1 ; Options for the C, ObjC, C++ and ObjC++ front ends.
2 ; Copyright (C) 2003-2017 Free Software Foundation, Inc.
4 ; This file is part of GCC.
6 ; GCC is free software; you can redistribute it and/or modify it under
7 ; the terms of the GNU General Public License as published by the Free
8 ; Software Foundation; either version 3, or (at your option) any later
11 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 ; You should have received a copy of the GNU General Public License
17 ; along with GCC; see the file COPYING3. If not see
18 ; <http://www.gnu.org/licenses/>.
20 ; See the GCC internals manual for a description of this file's format.
22 ; Please try to keep this file in ASCII collating order.
37 C ObjC C++ ObjC++ Warning Alias(Wall)
40 C ObjC C++ ObjC++ Alias(ansi)
43 C ObjC C++ ObjC++ Separate Alias(A) MissingArgError(assertion missing after %qs)
46 C ObjC C++ ObjC++ Joined Alias(A) MissingArgError(assertion missing after %qs)
49 C ObjC C++ ObjC++ Alias(C)
52 C ObjC C++ ObjC++ Alias(CC)
55 C ObjC C++ ObjC++ Separate Alias(D) MissingArgError(macro name missing after %qs)
58 C ObjC C++ ObjC++ Joined Alias(D) MissingArgError(macro name missing after %qs)
61 C ObjC C++ ObjC++ Alias(M)
64 C ObjC C++ ObjC++ Separate Alias(d)
67 C ObjC C++ ObjC++ Joined Alias(d)
70 C ObjC C++ ObjC++ Separate Alias(imacros) MissingArgError(missing filename after %qs)
73 C ObjC C++ ObjC++ Joined Alias(imacros) MissingArgError(missing filename after %qs)
76 C ObjC C++ ObjC++ Separate Alias(include) MissingArgError(missing filename after %qs)
79 C ObjC C++ ObjC++ Joined Alias(include) MissingArgError(missing filename after %qs)
82 C ObjC C++ ObjC++ Alias(I, -)
85 C ObjC C++ ObjC++ Separate Alias(I) MissingArgError(missing path after %qs)
88 C ObjC C++ ObjC++ Joined Alias(I) MissingArgError(missing path after %qs)
90 -include-directory-after
91 C ObjC C++ ObjC++ Separate Alias(idirafter) MissingArgError(missing path after %qs)
93 -include-directory-after=
94 C ObjC C++ ObjC++ Joined Alias(idirafter) MissingArgError(missing path after %qs)
97 C ObjC C++ ObjC++ Separate Alias(iprefix)
100 C ObjC C++ ObjC++ JoinedOrMissing Alias(iprefix)
103 C ObjC C++ ObjC++ Separate Alias(iwithprefix)
105 -include-with-prefix=
106 C ObjC C++ ObjC++ JoinedOrMissing Alias(iwithprefix)
108 -include-with-prefix-after
109 C ObjC C++ ObjC++ Separate Alias(iwithprefix)
111 -include-with-prefix-after=
112 C ObjC C++ ObjC++ JoinedOrMissing Alias(iwithprefix)
114 -include-with-prefix-before
115 C ObjC C++ ObjC++ Separate Alias(iwithprefixbefore)
117 -include-with-prefix-before=
118 C ObjC C++ ObjC++ JoinedOrMissing Alias(iwithprefixbefore)
121 Driver Alias(no-integrated-cpp)
124 C ObjC C++ ObjC++ Alias(P)
126 -no-standard-includes
127 C ObjC C++ ObjC++ Alias(nostdinc)
130 C ObjC C++ ObjC++ Alias(w)
133 C ObjC C++ ObjC++ Separate Alias(o)
136 C ObjC C++ ObjC++ Joined Alias(o)
139 C ObjC C++ ObjC++ Joined Separate
142 C ObjC C++ ObjC++ Alias(pedantic)
145 C ObjC C++ ObjC++ Undocumented Alias(E)
147 -print-missing-file-dependencies
148 C ObjC C++ ObjC++ Alias(MG)
151 C ObjC C++ ObjC++ Alias(H)
154 Driver Alias(traditional)
157 C ObjC C++ ObjC++ Alias(traditional-cpp)
160 C ObjC C++ ObjC++ Alias(trigraphs)
163 C ObjC C++ ObjC++ Separate Alias(U) MissingArgError(macro name missing after %qs)
166 C ObjC C++ ObjC++ Joined Alias(U) MissingArgError(macro name missing after %qs)
169 C ObjC C++ ObjC++ Alias(MM)
172 Common C ObjC C++ ObjC++ Alias(v)
175 C ObjC C++ ObjC++ NoDriverArg Separate Alias(MD) MissingArgError(missing filename after %qs)
177 -write-user-dependencies
178 C ObjC C++ ObjC++ NoDriverArg Separate Alias(MMD) MissingArgError(missing filename after %qs)
181 C ObjC C++ ObjC++ Joined Separate MissingArgError(assertion missing after %qs)
182 -A<question>=<answer> Assert the <answer> to <question>. Putting '-' before <question> disables the <answer> to <question>.
186 Do not discard comments.
190 Do not discard comments in macro expansions.
193 C ObjC C++ ObjC++ Joined Separate MissingArgError(macro name missing after %qs)
194 -D<macro>[=<val>] Define a <macro> with <val> as its value. If just <macro> is given, <val> is taken to be 1.
197 C ObjC C++ ObjC++ Undocumented Var(flag_preprocess_only)
200 Driver C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)
201 -F <dir> Add <dir> to the end of the main framework include path.
204 C Var(flag_gimple) Init(0)
205 Enable parsing GIMPLE.
209 Print the name of header files as they are used.
212 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)
213 -I <dir> Add <dir> to the end of the main include path.
217 Generate make dependencies.
220 C ObjC C++ ObjC++ NoDriverArg Separate MissingArgError(missing filename after %qs)
221 Generate make dependencies and compile.
224 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing filename after %qs)
225 -MF <file> Write dependency output to the given file.
229 Treat missing header files as generated files.
233 Like -M but ignore system header files.
236 C ObjC C++ ObjC++ NoDriverArg Separate MissingArgError(missing filename after %qs)
237 Like -MD but ignore system header files.
241 Generate phony targets for all headers.
244 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing makefile target after %qs)
245 -MQ <target> Add a MAKE-quoted target.
248 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing makefile target after %qs)
249 -MT <target> Add an unquoted target.
253 Do not generate #line directives.
256 C ObjC C++ ObjC++ Joined Separate MissingArgError(macro name missing after %qs)
257 -U<macro> Undefine <macro>.
