common Var(flag_dump_passes) Init(0)
1108 Dump optimization passes
1111 Common Report Var(flag_dump_unnumbered)
1112 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1114 fdump-unnumbered-links
1115 Common Report Var(flag_dump_unnumbered_links)
1116 Suppress output of previous and next insn numbers in debugging dumps
1119 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1120 Enable CFI tables via GAS assembler directives.
1123 Common Report Var(flag_early_inlining) Init(1) Optimization
1124 Perform early inlining
1126 feliminate-dwarf2-dups
1127 Common Report Var(flag_eliminate_dwarf2_dups)
1128 Perform DWARF2 duplicate elimination
1131 Common Report Var(flag_ipa_sra) Init(0) Optimization
1132 Perform interprocedural reduction of aggregates
1134 feliminate-unused-debug-symbols
1135 Common Report Var(flag_debug_only_used_symbols)
1136 Perform unused type elimination in debug info
1138 feliminate-unused-debug-types
1139 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1140 Perform unused type elimination in debug info
1142 femit-class-debug-always
1143 Common Report Var(flag_emit_class_debug_always) Init(0)
1144 Do not suppress C++ class debug information.
1147 Common Report Var(flag_exceptions) Optimization
1148 Enable exception handling
1150 fexpensive-optimizations
1151 Common Report Var(flag_expensive_optimizations) Optimization
1152 Perform a number of minor, expensive optimizations
1155 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1156 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1159 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1162 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1165 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1171 Common Var(flag_fat_lto_objects)
1172 Output lto objects containing both the intermediate language and binary output.
1175 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1176 Assume no NaNs or infinities are generated
1179 Common Joined RejectNegative Var(common_deferred_options) Defer
1180 -ffixed-<register> Mark <register> as being unavailable to the compiler
1183 Common Report Var(flag_float_store) Optimization
1184 Don't allocate floats and doubles in extended-precision registers
1188 Does nothing. Preserved for backward compatibility.
1191 Common Report Var(flag_forward_propagate) Optimization
1192 Perform a forward propagation pass on RTL
1195 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1196 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1199 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1202 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1204 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1206 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1209 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1211 ; Nonzero means don't put addresses of constant functions in registers.
1212 ; Used for compiling the Unix kernel, where strange substitutions are
1213 ; done on the assembly output.
1215 Common Report Var(flag_no_function_cse,0)
1216 Allow function addresses to be held in registers
1219 Common Report Var(flag_function_sections)
1220 Place each function into its own section
1223 Common Report Var(flag_gcse) Optimization
1224 Perform global common subexpression elimination
1227 Common Report Var(flag_gcse_lm) Init(1) Optimization
1228 Perform enhanced load motion during global common subexpression elimination
1231 Common Report Var(flag_gcse_sm) Init(0) Optimization
1232 Perform store motion after global common subexpression elimination
1235 Common Report Var(flag_gcse_las) Init(0) Optimization
1236 Perform redundant load after store elimination in global common subexpression
1240 Common Report Var(flag_gcse_after_reload) Optimization
1241 Perform global common subexpression elimination after register allocation
1244 ; This option is not documented yet as its semantics will change.
1246 Common Report Var(flag_graphite)
1247 Enable in and out of Graphite representation
1250 Common Report Var(flag_graphite_identity) Optimization
1251 Enable Graphite Identity transformation
1253 fhoist-adjacent-loads
1254 Common Report Var(flag_hoist_adjacent_loads) Optimization
1255 Enable hoisting adjacent loads to encourage generating conditional move
1258 floop-parallelize-all
1259 Common Report Var(flag_loop_parallelize_all) Optimization
1260 Mark all loops as parallel
1263 Common Report Var(flag_loop_strip_mine) Optimization
1264 Enable Loop Strip Mining transformation
1267 Common Report Var(flag_loop_interchange) Optimization
1268 Enable Loop Interchange transformation
1271 Common Report Var(flag_loop_block) Optimization
1272 Enable Loop Blocking transformation
1275 Common Report Var(flag_tm)
1276 Enable support for GNU transactional memory
1279 Common Report Var(flag_gnu_unique) Init(1)
1280 Use STB_GNU_UNIQUE if supported by the assembler
1284 Does nothing. Preserved for backward compatibility.
1287 Common Report Var(flag_loop_optimize_isl) Optimization
1288 Enable the ISL based loop nest optimizer
1290 fstrict-volatile-bitfields
1291 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1292 Force bitfield accesses to match their type width
1294 fguess-branch-probability
1295 Common Report Var(flag_guess_branch_prob) Optimization
1296 Enable guessing of branch probabilities
1298 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1299 ; Generate position-independent code for executables if possible
1300 ; On SVR4 targets, it also controls whether or not to emit a
1301 ; string identifying the compiler.
