1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003-2016 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 ; This variable is set to non-0 only by LTO front-end. 1 indicates that
50 ; the output produced will be used for incrmeental linking (thus weak symbols
51 ; can still be bound).
53 int flag_incremental_link = 0
55 ; 0 means straightforward implementation of complex divide acceptable.
56 ; 1 means wide ranges of inputs must work for complex divide.
57 ; 2 means C99-like requirements for complex multiply and divide.
59 int flag_complex_method = 1
61 ; Nonzero if subexpressions must be evaluated from left-to-right.
63 int flag_evaluation_order = 0
65 ; Language specific warning pass for unused results.
67 bool flag_warn_unused_result = false
72 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
76 ; Nonzero if we should write GIMPLE bytecode for offload compilation.
78 int flag_generate_offload = 0
80 ; True to warn about any objects definitions whose size is larger
81 ; than N bytes. Also want about function definitions whose returned
82 ; values are larger than N bytes, where N is 'larger_than_size'.
87 HOST_WIDE_INT larger_than_size
89 ; True to warn about any function whose frame size is larger
92 bool warn_frame_larger_than
95 HOST_WIDE_INT frame_larger_than_size
97 ; Nonzero means we should be saving declaration info into a .X file.
99 int flag_gen_aux_info = 0
101 ; Nonzero if we are compiling code for a shared library, zero for
106 ; These two are really VEC(char_p,heap) *.
109 void *flag_instrument_functions_exclude_functions
112 void *flag_instrument_functions_exclude_files
114 ; Generic structs (e.g. templates not explicitly specialized)
115 ; may not have a compilation unit associated with them, and so
116 ; may need to be treated differently from ordinary structs.
118 ; Structs only handled by reference (indirectly), will also usually
119 ; not need as much debugging information.
122 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
125 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
127 ; True if we should exit after parsing options.
129 bool exit_after_options
131 ; Type(s) of debugging information we are producing (if any). See
132 ; flag-types.h for the definitions of the different possible types of
133 ; debugging information.
135 enum debug_info_type write_symbols = NO_DEBUG
137 ; Level of debugging information we are producing. See flag-types.h
138 ; for the definitions of the different possible levels.
140 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
142 ; Nonzero means use GNU-only extensions in the generated symbolic
143 ; debugging information. Currently, this only has an effect when
144 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
146 bool use_gnu_debug_info_extensions
148 ; Original value of maximum field alignment in bytes, specified via
149 ; -fpack-struct=<value>.
151 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
153 ; Type of stack check.
155 enum stack_check_type flag_stack_check = NO_STACK_CHECK
157 ; True if stack usage information needs to be computed.
159 bool flag_stack_usage_info = false
161 ; -dA causes debug commentary information to be produced in
162 ; the generated assembly code (to make it more readable). This option
163 ; is generally only of use to those who actually need to read the
164 ; generated assembly code (perhaps while debugging the compiler itself).
165 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
166 ; to be a catchall for printing debug information in the assembler file.
171 ; Balance between GNAT encodings and standard DWARF to emit.
173 enum dwarf_gnat_encodings gnat_encodings = DWARF_GNAT_ENCODINGS_DEFAULT
175 ; -dP causes the rtl to be emitted as a comment in assembly.
177 int flag_dump_rtl_in_asm
179 ; Whether -da was passed (used only in handle_common_deferred_options).
181 bool flag_dump_all_passed
183 ; Other flags saying which kinds of debugging dump have been requested.
186 int rtl_dump_and_exit
189 int flag_print_asm_name
191 ; Name of top-level original source file (what was input to cpp).
192 ; This comes from the #-command at the beginning of the actual input.
193 ; If there isn't any there, then this is the cc1 input file name.
195 const char *main_input_filename
197 ; Pointer to base name in main_input_filename, with directories and a
198 ; single final extension removed, and the length of this base
202 const char *main_input_basename
205 int main_input_baselength
207 ; Which options have been printed by --help.
211 ; Which enums have been printed by --help. 0 = not printed, no
212 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
215 char *help_enum_printed
217 ; The number of columns for --help output.
219 unsigned int help_columns
221 ; Whether this options structure has been through finish_options
223 bool flag_opts_finished
225 ; What the sanitizer should instrument
227 unsigned int flag_sanitize
229 ; What sanitizers should recover from errors
231 unsigned int flag_sanitize_recover = (SANITIZE_UNDEFINED | SANITIZE_NONDEFAULT | SANITIZE_KERNEL_ADDRESS) & ~(SANITIZE_UNREACHABLE | SANITIZE_RETURN)
233 fsanitize-coverage=trace-pc
234 Common Report Var(flag_sanitize_coverage)
235 Enable coverage-guided fuzzing code instrumentation.
236 Inserts call to __sanitizer_cov_trace_pc into every basic block.
238 ; Flag whether a prefix has been added to dump_base_name
240 bool dump_base_name_prefixed = false
242 ; Flag whether HSA generation has been explicitely disabled
244 bool flag_disable_hsa = false
256 Driver Alias(coverage)
262 Common Separate Alias(d)
265 Common Joined Alias(d)
268 Common Separate Alias(dumpbase)
271 Common Separate Alias(dumpdir)
274 Driver Separate Alias(e)
277 Driver Joined Alias(e)
280 Common Warning Alias(Wextra)
283 Driver Separate Alias(Xassembler)
286 Driver JoinedOrMissing Alias(Xassembler)
289 Driver Separate Alias(Xlinker)
292 Driver JoinedOrMissing Alias(Xlinker)
295 Driver Separate Alias(u)
298 Driver Joined Alias(u)
301 Common Driver Var(help_flag)
302 Display this information.
305 Common Driver Report Joined
306 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params.
309 Driver Separate Alias(x)
312 Driver Joined Alias(x)
315 Driver Separate Alias(L)
318 Driver Joined Alias(L)
320 -no-canonical-prefixes
321 Driver Alias(no-canonical-prefixes)
323 -no-standard-libraries
324 Driver Alias(nostdlib)
327 Driver Var(no_sysroot_suffix)
336 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
339 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
342 Driver Alias(pass-exit-codes)
345 Common Alias(Wpedantic)
348 Common Alias(pedantic-errors)
357 Driver Separate Alias(B)
360 Driver JoinedOrMissing Alias(B)
366 Driver Separate Alias(print-file-name=)
369 Driver JoinedOrMissing Alias(print-file-name=)
371 -print-libgcc-file-name
372 Driver Alias(print-libgcc-file-name)
374 -print-multi-directory
375 Driver Alias(print-multi-directory)
378 Driver Alias(print-multi-lib)
380 -print-multi-os-directory
381 Driver Alias(print-multi-os-directory)
384 Driver Alias(print-multiarch)
387 Driver Separate Alias(print-prog-name=)
390 Driver JoinedOrMissing Alias(print-prog-name=)
393 Driver Alias(print-search-dirs)
396 Driver Alias(print-sysroot)
398 -print-sysroot-headers-suffix
399 Driver Alias(print-sysroot-headers-suffix)
405 Driver Alias(save-temps)
411 Driver Separate Alias(specs=)
414 Driver Joined Alias(specs=)
420 Driver Alias(symbolic)
424 Alias for --help=target.
432 ;; The driver used to convert options such as --help into forms such
433 ;; as -fhelp; the following four entries are for compatibility with
434 ;; any direct uses of those (undocumented) -f forms
436 Common Driver Alias(-help)
439 Common Driver Joined Alias(-help=)
442 Common Driver Alias(-target-help)
445 Common Driver Alias(-version)
449 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters.
452 Common Joined Alias(-param)
455 Driver Separate Alias(-sysroot=)
458 Driver JoinedOrMissing
464 Driver Joined Separate
470 Driver Joined Separate
476 Common JoinedOrMissing Optimization
477 -O<number> Set optimization level to <number>.
481 Optimize for space rather than speed.
485 Optimize for speed disregarding exact standards compliance.
489 Optimize for debugging experience rather than speed or size.
501 Driver Joined Separate
507 Driver Joined Separate
528 Common RejectNegative Warning Alias(Wextra)
529 This switch is deprecated; use -Wextra instead.
532 Driver JoinedOrMissing
535 Driver JoinedOrMissing
538 Driver JoinedOrMissing
541 Common Var(warn_aggregate_return) Warning
542 Warn about returning structures, unions or arrays.
544 Waggressive-loop-optimizations
545 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
546 Warn if a loop with constant number of iterations triggers undefined behavior.
549 Common Var(warn_array_bounds) Warning
550 Warn if an array is accessed out of bounds.
553 Common Joined RejectNegative UInteger Var(warn_array_bounds) Warning
554 Warn if an array is accessed out of bounds.
557 Common Var(warn_attributes) Init(1) Warning
558 Warn about inappropriate attribute usage.
561 Common Var(warn_cast_align) Warning
562 Warn about pointer casts which increase alignment.
565 Common Var(warn_cpp) Init(1) Warning
566 Warn when a #warning directive is encountered.
568 Wdeprecated-declarations
569 Common Var(warn_deprecated_decl) Init(1) Warning
570 Warn about uses of __attribute__((deprecated)) declarations.
572 Wdisabled-optimization
573 Common Var(warn_disabled_optimization) Warning
574 Warn when an optimization pass is disabled.
577 Common Var(warnings_are_errors)
578 Treat all warnings as errors.
582 Treat specified warning as error.
585 Common Var(extra_warnings) Warning
586 Print extra (possibly unwanted) warnings.
589 Common Var(flag_fatal_errors)
590 Exit on the first error occurred.
593 Common RejectNegative Joined UInteger Warning
594 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes.