260 C ObjC C++ ObjC++ LTO Var(warn_abi) Warning
261 Warn about things that will change when compiling with an ABI-compliant compiler.
264 C ObjC C++ ObjC++ LTO Joined RejectNegative UInteger Warning
265 Warn about things that change between the current -fabi-version and the specified version.
268 C++ ObjC++ Var(warn_abi_tag) Warning
269 Warn if a subobject has an abi_tag attribute that the complete object type does not have.
272 C ObjC C++ ObjC++ LTO Var(warn_psabi) Init(1) Warning Undocumented LangEnabledBy(C ObjC C++ ObjC++,Wabi)
275 C ObjC C++ ObjC++ Var(warn_address) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
276 Warn about suspicious uses of memory addresses.
279 Name(warn_aligned_new_level) Type(int) UnknownError(argument %qs to %<-Waligned-new%> not recognized)
282 Enum(warn_aligned_new_level) String(none) Value(0)
285 Enum(warn_aligned_new_level) String(global) Value(1)
288 Enum(warn_aligned_new_level) String(all) Value(2)
291 C++ ObjC++ Alias(Waligned-new=,global,none)
292 Warn about 'new' of type with extended alignment without -faligned-new.
295 C++ ObjC++ Var(warn_aligned_new) Enum(warn_aligned_new_level) Joined RejectNegative Warning LangEnabledBy(C++ ObjC++,Wall,1,0)
296 -Waligned-new=[none|global|all] Warn even if 'new' uses a class member allocation function.
299 C ObjC C++ ObjC++ Warning
300 Enable most warning messages.
303 C ObjC C++ ObjC++ Var(warn_alloca) Warning
304 Warn on any use of alloca.
306 Walloc-size-larger-than=
307 C ObjC C++ ObjC++ Var(warn_alloc_size_limit) Warning Joined LangEnabledBy(C ObjC C++ ObjC++,Wall)
308 -Walloc-size-larger-than=<bytes> Warn for calls to allocation functions that
309 attempt to allocate objects larger than the specified number of bytes.
312 C ObjC C++ ObjC++ Var(warn_alloc_zero) Warning
313 -Walloc-zero Warn for calls to allocation functions that specify zero bytes.
316 C ObjC C++ LTO ObjC++ Var(warn_alloca_limit) Warning Joined RejectNegative UInteger
317 -Walloca-larger-than=<number> Warn on unbounded uses of
318 alloca, and on bounded uses of alloca whose bound can be larger than
322 LangEnabledBy(C ObjC C++ ObjC++,Wall)
326 LangEnabledBy(C ObjC C++ ObjC++,Wall,1,0)
330 ObjC ObjC++ Var(warn_assign_intercept) Warning
331 Warn whenever an Objective-C assignment is being intercepted by the garbage collector.
334 C ObjC Var(warn_bad_function_cast) Warning
335 Warn about casting functions to incompatible types.
338 C ObjC C++ ObjC++ Var(warn_bool_compare) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
339 Warn about boolean expression compared with an integer value different from true/false.
342 C ObjC C++ ObjC++ Var(warn_bool_op) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
343 Warn about certain operations on boolean expressions.
346 C ObjC C++ ObjC++ Var(warn_frame_address) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
347 Warn when __builtin_frame_address or __builtin_return_address is used unsafely.
349 Wbuiltin-declaration-mismatch
350 C ObjC C++ ObjC++ Var(warn_builtin_declaraion_mismatch) Init(1) Warning
351 Warn when a built-in function is declared with the wrong signature.
353 Wbuiltin-macro-redefined
354 C ObjC C++ ObjC++ CPP(warn_builtin_macro_redefined) CppReason(CPP_W_BUILTIN_MACRO_REDEFINED) Var(cpp_warn_builtin_macro_redefined) Init(1) Warning
355 Warn when a built-in preprocessor macro is undefined or redefined.
358 C ObjC CPP(cpp_warn_c90_c99_compat) CppReason(CPP_W_C90_C99_COMPAT) Var(warn_c90_c99_compat) Init(-1) Warning
359 Warn about features not present in ISO C90, but present in ISO C99.
362 C ObjC Var(warn_c99_c11_compat) Init(-1) Warning
363 Warn about features not present in ISO C99, but present in ISO C11.
366 C ObjC Var(warn_cxx_compat) CPP(warn_cxx_operator_names) CppReason(CPP_W_CXX_OPERATOR_NAMES) Init(0) Warning
367 Warn about C constructs that are not in the common subset of C and C++.
370 C++ ObjC++ Warning Alias(Wc++11-compat) Undocumented
373 C++ ObjC++ Var(warn_cxx11_compat) Warning LangEnabledBy(C++ ObjC++,Wall) Init(0) CPP(cpp_warn_cxx11_compat) CppReason(CPP_W_CXX11_COMPAT)
374 Warn about C++ constructs whose meaning differs between ISO C++ 1998 and ISO C++ 2011.
377 C++ ObjC++ Var(warn_cxx14_compat) Warning LangEnabledBy(C++ ObjC++,Wall)
378 Warn about C++ constructs whose meaning differs between ISO C++ 2011 and ISO C++ 2014.
381 C++ ObjC++ Warning Alias(Wc++17-compat) Undocumented
384 C++ ObjC++ Var(warn_cxx17_compat) Warning LangEnabledBy(C++ ObjC++,Wall)
385 Warn about C++ constructs whose meaning differs between ISO C++ 2014 and ISO C++ 2017.
388 C ObjC C++ ObjC++ Var(warn_cast_qual) Warning
389 Warn about casts which discard qualifiers.
392 C++ ObjC++ Warning Alias(Wcatch-value=, 1, 0)
393 Warn about catch handlers of non-reference type.
396 C++ ObjC++ Var(warn_catch_value) Warning Joined RejectNegative UInteger LangEnabledBy(C++ ObjC++,Wall, 1, 0)
397 Warn about catch handlers of non-reference type.
400 C ObjC C++ ObjC++ Var(warn_char_subscripts) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
401 Warn about subscripts whose type is \"char\".
404 C ObjC C++ ObjC++ Var(warn_chkp) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
405 Warn about memory access errors found by Pointer Bounds Checker.
408 C ObjC C++ ObjC++ Var(warn_clobbered) Warning EnabledBy(Wextra)
409 Warn about variables that might be changed by \"longjmp\" or \"vfork\".
412 C ObjC C++ ObjC++ CPP(warn_comments) CppReason(CPP_W_COMMENTS) Var(cpp_warn_comment) Init(0) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