1303 Common Report Var(flag_no_ident,0)
1304 Process #ident directives
1307 Common Report Var(flag_if_conversion) Optimization
1308 Perform conversion of conditional jumps to branchless equivalents
1311 Common Report Var(flag_if_conversion2) Optimization
1312 Perform conversion of conditional jumps to conditional execution
1315 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL)
1316 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1319 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1322 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1325 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1328 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1330 ftree-loop-if-convert
1331 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1332 Convert conditional jumps in innermost loops to branchless equivalents
1334 ftree-loop-if-convert-stores
1335 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1336 Also if-convert conditional jumps containing memory writes
1338 ; -finhibit-size-directive inhibits output of .size for ELF.
1339 ; This is used only for compiling crtstuff.c,
1340 ; and it may be extended to other effects
1341 ; needed for crtstuff.c on other systems.
1342 finhibit-size-directive
1343 Common Report Var(flag_inhibit_size_directive)
1344 Do not generate .size directives
1347 Common Report Var(flag_indirect_inlining)
1348 Perform indirect inlining
1350 ; General flag to enable inlining. Specifying -fno-inline will disable
1351 ; all inlining apart from always-inline functions.
1353 Common Report Var(flag_no_inline,0) Init(0) Optimization
1354 Enable inlining of function declared \"inline\", disabling disables all inlining
1356 finline-small-functions
1357 Common Report Var(flag_inline_small_functions) Optimization
1358 Integrate functions into their callers when code size is known not to grow
1361 Common Report Var(flag_inline_functions) Optimization
1362 Integrate functions not declared \"inline\" into their callers when profitable
1364 finline-functions-called-once
1365 Common Report Var(flag_inline_functions_called_once) Optimization
1366 Integrate functions only required by their single caller
1369 Common RejectNegative Joined Alias(finline-limit=)
1372 Common RejectNegative Joined UInteger
1373 -finline-limit=<number> Limit the size of inlined functions to <number>
1376 Common Report Var(flag_inline_atomics) Init(1) Optimization
1377 Inline __atomic operations when a lock free instruction sequence is available.
1379 finstrument-functions
1380 Common Report Var(flag_instrument_function_entry_exit)
1381 Instrument function entry and exit with profiling calls
1383 finstrument-functions-exclude-function-list=
1384 Common RejectNegative Joined
1385 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1387 finstrument-functions-exclude-file-list=
1388 Common RejectNegative Joined
1389 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1392 Common Report Var(flag_ipa_cp) Optimization
1393 Perform interprocedural constant propagation
1396 Common Report Var(flag_ipa_cp_clone) Optimization
1397 Perform cloning to make Interprocedural constant propagation stronger
1400 Common Report Var(flag_ipa_profile) Init(0) Optimization
1401 Perform interprocedural profile propagation
1404 Common Report Var(flag_ipa_pta) Init(0) Optimization
1405 Perform interprocedural points-to analysis
1408 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1409 Discover pure and const functions
1412 Common Report Var(flag_ipa_reference) Init(0) Optimization
1413 Discover readonly and non addressable static variables
1417 Does nothing. Preserved for backward compatibility.
1421 Does nothing. Preserved for backward compatibility.
1424 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1425 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1428 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1431 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1434 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1437 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1438 -fira-region=[one|all|mixed] Set regions for IRA
1441 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1444 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1447 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1450 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1453 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1454 Use IRA based register pressure calculation
1455 in RTL hoist optimizations.
1458 Common Report Var(flag_ira_loop_pressure) Optimization
1459 Use IRA based register pressure calculation
1460 in RTL loop optimizations.
1462 fira-share-save-slots
1463 Common Report Var(flag_ira_share_save_slots) Init(1)
1464 Share slots for saving different hard registers.
1466 fira-share-spill-slots
1467 Common Report Var(flag_ira_share_spill_slots) Init(1)
1468 Share stack slots for spilled pseudo-registers.
1471 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1472 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1475 Common Report Var(flag_ivopts) Init(1) Optimization