597 Common Var(warn_free_nonheap_object) Init(1) Warning
598 Warn when attempting to free a non-heap object.
601 Common Var(warn_hsa) Init(1) Warning
602 Warn when a function cannot be expanded to HSAIL.
604 Wimplicit-fallthrough
605 Common Alias(Wimplicit-fallthrough=,3,0) Warning
607 Wimplicit-fallthrough=
608 Common Var(warn_implicit_fallthrough) RejectNegative Joined UInteger Warning
609 Warn when a switch case falls through.
612 Common Var(warn_inline) Warning
613 Warn when an inlined function cannot be inlined.
615 Winvalid-memory-model
616 Common Var(warn_invalid_memory_model) Init(1) Warning
617 Warn when an atomic memory model parameter is known to be outside the valid range.
620 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
623 Common RejectNegative Joined UInteger Warning
624 -Wlarger-than=<number> Warn if an object is larger than <number> bytes.
627 Var(warn_nonnull_compare) Warning
628 Warn if comparing pointer parameter with nonnull attribute with NULL.
631 Common Var(warn_null_dereference) Warning
632 Warn if dereferencing a NULL pointer may lead to erroneous or undefined behavior.
634 Wunsafe-loop-optimizations
635 Common Var(warn_unsafe_loop_optimizations) Warning
636 Warn if the loop cannot be optimized due to nontrivial assumptions.
639 Common Warning Alias(Wsuggest-attribute=noreturn)
642 Common Var(warn_odr_violations) Init(1) Warning
643 Warn about some C++ One Definition Rule violations during link time optimization.
646 Common Var(warn_overflow) Init(1) Warning
647 Warn about overflow in arithmetic expressions.
650 Common Var(warn_lto_type_mismatch) Init(1) Warning
651 During link time optimization warn about mismatched types of global declarations.
654 Common Var(warn_packed) Warning
655 Warn when the packed attribute has no effect on struct layout.
658 Common Var(warn_padded) Warning
659 Warn when padding is required to align structure members.
662 Common Var(pedantic) Init(0) Warning
663 Issue warnings needed for strict compliance to the standard.
666 Common Var(warn_return_local_addr) Init(1) Warning
667 Warn about returning a pointer/reference to a local or temporary variable.
670 Common Var(warn_shadow) Warning
671 Warn when one local variable shadows another.
674 Common Var(warn_stack_protect) Warning
675 Warn when not issuing stack smashing protection for some reason.
678 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
679 Warn if stack usage might be larger than specified amount.
683 Warn about code which might break strict aliasing rules.
686 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
687 Warn about code which might break strict aliasing rules.
691 Warn about optimizations that assume that signed overflow is undefined.
694 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
695 Warn about optimizations that assume that signed overflow is undefined.
697 Wsuggest-attribute=const
698 Common Var(warn_suggest_attribute_const) Warning
699 Warn about functions which might be candidates for __attribute__((const)).
701 Wsuggest-attribute=pure
702 Common Var(warn_suggest_attribute_pure) Warning
703 Warn about functions which might be candidates for __attribute__((pure)).
705 Wsuggest-attribute=noreturn
706 Common Var(warn_suggest_attribute_noreturn) Warning
707 Warn about functions which might be candidates for __attribute__((noreturn)).
710 Common Var(warn_suggest_final_types) Warning
711 Warn about C++ polymorphic types where adding final keyword would improve code quality.
713 Wsuggest-final-methods
714 Common Var(warn_suggest_final_methods) Warning
715 Warn about C++ virtual methods where adding final keyword would improve code quality.
718 Common Var(warn_switch_unreachable) Warning Init(1)
719 Warn about statements between switch's controlling expression and the first
723 Common Var(warn_system_headers) Warning
724 Do not suppress warnings from system headers.
727 Common Var(warn_trampolines) Warning
728 Warn whenever a trampoline is generated.
731 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
732 Warn if a comparison is always true or always false due to the limited range of the data type.
735 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
736 Warn about uninitialized automatic variables.
739 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
740 Warn about maybe uninitialized automatic variables.
743 Common Ignore Warning
744 Does nothing. Preserved for backward compatibility.
747 Common Var(warn_unused) Init(0) Warning
748 Enable all -Wunused- warnings.
750 Wunused-but-set-parameter
751 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
752 Warn when a function parameter is only set, otherwise unused.
754 Wunused-but-set-variable
755 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
756 Warn when a variable is only set, otherwise unused.
759 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
760 Warn when a function is unused.
763 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
764 Warn when a label is unused.
767 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
768 Warn when a function parameter is unused.
771 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
772 Warn when an expression value is unused.
775 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
776 Warn when a variable is unused.
779 Common Var(warn_coverage_mismatch) Init(1) Warning
780 Warn in case profiles in -fprofile-use do not match.
782 Wvector-operation-performance
783 Common Var(warn_vector_operation_performance) Warning
784 Warn when a vector operation is compiled outside the SIMD.
799 Common Separate Var(aux_info_file_name)
800 -aux-info <file> Emit declaration information into <file>.
803 Common Joined Alias(aux-info)
806 Common Separate RejectDriver Var(aux_base_name)
809 Common Separate RejectDriver
819 -d<letters> Enable dumps from specific passes of the compiler.
822 Common Separate Var(dump_base_name)
823 -dumpbase <file> Set the file basename to be used for dumps.
826 Common Separate Var(dump_dir_name)
827 -dumpdir <dir> Set the directory name to be used for dumps.
839 Driver Joined Separate
841 ; This option has historically been passed down to the linker by an
842 ; accident of a %{e*} spec, so ensure it continues to be passed down
843 ; as a single option. The supported option for this purpose is
844 ; -rdynamic. See PR 47390.
848 ; The version of the C++ ABI in use. The following values are allowed:
850 ; 0: The version of the ABI believed most conformant with the C++ ABI
851 ; specification. This ABI may change as bugs are discovered and fixed.
852 ; Therefore, 0 will not necessarily indicate the same ABI in different
855 ; 1: The version of the ABI first used in G++ 3.2. No longer selectable.
857 ; 2: The version of the ABI first used in G++ 3.4, and the default
860 ; 3: The version of the ABI that fixes the missing underscore
861 ; in template non-type arguments of pointer type.
863 ; 4: The version of the ABI that introduces unambiguous mangling of
864 ; vector types. First selectable in G++ 4.5.
866 ; 5: The version of the ABI that ignores attribute const/noreturn
867 ; in function pointer mangling, and corrects mangling of decltype and
868 ; function parameters used in other parameters and the return type.
869 ; First selectable in G++ 4.6.
871 ; 6: The version of the ABI that doesn't promote scoped enums to int and
872 ; changes the mangling of template argument packs, const/static_cast,
873 ; prefix ++ and --, and a class scope function used as a template
875 ; First selectable in G++ 4.7.
877 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
878 ; corrects the mangling of lambdas in default argument scope.
879 ; First selectable in G++ 4.8.
881 ; 8: The version of the ABI that corrects the substitution behavior of
882 ; function types with function-cv-qualifiers.
883 ; First selectable in G++ 4.9 and default in G++ 5.
885 ; 9: The version of the ABI that corrects the alignment of nullptr_t.
886 ; First selectable and default in G++ 5.2.
888 ; 10: The version of the ABI that mangles attributes that affect type
889 ; identity, such as ia32 calling convention attributes (stdcall, etc.)
890 ; Default in G++ 6 (set in c_common_post_options).
892 ; 11: The version of the ABI that corrects mangling of sizeof... expressions.
895 ; Additional positive integers will be assigned as new versions of
896 ; the ABI become the default version of the ABI.
898 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0)
899 The version of the C++ ABI in use.
901 faggressive-loop-optimizations
902 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
903 Aggressively optimize loops using language constraints.
906 Common Report Var(align_functions,0) Optimization UInteger
907 Align the start of functions.
910 Common RejectNegative Joined UInteger Var(align_functions)
913 Common Report Var(align_jumps,0) Optimization UInteger
914 Align labels which are only reached by jumping.
917 Common RejectNegative Joined UInteger Var(align_jumps)
920 Common Report Var(align_labels,0) Optimization UInteger
924 Common RejectNegative Joined UInteger Var(align_labels)
927 Common Report Var(align_loops,0) Optimization UInteger
928 Align the start of loops.
931 Common RejectNegative Joined UInteger Var(align_loops)
935 Does nothing. Preserved for backward compatibility.
939 Does nothing. Preserved for backward compatibility.
941 fargument-noalias-global
943 Does nothing. Preserved for backward compatibility.
945 fargument-noalias-anything
947 Does nothing. Preserved for backward compatibility.
950 Common Driver Report Joined
951 Select what to sanitize.
954 Common Joined RejectNegative Var(common_deferred_options) Defer
955 -fasan-shadow-offset=<number> Use custom shadow memory offset.