413 Warn about possibly nested block comments, and C++ comments spanning more than one physical line.
416 C ObjC C++ ObjC++ Warning Alias(Wcomment)
417 Synonym for -Wcomment.
419 Wconditionally-supported
420 C++ ObjC++ Var(warn_conditionally_supported) Warning
421 Warn for conditionally-supported constructs.
424 C ObjC C++ ObjC++ Var(warn_conversion) Warning
425 Warn for implicit type conversions that may change a value.
428 C++ ObjC++ Var(warn_conversion_null) Init(1) Warning
429 Warn for converting NULL from/to a non-pointer type.
432 C ObjC C++ ObjC++ CppReason(CPP_W_WARNING_DIRECTIVE)
433 ; Documented in common.opt
436 C++ ObjC++ Var(warn_ctor_dtor_privacy) Warning
437 Warn when all constructors and destructors are private.
440 C ObjC C++ ObjC++ Var(warn_dangling_else) Warning LangEnabledBy(C ObjC C++ ObjC++,Wparentheses)
441 Warn about dangling else.
444 C ObjC C++ ObjC++ CPP(warn_date_time) CppReason(CPP_W_DATE_TIME) Var(cpp_warn_date_time) Init(0) Warning
445 Warn about __TIME__, __DATE__ and __TIMESTAMP__ usage.
447 Wdeclaration-after-statement
448 C ObjC Var(warn_declaration_after_statement) Init(-1) Warning
449 Warn when a declaration is found after a statement.
452 C++ ObjC++ Var(warn_delete_incomplete) Init(1) Warning
453 Warn when deleting a pointer to incomplete type.
455 Wdelete-non-virtual-dtor
456 C++ ObjC++ Var(warn_delnonvdtor) Warning LangEnabledBy(C++ ObjC++,Wall || Weffc++)
457 Warn about deleting polymorphic objects with non-virtual destructors.
460 C C++ ObjC ObjC++ CPP(cpp_warn_deprecated) CppReason(CPP_W_DEPRECATED) Var(warn_deprecated) Init(1) Warning
461 Warn if a deprecated compiler feature, class, method, or field is used.
464 C ObjC Var(warn_designated_init) Init(1) Warning
465 Warn about positional initialization of structs requiring designated initializers.
467 Wdiscarded-array-qualifiers
468 C ObjC Var(warn_discarded_array_qualifiers) Init(1) Warning
469 Warn if qualifiers on arrays which are pointer targets are discarded.
471 Wdiscarded-qualifiers
472 C ObjC Var(warn_discarded_qualifiers) Init(1) Warning
473 Warn if type qualifiers on pointers are discarded.
476 C ObjC C++ ObjC++ Var(warn_div_by_zero) Init(1) Warning
477 Warn about compile-time integer division by zero.
480 C ObjC C++ ObjC++ Var(warn_duplicated_branches) Init(0) Warning
481 Warn about duplicated branches in if-else statements.
484 C ObjC C++ ObjC++ Var(warn_duplicated_cond) Init(0) Warning
485 Warn about duplicated conditions in an if-else-if chain.
488 C++ ObjC++ Var(warn_ecpp) Warning
489 Warn about violations of Effective C++ style rules.
492 C ObjC C++ ObjC++ Var(warn_empty_body) Warning EnabledBy(Wextra)
493 Warn about an empty body in an if or else statement.
496 C ObjC C++ ObjC++ CPP(warn_endif_labels) CppReason(CPP_W_ENDIF_LABELS) Var(cpp_warn_endif_labels) Init(1) Warning LangEnabledBy(C ObjC C++ ObjC++,Wpedantic)
497 Warn about stray tokens after #else and #endif.
500 C ObjC C++ ObjC++ Var(warn_enum_compare) Init(-1) Warning LangEnabledBy(C ObjC,Wall || Wc++-compat)
501 Warn about comparison of different enum types.
505 ; Documented in common.opt
507 Werror-implicit-function-declaration
508 C ObjC RejectNegative Warning Alias(Werror=, implicit-function-declaration)
509 This switch is deprecated; use -Werror=implicit-function-declaration instead.
512 C ObjC C++ ObjC++ Warning
516 C++ ObjC++ Var(warn_extra_semi) Warning
517 Warn about semicolon after in-class function definition.
520 C ObjC C++ ObjC++ Var(warn_float_conversion) Warning LangEnabledBy(C ObjC C++ ObjC++,Wconversion)
521 Warn for implicit type conversions that cause loss of floating point precision.
524 C ObjC C++ ObjC++ Var(warn_float_equal) Warning
525 Warn if testing floating point numbers for equality.
528 C ObjC C++ ObjC++ Warning Alias(Wformat=, 1, 0)
529 Warn about printf/scanf/strftime/strfmon format string anomalies.
532 C ObjC C++ ObjC++ Var(warn_format_contains_nul) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 1, 0)
533 Warn about format strings that contain NUL bytes.
536 C ObjC C++ ObjC++ Var(warn_format_extra_args) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 1, 0)
537 Warn if passing too many arguments to a function for its format string.
540 C ObjC C++ ObjC++ Var(warn_format_nonliteral) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 2, 0)
541 Warn about format strings that are not literals.
544 C ObjC C++ LTO ObjC++ Warning Alias(Wformat-overflow=, 1, 0) IntegerRange(0, 2)
545 Warn about function calls with format strings that write past the end
546 of the destination region. Same as -Wformat-overflow=1.
549 C ObjC C++ ObjC++ Var(warn_format_security) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 2, 0)
550 Warn about possible security problems with format functions.
553 C ObjC C++ ObjC++ Var(warn_format_signedness) Warning
554 Warn about sign differences with format functions.
557 C ObjC C++ LTO ObjC++ Warning Alias(Wformat-truncation=, 1, 0)
558 Warn about calls to snprintf and similar functions that truncate output.
559 Same as -Wformat-truncation=1.
562 C ObjC C++ ObjC++ Var(warn_format_y2k) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=,warn_format >= 2, 0)
563 Warn about strftime formats yielding 2-digit years.
566 C ObjC C++ ObjC++ Var(warn_format_zero_length) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=,warn_format >= 1, 0)
567 Warn about zero-length formats.
570 C ObjC C++ ObjC++ Joined RejectNegative UInteger Var(warn_format) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall, 1, 0) IntegerRange(0, 2)
571 Warn about printf/scanf/strftime/strfmon format string anomalies.
574 C ObjC C++ LTO ObjC++ Joined RejectNegative UInteger Var(warn_format_overflow) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 1, 0) IntegerRange(0, 2)
575 Warn about function calls with format strings that write past the end
576 of the destination region.
579 C ObjC C++ ObjC++ Joined RejectNegative UInteger Var(warn_format_trunc) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 1, 0) IntegerRange(0, 2)
580 Warn about calls to snprintf and similar functions that truncate output.
583 C ObjC C++ ObjC++ Var(warn_if_not_aligned) Init(1) Warning
584 Warn when the field in a struct is not aligned.
587 C C++ Var(warn_ignored_qualifiers) Warning EnabledBy(Wextra)
588 Warn whenever type qualifiers are ignored.
591 C C++ Var(warn_ignored_attributes) Init(1) Warning
592 Warn whenever attributes are ignored.
594 Wincompatible-pointer-types
595 C ObjC Var(warn_incompatible_pointer_types) Init(1) Warning
596 Warn when there is a conversion between pointers that have incompatible types.
599 C ObjC C++ ObjC++ Var(warn_init_self) Warning LangEnabledBy(C++ ObjC++,Wall)
600 Warn about variables which are initialized to themselves.
603 C ObjC Var(warn_implicit) Warning LangEnabledBy(C ObjC,Wall)
604 Warn about implicit declarations.
606 Wimplicit-fallthrough=
607 LangEnabledBy(C ObjC C++ ObjC++,Wextra,3,0)
611 C ObjC C++ ObjC++ Var(warn_double_promotion) Warning
612 Warn about implicit conversions from \"float\" to \"double\".
614 Wexpansion-to-defined
615 C ObjC C++ ObjC++ CPP(warn_expansion_to_defined) CppReason(CPP_W_EXPANSION_TO_DEFINED) Var(cpp_warn_expansion_to_defined) Init(0) Warning EnabledBy(Wextra || Wpedantic)