1476 Optimize induction variables on trees
1479 Common Var(flag_jump_tables) Init(1) Optimization
1480 Use jump tables for sufficiently large switch statements
1482 fkeep-inline-functions
1483 Common Report Var(flag_keep_inline_functions)
1484 Generate code for functions even if they are fully inlined
1487 Common Report Var(flag_keep_static_consts) Init(1)
1488 Emit static const variables even if they are not used
1491 Common Report Var(flag_leading_underscore) Init(-1)
1492 Give external symbols a leading underscore
1496 Does nothing. Preserved for backward compatibility.
1500 Enable link-time optimization.
1503 Common RejectNegative Joined Var(flag_lto)
1504 Link-time optimization with number of parallel jobs or jobserver.
1507 Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
1510 Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
1513 Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
1516 Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
1519 Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
1522 Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
1525 Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)
1526 Specify the algorithm to partition symbols and vars at linktime
1528 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1529 flto-compression-level=
1530 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1531 -flto-compression-level=<number> Use zlib compression level <number> for IL
1534 Common Report Var(flag_lto_report) Init(0)
1535 Report various link-time optimization statistics
1538 Common Report Var(flag_lto_report_wpa) Init(0)
1539 Report various link-time optimization statistics for WPA only
1542 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1543 Set errno after built-in math functions
1546 Common Joined RejectNegative UInteger Var(flag_max_errors)
1547 -fmax-errors=<number> Maximum number of errors to report
1550 Common Report Var(mem_report)
1551 Report on permanent memory allocation
1554 Common Report Var(mem_report_wpa)
1555 Report on permanent memory allocation in WPA only
1557 ; This will attempt to merge constant section constants, if 1 only
1558 ; string constants and constants from constant pool, if 2 also constant
1560 fmerge-all-constants
1561 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1562 Attempt to merge identical constants and constant variables
1565 Common Report Var(flag_merge_constants,1) Optimization
1566 Attempt to merge identical constants across compilation units
1568 fmerge-debug-strings
1569 Common Report Var(flag_merge_debug_strings) Init(1)
1570 Attempt to merge identical debug strings across compilation units
1573 Common RejectNegative Joined UInteger
1574 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1577 Common Report Var(flag_modulo_sched) Optimization
1578 Perform SMS based modulo scheduling before the first scheduling pass
1580 fmodulo-sched-allow-regmoves
1581 Common Report Var(flag_modulo_sched_allow_regmoves)
1582 Perform SMS based modulo scheduling with register moves allowed
1584 fmove-loop-invariants
1585 Common Report Var(flag_move_loop_invariants) Optimization
1586 Move loop invariant computations out of loops
1589 Common Var(flag_dce) Init(1) Optimization
1590 Use the RTL dead code elimination pass
1593 Common Var(flag_dse) Init(1) Optimization
1594 Use the RTL dead store elimination pass
1596 freschedule-modulo-scheduled-loops
1597 Common Report Var(flag_resched_modulo_sched) Optimization
1598 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1600 fnon-call-exceptions
1601 Common Report Var(flag_non_call_exceptions) Optimization
1602 Support synchronous non-call exceptions
1605 Common Report Var(flag_omit_frame_pointer) Optimization
1606 When possible do not generate stack frames
1609 Common Report Var(flag_opt_info) Optimization
1610 Enable all optimization info dumps on stderr
1613 Common Joined RejectNegative Var(common_deferred_options) Defer
1614 -fopt-info[-<type>=filename] Dump compiler optimization details
1616 foptimize-register-move
1618 Does nothing. Preserved for backward compatibility.
1620 foptimize-sibling-calls
1621 Common Report Var(flag_optimize_sibling_calls) Optimization
1622 Optimize sibling and tail recursive calls
1625 Common Report Var(flag_partial_inlining)
1626 Perform partial inlining
1629 Common Report Var(pre_ipa_mem_report)
1630 Report on memory allocation before interprocedural optimization
1632 fpost-ipa-mem-report
1633 Common Report Var(post_ipa_mem_report)
1634 Report on memory allocation before interprocedural optimization
1637 Common Report Var(flag_pack_struct) Optimization
1638 Pack structure members together without holes
1641 Common RejectNegative Joined UInteger Optimization
1642 -fpack-struct=<number> Set initial maximum structure member alignment
1645 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1646 Return small aggregates in memory, not registers
1649 Common Report Var(flag_peel_loops) Optimization
1650 Perform loop peeling
1653 Common Report Var(flag_no_peephole,0) Optimization
1654 Enable machine specific peephole optimizations
1657 Common Report Var(flag_peephole2) Optimization
1658 Enable an RTL peephole pass before sched2
1661 Common Report Var(flag_pic,2) Negative(fPIE)
1662 Generate position-independent code if possible (large mode)
1665 Common Report Var(flag_pie,2) Negative(fpic)
1666 Generate position-independent code for executables if possible (large mode)
1669 Common Report Var(flag_pic,1) Negative(fpie)
1670 Generate position-independent code if possible (small mode)
1673 Common Report Var(flag_pie,1) Negative(fPIC)
1674 Generate position-independent code for executables if possible (small mode)
1677 Common Joined RejectNegative Var(common_deferred_options) Defer
1678 Specify a plugin to load
1681 Common Joined RejectNegative Var(common_deferred_options) Defer
1682 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1684 fpredictive-commoning