958 Common Joined RejectNegative Var(common_deferred_options) Defer
959 -fsanitize-sections=<sec1,sec2,...> Sanitize global variables
960 in user-defined sections.
964 After diagnosing undefined behavior attempt to continue execution.
968 This switch is deprecated; use -fsanitize-recover= instead.
970 fsanitize-undefined-trap-on-error
971 Common Driver Report Var(flag_sanitize_undefined_trap_on_error) Init(0)
972 Use trap instead of a library function for undefined behavior sanitization.
974 fasynchronous-unwind-tables
975 Common Report Var(flag_asynchronous_unwind_tables) Optimization
976 Generate unwind tables that are exact at each instruction boundary.
979 Common Report Var(flag_auto_inc_dec) Init(1) Optimization
980 Generate auto-inc/dec instructions.
983 Common Report Var(flag_auto_profile)
984 Use sample profile information for call graph node weights. The default
985 profile file is fbdata.afdo in 'pwd'.
988 Common Joined RejectNegative Var(auto_profile_file)
989 Use sample profile information for call graph node weights. The profile
990 file is specified in the argument.
992 ; -fcheck-bounds causes gcc to generate array bounds checks.
993 ; For C, C++ and ObjC: defaults off.
994 ; For Java: defaults to on.
995 ; For Fortran: defaults to off.
997 Common Report Var(flag_bounds_check)
998 Generate code to check bounds before indexing arrays.
1001 Common Report Var(flag_branch_on_count_reg) Optimization
1002 Replace add, compare, branch with branch on count register.
1004 fbranch-probabilities
1005 Common Report Var(flag_branch_probabilities) Optimization
1006 Use profiling information for branch probabilities.
1008 fbranch-target-load-optimize
1009 Common Report Var(flag_branch_target_load_optimize) Optimization
1010 Perform branch target load optimization before prologue / epilogue threading.
1012 fbranch-target-load-optimize2
1013 Common Report Var(flag_branch_target_load_optimize2) Optimization
1014 Perform branch target load optimization after prologue / epilogue threading.
1017 Common Report Var(flag_btr_bb_exclusive) Optimization
1018 Restrict target load migration not to re-use registers in any basic block.
1021 Common Joined RejectNegative Var(common_deferred_options) Defer
1022 -fcall-saved-<register> Mark <register> as being preserved across functions.
1025 Common Joined RejectNegative Var(common_deferred_options) Defer
1026 -fcall-used-<register> Mark <register> as being corrupted by function calls.
1028 ; Nonzero for -fcaller-saves: allocate values in regs that need to
1029 ; be saved across function calls, if that produces overall better code.
1030 ; Optional now, so people can test it.
1032 Common Report Var(flag_caller_saves) Optimization
1033 Save registers around function calls.
1036 Common Report Var(flag_check_data_deps)
1037 This switch is deprecated; do not use.
1040 Common Var(flag_check_new)
1041 Check the return value of new in C++.
1044 Common Var(flag_checking) Init(CHECKING_P ? ENABLE_EXTRA_CHECKING ? 2 : 1 : 0)
1045 Perform internal consistency checkings.
1048 Common Joined RejectNegative UInteger Var(flag_checking)
1049 Perform internal consistency checkings.
1052 Common Report Var(flag_code_hoisting) Optimization
1053 Enable code hoisting.
1055 fcombine-stack-adjustments
1056 Common Report Var(flag_combine_stack_adjustments) Optimization
1057 Looks for opportunities to reduce stack adjustments and stack references.
1060 Common Report Var(flag_no_common,0)
1061 Do not put uninitialized globals in the common section.
1065 ; Converted by the driver to -fcompare-debug= options.
1068 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
1069 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump.
1071 fcompare-debug-second
1072 Common Driver RejectNegative Var(flag_compare_debug)
1073 Run only the second compilation of -fcompare-debug.
1076 Common Report Var(flag_compare_elim_after_reload) Optimization
1077 Perform comparison elimination after register allocation has finished.
1080 Common Var(flag_conserve_stack) Optimization
1081 Do not perform optimizations increasing noticeably stack usage.
1084 Common Report Var(flag_cprop_registers) Optimization
1085 Perform a register copy-propagation optimization pass.
1088 Common Report Var(flag_crossjumping) Optimization
1089 Perform cross-jumping optimization.
1092 Common Report Var(flag_cse_follow_jumps) Optimization
1093 When running CSE, follow jumps to their targets.
1097 Does nothing. Preserved for backward compatibility.
1100 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
1101 Omit range reduction step when performing complex division.
1104 Common Report Var(flag_cx_fortran_rules) Optimization
1105 Complex multiplication and division follow Fortran rules.
1108 Common Report Var(flag_data_sections)
1109 Place data items into their own section.
1112 Common Report Var(common_deferred_options) Defer
1113 List all available debugging counters with their limits and counts.
1116 Common RejectNegative Joined Var(common_deferred_options) Defer
1117 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
1120 Common Joined RejectNegative Var(common_deferred_options) Defer
1121 Map one directory name to another in debug information.
1123 fdebug-types-section
1124 Common Report Var(flag_debug_types_section) Init(0)
1125 Output .debug_types section when using DWARF v4 debuginfo.
1127 ; Nonzero for -fdefer-pop: don't pop args after each function call
1128 ; instead save them up to pop many calls' args with one insns.
1130 Common Report Var(flag_defer_pop) Optimization
1131 Defer popping functions args from stack until later.
1134 Common Report Var(flag_delayed_branch) Optimization
1135 Attempt to fill delay slots of branch instructions.
1137 fdelete-dead-exceptions
1138 Common Report Var(flag_delete_dead_exceptions) Init(0) Optimization
1139 Delete dead instructions that may throw exceptions.
1141 fdelete-null-pointer-checks
1142 Common Report Var(flag_delete_null_pointer_checks) Init(-1) Optimization
1143 Delete useless null pointer checks.
1145 fdevirtualize-at-ltrans
1146 Common Report Var(flag_ltrans_devirtualize)
1147 Stream extra data to support more aggressive devirtualization in LTO local transformation mode.
1149 fdevirtualize-speculatively
1150 Common Report Var(flag_devirtualize_speculatively) Optimization
1151 Perform speculative devirtualization.
1154 Common Report Var(flag_devirtualize) Optimization
1155 Try to convert virtual calls to direct ones.
1157 fdiagnostics-show-location=
1158 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1159 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics.
1161 ; Required for these enum values.
1166 Name(diagnostic_prefixing_rule) Type(int)
1169 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1172 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1174 fdiagnostics-show-caret
1175 Common Var(flag_diagnostics_show_caret) Init(1)
1176 Show the source line with a caret indicating the column.
1179 Common Alias(fdiagnostics-color=,always,never)
1183 Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1184 -fdiagnostics-color=[never|always|auto] Colorize diagnostics.
1186 ; Required for these enum values.
1191 Name(diagnostic_color_rule) Type(int)
1194 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1197 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1200 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1202 fdiagnostics-parseable-fixits
1203 Common Var(flag_diagnostics_parseable_fixits)
1204 Print fixit hints in machine-readable form.
1206 fdiagnostics-generate-patch
1207 Common Var(flag_diagnostics_generate_patch)
1208 Print fix-it hints to stderr in unified diff format.
1210 fdiagnostics-show-option
1211 Common Var(flag_diagnostics_show_option) Init(1)
1212 Amend appropriate diagnostic messages with the command line option that controls them.
1215 Common Joined RejectNegative Var(common_deferred_options) Defer
1216 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass.
1219 Common Joined RejectNegative Var(common_deferred_options) Defer
1220 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass.
1223 Common Joined RejectNegative Var(common_deferred_options) Defer
1224 -fdump-<type> Dump various compiler internals to a file.
1227 Driver RejectNegative
1230 Common RejectNegative Joined Var(flag_dump_final_insns)
1231 -fdump-final-insns=filename Dump to filename the insns at the end of translation.
1234 Common RejectNegative Joined Var(flag_dump_go_spec)
1235 -fdump-go-spec=filename Write all declarations to file as Go code.
1238 Common Report Var(flag_dump_noaddr)
1239 Suppress output of addresses in debugging dumps.
1242 Common Driver Var(flag_report_bug)
1243 Collect and dump debug information into temporary file if ICE in C/C++
1246 fdump-internal-locations
1247 Common Var(flag_dump_locations) Init(0)
1248 Dump detailed information on GCC's internal representation of source code locations.
1251 Common Var(flag_dump_passes) Init(0)
1252 Dump optimization passes.
1255 Common Report Var(flag_dump_unnumbered)
1256 Suppress output of instruction numbers, line number notes and addresses in debugging dumps.
1258 fdump-unnumbered-links
1259 Common Report Var(flag_dump_unnumbered_links)
1260 Suppress output of previous and next insn numbers in debugging dumps.
1263 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1264 Enable CFI tables via GAS assembler directives.