616 Warn if \"defined\" is used outside #if.
618 Wimplicit-function-declaration
619 C ObjC Var(warn_implicit_function_declaration) Init(-1) Warning LangEnabledBy(C ObjC,Wimplicit)
620 Warn about implicit function declarations.
623 C ObjC Var(warn_implicit_int) Init(-1) Warning LangEnabledBy(C ObjC,Wimplicit)
624 Warn when a declaration does not specify a type.
627 C ObjC C++ ObjC++ Undocumented Ignore
629 Winherited-variadic-ctor
630 C++ ObjC++ Var(warn_inh_var_ctor) Init(1) Warning
631 Warn about C++11 inheriting constructors when the base has a variadic constructor.
634 C ObjC Var(warn_int_conversion) Init(1) Warning
635 Warn about incompatible integer to pointer and pointer to integer conversions.
638 C ObjC C++ ObjC++ Var(warn_int_in_bool_context) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
639 Warn for suspicious integer expressions in boolean context.
642 C ObjC C++ ObjC++ Var(warn_int_to_pointer_cast) Init(1) Warning
643 Warn when there is a cast to a pointer from an integer of a different size.
646 C++ ObjC++ Var(warn_invalid_offsetof) Init(1) Warning
647 Warn about invalid uses of the \"offsetof\" macro.
650 C ObjC C++ ObjC++ CPP(warn_invalid_pch) CppReason(CPP_W_INVALID_PCH) Var(cpp_warn_invalid_pch) Init(0) Warning
651 Warn about PCH files that are found but not used.
654 C ObjC Var(warn_jump_misses_init) Warning LangEnabledby(C ObjC,Wc++-compat)
655 Warn when a jump misses a variable initialization.
658 C++ ObjC++ CPP(warn_literal_suffix) CppReason(CPP_W_LITERAL_SUFFIX) Var(cpp_warn_literal_suffix) Init(1) Warning
659 Warn when a string or character literal is followed by a ud-suffix which does not begin with an underscore.
662 C ObjC C++ ObjC++ Var(warn_logical_op) Init(0) Warning
663 Warn when a logical operator is suspiciously always evaluating to true or false.
665 Wlogical-not-parentheses
666 C ObjC C++ ObjC++ Var(warn_logical_not_paren) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
667 Warn when logical not is used on the left hand side operand of a comparison.
670 C ObjC C++ ObjC++ CPP(cpp_warn_long_long) CppReason(CPP_W_LONG_LONG) Var(warn_long_long) Init(-1) Warning LangEnabledBy(C ObjC,Wc90-c99-compat)
671 Do not warn about using \"long long\" when -pedantic.
674 C ObjC C++ ObjC++ Var(warn_main) Init(-1) Warning LangEnabledBy(C ObjC,Wall, 2, 0)
675 Warn about suspicious declarations of \"main\".
678 LangEnabledBy(C ObjC C++ ObjC++,Wpedantic, 2, 0)
681 Wmemset-transposed-args
682 C ObjC C++ ObjC++ Var(warn_memset_transposed_args) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
683 Warn about suspicious calls to memset where the third argument is constant literal zero and the second is not.
686 C ObjC C++ ObjC++ Var(warn_memset_elt_size) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
687 Warn about suspicious calls to memset where the third argument contains the number of elements not multiplied by the element size.
689 Wmisleading-indentation
690 C C++ Common Var(warn_misleading_indentation) Warning LangEnabledBy(C C++,Wall)
691 Warn when the indentation of the code does not reflect the block structure.
694 C ObjC C++ ObjC++ Var(warn_missing_braces) Warning LangEnabledBy(C ObjC,Wall)
695 Warn about possibly missing braces around initializers.
697 Wmissing-declarations
698 C ObjC C++ ObjC++ Var(warn_missing_declarations) Warning
699 Warn about global functions without previous declarations.
701 Wmissing-field-initializers
702 C ObjC C++ ObjC++ Var(warn_missing_field_initializers) Warning EnabledBy(Wextra)
703 Warn about missing fields in struct initializers.
705 Wmultistatement-macros
706 C ObjC C++ ObjC++ Var(warn_multistatement_macros) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
707 Warn about unsafe macros expanding to multiple statements used as a body of a clause such as if, else, while, switch, or for.
709 Wmultiple-inheritance
710 C++ ObjC++ Var(warn_multiple_inheritance) Warning
711 Warn on direct multiple inheritance.
714 C++ ObjC++ Var(warn_namespaces) Warning
715 Warn on namespace definition.
718 C ObjC C++ ObjC++ Var(warn_packed_not_aligned) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
719 Warn when fields in a struct with the packed attribute are misaligned.
722 C++ ObjC++ Var(warn_sized_deallocation) Warning EnabledBy(Wextra)
723 Warn about missing sized deallocation functions.
726 C ObjC C++ ObjC++ Var(warn_sizeof_pointer_div) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
727 Warn about suspicious divisions of two sizeof expressions that don't work correctly with pointers.
729 Wsizeof-pointer-memaccess
730 C ObjC C++ ObjC++ Var(warn_sizeof_pointer_memaccess) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
731 Warn about suspicious length parameters to certain string functions if the argument uses sizeof.
733 Wsizeof-array-argument
734 C ObjC C++ ObjC++ Var(warn_sizeof_array_argument) Warning Init(1)
735 Warn when sizeof is applied on a parameter declared as an array.
738 C ObjC C++ ObjC++ Warning Alias(Wstringop-overflow=, 2, 0)
739 Warn about buffer overflow in string manipulation functions like memcpy
743 C ObjC C++ ObjC++ Joined RejectNegative UInteger Var(warn_stringop_overflow) Init(2) Warning LangEnabledBy(C ObjC C++ ObjC++, Wall, 2, 0) IntegerRange(0, 4)
744 Under the control of Object Size type, warn about buffer overflow in string
745 manipulation functions like memcpy and strcpy.
747 Wsuggest-attribute=format
748 C ObjC C++ ObjC++ Var(warn_suggest_attribute_format) Warning
749 Warn about functions which might be candidates for format attributes.
752 C++ ObjC++ Var(warn_override) Warning
753 Suggest that the override keyword be used when the declaration of a virtual
754 function overrides another.
757 C ObjC C++ ObjC++ Var(warn_switch) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
758 Warn about enumerated switches, with no default, missing a case.
761 C ObjC C++ ObjC++ Var(warn_switch_default) Warning
762 Warn about enumerated switches missing a \"default:\" statement.
765 C ObjC C++ ObjC++ Var(warn_switch_enum) Warning
766 Warn about all enumerated switches missing a specific case.
769 C ObjC C++ ObjC++ Var(warn_switch_bool) Warning Init(1)
770 Warn about switches with boolean controlling expression.
773 C++ ObjC++ Var(warn_templates) Warning
774 Warn on primary template declaration.
776 Wmissing-format-attribute
777 C ObjC C++ ObjC++ Warning Alias(Wsuggest-attribute=format)
780 Wmissing-include-dirs
781 C ObjC C++ ObjC++ CPP(warn_missing_include_dirs) CppReason(CPP_W_MISSING_INCLUDE_DIRS) Var(cpp_warn_missing_include_dirs) Init(0) Warning