1685 Common Report Var(flag_predictive_commoning) Optimization
1686 Run predictive commoning optimization.
1688 fprefetch-loop-arrays
1689 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1690 Generate prefetch instructions, if available, for arrays in loops
1693 Common Report Var(profile_flag)
1694 Enable basic program profiling code
1697 Common Report Var(profile_arc_flag)
1698 Insert arc-based program profiling code
1701 Common Joined RejectNegative Var(profile_data_prefix)
1702 Set the top-level directory for storing the profile data.
1703 The default is 'pwd'.
1706 Common Report Var(flag_profile_correction)
1707 Enable correction of flow inconsistent profile data input
1711 Enable common options for generating profile info for profile feedback directed optimizations
1714 Common Joined RejectNegative
1715 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1718 Common Var(flag_profile_use)
1719 Enable common options for performing profile feedback directed optimizations
1722 Common Joined RejectNegative
1723 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1726 Common Report Var(flag_profile_values)
1727 Insert code to profile values of expressions
1730 Common Report Var(profile_report)
1731 Report on consistency of profile
1733 fprofile-reorder-functions
1734 Common Report Var(flag_profile_reorder_functions)
1735 Enable function reordering that improves code placement
1738 Common Var(common_deferred_options) Defer
1741 Common Joined RejectNegative Var(common_deferred_options) Defer
1742 -frandom-seed=<string> Make compile reproducible using <string>
1744 ; This switch causes the command line that was used to create an
1745 ; object file to be recorded into the object file. The exact format
1746 ; of this recording is target and binary file format dependent.
1747 ; It is related to the -fverbose-asm switch, but that switch only
1748 ; records information in the assembler output file as comments, so
1749 ; they never reach the object file.
1750 frecord-gcc-switches
1751 Common Report Var(flag_record_gcc_switches)
1752 Record gcc command line switches in the object file.
1755 Common Report Var(flag_pcc_struct_return,0) Optimization
1756 Return small aggregates in registers
1760 Does nothing. Preserved for backward compatibility.
1762 flive-range-shrinkage
1763 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
1764 Relief of register pressure through live range shrinkage
1767 Common Report Var(flag_rename_registers) Init(2) Optimization
1768 Perform a register renaming optimization pass
1771 Common Report Var(flag_reorder_blocks) Optimization
1772 Reorder basic blocks to improve code placement
1774 freorder-blocks-and-partition
1775 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1776 Reorder basic blocks and partition into hot and cold sections
1779 Common Report Var(flag_reorder_functions) Optimization
1780 Reorder functions to improve code placement
1782 frerun-cse-after-loop
1783 Common Report Var(flag_rerun_cse_after_loop) Optimization
1784 Add a common subexpression elimination pass after loop optimizations
1788 Does nothing. Preserved for backward compatibility.
1791 Common Report Var(flag_rounding_math) Optimization SetByCombined
1792 Disable optimizations that assume default FP rounding behavior
1795 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1796 Enable scheduling across basic blocks
1799 Common Report Var(flag_sched_pressure) Init(0) Optimization
1800 Enable register pressure sensitive insn scheduling
1803 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1804 Allow speculative motion of non-loads
1807 Common Report Var(flag_schedule_speculative_load) Optimization
1808 Allow speculative motion of some loads
1810 fsched-spec-load-dangerous
1811 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1812 Allow speculative motion of more loads
1815 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1816 -fsched-verbose=<number> Set the verbosity level of the scheduler
1818 fsched2-use-superblocks
1819 Common Report Var(flag_sched2_use_superblocks) Optimization
1820 If scheduling post reload, do superblock scheduling
1824 Does nothing. Preserved for backward compatibility.
1827 Common Report Var(flag_schedule_insns) Optimization
1828 Reschedule instructions before register allocation
1831 Common Report Var(flag_schedule_insns_after_reload) Optimization
1832 Reschedule instructions after register allocation
1834 ; This flag should be on when a target implements non-trivial
1835 ; scheduling hooks, maybe saving some information for its own sake.
1836 ; On IA64, for example, this is used for correct bundling.
1837 fselective-scheduling
1838 Common Report Var(flag_selective_scheduling) Optimization
1839 Schedule instructions using selective scheduling algorithm
1841 fselective-scheduling2
1842 Common Report Var(flag_selective_scheduling2) Optimization
1843 Run selective scheduling after reload
1845 fsel-sched-pipelining
1846 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1847 Perform software pipelining of inner loops during selective scheduling
1849 fsel-sched-pipelining-outer-loops
1850 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1851 Perform software pipelining of outer loops during selective scheduling
1853 fsel-sched-reschedule-pipelined
1854 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1855 Reschedule pipelined regions without pipelining
1857 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1858 ; of stalled insns into the ready list.