1267 Common Report Var(flag_early_inlining) Init(1) Optimization
1268 Perform early inlining.
1270 feliminate-dwarf2-dups
1271 Common Report Var(flag_eliminate_dwarf2_dups)
1272 Perform DWARF duplicate elimination.
1275 Common Report Var(flag_ipa_sra) Init(0) Optimization
1276 Perform interprocedural reduction of aggregates.
1278 feliminate-unused-debug-symbols
1279 Common Report Var(flag_debug_only_used_symbols)
1280 Perform unused symbol elimination in debug info.
1282 feliminate-unused-debug-types
1283 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1284 Perform unused type elimination in debug info.
1286 femit-class-debug-always
1287 Common Report Var(flag_emit_class_debug_always) Init(0)
1288 Do not suppress C++ class debug information.
1291 Common Report Var(flag_exceptions) Optimization
1292 Enable exception handling.
1294 fexpensive-optimizations
1295 Common Report Var(flag_expensive_optimizations) Optimization
1296 Perform a number of minor, expensive optimizations.
1299 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1300 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision.
1303 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1306 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1309 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1315 Common Var(flag_fat_lto_objects)
1316 Output lto objects containing both the intermediate language and binary output.
1319 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1320 Assume no NaNs or infinities are generated.
1323 Common Joined RejectNegative Var(common_deferred_options) Defer
1324 -ffixed-<register> Mark <register> as being unavailable to the compiler.
1327 Common Report Var(flag_float_store) Optimization
1328 Don't allocate floats and doubles in extended-precision registers.
1332 Does nothing. Preserved for backward compatibility.
1335 Common Report Var(flag_forward_propagate) Optimization
1336 Perform a forward propagation pass on RTL.
1339 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization
1340 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1343 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1346 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1348 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1350 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1353 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1355 ffp-int-builtin-inexact
1356 Common Report Var(flag_fp_int_builtin_inexact) Init(1) Optimization
1357 Allow built-in functions ceil, floor, round, trunc to raise \"inexact\" exceptions.
1359 ; Nonzero means don't put addresses of constant functions in registers.
1360 ; Used for compiling the Unix kernel, where strange substitutions are
1361 ; done on the assembly output.
1363 Common Report Var(flag_no_function_cse,0) Optimization
1364 Allow function addresses to be held in registers.
1367 Common Report Var(flag_function_sections)
1368 Place each function into its own section.
1371 Common Report Var(flag_gcse) Optimization
1372 Perform global common subexpression elimination.
1375 Common Report Var(flag_gcse_lm) Init(1) Optimization
1376 Perform enhanced load motion during global common subexpression elimination.
1379 Common Report Var(flag_gcse_sm) Init(0) Optimization
1380 Perform store motion after global common subexpression elimination.
1383 Common Report Var(flag_gcse_las) Init(0) Optimization
1384 Perform redundant load after store elimination in global common subexpression
1388 Common Report Var(flag_gcse_after_reload) Optimization
1389 Perform global common subexpression elimination after register allocation has
1393 Name(dwarf_gnat_encodings) Type(int)
1396 Enum(dwarf_gnat_encodings) String(all) Value(DWARF_GNAT_ENCODINGS_ALL)
1399 Enum(dwarf_gnat_encodings) String(gdb) Value(DWARF_GNAT_ENCODINGS_GDB)
1402 Enum(dwarf_gnat_encodings) String(minimal) Value(DWARF_GNAT_ENCODINGS_MINIMAL)
1405 Common Enum(dwarf_gnat_encodings) Joined RejectNegative Report Undocumented Var(gnat_encodings)
1406 -fgnat-encodings=[all|gdb|minimal] Select the balance between GNAT encodings and standard DWARF emitted in the debug information
1408 ; This option is not documented yet as its semantics will change.
1410 Common Report Var(flag_graphite) Optimization
1411 Enable in and out of Graphite representation.
1414 Common Report Var(flag_graphite_identity) Optimization
1415 Enable Graphite Identity transformation.
1417 fhoist-adjacent-loads
1418 Common Report Var(flag_hoist_adjacent_loads) Optimization
1419 Enable hoisting adjacent loads to encourage generating conditional move
1423 Common Undocumented Report Var(flag_keep_gc_roots_live) Optimization
1424 ; Always keep a pointer to a live memory block
1426 floop-parallelize-all
1427 Common Report Var(flag_loop_parallelize_all) Optimization
1428 Mark all loops as parallel.
1431 Common Alias(floop-nest-optimize)
1432 Enable loop nest transforms. Same as -floop-nest-optimize.
1435 Common Alias(floop-nest-optimize)
1436 Enable loop nest transforms. Same as -floop-nest-optimize.
1439 Common Alias(floop-nest-optimize)
1440 Enable loop nest transforms. Same as -floop-nest-optimize.
1442 floop-unroll-and-jam
1443 Common Alias(floop-nest-optimize)
1444 Enable loop nest transforms. Same as -floop-nest-optimize.
1447 Common Report Var(flag_tm)
1448 Enable support for GNU transactional memory.
1451 Common Report Var(flag_gnu_unique) Init(1)
1452 Use STB_GNU_UNIQUE if supported by the assembler.
1456 Does nothing. Preserved for backward compatibility.
1459 Common Report Var(flag_loop_nest_optimize) Optimization
1460 Enable the loop nest optimizer.
1462 fstrict-volatile-bitfields
1463 Common Report Var(flag_strict_volatile_bitfields) Init(-1) Optimization
1464 Force bitfield accesses to match their type width.
1467 Common Report Var(flag_store_merging) Optimization
1468 Merge adjacent stores.
1470 fguess-branch-probability
1471 Common Report Var(flag_guess_branch_prob) Optimization
1472 Enable guessing of branch probabilities.
1474 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1475 ; Generate position-independent code for executables if possible
1476 ; On SVR4 targets, it also controls whether or not to emit a
1477 ; string identifying the compiler.
1479 Common Report Var(flag_no_ident,0)
1480 Process #ident directives.
1483 Common Report Var(flag_if_conversion) Optimization
1484 Perform conversion of conditional jumps to branchless equivalents.
1487 Common Report Var(flag_if_conversion2) Optimization
1488 Perform conversion of conditional jumps to conditional execution.
1491 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization
1492 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1495 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1498 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1501 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1504 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1506 ftree-loop-if-convert
1507 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1508 Convert conditional jumps in innermost loops to branchless equivalents.
1510 ftree-loop-if-convert-stores
1511 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1512 Also if-convert conditional jumps containing memory writes.
1514 ; -finhibit-size-directive inhibits output of .size for ELF.
1515 ; This is used only for compiling crtstuff.c,
1516 ; and it may be extended to other effects
1517 ; needed for crtstuff.c on other systems.
1518 finhibit-size-directive
1519 Common Report Var(flag_inhibit_size_directive)
1520 Do not generate .size directives.
1523 Common Report Var(flag_indirect_inlining) Optimization
1524 Perform indirect inlining.
1526 ; General flag to enable inlining. Specifying -fno-inline will disable
1527 ; all inlining apart from always-inline functions.
1529 Common Report Var(flag_no_inline,0) Init(0) Optimization
1530 Enable inlining of function declared \"inline\", disabling disables all inlining.
1532 finline-small-functions
1533 Common Report Var(flag_inline_small_functions) Optimization
1534 Integrate functions into their callers when code size is known not to grow.
1537 Common Report Var(flag_inline_functions) Optimization
1538 Integrate functions not declared \"inline\" into their callers when profitable.
1540 finline-functions-called-once
1541 Common Report Var(flag_inline_functions_called_once) Optimization
1542 Integrate functions only required by their single caller.
1545 Common RejectNegative Joined Alias(finline-limit=)
1548 Common RejectNegative Joined UInteger
1549 -finline-limit=<number> Limit the size of inlined functions to <number>.
1552 Common Report Var(flag_inline_atomics) Init(1) Optimization
1553 Inline __atomic operations when a lock free instruction sequence is available.
1555 finstrument-functions
1556 Common Report Var(flag_instrument_function_entry_exit)
1557 Instrument function entry and exit with profiling calls.
1559 finstrument-functions-exclude-function-list=
1560 Common RejectNegative Joined
1561 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions.
1563 finstrument-functions-exclude-file-list=
1564 Common RejectNegative Joined
1565 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files.
1568 Common Report Var(flag_ipa_cp) Optimization
1569 Perform interprocedural constant propagation.
1572 Common Report Var(flag_ipa_cp_clone) Optimization
1573 Perform cloning to make Interprocedural constant propagation stronger.
1576 Common Report Var(flag_ipa_cp_alignment) Optimization
1577 Perform alignment discovery and propagation to make Interprocedural constant propagation stronger.
1580 Common Report Var(flag_ipa_bit_cp) Optimization
1581 Perform interprocedural bitwise constant propagation.
1584 Common Report Var(flag_ipa_profile) Init(0) Optimization
1585 Perform interprocedural profile propagation.
1588 Common Report Var(flag_ipa_pta) Init(0) Optimization
1589 Perform interprocedural points-to analysis.
1592 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1593 Discover pure and const functions.