782 Warn about user-specified include directories that do not exist.
784 Wmissing-parameter-type
785 C ObjC Var(warn_missing_parameter_type) Warning EnabledBy(Wextra)
786 Warn about function parameters declared without a type specifier in K&R-style functions.
789 C ObjC Var(warn_missing_prototypes) Warning
790 Warn about global functions without prototypes.
793 C ObjC C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
796 C ObjC C++ ObjC++ CPP(warn_multichar) CppReason(CPP_W_MULTICHAR) Var(cpp_warn_multichar) Init(0) Warning
797 Warn about use of multi-character character constants.
800 C ObjC C++ ObjC++ Warning Var(warn_narrowing) Init(-1) LangEnabledBy(C++ ObjC++,Wall || Wc++11-compat)
801 Warn about narrowing conversions within { } that are ill-formed in C++11.
804 C ObjC Var(warn_nested_externs) Warning
805 Warn about \"extern\" declarations not at file scope.
808 C++ ObjC++ Var(warn_noexcept) Warning
809 Warn when a noexcept expression evaluates to false even though the expression can't actually throw.
812 C++ ObjC++ Warning Var(warn_noexcept_type) LangEnabledBy(C++ ObjC++,Wabi || Wc++17-compat)
813 Warn if C++17 noexcept function type will change the mangled name of a symbol.
816 C++ ObjC++ Var(warn_nontemplate_friend) Init(1) Warning
817 Warn when non-templatized friend functions are declared within a template.
820 C++ ObjC++ Var(warn_class_memaccess) Warning LangEnabledBy(C++ ObjC++, Wall)
821 Warn for unsafe raw memory writes to objects of class types.
824 C++ ObjC++ Var(warn_nonvdtor) Warning LangEnabledBy(C++ ObjC++,Weffc++)
825 Warn about non-virtual destructors.
828 C ObjC C++ ObjC++ Var(warn_nonnull) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=,warn_format >= 1,0)
829 Warn about NULL being passed to argument slots marked as requiring non-NULL.
832 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
836 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
840 C ObjC C++ ObjC++ Warning Alias(Wnormalized=,nfc,none)
844 C ObjC C++ ObjC++ RejectNegative Joined Warning CPP(warn_normalize) CppReason(CPP_W_NORMALIZE) Init(normalized_C) Var(cpp_warn_normalize) Enum(cpp_normalize_level)
845 -Wnormalized=[none|id|nfc|nfkc] Warn about non-normalized Unicode strings.
847 ; Required for these enum values.