1859 fsched-stalled-insns
1860 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1861 Allow premature scheduling of queued insns
1863 fsched-stalled-insns=
1864 Common RejectNegative Joined UInteger
1865 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1867 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1868 ; be examined for a dependency on a stalled insn that is candidate for
1869 ; premature removal from the queue of stalled insns into the ready list (has
1870 ; an effect only if the flag 'sched_stalled_insns' is set).
1871 fsched-stalled-insns-dep
1872 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1873 Set dependence distance checking in premature scheduling of queued insns
1875 fsched-stalled-insns-dep=
1876 Common RejectNegative Joined UInteger
1877 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1879 fsched-group-heuristic
1880 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1881 Enable the group heuristic in the scheduler
1883 fsched-critical-path-heuristic
1884 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1885 Enable the critical path heuristic in the scheduler
1887 fsched-spec-insn-heuristic
1888 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1889 Enable the speculative instruction heuristic in the scheduler
1891 fsched-rank-heuristic
1892 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1893 Enable the rank heuristic in the scheduler
1895 fsched-last-insn-heuristic
1896 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1897 Enable the last instruction heuristic in the scheduler
1899 fsched-dep-count-heuristic
1900 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1901 Enable the dependent count heuristic in the scheduler
1904 Common Report Var(flag_section_anchors) Optimization
1905 Access data in the same section from shared anchor points
1909 Does nothing. Preserved for backward compatibility.
1913 Does nothing. Preserved for backward compatibility.
1916 Common Report Var(flag_ree) Init(0)
1917 Turn on Redundant Extensions Elimination pass.
1920 Common Report Var(flag_show_column) Init(1)
1921 Show column numbers in diagnostics, when available. Default on
1924 Common Report Var(flag_shrink_wrap) Optimization
1925 Emit function prologues only before parts of the function that need it,
1926 rather than at the top of the function.
1929 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1930 Disable optimizations observable by IEEE signaling NaNs
1933 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1934 Disable floating point optimizations that ignore the IEEE signedness of zero
1936 fsingle-precision-constant
1937 Common Report Var(flag_single_precision_constant) Optimization
1938 Convert floating point constants to single precision constants
1940 fsplit-ivs-in-unroller
1941 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1942 Split lifetimes of induction variables when loops are unrolled
1945 Common Report Var(flag_split_stack) Init(-1)
1946 Generate discontiguous stack frames
1949 Common Report Var(flag_split_wide_types) Optimization
1950 Split wide types into independent registers
1952 fvariable-expansion-in-unroller
1953 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1954 Apply variable expansion when loops are unrolled
1957 Common Report RejectNegative Joined
1958 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1961 Common Alias(fstack-check=, specific, no)
1962 Insert stack checking code into the program. Same as -fstack-check=specific
1965 Common Var(common_deferred_options) Defer
1967 fstack-limit-register=
1968 Common RejectNegative Joined Var(common_deferred_options) Defer
1969 -fstack-limit-register=<register> Trap if the stack goes past <register>
1971 fstack-limit-symbol=
1972 Common RejectNegative Joined Var(common_deferred_options) Defer
1973 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1976 Common Report Var(flag_stack_protect, 1)
1977 Use propolice as a stack protection method
1979 fstack-protector-all
1980 Common Report RejectNegative Var(flag_stack_protect, 2)
1981 Use a stack protection method for every function
1983 fstack-protector-strong
1984 Common Report RejectNegative Var(flag_stack_protect, 3)
1985 Use a smart stack protection method for certain functions
1988 Common RejectNegative Var(flag_stack_usage)
1989 Output stack usage information on a per-function basis
1993 Does nothing. Preserved for backward compatibility.
1995 ; Nonzero if we should do (language-dependent) alias analysis.
1996 ; Typically, this analysis will assume that expressions of certain
1997 ; types do not alias expressions of certain other types. Only used
1998 ; if alias analysis (in general) is enabled.
2000 Common Report Var(flag_strict_aliasing) Optimization
2001 Assume strict aliasing rules apply
2004 Common Report Var(flag_strict_overflow)
2005 Treat signed overflow as undefined
2008 Common Report Var(flag_sync_libcalls) Init(1)
2009 Implement __atomic operations via libcalls to legacy __sync functions
2012 Common Report Var(flag_syntax_only)
2013 Check for syntax errors, then stop
2016 Common Report Var(flag_test_coverage)
2017 Create data files needed by \"gcov\"
2020 Common Report Var(flag_thread_jumps) Optimization
2021 Perform jump threading optimizations
2024 Common Report Var(time_report)
2025 Report the time taken by each compiler pass
2028 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2029 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
2032 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2035 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2038 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2041 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2044 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2047 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
2048 Reorder top level functions, variables, and asms
2051 Common Report Var(flag_tracer)
2052 Perform superblock formation via tail duplication
2054 ; Zero means that floating-point math operations cannot generate a
2055 ; (user-visible) trap. This is the case, for example, in nonstop
2056 ; IEEE 754 arithmetic.