1596 Common Report Var(flag_ipa_icf) Optimization
1597 Perform Identical Code Folding for functions and read-only variables.
1600 Common Report Var(flag_ipa_icf_functions) Optimization
1601 Perform Identical Code Folding for functions.
1604 Common Report Var(flag_ipa_icf_variables) Optimization
1605 Perform Identical Code Folding for variables.
1608 Common Report Var(flag_ipa_reference) Init(0) Optimization
1609 Discover readonly and non addressable static variables.
1613 Does nothing. Preserved for backward compatibility.
1617 Does nothing. Preserved for backward compatibility.
1620 Common Report Var(flag_ipa_vrp) Optimization
1621 Perform IPA Value Range Propagation.
1624 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization
1625 -fira-algorithm=[CB|priority] Set the used IRA algorithm.
1628 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1631 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1634 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1637 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT) Optimization
1638 -fira-region=[one|all|mixed] Set regions for IRA.
1641 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1644 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1647 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1650 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1653 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1654 Use IRA based register pressure calculation
1655 in RTL hoist optimizations.
1658 Common Report Var(flag_ira_loop_pressure) Optimization
1659 Use IRA based register pressure calculation
1660 in RTL loop optimizations.
1662 fira-share-save-slots
1663 Common Report Var(flag_ira_share_save_slots) Init(1) Optimization
1664 Share slots for saving different hard registers.
1666 fira-share-spill-slots
1667 Common Report Var(flag_ira_share_spill_slots) Init(1) Optimization
1668 Share stack slots for spilled pseudo-registers.
1671 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1672 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1675 Common Report Var(flag_ivopts) Init(1) Optimization
1676 Optimize induction variables on trees.
1679 Common Var(flag_jump_tables) Init(1) Optimization
1680 Use jump tables for sufficiently large switch statements.
1682 fkeep-inline-functions
1683 Common Report Var(flag_keep_inline_functions)
1684 Generate code for functions even if they are fully inlined.
1686 fkeep-static-functions
1687 Common Report Var(flag_keep_static_functions)
1688 Generate code for static functions even if they are never called.
1691 Common Report Var(flag_keep_static_consts) Init(1)
1692 Emit static const variables even if they are not used.
1695 Common Report Var(flag_leading_underscore) Init(-1)
1696 Give external symbols a leading underscore.
1700 Does nothing. Preserved for backward compatibility.
1703 Common Report Var(flag_lra_remat) Optimization
1704 Do CFG-sensitive rematerialization in LRA.
1708 Enable link-time optimization.
1711 Common RejectNegative Joined Var(flag_lto)
1712 Link-time optimization with number of parallel jobs or jobserver.
1715 Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
1718 Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
1721 Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
1724 Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
1727 Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
1730 Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
1733 Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)
1734 Specify the algorithm to partition symbols and vars at linktime.
1736 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1737 flto-compression-level=
1738 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1739 -flto-compression-level=<number> Use zlib compression level <number> for IL.
1741 flto-odr-type-merging
1742 Common Report Var(flag_lto_odr_type_mering) Init(1)
1743 Merge C++ types using One Definition Rule.
1746 Common Report Var(flag_lto_report) Init(0)
1747 Report various link-time optimization statistics.
1750 Common Report Var(flag_lto_report_wpa) Init(0)
1751 Report various link-time optimization statistics for WPA only.
1754 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1755 Set errno after built-in math functions.
1758 Common Joined RejectNegative UInteger Var(flag_max_errors)
1759 -fmax-errors=<number> Maximum number of errors to report.
1762 Common Report Var(mem_report)
1763 Report on permanent memory allocation.
1766 Common Report Var(mem_report_wpa)
1767 Report on permanent memory allocation in WPA only.
1769 ; This will attempt to merge constant section constants, if 1 only
1770 ; string constants and constants from constant pool, if 2 also constant
1772 fmerge-all-constants
1773 Common Report Var(flag_merge_constants,2) Init(1)
1774 Attempt to merge identical constants and constant variables.
1777 Common Report Var(flag_merge_constants,1)
1778 Attempt to merge identical constants across compilation units.
1780 fmerge-debug-strings
1781 Common Report Var(flag_merge_debug_strings) Init(1)
1782 Attempt to merge identical debug strings across compilation units.
1785 Common RejectNegative Joined UInteger
1786 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping.
1789 Common Report Var(flag_modulo_sched) Optimization
1790 Perform SMS based modulo scheduling before the first scheduling pass.
1792 fmodulo-sched-allow-regmoves
1793 Common Report Var(flag_modulo_sched_allow_regmoves) Optimization
1794 Perform SMS based modulo scheduling with register moves allowed.
1796 fmove-loop-invariants
1797 Common Report Var(flag_move_loop_invariants) Optimization
1798 Move loop invariant computations out of loops.
1801 Common Var(flag_dce) Init(1) Optimization
1802 Use the RTL dead code elimination pass.
1805 Common Var(flag_dse) Init(1) Optimization
1806 Use the RTL dead store elimination pass.
1808 freschedule-modulo-scheduled-loops
1809 Common Report Var(flag_resched_modulo_sched) Optimization
1810 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling.
1812 fnon-call-exceptions
1813 Common Report Var(flag_non_call_exceptions) Optimization
1814 Support synchronous non-call exceptions.
1817 Common Driver Joined MissingArgError(options or targets missing after %qs)
1818 -foffload=<targets>=<options> Specify offloading targets and options for them.
1821 Common Joined RejectNegative Enum(offload_abi) Var(flag_offload_abi) Init(OFFLOAD_ABI_UNSET)
1822 -foffload-abi=[lp64|ilp32] Set the ABI to use in an offload compiler.
1825 Name(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs)
1828 Enum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32)
1831 Enum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64)
1834 Common Report Var(flag_omit_frame_pointer) Optimization
1835 When possible do not generate stack frames.
1838 Common Report Var(flag_opt_info) Optimization
1839 Enable all optimization info dumps on stderr.
1842 Common Joined RejectNegative Var(common_deferred_options) Defer
1843 -fopt-info[-<type>=filename] Dump compiler optimization details.
1845 foptimize-register-move
1847 Does nothing. Preserved for backward compatibility.
1849 foptimize-sibling-calls
1850 Common Report Var(flag_optimize_sibling_calls) Optimization
1851 Optimize sibling and tail recursive calls.
1854 Common Report Var(flag_partial_inlining) Optimization
1855 Perform partial inlining.
1858 Common Report Var(pre_ipa_mem_report)
1859 Report on memory allocation before interprocedural optimization.
1861 fpost-ipa-mem-report
1862 Common Report Var(post_ipa_mem_report)
1863 Report on memory allocation before interprocedural optimization.
1866 Common Report Var(flag_pack_struct) Optimization
1867 Pack structure members together without holes.
1870 Common RejectNegative Joined UInteger Optimization
1871 -fpack-struct=<number> Set initial maximum structure member alignment.
1874 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1875 Return small aggregates in memory, not registers.
1878 Common Report Var(flag_peel_loops) Optimization
1879 Perform loop peeling.
1882 Common Report Var(flag_no_peephole,0) Optimization
1883 Enable machine specific peephole optimizations.
1886 Common Report Var(flag_peephole2) Optimization
1887 Enable an RTL peephole pass before sched2.
1890 Common Report Var(flag_pic,2) Negative(fPIE) Init(-1)
1891 Generate position-independent code if possible (large mode).
1894 Common Report Var(flag_pie,2) Negative(fpic) Init(-1)
1895 Generate position-independent code for executables if possible (large mode).
1898 Common Report Var(flag_pic,1) Negative(fpie) Init(-1)
1899 Generate position-independent code if possible (small mode).
1902 Common Report Var(flag_pie,1) Negative(fPIC) Init(-1)
1903 Generate position-independent code for executables if possible (small mode).
1906 Common Report Var(flag_plt) Init(1) Optimization
1907 Use PLT for PIC calls (-fno-plt: load the address from GOT at call site).
1910 Common Joined RejectNegative Var(common_deferred_options) Defer
1911 Specify a plugin to load.
1914 Common Joined RejectNegative Var(common_deferred_options) Defer
1915 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>.
1917 fpredictive-commoning
1918 Common Report Var(flag_predictive_commoning) Optimization
1919 Run predictive commoning optimization.
1921 fprefetch-loop-arrays
1922 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1923 Generate prefetch instructions, if available, for arrays in loops.
1926 Common Report Var(profile_flag)
1927 Enable basic program profiling code.
1930 Common Report Var(profile_arc_flag)
1931 Insert arc-based program profiling code.
1934 Common Joined RejectNegative Var(profile_data_prefix)
1935 Set the top-level directory for storing the profile data.
1936 The default is 'pwd'.
1939 Common Report Var(flag_profile_correction)
1940 Enable correction of flow inconsistent profile data input.
1943 Common Joined RejectNegative Enum(profile_update) Var(flag_profile_update) Init(PROFILE_UPDATE_SINGLE)
1944 -fprofile-update=[single|atomic] Set the profile update method.
1947 Name(profile_update) Type(enum profile_update) UnknownError(unknown profile update method %qs)
1950 Enum(profile_update) String(single) Value(PROFILE_UPDATE_SINGLE)
1953 Enum(profile_update) String(atomic) Value(PROFILE_UPDATE_ATOMIC)
1957 Enable common options for generating profile info for profile feedback directed optimizations.
1960 Common Joined RejectNegative
1961 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=.