852 Name(cpp_normalize_level) Type(int) UnknownError(argument %qs to %<-Wnormalized%> not recognized)
855 Enum(cpp_normalize_level) String(none) Value(normalized_none)
858 Enum(cpp_normalize_level) String(nfkc) Value(normalized_KC)
861 Enum(cpp_normalize_level) String(id) Value(normalized_identifier_C)
864 Enum(cpp_normalize_level) String(nfc) Value(normalized_C)
867 C++ ObjC++ Var(warn_old_style_cast) Warning
868 Warn if a C-style cast is used in a program.
870 Wold-style-declaration
871 C ObjC Var(warn_old_style_declaration) Warning EnabledBy(Wextra)
872 Warn for obsolescent usage in a declaration.
874 Wold-style-definition
875 C ObjC Var(warn_old_style_definition) Warning
876 Warn if an old-style parameter definition is used.
879 C C++ Var(warn_openmp_simd) Warning LangEnabledBy(C C++,Wall)
880 Warn if a simd directive is overridden by the vectorizer cost model.
883 C ObjC C++ ObjC++ Var(warn_overlength_strings) Warning LangEnabledBy(C ObjC C++ ObjC++,Wpedantic)
884 Warn if a string is longer than the maximum portable length specified by the standard.
887 C++ ObjC++ Var(warn_overloaded_virtual) Warning
888 Warn about overloaded virtual function names.
891 C ObjC Var(warn_override_init) Warning EnabledBy(Wextra)
892 Warn about overriding initializers without side effects.
894 Woverride-init-side-effects
895 C ObjC Var(warn_override_init_side_effects) Init(1) Warning
896 Warn about overriding initializers with side effects.
898 Wpacked-bitfield-compat
899 C ObjC C++ ObjC++ Var(warn_packed_bitfield_compat) Init(-1) Warning
900 Warn about packed bit-fields whose offset changed in GCC 4.4.
903 C ObjC C++ ObjC++ Var(warn_parentheses) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
904 Warn about possibly missing parentheses.
907 C ObjC C++ ObjC++ CPP(cpp_pedantic) CppReason(CPP_W_PEDANTIC) Warning
908 ; Documented in common.opt
911 C++ ObjC++ Var(warn_pmf2ptr) Init(1) Warning
912 Warn when converting the type of pointers to member functions.
915 C ObjC C++ ObjC++ Var(warn_pointer_arith) Warning LangEnabledBy(C ObjC C++ ObjC++,Wpedantic)
916 Warn about function pointer arithmetic.
919 C ObjC Var(warn_pointer_sign) Warning LangEnabledBy(C ObjC,Wall || Wpedantic)
920 Warn when a pointer differs in signedness in an assignment.
923 C ObjC C++ ObjC++ Var(warn_pointer_compare) Init(1) Warning
924 Warn when a pointer is compared with a zero character constant.
927 C ObjC Var(warn_pointer_to_int_cast) Init(1) Warning
928 Warn when a pointer is cast to an integer of a different size.
931 C ObjC C++ ObjC++ Var(warn_pragmas) Init(1) Warning
932 Warn about misuses of pragmas.
934 Wproperty-assign-default
935 ObjC ObjC++ Var(warn_property_assign_default) Init(1) Warning
936 Warn if a property for an Objective-C object has no assign semantics specified.
939 ObjC ObjC++ Var(warn_protocol) Init(1) Warning
940 Warn if inherited methods are unimplemented.
943 C++ Warning Alias(Wplacement-new=, 1, 0)
944 Warn for placement new expressions with undefined behavior.
947 C++ Joined RejectNegative UInteger Var(warn_placement_new) Init(-1) Warning IntegerRange(0, 2)
948 Warn for placement new expressions with undefined behavior.
951 C ObjC C++ ObjC++ Var(warn_redundant_decls) Warning
952 Warn about multiple declarations of the same object.
955 C++ ObjC++ Var(warn_register) Warning
956 Warn about uses of register storage specifier.
959 C++ ObjC++ Var(warn_reorder) Warning LangEnabledBy(C++ ObjC++,Wall)
960 Warn when the compiler reorders code.
963 C ObjC C++ ObjC++ Var(warn_return_type) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
964 Warn whenever a function's return type defaults to \"int\" (C), or about inconsistent return types (C++).
966 Wscalar-storage-order
967 C ObjC C++ ObjC++ Init(1) Warning
968 Warn on suspicious constructs involving reverse scalar storage order.
971 ObjC ObjC++ Var(warn_selector) Warning
972 Warn if a selector has multiple methods.
975 C ObjC C++ ObjC++ Var(warn_sequence_point) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
976 Warn about possible violations of sequence point rules.
979 ObjC ObjC++ Var(warn_shadow_ivar) EnabledBy(Wshadow) Init(1) Warning
980 Warn if a local declaration hides an instance variable.
983 C ObjC C++ ObjC++ Warning Alias(Wshift-overflow=, 1, 0)
984 Warn if left shift of a signed value overflows.
987 C ObjC C++ ObjC++ Joined RejectNegative UInteger Var(warn_shift_overflow) Init(-1) Warning IntegerRange(0, 2)
988 Warn if left shift of a signed value overflows.
990 Wshift-count-negative
991 C ObjC C++ ObjC++ Var(warn_shift_count_negative) Init(1) Warning
992 Warn if shift count is negative.
994 Wshift-count-overflow
995 C ObjC C++ ObjC++ Var(warn_shift_count_overflow) Init(1) Warning
996 Warn if shift count >= width of type.
998 Wshift-negative-value
999 C ObjC C++ ObjC++ Var(warn_shift_negative_value) Init(-1) Warning
1000 Warn if left shifting a negative value.
1003 C ObjC C++ ObjC++ Var(warn_sign_compare) Warning LangEnabledBy(C++ ObjC++,Wall)
1004 Warn about signed-unsigned comparisons.
1007 C ObjC C++ ObjC++ EnabledBy(Wextra)
1011 C ObjC C++ ObjC++ Var(warn_sign_conversion) Warning LangEnabledBy(C ObjC,Wconversion)
1012 Warn for implicit type conversions between signed and unsigned integers.
1015 C++ ObjC++ Var(warn_sign_promo) Warning
1016 Warn when overload promotes from unsigned to signed.
1018 Wstrict-null-sentinel
1019 C++ ObjC++ Warning Var(warn_strict_null_sentinel)
1020 Warn about uncasted NULL used as sentinel.
1023 C ObjC Var(warn_strict_prototypes) Warning
1024 Warn about unprototyped function declarations.
1027 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall, 3, 0) IntegerRange(0, 3)
1031 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall, 1, 0) IntegerRange(0, 5)
1034 Wstrict-selector-match
1035 ObjC ObjC++ Var(warn_strict_selector_match) Warning
1036 Warn if type signatures of candidate methods do not match exactly.
1039 C C++ Var(warn_sync_nand) Init(1) Warning
1040 Warn when __sync_fetch_and_nand and __sync_nand_and_fetch built-in functions are used.
1043 C++ ObjC++ Var(warn_synth) Warning
1044 Deprecated. This switch has no effect.
1047 C ObjC C++ ObjC++ Warning
1048 ; Documented in common.opt
1050 Wtautological-compare
1051 C ObjC C++ ObjC++ Var(warn_tautological_compare) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
1052 Warn if a comparison always evaluates to true or false.
1055 C++ ObjC++ Warning Var(warn_terminate) Init(1)
1056 Warn if a throw expression will always result in a call to terminate().
1059 C ObjC CPP(cpp_warn_traditional) CppReason(CPP_W_TRADITIONAL) Var(warn_traditional) Init(0) Warning
1060 Warn about features not present in traditional C.
1062 Wtraditional-conversion
1063 C ObjC Var(warn_traditional_conversion) Warning
1064 Warn of prototypes causing type conversions different from what would happen in the absence of prototype.
1067 C ObjC C++ ObjC++ CPP(warn_trigraphs) CppReason(CPP_W_TRIGRAPHS) Var(cpp_warn_trigraphs) Init(2) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
1068 Warn if trigraphs are encountered that might affect the meaning of the program.
1070 Wundeclared-selector
1071 ObjC ObjC++ Var(warn_undeclared_selector) Warning
1072 Warn about @selector()s without previously declared methods.
1075 C ObjC C++ ObjC++ CPP(warn_undef) CppReason(CPP_W_UNDEF) Var(cpp_warn_undef) Init(0) Warning
1076 Warn if an undefined macro is used in an #if directive.
1079 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
1082 Wmaybe-uninitialized
1083 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
1087 C ObjC C++ ObjC++ Warning Var(warn_unknown_pragmas) LangEnabledBy(C ObjC C++ ObjC++,Wall, 1, 0)
1088 Warn about unrecognized pragmas.
1090 Wunsuffixed-float-constants
1091 C ObjC Var(warn_unsuffixed_float_constants) Warning
1092 Warn about unsuffixed float constants.
1095 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
1096 ; documented in common.opt
1098 Wunused-local-typedefs
1099 C ObjC C++ ObjC++ Var(warn_unused_local_typedefs) Warning EnabledBy(Wunused)
1100 Warn when typedefs locally defined in a function are not used.
1103 C ObjC C++ ObjC++ CppReason(CPP_W_UNUSED_MACROS) Var(cpp_warn_unused_macros) Warning
1104 Warn about macros defined in the main file that are not used.
1107 C ObjC C++ ObjC++ Var(warn_unused_result) Init(1) Warning
1108 Warn if a caller of a function, marked with attribute warn_unused_result, does not use its return value.
1111 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wunused)
1112 ; documented in common.opt
1114 Wunused-const-variable
1115 C ObjC C++ ObjC++ Warning Alias(Wunused-const-variable=, 2, 0)
1116 Warn when a const variable is unused.
1118 Wunused-const-variable=
1119 C ObjC C++ ObjC++ Joined RejectNegative UInteger Var(warn_unused_const_variable) Warning LangEnabledBy(C ObjC,Wunused-variable, 1, 0) IntegerRange(0, 2)
1120 Warn when a const variable is unused.
1123 C ObjC C++ ObjC++ CPP(warn_variadic_macros) CppReason(CPP_W_VARIADIC_MACROS) Var(cpp_warn_variadic_macros) Init(0) Warning LangEnabledBy(C ObjC C++ ObjC++,Wpedantic || Wtraditional)
1124 Warn about using variadic macros.
1127 C ObjC C++ ObjC++ Warning Var(warn_varargs) Init(1)
1128 Warn about questionable usage of the macros used to retrieve variable arguments.
1131 C ObjC C++ ObjC++ Var(warn_vla) Init(-1) Warning
1132 Warn if a variable length array is used.
1135 C ObjC C++ ObjC++ Var(warn_vla_limit) Warning Joined RejectNegative UInteger
1136 -Wvla-larger-than=<number> Warn on unbounded uses of variable-length arrays, and
1137 on bounded uses of variable-length arrays whose bound can be
1138 larger than <number> bytes.
1140 Wvolatile-register-var
1141 C ObjC C++ ObjC++ Var(warn_volatile_register_var) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
1142 Warn when a register variable is declared volatile.
1144 Wvirtual-inheritance
1145 C++ ObjC++ Var(warn_virtual_inheritance) Warning
1146 Warn on direct virtual inheritance.
1148 Wvirtual-move-assign
1149 C++ ObjC++ Var(warn_virtual_move_assign) Warning Init(1)
1150 Warn if a virtual base has a non-trivial move assignment operator.
1153 C ObjC C++ ObjC++ Var(warn_write_strings) Warning
1154 In C++, nonzero means warn about deprecated conversion from string literals to 'char *'. In C, similar warning, except that the conversion is of course not deprecated by the ISO C standard.