2058 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2059 Assume floating-point operations can trap
2062 Common Report Var(flag_trapv) Optimization
2063 Trap for signed overflow in addition, subtraction and multiplication
2066 Common Report Var(flag_tree_ccp) Optimization
2067 Enable SSA-CCP optimization on trees
2070 Common Report Var(flag_tree_bit_ccp) Optimization
2071 Enable SSA-BIT-CCP optimization on trees
2075 Does nothing. Preserved for backward compatibility.
2078 Common Report Var(flag_tree_ch) Optimization
2079 Enable loop header copying on trees
2081 ftree-coalesce-inlined-vars
2082 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
2083 Enable coalescing of copy-related user variables that are inlined
2086 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
2087 Enable coalescing of all copy-related user variables
2090 Common Report Var(flag_tree_copyrename) Optimization
2091 Replace SSA temporaries with better names in copies
2094 Common Report Var(flag_tree_copy_prop) Optimization
2095 Enable copy propagation on trees
2097 ftree-store-copy-prop
2099 Does nothing. Preserved for backward compatibility.
2102 Common Report Var(flag_tree_cselim) Init(2) Optimization
2103 Transform condition stores into unconditional ones
2105 ftree-switch-conversion
2106 Common Report Var(flag_tree_switch_conversion) Optimization
2107 Perform conversions of switch initializations.
2110 Common Report Var(flag_tree_dce) Optimization
2111 Enable SSA dead code elimination optimization on trees
2113 ftree-dominator-opts
2114 Common Report Var(flag_tree_dom) Optimization
2115 Enable dominator optimizations
2118 Common Report Var(flag_tree_tail_merge) Optimization
2119 Enable tail merging on trees
2122 Common Report Var(flag_tree_dse) Optimization
2123 Enable dead store elimination
2126 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2127 Enable forward propagation on trees
2130 Common Report Var(flag_tree_fre) Optimization
2131 Enable Full Redundancy Elimination (FRE) on trees
2134 Common Report Var(flag_optimize_strlen) Optimization
2135 Enable string length optimizations on trees
2137 fisolate-erroneous-paths-dereference
2138 Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization
2139 Detect paths which trigger erroneous or undefined behaviour due to
2140 dereferencing a NULL pointer. Isolate those paths from the main control
2141 flow and turn the statement with erroneous or undefined behaviour into a trap.
2143 fisolate-erroneous-paths-attribute
2144 Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization
2145 Detect paths which trigger erroneous or undefined behaviour due a NULL value
2146 being used in a way which is forbidden by a returns_nonnull or nonnull
2147 attribute. Isolate those paths from the main control flow and turn the
2148 statement with erroneous or undefined behaviour into a trap.
2150 ftree-loop-distribution
2151 Common Report Var(flag_tree_loop_distribution) Optimization
2152 Enable loop distribution on trees
2154 ftree-loop-distribute-patterns
2155 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2156 Enable loop distribution for patterns transformed into a library call
2159 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2160 Enable loop invariant motion on trees
2163 Common Alias(floop-interchange)
2164 Enable loop interchange transforms. Same as -floop-interchange
2167 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2168 Create canonical induction variables in loops
2171 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2172 Enable loop optimizations on tree level
2174 ftree-parallelize-loops=
2175 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2176 Enable automatic parallelization of loops
2179 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2180 Enable hoisting loads from conditional pointers.
2183 Common Report Var(flag_tree_pre) Optimization
2184 Enable SSA-PRE optimization on trees
2187 Common Report Var(flag_tree_partial_pre) Optimization
2188 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2191 Common Report Var(flag_tree_pta) Optimization
2192 Perform function-local points-to analysis on trees.
2195 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2196 Enable reassociation on tree level
2200 Does nothing. Preserved for backward compatibility.
2203 Common Report Var(flag_tree_sink) Optimization
2204 Enable SSA code sinking on trees
2207 Common Report Var(flag_tree_slsr) Optimization
2208 Perform straight-line strength reduction
2211 Common Report Var(flag_tree_sra) Optimization
2212 Perform scalar replacement of aggregates
2215 Common Report Var(flag_tree_ter) Optimization
2216 Replace temporary expressions in the SSA->normal pass
2219 Common Report Var(flag_tree_live_range_split) Optimization
2220 Perform live range splitting during the SSA->normal pass
2223 Common Report Var(flag_tree_vrp) Init(0) Optimization
2224 Perform Value Range Propagation on trees
2227 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2228 Compile whole compilation unit at a time
2231 Common Report Var(flag_unroll_loops) Optimization
2232 Perform loop unrolling when iteration count is known
2235 Common Report Var(flag_unroll_all_loops) Optimization
2236 Perform loop unrolling for all loops
2238 ; Nonzero means that loop optimizer may assume that the induction variables
2239 ; that control loops do not overflow and that the loops with nontrivial
2240 ; exit condition are not infinite
2241 funsafe-loop-optimizations
2242 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2243 Allow loop optimizations to assume that the loops behave in normal way
2246 Common Report Var(flag_associative_math) SetByCombined
2247 Allow optimization for floating-point arithmetic which may change the
2248 result of the operation due to rounding.