1964 Common Var(flag_profile_use)
1965 Enable common options for performing profile feedback directed optimizations.
1968 Common Joined RejectNegative
1969 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=.
1972 Common Report Var(flag_profile_values)
1973 Insert code to profile values of expressions.
1976 Common Report Var(profile_report)
1977 Report on consistency of profile.
1979 fprofile-reorder-functions
1980 Common Report Var(flag_profile_reorder_functions)
1981 Enable function reordering that improves code placement.
1984 Common Var(common_deferred_options) Defer
1987 Common Joined RejectNegative Var(common_deferred_options) Defer
1988 -frandom-seed=<string> Make compile reproducible using <string>.
1990 ; This switch causes the command line that was used to create an
1991 ; object file to be recorded into the object file. The exact format
1992 ; of this recording is target and binary file format dependent.
1993 ; It is related to the -fverbose-asm switch, but that switch only
1994 ; records information in the assembler output file as comments, so
1995 ; they never reach the object file.
1996 frecord-gcc-switches
1997 Common Report Var(flag_record_gcc_switches)
1998 Record gcc command line switches in the object file.
2001 Common Report Var(flag_pcc_struct_return,0) Optimization
2002 Return small aggregates in registers.
2006 Does nothing. Preserved for backward compatibility.
2009 Common Report Var(flag_lifetime_dse,2) Init(2) Optimization
2010 Tell DSE that the storage for a C++ object is dead when the constructor
2011 starts and when the destructor finishes.
2014 Common Joined RejectNegative UInteger Var(flag_lifetime_dse) Optimization
2016 flive-range-shrinkage
2017 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
2018 Relief of register pressure through live range shrinkage.
2021 Common Report Var(flag_rename_registers) Init(2) Optimization
2022 Perform a register renaming optimization pass.
2025 Common Report Var(flag_schedule_fusion) Init(2) Optimization
2026 Perform a target dependent instruction fusion optimization pass.
2029 Common Report Var(flag_reorder_blocks) Optimization
2030 Reorder basic blocks to improve code placement.
2032 freorder-blocks-algorithm=
2033 Common Joined RejectNegative Enum(reorder_blocks_algorithm) Var(flag_reorder_blocks_algorithm) Init(REORDER_BLOCKS_ALGORITHM_SIMPLE) Optimization
2034 -freorder-blocks-algorithm=[simple|stc] Set the used basic block reordering algorithm.
2037 Name(reorder_blocks_algorithm) Type(enum reorder_blocks_algorithm) UnknownError(unknown basic block reordering algorithm %qs)
2040 Enum(reorder_blocks_algorithm) String(simple) Value(REORDER_BLOCKS_ALGORITHM_SIMPLE)
2043 Enum(reorder_blocks_algorithm) String(stc) Value(REORDER_BLOCKS_ALGORITHM_STC)
2045 freorder-blocks-and-partition
2046 Common Report Var(flag_reorder_blocks_and_partition) Optimization
2047 Reorder basic blocks and partition into hot and cold sections.
2050 Common Report Var(flag_reorder_functions) Optimization
2051 Reorder functions to improve code placement.
2053 frerun-cse-after-loop
2054 Common Report Var(flag_rerun_cse_after_loop) Optimization
2055 Add a common subexpression elimination pass after loop optimizations.
2059 Does nothing. Preserved for backward compatibility.
2062 Common Report Var(flag_rounding_math) Optimization SetByCombined
2063 Disable optimizations that assume default FP rounding behavior.
2066 Common Report Var(flag_schedule_interblock) Init(1) Optimization
2067 Enable scheduling across basic blocks.
2070 Common Report Var(flag_sched_pressure) Init(0) Optimization
2071 Enable register pressure sensitive insn scheduling.
2074 Common Report Var(flag_schedule_speculative) Init(1) Optimization
2075 Allow speculative motion of non-loads.
2078 Common Report Var(flag_schedule_speculative_load) Optimization
2079 Allow speculative motion of some loads.
2081 fsched-spec-load-dangerous
2082 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
2083 Allow speculative motion of more loads.
2086 Common RejectNegative Joined UInteger Var(sched_verbose_param) Init(1)
2087 -fsched-verbose=<number> Set the verbosity level of the scheduler.
2089 fsched2-use-superblocks
2090 Common Report Var(flag_sched2_use_superblocks) Optimization
2091 If scheduling post reload, do superblock scheduling.
2095 Does nothing. Preserved for backward compatibility.
2098 Common Report Var(flag_schedule_insns) Optimization
2099 Reschedule instructions before register allocation.
2102 Common Report Var(flag_schedule_insns_after_reload) Optimization
2103 Reschedule instructions after register allocation.
2105 ; This flag should be on when a target implements non-trivial
2106 ; scheduling hooks, maybe saving some information for its own sake.
2107 ; On IA64, for example, this is used for correct bundling.
2108 fselective-scheduling
2109 Common Report Var(flag_selective_scheduling) Optimization
2110 Schedule instructions using selective scheduling algorithm.
2112 fselective-scheduling2
2113 Common Report Var(flag_selective_scheduling2) Optimization
2114 Run selective scheduling after reload.
2117 Common Undocumented Var(flag_self_test)
2120 fsel-sched-pipelining
2121 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
2122 Perform software pipelining of inner loops during selective scheduling.
2124 fsel-sched-pipelining-outer-loops
2125 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
2126 Perform software pipelining of outer loops during selective scheduling.
2128 fsel-sched-reschedule-pipelined
2129 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
2130 Reschedule pipelined regions without pipelining.
2132 fsemantic-interposition
2133 Common Report Var(flag_semantic_interposition) Init(1)
2134 Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker.
2136 ; sched_stalled_insns means that insns can be moved prematurely from the queue
2137 ; of stalled insns into the ready list.
2138 fsched-stalled-insns
2139 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
2140 Allow premature scheduling of queued insns.
2142 fsched-stalled-insns=
2143 Common RejectNegative Joined UInteger Optimization
2144 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled.
2146 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
2147 ; be examined for a dependency on a stalled insn that is candidate for
2148 ; premature removal from the queue of stalled insns into the ready list (has
2149 ; an effect only if the flag 'sched_stalled_insns' is set).
2150 fsched-stalled-insns-dep
2151 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
2152 Set dependence distance checking in premature scheduling of queued insns.
2154 fsched-stalled-insns-dep=
2155 Common RejectNegative Joined UInteger Optimization
2156 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns.
2158 fsched-group-heuristic
2159 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
2160 Enable the group heuristic in the scheduler.
2162 fsched-critical-path-heuristic
2163 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
2164 Enable the critical path heuristic in the scheduler.
2166 fsched-spec-insn-heuristic
2167 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
2168 Enable the speculative instruction heuristic in the scheduler.
2170 fsched-rank-heuristic
2171 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
2172 Enable the rank heuristic in the scheduler.
2174 fsched-last-insn-heuristic
2175 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
2176 Enable the last instruction heuristic in the scheduler.
2178 fsched-dep-count-heuristic
2179 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
2180 Enable the dependent count heuristic in the scheduler.
2183 Common Report Var(flag_section_anchors) Optimization
2184 Access data in the same section from shared anchor points.
2188 Does nothing. Preserved for backward compatibility.
2192 Does nothing. Preserved for backward compatibility.
2195 Common Report Var(flag_ree) Init(0)
2196 Turn on Redundant Extensions Elimination pass.
2199 Common Report Var(flag_show_column) Init(1)
2200 Show column numbers in diagnostics, when available. Default on.
2203 Common Report Var(flag_shrink_wrap) Optimization
2204 Emit function prologues only before parts of the function that need it,
2205 rather than at the top of the function.
2207 fshrink-wrap-separate
2208 Common Report Var(flag_shrink_wrap_separate) Init(1) Optimization
2209 Shrink-wrap parts of the prologue and epilogue separately.
2212 Common Report Var(flag_signaling_nans) Optimization SetByCombined
2213 Disable optimizations observable by IEEE signaling NaNs.
2216 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
2217 Disable floating point optimizations that ignore the IEEE signedness of zero.
2219 fsingle-precision-constant
2220 Common Report Var(flag_single_precision_constant) Optimization
2221 Convert floating point constants to single precision constants.
2223 fsplit-ivs-in-unroller
2224 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
2225 Split lifetimes of induction variables when loops are unrolled.
2228 Common Report Var(flag_split_stack) Init(-1)
2229 Generate discontiguous stack frames.
2232 Common Report Var(flag_split_wide_types) Optimization
2233 Split wide types into independent registers.
2236 Common Report Var(flag_ssa_backprop) Init(1) Optimization
2237 Enable backward propagation of use properties at the SSA level.
2240 Common Report Var(flag_ssa_phiopt) Optimization
2241 Optimize conditional patterns using SSA PHI nodes.
2244 Common Report Var(flag_stdarg_opt) Init(1) Optimization
2245 Optimize amount of stdarg registers saved to stack at start of function.
2247 fvariable-expansion-in-unroller
2248 Common Report Var(flag_variable_expansion_in_unroller) Optimization
2249 Apply variable expansion when loops are unrolled.
2252 Common Report RejectNegative Joined
2253 -fstack-check=[no|generic|specific] Insert stack checking code into the program.