1156 Wzero-as-null-pointer-constant
1157 C++ ObjC++ Var(warn_zero_as_null_pointer_constant) Warning
1158 Warn when a literal '0' is used as null pointer.
1161 C++ ObjC++ Var(warn_useless_cast) Warning
1162 Warn about useless casts.
1165 C++ ObjC++ Var(warn_subobject_linkage) Warning Init(1)
1166 Warn if a class type has a base or a field whose type uses the anonymous namespace or depends on a type with no linkage.
1168 Wduplicate-decl-specifier
1169 C ObjC Var(warn_duplicate_decl_specifier) Warning LangEnabledBy(C ObjC,Wall)
1170 Warn when a declaration has duplicate const, volatile, restrict or _Atomic specifier.
1173 C ObjC C++ ObjC++ Var(warn_restrict) Warning LangEnabledBy(C ObjC C++ ObjC++)
1174 Warn when an argument passed to a restrict-qualified parameter aliases with
1179 A synonym for -std=c89 (for C) or -std=c++98 (for C++).
1182 C ObjC C++ ObjC++ Joined
1183 ; Documented in common.opt. FIXME - what about -dI, -dD, -dN and -dD?
1185 fabi-compat-version=
1186 C++ ObjC++ Joined RejectNegative UInteger Var(flag_abi_compat_version) Init(-1)
1187 The version of the C++ ABI used for -Wabi warnings and link compatibility aliases.
1190 C++ ObjC++ Var(flag_access_control) Init(1)
1191 Enforce class member access control semantics.
1194 C ObjC C++ ObjC++ RejectNegative Joined Var(ada_specs_parent)
1195 -fada-spec-parent=unit Dump Ada specs as child units of given parent.
1198 C++ ObjC++ Alias(faligned-new=,1,0)
1199 Support C++17 allocation of over-aligned types.
1202 C++ ObjC++ Joined RejectNegative Var(aligned_new_threshold) UInteger Init(-1)
1203 -faligned-new=<N> Use C++17 over-aligned type allocation for alignments greater than N.
1206 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1208 fallow-parameterless-variadic-functions
1209 C ObjC Var(flag_allow_parameterless_variadic_functions)
1210 Allow variadic functions without named parameter.
1212 falt-external-templates
1213 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1214 No longer supported.
1217 C ObjC C++ ObjC++ Var(flag_no_asm, 0)
1218 Recognize the \"asm\" keyword.
1220 ; Define extra predefined macros for use in libgcc.
1222 C ObjC C++ ObjC++ Undocumented Var(flag_building_libgcc)
1225 C ObjC C++ ObjC++ Var(flag_no_builtin, 0)
1226 Recognize built-in functions.
1229 C ObjC C++ ObjC++ Joined
1231 fcanonical-system-headers
1233 Where shorter, use canonicalized paths to systems headers.
1235 fcheck-pointer-bounds
1236 C ObjC C++ ObjC++ LTO Report Var(flag_check_pointer_bounds)
1237 Add Pointer Bounds Checker instrumentation. fchkp-* flags are used to
1238 control instrumentation. Currently available for C, C++ and ObjC.
1240 fchkp-check-incomplete-type
1241 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_incomplete_type) Init(1)
1242 Generate pointer bounds checks for variables with incomplete type.
1244 fchkp-zero-input-bounds-for-main
1245 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_zero_input_bounds_for_main) Init(0)
1246 Use zero bounds for all incoming arguments in 'main' function. It helps when
1247 instrumented binaries are used with legacy libs.
1249 fchkp-first-field-has-own-bounds
1250 C ObjC C++ ObjC++ LTO RejectNegative Report Var(flag_chkp_first_field_has_own_bounds)
1251 Forces Pointer Bounds Checker to use narrowed bounds for address of the first
1252 field in the structure. By default pointer to the first field has the same
1253 bounds as pointer to the whole structure.
1256 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_narrow_bounds) Init(1)
1257 Control how Pointer Bounds Checker handle pointers to object fields. When
1258 narrowing is on, field bounds are used. Otherwise full object bounds are used.
1260 fchkp-narrow-to-innermost-array
1261 C ObjC C++ ObjC++ LTO RejectNegative Report Var(flag_chkp_narrow_to_innermost_arrray)
1262 Forces Pointer Bounds Checker to use bounds of the innermost arrays in case of
1263 nested static arrays access. By default outermost array is used.
1265 fchkp-flexible-struct-trailing-arrays
1266 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_flexible_struct_trailing_arrays)
1267 Forces Pointer Bounds Checker to treat all trailing arrays in structures as
1268 possibly flexible. By default only arrays fields with zero length or that are
1269 marked with attribute bnd_variable_size are treated as flexible.
1272 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_optimize) Init(-1)
1273 Allow Pointer Bounds Checker optimizations. By default allowed
1274 on optimization levels >0.
1276 fchkp-use-fast-string-functions
1277 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_use_fast_string_functions) Init(0)
1278 Allow to use *_nobnd versions of string functions by Pointer Bounds Checker.
1280 fchkp-use-nochk-string-functions
1281 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_use_nochk_string_functions) Init(0)
1282 Allow to use *_nochk versions of string functions by Pointer Bounds Checker.
1284 fchkp-use-static-bounds
1285 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_use_static_bounds) Init(1)
1286 Use statically initialized variable for vars bounds instead of
1287 generating them each time it is required.
1289 fchkp-use-static-const-bounds
1290 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_use_static_const_bounds) Init(-1)
1291 Use statically initialized variable for constant bounds instead of
1292 generating them each time it is required.
1294 fchkp-treat-zero-dynamic-size-as-infinite
1295 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_zero_dynamic_size_as_infinite) Init(0)
1296 With this option zero size obtained dynamically for objects with
1297 incomplete type will be treated as infinite.
1300 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_check_read) Init(1)
1301 Generate checks for all read accesses to memory.
1304 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_check_write) Init(1)
1305 Generate checks for all write accesses to memory.
1308 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_store_bounds) Init(1)
1309 Generate bounds stores for pointer writes.
1311 fchkp-instrument-calls
1312 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_instrument_calls) Init(1)
1313 Generate bounds passing for calls.
1315 fchkp-instrument-marked-only
1316 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_instrument_marked_only) Init(0)
1317 Instrument only functions marked with bnd_instrument attribute.
1320 C ObjC C++ ObjC++ LTO Report Var(flag_chkp_use_wrappers) Init(1)
1321 Transform instrumented builtin calls into calls to wrappers.
1326 static-libmpxwrappers
1330 C ObjC C++ ObjC++ LTO Report Var(flag_cilkplus) Init(0)
1334 C++ ObjC++ Var(flag_concepts)
1335 Enable support for C++ concepts.
1339 Allow the arguments of the '?' operator to have different types.
1342 C++ ObjC++ Var(flag_conserve_space)
1343 Does nothing. Preserved for backward compatibility.
1345 fconstant-string-class=
1346 ObjC ObjC++ Joined MissingArgError(no class name specified with %qs)
1347 -fconst-string-class=<name> Use class <name> for constant strings.
1350 C++ ObjC++ Joined RejectNegative UInteger Var(max_constexpr_depth) Init(512)
1351 -fconstexpr-depth=<number> Specify maximum constexpr recursion depth.
1353 fconstexpr-loop-limit=
1354 C++ ObjC++ Joined RejectNegative UInteger Var(constexpr_loop_limit) Init(262144)
1355 -fconstexpr-loop-limit=<number> Specify maximum constexpr loop iteration count.