2251 Common Report Var(flag_reciprocal_math) SetByCombined
2252 Same as -fassociative-math for expressions which include division.
2254 ; Nonzero means that unsafe floating-point math optimizations are allowed
2255 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2256 ; are allowed to assume that their arguments and results are "normal"
2257 ; (e.g., nonnegative for SQRT).
2258 funsafe-math-optimizations
2259 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2260 Allow math optimizations that may violate IEEE or ISO standards
2263 Common Report Var(flag_unswitch_loops) Optimization
2264 Perform loop unswitching
2267 Common Report Var(flag_unwind_tables) Optimization
2268 Just generate unwind tables for exception handling
2271 Common Driver Negative(fuse-ld=gold)
2272 Use the bfd linker instead of the default linker
2275 Common Driver Negative(fuse-ld=bfd)
2276 Use the gold linker instead of the default linker
2279 Common Undocumented Var(flag_use_linker_plugin)
2281 ; Positive if we should track variables, negative if we should run
2282 ; the var-tracking pass only to discard debug annotations, zero if
2283 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2284 ; will be set according to optimize, debug_info_level and debug_hooks
2285 ; in process_options ().
2287 Common Report Var(flag_var_tracking) Init(2) Optimization
2288 Perform variable tracking
2290 ; Positive if we should track variables at assignments, negative if
2291 ; we should run the var-tracking pass only to discard debug
2292 ; annotations. When flag_var_tracking_assignments ==
2293 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2294 fvar-tracking-assignments
2295 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2296 Perform variable tracking by annotating assignments
2298 ; Nonzero if we should toggle flag_var_tracking_assignments after
2299 ; processing options and computing its default. */
2300 fvar-tracking-assignments-toggle
2301 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2302 Toggle -fvar-tracking-assignments
2304 ; Positive if we should track uninitialized variables, negative if
2305 ; we should run the var-tracking pass only to discard debug
2306 ; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
2307 ; will be set according to flag_var_tracking.
2308 fvar-tracking-uninit
2309 Common Report Var(flag_var_tracking_uninit) Optimization
2310 Perform variable tracking and also tag variables that are uninitialized
2313 Common Report Var(flag_tree_vectorize) Optimization
2314 Enable vectorization on trees
2316 ftree-vectorizer-verbose=
2317 Common Joined RejectNegative Ignore
2318 Does nothing. Preserved for backward compatibility.
2320 ftree-loop-vectorize
2321 Common Report Var(flag_tree_loop_vectorize) Optimization
2322 Enable loop vectorization on trees
2325 Common Report Var(flag_tree_slp_vectorize) Optimization
2326 Enable basic block vectorization (SLP) on trees
2329 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT)
2330 Specifies the cost model for vectorization
2333 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED)
2334 Specifies the vectorization cost model for code marked with a simd directive
2337 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2340 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2343 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2346 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2349 Common RejectNegative Alias(fvect-cost-model=,dynamic)
2350 Enables the dynamic vectorizer cost model. Preserved for backward compatibility.
2353 Common RejectNegative Alias(fvect-cost-model=,unlimited)
2354 Enables the unlimited vectorizer cost model. Preserved for backward compatibility.
2356 ftree-vect-loop-version
2358 Does nothing. Preserved for backward compatibility.
2361 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2362 Enable copy propagation of scalar-evolution information.
2364 ; -fverbose-asm causes extra commentary information to be produced in
2365 ; the generated assembly code (to make it more readable). This option
2366 ; is generally only of use to those who actually need to read the
2367 ; generated assembly code (perhaps while debugging the compiler itself).
2368 ; -fno-verbose-asm, the default, causes the extra information
2369 ; to not be added and is useful when comparing two assembler files.
2371 Common Report Var(flag_verbose_asm)
2372 Add extra commentary to assembler output
2375 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2376 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2379 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2382 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2385 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2388 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2391 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2394 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2395 Validate vtable pointers before using them.