2256 Common Alias(fstack-check=, specific, no)
2257 Insert stack checking code into the program. Same as -fstack-check=specific.
2260 Common Var(common_deferred_options) Defer
2262 fstack-limit-register=
2263 Common RejectNegative Joined Var(common_deferred_options) Defer
2264 -fstack-limit-register=<register> Trap if the stack goes past <register>.
2266 fstack-limit-symbol=
2267 Common RejectNegative Joined Var(common_deferred_options) Defer
2268 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>.
2271 Common Report Var(flag_stack_protect, 1) Init(-1) Optimization
2272 Use propolice as a stack protection method.
2274 fstack-protector-all
2275 Common Report RejectNegative Var(flag_stack_protect, 2) Init(-1) Optimization
2276 Use a stack protection method for every function.
2278 fstack-protector-strong
2279 Common Report RejectNegative Var(flag_stack_protect, 3) Init(-1) Optimization
2280 Use a smart stack protection method for certain functions.
2282 fstack-protector-explicit
2283 Common Report RejectNegative Var(flag_stack_protect, 4) Optimization
2284 Use stack protection method only for functions with the stack_protect attribute.
2287 Common RejectNegative Var(flag_stack_usage)
2288 Output stack usage information on a per-function basis.
2292 Does nothing. Preserved for backward compatibility.
2294 ; Nonzero if we should do (language-dependent) alias analysis.
2295 ; Typically, this analysis will assume that expressions of certain
2296 ; types do not alias expressions of certain other types. Only used
2297 ; if alias analysis (in general) is enabled.
2299 Common Report Var(flag_strict_aliasing) Optimization
2300 Assume strict aliasing rules apply.
2303 Common Report Var(flag_strict_overflow) Optimization
2304 Treat signed overflow as undefined.
2307 Common Report Var(flag_sync_libcalls) Init(1)
2308 Implement __atomic operations via libcalls to legacy __sync functions.
2311 Common Report Var(flag_syntax_only)
2312 Check for syntax errors, then stop.
2315 Common Report Var(flag_test_coverage)
2316 Create data files needed by \"gcov\".
2319 Common Report Var(flag_thread_jumps) Optimization
2320 Perform jump threading optimizations.
2323 Common Report Var(time_report)
2324 Report the time taken by each compiler pass.
2326 ftime-report-details
2327 Common Report Var(time_report_details)
2328 Record times taken by sub-phases separately.
2331 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2332 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model.
2335 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2338 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2341 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2344 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2347 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2350 Common Report Var(flag_toplevel_reorder) Init(2)
2351 Reorder top level functions, variables, and asms.
2354 Common Report Var(flag_tracer) Optimization
2355 Perform superblock formation via tail duplication.
2358 Common Report Var(flag_trampolines) Init(0)
2359 For targets that normally need trampolines for nested functions, always
2360 generate them instead of using descriptors.
2362 ; Zero means that floating-point math operations cannot generate a
2363 ; (user-visible) trap. This is the case, for example, in nonstop
2364 ; IEEE 754 arithmetic.
2366 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2367 Assume floating-point operations can trap.
2370 Common Report Var(flag_trapv) Optimization
2371 Trap for signed overflow in addition, subtraction and multiplication.
2374 Common Report Var(flag_tree_ccp) Optimization
2375 Enable SSA-CCP optimization on trees.
2378 Common Report Var(flag_tree_bit_ccp) Optimization
2379 Enable SSA-BIT-CCP optimization on trees.
2383 Does nothing. Preserved for backward compatibility.
2386 Common Report Var(flag_tree_ch) Optimization
2387 Enable loop header copying on trees.
2389 ftree-coalesce-inlined-vars
2390 Common Ignore RejectNegative
2391 Does nothing. Preserved for backward compatibility.
2394 Common Report Var(flag_tree_coalesce_vars) Optimization
2395 Enable SSA coalescing of user variables.
2399 Does nothing. Preserved for backward compatibility.
2402 Common Report Var(flag_tree_copy_prop) Optimization
2403 Enable copy propagation on trees.
2405 ftree-store-copy-prop
2407 Does nothing. Preserved for backward compatibility.
2410 Common Report Var(flag_tree_cselim) Init(2) Optimization
2411 Transform condition stores into unconditional ones.
2413 ftree-switch-conversion
2414 Common Report Var(flag_tree_switch_conversion) Optimization
2415 Perform conversions of switch initializations.
2418 Common Report Var(flag_tree_dce) Optimization
2419 Enable SSA dead code elimination optimization on trees.
2421 ftree-dominator-opts
2422 Common Report Var(flag_tree_dom) Optimization
2423 Enable dominator optimizations.
2426 Common Report Var(flag_tree_tail_merge) Optimization
2427 Enable tail merging on trees.
2430 Common Report Var(flag_tree_dse) Optimization
2431 Enable dead store elimination.
2434 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2435 Enable forward propagation on trees.
2438 Common Report Var(flag_tree_fre) Optimization
2439 Enable Full Redundancy Elimination (FRE) on trees.
2442 Common Report Var(flag_optimize_strlen) Optimization
2443 Enable string length optimizations on trees.
2445 fisolate-erroneous-paths-dereference
2446 Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization
2447 Detect paths that trigger erroneous or undefined behavior due to
2448 dereferencing a null pointer. Isolate those paths from the main control
2449 flow and turn the statement with erroneous or undefined behavior into a trap.
2451 fisolate-erroneous-paths-attribute
2452 Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization
2453 Detect paths that trigger erroneous or undefined behavior due a null value
2454 being used in a way forbidden by a returns_nonnull or nonnull
2455 attribute. Isolate those paths from the main control flow and turn the
2456 statement with erroneous or undefined behavior into a trap.
2458 ftree-loop-distribution
2459 Common Report Var(flag_tree_loop_distribution) Optimization
2460 Enable loop distribution on trees.
2462 ftree-loop-distribute-patterns
2463 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2464 Enable loop distribution for patterns transformed into a library call.
2467 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2468 Enable loop invariant motion on trees.
2471 Common Alias(floop-nest-optimize)
2472 Enable loop nest transforms. Same as -floop-nest-optimize.
2475 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2476 Create canonical induction variables in loops.
2479 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2480 Enable loop optimizations on tree level.
2482 ftree-parallelize-loops=
2483 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) Optimization
2484 Enable automatic parallelization of loops.
2487 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2488 Enable hoisting loads from conditional pointers.
2491 Common Report Var(flag_tree_pre) Optimization
2492 Enable SSA-PRE optimization on trees.
2495 Common Report Var(flag_tree_partial_pre) Optimization
2496 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination.
2499 Common Report Var(flag_tree_pta) Optimization
2500 Perform function-local points-to analysis on trees.
2503 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2504 Enable reassociation on tree level.
2508 Does nothing. Preserved for backward compatibility.
2511 Common Report Var(flag_tree_sink) Optimization
2512 Enable SSA code sinking on trees.
2515 Common Report Var(flag_tree_slsr) Optimization
2516 Perform straight-line strength reduction.
2519 Common Report Var(flag_tree_sra) Optimization
2520 Perform scalar replacement of aggregates.
2523 Common Report Var(flag_tree_ter) Optimization
2524 Replace temporary expressions in the SSA->normal pass.
2527 Common Report Var(flag_tree_live_range_split) Optimization
2528 Perform live range splitting during the SSA->normal pass.
2531 Common Report Var(flag_tree_vrp) Init(0) Optimization
2532 Perform Value Range Propagation on trees.
2535 Common Report Var(flag_split_paths) Init(0) Optimization
2536 Split paths leading to loop backedges.
2538 funconstrained-commons
2539 Common Var(flag_unconstrained_commons) Optimization
2540 Assume common declarations may be overridden with ones with a larger
2544 Common Report Var(flag_unit_at_a_time) Init(1)
2545 Compile whole compilation unit at a time.
2548 Common Report Var(flag_unroll_loops) Optimization
2549 Perform loop unrolling when iteration count is known.
2552 Common Report Var(flag_unroll_all_loops) Optimization
2553 Perform loop unrolling for all loops.
2555 ; Nonzero means that loop optimizer may assume that the induction variables
2556 ; that control loops do not overflow and that the loops with nontrivial
2557 ; exit condition are not infinite
2558 funsafe-loop-optimizations
2560 Does nothing. Preserved for backward compatibility.
2563 Common Report Var(flag_associative_math) SetByCombined Optimization
2564 Allow optimization for floating-point arithmetic which may change the
2565 result of the operation due to rounding.
2568 Common Report Var(flag_reciprocal_math) SetByCombined Optimization
2569 Same as -fassociative-math for expressions which include division.
2571 ; Nonzero means that unsafe floating-point math optimizations are allowed
2572 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2573 ; are allowed to assume that their arguments and results are "normal"
2574 ; (e.g., nonnegative for SQRT).
2575 funsafe-math-optimizations
2576 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2577 Allow math optimizations that may violate IEEE or ISO standards.
2580 Common Report Var(flag_unswitch_loops) Optimization
2581 Perform loop unswitching.
2584 Common Report Var(flag_split_loops) Optimization
2585 Perform loop splitting.
2588 Common Report Var(flag_unwind_tables) Optimization
2589 Just generate unwind tables for exception handling.
2592 Common Driver Negative(fuse-ld=gold)
2593 Use the bfd linker instead of the default linker.
2596 Common Driver Negative(fuse-ld=bfd)
2597 Use the gold linker instead of the default linker.
2600 Common Undocumented Var(flag_use_linker_plugin)
2602 ; Positive if we should track variables, negative if we should run
2603 ; the var-tracking pass only to discard debug annotations, zero if
2604 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2605 ; will be set according to optimize, debug_info_level and debug_hooks
2606 ; in process_options ().
2608 Common Report Var(flag_var_tracking) Init(2) Optimization
2609 Perform variable tracking.
2611 ; Positive if we should track variables at assignments, negative if
2612 ; we should run the var-tracking pass only to discard debug
2613 ; annotations. When flag_var_tracking_assignments ==
2614 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2615 fvar-tracking-assignments
2616 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2617 Perform variable tracking by annotating assignments.
2619 ; Nonzero if we should toggle flag_var_tracking_assignments after
2620 ; processing options and computing its default. */
2621 fvar-tracking-assignments-toggle
2622 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2623 Toggle -fvar-tracking-assignments.
2625 ; Positive if we should track uninitialized variables, negative if
2626 ; we should run the var-tracking pass only to discard debug
2627 ; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
2628 ; will be set according to flag_var_tracking.
2629 fvar-tracking-uninit
2630 Common Report Var(flag_var_tracking_uninit) Optimization
2631 Perform variable tracking and also tag variables that are uninitialized.
2634 Common Report Var(flag_tree_vectorize) Optimization
2635 Enable vectorization on trees.
2637 ftree-vectorizer-verbose=
2638 Common Joined RejectNegative Ignore
2639 Does nothing. Preserved for backward compatibility.
2641 ftree-loop-vectorize
2642 Common Report Var(flag_tree_loop_vectorize) Optimization
2643 Enable loop vectorization on trees.
2646 Common Report Var(flag_tree_slp_vectorize) Optimization
2647 Enable basic block vectorization (SLP) on trees.
2650 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization
2651 Specifies the cost model for vectorization.
2654 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization
2655 Specifies the vectorization cost model for code marked with a simd directive.
2658 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2661 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2664 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2667 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2670 Common RejectNegative Alias(fvect-cost-model=,dynamic)
2671 Enables the dynamic vectorizer cost model. Preserved for backward compatibility.
2674 Common RejectNegative Alias(fvect-cost-model=,unlimited)
2675 Enables the unlimited vectorizer cost model. Preserved for backward compatibility.
2677 ftree-vect-loop-version
2679 Does nothing. Preserved for backward compatibility.
2682 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2683 Enable copy propagation of scalar-evolution information.
2685 ; -fverbose-asm causes extra commentary information to be produced in
2686 ; the generated assembly code (to make it more readable). This option
2687 ; is generally only of use to those who actually need to read the
2688 ; generated assembly code (perhaps while debugging the compiler itself).
2689 ; -fno-verbose-asm, the default, causes the extra information
2690 ; to not be added and is useful when comparing two assembler files.
2692 Common Report Var(flag_verbose_asm)
2693 Add extra commentary to assembler output.
2696 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2697 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility.
2700 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2703 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2706 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2709 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2712 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2715 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2716 Validate vtable pointers before using them.
2719 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2722 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2725 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2728 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2731 Common Var(flag_vtv_counts)
2732 Output vtable verification counters.
2735 Common Var(flag_vtv_debug)
2736 Output vtable verification pointer sets information.
2739 Common Report Var(flag_value_profile_transformations) Optimization
2740 Use expression value profiles in optimizations.
2743 Common Report Var(flag_web) Init(2) Optimization
2744 Construct webs and split unrelated uses of single variable.
2746 ftree-builtin-call-dce
2747 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2748 Enable conditional dead code elimination for builtin calls.
2751 Common Report Var(flag_whole_program) Init(0)
2752 Perform whole program optimizations.
2755 Common Report Var(flag_wrapv) Optimization
2756 Assume signed arithmetic overflow wraps around.
2758 fzero-initialized-in-bss
2759 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2760 Put zero initialized data in the bss section.
2763 Common JoinedOrMissing
2764 Generate debug information in default format.
2767 Common JoinedOrMissing Negative(gdwarf)
2768 Generate debug information in COFF format.
2771 Common JoinedOrMissing Negative(gdwarf-)
2772 Generate debug information in default version of DWARF format.
2775 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2776 Generate debug information in DWARF v2 (or later) format.
2779 Common JoinedOrMissing
2780 Generate debug information in default extended format.
2783 Common Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
2784 Don't generate DWARF pubnames and pubtypes sections.
2787 Common Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
2788 Generate DWARF pubnames and pubtypes sections.
2791 Common Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
2792 Generate DWARF pubnames and pubtypes sections with GNU extensions.
2794 gno-record-gcc-switches
2795 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2796 Don't record gcc command line switches in DWARF DW_AT_producer.
2798 grecord-gcc-switches
2799 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2800 Record gcc command line switches in DWARF DW_AT_producer.
2803 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2804 Don't generate debug information in separate .dwo files.
2807 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2808 Generate debug information in separate .dwo files.
2811 Common JoinedOrMissing Negative(gstabs+)
2812 Generate debug information in STABS format.
2815 Common JoinedOrMissing Negative(gvms)
2816 Generate debug information in extended STABS format.
2819 Common RejectNegative Var(dwarf_strict,0) Init(0)
2820 Emit DWARF additions beyond selected version.
2823 Common Report RejectNegative Var(dwarf_strict,1)
2824 Don't emit DWARF additions beyond selected version.
2827 Common Report Var(flag_gtoggle)
2828 Toggle debug information generation.
2831 Common JoinedOrMissing Negative(gxcoff)
2832 Generate debug information in VMS format.
2835 Common JoinedOrMissing Negative(gxcoff+)
2836 Generate debug information in XCOFF format.
2839 Common JoinedOrMissing Negative(gcoff)
2840 Generate debug information in extended XCOFF format.
2843 Name(compressed_debug_sections) Type(int)
2845 ; Since -gz= is completely handled in specs, the values aren't used and we
2846 ; assign arbitrary constants.
2848 Enum(compressed_debug_sections) String(none) Value(0)
2851 Enum(compressed_debug_sections) String(zlib) Value(1)
2854 Enum(compressed_debug_sections) String(zlib-gnu) Value(2)
2858 Generate compressed debug sections.
2861 Common Driver Joined Enum(compressed_debug_sections)
2862 -gz=<format> Generate compressed debug sections in format <format>.
2865 Driver Joined Separate
2868 Common Joined Var(plugindir_string) Init(0)
2869 -iplugindir=<dir> Set <dir> to be the default plugin directory.
2872 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2873 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory.
2876 Driver Joined Separate
2881 no-canonical-prefixes
2894 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2895 -o <file> Place output into <file>.
2898 Common Var(profile_flag)
2899 Enable function profiling.
2902 Driver Var(pass_exit_codes)
2905 Common Alias(Wpedantic)
2908 Common Var(flag_pedantic_errors)
2909 Like -pedantic but issue them as errors.
2915 Driver Var(use_pipes)
2918 Driver JoinedOrMissing Var(print_file_name)
2920 print-libgcc-file-name
2923 print-multi-directory
2924 Driver Var(print_multi_directory)
2927 Driver Var(print_multi_lib)
2929 print-multi-os-directory
2930 Driver Var(print_multi_os_directory)
2933 Driver Var(print_multiarch)
2936 Driver JoinedOrMissing Var(print_prog_name)
2939 Driver Var(print_search_dirs)
2942 Driver Var(print_sysroot)
2944 print-sysroot-headers-suffix
2945 Driver Var(print_sysroot_headers_suffix)
2948 Common Var(quiet_flag) RejectDriver
2949 Do not display functions compiled or elapsed time.
2967 Driver Var(report_times)
2970 Driver JoinedOrMissing
2973 Driver Joined Separate
2977 ; C option, but driver must not handle as "-u ndef".
2980 Common Driver Var(verbose_flag)
2981 Enable verbose output.
2984 Common Var(version_flag) RejectDriver
2985 Display the compiler's version.
2988 Common Var(inhibit_warnings)
2992 Driver Separate Var(wrapper_string)
2995 Driver Joined Separate
2998 Driver RejectNegative Negative(pie)
2999 Create a shared library.
3005 Driver Separate Alias(specs=)
3018 ; Documented for Fortran, but always accepted by driver.
3025 ; Documented for Go, but always accepted by driver.
3043 Driver RejectNegative Negative(shared)
3044 Don't create a position independent executable.
3047 Driver RejectNegative Negative(no-pie)
3048 Create a position independent executable.
3051 Driver Joined Separate
3054 Common Report Var(flag_ipa_ra) Optimization
3055 Use caller save register across calls if possible.
3057 ; This comment is to ensure we retain the blank line above.