2398 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2401 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2404 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2407 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2410 Common Var(flag_vtv_counts)
2411 Output vtable verification counters.
2414 Common Var(flag_vtv_debug)
2415 Output vtable verification pointer sets information.
2418 Common Report Var(flag_value_profile_transformations) Optimization
2419 Use expression value profiles in optimizations
2422 Common Report Var(flag_web) Init(2) Optimization
2423 Construct webs and split unrelated uses of single variable
2425 ftree-builtin-call-dce
2426 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2427 Enable conditional dead code elimination for builtin calls
2430 Common Report Var(flag_whole_program) Init(0) Optimization
2431 Perform whole program optimizations
2434 Common Report Var(flag_wrapv) Optimization
2435 Assume signed arithmetic overflow wraps around
2437 fzero-initialized-in-bss
2438 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2439 Put zero initialized data in the bss section
2442 Common JoinedOrMissing
2443 Generate debug information in default format
2446 Common JoinedOrMissing Negative(gdwarf)
2447 Generate debug information in COFF format
2450 Common JoinedOrMissing Negative(gdwarf-)
2451 Generate debug information in default version of DWARF format
2454 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2455 Generate debug information in DWARF v2 (or later) format
2458 Common JoinedOrMissing
2459 Generate debug information in default extended format
2462 Common Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
2463 Don't generate DWARF pubnames and pubtypes sections.
2466 Common Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
2467 Generate DWARF pubnames and pubtypes sections.
2470 Common Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
2471 Generate DWARF pubnames and pubtypes sections with GNU extensions.
2473 gno-record-gcc-switches
2474 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2475 Don't record gcc command line switches in DWARF DW_AT_producer.
2477 grecord-gcc-switches
2478 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2479 Record gcc command line switches in DWARF DW_AT_producer.
2482 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2483 Don't generate debug information in separate .dwo files
2486 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2487 Generate debug information in separate .dwo files
2490 Common JoinedOrMissing Negative(gstabs+)
2491 Generate debug information in STABS format
2494 Common JoinedOrMissing Negative(gvms)
2495 Generate debug information in extended STABS format
2498 Common RejectNegative Var(dwarf_strict,0) Init(0)
2499 Emit DWARF additions beyond selected version
2502 Common Report RejectNegative Var(dwarf_strict,1)
2503 Don't emit DWARF additions beyond selected version
2506 Common Report Var(flag_gtoggle)
2507 Toggle debug information generation
2510 Common JoinedOrMissing Negative(gxcoff)
2511 Generate debug information in VMS format
2514 Common JoinedOrMissing Negative(gxcoff+)
2515 Generate debug information in XCOFF format
2518 Common JoinedOrMissing Negative(gcoff)
2519 Generate debug information in extended XCOFF format
2522 Driver Joined Separate
2525 Common Joined Var(plugindir_string) Init(0)
2526 -iplugindir=<dir> Set <dir> to be the default plugin directory
2529 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2530 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory
2533 Driver Joined Separate
2538 no-canonical-prefixes
2551 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2552 -o <file> Place output into <file>
2555 Common Var(profile_flag)
2556 Enable function profiling
2559 Driver Var(pass_exit_codes)
2562 Common Alias(Wpedantic)
2565 Common Var(flag_pedantic_errors)
2566 Like -pedantic but issue them as errors
2572 Driver Var(use_pipes)
2575 Driver JoinedOrMissing Var(print_file_name)
2577 print-libgcc-file-name
2580 print-multi-directory
2581 Driver Var(print_multi_directory)
2584 Driver Var(print_multi_lib)
2586 print-multi-os-directory
2587 Driver Var(print_multi_os_directory)
2590 Driver Var(print_multiarch)
2593 Driver JoinedOrMissing Var(print_prog_name)
2596 Driver Var(print_search_dirs)
2599 Driver Var(print_sysroot)
2601 print-sysroot-headers-suffix
2602 Driver Var(print_sysroot_headers_suffix)
2605 Common Var(quiet_flag) RejectDriver
2606 Do not display functions compiled or elapsed time
2624 Driver Var(report_times)
2627 Driver JoinedOrMissing
2630 Driver Joined Separate
2634 ; C option, but driver must not handle as "-u ndef".
2637 Common Driver Var(verbose_flag)
2638 Enable verbose output
2641 Common Var(version_flag) RejectDriver
2642 Display the compiler's version
2645 Common Var(inhibit_warnings)
2649 Driver Separate Var(wrapper_string)
2652 Driver Joined Separate
2655 Driver RejectNegative Negative(pie)
2656 Create a shared library
2662 Driver Separate Alias(specs=)
2675 ; Documented for Fortran, but always accepted by driver.
2682 ; Documented for Go, but always accepted by driver.
2700 Driver RejectNegative Negative(shared)
2701 Create a position independent executable
2704 Driver Joined Separate
2706 ; This comment is to ensure we retain the blank line above.