1359 Emit debug annotations during preprocessing.
1362 C++ ObjC++ Var(flag_deduce_init_list) Init(0)
1363 -fdeduce-init-list enable deduction of std::initializer_list for a template type parameter from a brace-enclosed initializer-list.
1366 C++ ObjC++ Var(flag_declone_ctor_dtor) Init(-1)
1367 Factor complex constructors and destructors to favor space over speed.
1371 Does nothing. Preserved for backward compatibility.
1373 fdiagnostics-show-template-tree
1374 C++ ObjC++ Var(flag_diagnostics_show_template_tree) Init(0)
1375 Print hierarchical comparisons when template types are mismatched.
1379 Preprocess directives only.
1381 fdollars-in-identifiers
1383 Permit '$' as an identifier character.
1386 C ObjC C++ ObjC++ RejectNegative Var(flag_dump_ada_spec)
1387 Write all declarations as Ada code transitively.
1390 C ObjC C++ ObjC++ RejectNegative Var(flag_dump_ada_spec_slim)
1391 Write all declarations as Ada code for the given file only.
1394 C++ ObjC++ Var(flag_elide_constructors) Init(1)
1397 C++ ObjC++ Var(flag_elide_type) Init(1)
1398 -fno-elide-type Do not elide common elements in template comparisons.
1401 C++ ObjC++ Var(flag_enforce_eh_specs) Init(1)
1402 Generate code to check exception specifications.
1405 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1408 C ObjC C++ ObjC++ Joined RejectNegative
1409 -fexec-charset=<cset> Convert all strings and character constants to character set <cset>.
1411 fextended-identifiers
1413 Permit universal character names (\\u and \\U) in identifiers.
1416 C ObjC C++ ObjC++ Joined RejectNegative
1417 -finput-charset=<cset> Specify the default character set for source files.
1420 C++ ObjC++ Var(flag_extern_tls_init) Init(-1)
1421 Support dynamic initialization of thread-local variables in a different translation unit.
1424 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1427 C++ ObjC++ Var(flag_new_for_scope) Init(1)
1428 Scope of for-init-statement variables is local to the loop.
1432 Do not assume that standard C libraries and \"main\" exist.
1435 C++ ObjC++ Var(flag_no_gnu_keywords, 0)
1436 Recognize GNU-defined keywords.
1439 ObjC ObjC++ LTO Report RejectNegative Var(flag_next_runtime,0) Init(NEXT_OBJC_RUNTIME)
1440 Generate code for GNU runtime environment.
1443 C ObjC Var(flag_gnu89_inline) Init(-1)
1444 Use traditional GNU semantics for inline functions.
1447 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1450 C++ ObjC++ Optimization Alias(fexceptions) Warn({-fhandle-exceptions has been renamed -fexceptions (and is now on by default)})
1453 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1457 Assume normal C execution environment.
1460 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1461 No longer supported.
1464 C++ ObjC++ Var(flag_implement_inlines) Init(1)
1465 Export functions even if they can be inlined.
1467 fimplicit-inline-templates
1468 C++ ObjC++ Var(flag_implicit_inline_templates) Init(1)
1469 Emit implicit instantiations of inline templates.
1472 C++ ObjC++ Var(flag_implicit_templates) Init(1)
1473 Emit implicit instantiations of templates.
1475 fnew-inheriting-ctors
1476 C++ ObjC++ Var(flag_new_inheriting_ctors) Init(1)
1477 Implement C++17 inheriting constructor semantics.
1480 C++ ObjC++ Var(flag_friend_injection)
1481 Inject friend functions into enclosing namespace.
1483 fkeep-inline-dllexport
1484 C C++ ObjC ObjC++ Var(flag_keep_inline_dllexport) Init(1) Report Condition(TARGET_DLLIMPORT_DECL_ATTRIBUTES)
1485 Don't emit dllexported inline functions unless needed.
1488 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1490 flax-vector-conversions
1491 C ObjC C++ ObjC++ Var(flag_lax_vector_conversions)
1492 Allow implicit conversions between vectors with differing numbers of subparts and/or differing element types.
1495 C ObjC C++ ObjC++ Var(flag_ms_extensions)
1496 Don't warn about uses of Microsoft extensions.
1499 C ObjC C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1502 C ObjC C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1505 C ObjC C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1507 fname-mangling-version-
1508 C++ ObjC++ Joined Ignore Warn(switch %qs is no longer supported)
1511 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1514 C++ ObjC++ Var(flag_new_ttp)
1515 Implement resolution of DR 150 for matching of template template arguments.
1518 ObjC ObjC++ LTO Report RejectNegative Var(flag_next_runtime)
1519 Generate code for NeXT (Apple Mac OS X) runtime environment.
1522 ObjC ObjC++ Var(flag_nil_receivers) Init(1)
1523 Assume that receivers of Objective-C messages may be nil.
1526 ObjC ObjC++ Var(flag_local_ivars) Init(1)
1527 Allow access to instance variables as if they were local declarations within instance method implementations.
1530 ObjC ObjC++ Joined RejectNegative Enum(ivar_visibility) Var(default_ivar_visibility) Init(IVAR_VISIBILITY_PROTECTED)
1531 -fvisibility=[private|protected|public|package] Set the default symbol visibility.
1534 Name(ivar_visibility) Type(enum ivar_visibility) UnknownError(unrecognized ivar visibility value %qs)
1537 Enum(ivar_visibility) String(private) Value(IVAR_VISIBILITY_PRIVATE)
1540 Enum(ivar_visibility) String(protected) Value(IVAR_VISIBILITY_PROTECTED)
1543 Enum(ivar_visibility) String(public) Value(IVAR_VISIBILITY_PUBLIC)
1546 Enum(ivar_visibility) String(package) Value(IVAR_VISIBILITY_PACKAGE)
1549 C++ ObjC++ Var(flag_no_nonansi_builtin, 0)
1552 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1555 C++ ObjC++ Optimization Var(flag_nothrow_opt)
1556 Treat a throw() exception specification as noexcept to improve code size.
1559 ObjC ObjC++ LTO Joined Report RejectNegative UInteger Var(flag_objc_abi)
1560 Specify which ABI to use for Objective-C family code and meta-data generation.
1562 ; Generate special '- .cxx_construct' and '- .cxx_destruct' methods
1563 ; to initialize any non-POD ivars in Objective-C++ classes.
1564 fobjc-call-cxx-cdtors
1565 ObjC++ Var(flag_objc_call_cxx_cdtors)
1566 Generate special Objective-C methods to initialize/destroy non-POD C++ ivars, if needed.
1568 fobjc-direct-dispatch
1569 ObjC ObjC++ Var(flag_objc_direct_dispatch)
1570 Allow fast jumps to the message dispatcher.
1572 ; Nonzero means that we will allow new ObjC exception syntax (@throw,
1573 ; @try, etc.) in source code.
1575 ObjC ObjC++ Var(flag_objc_exceptions)
1576 Enable Objective-C exception and synchronization syntax.
1579 ObjC ObjC++ LTO Var(flag_objc_gc)
1580 Enable garbage collection (GC) in Objective-C/Objective-C++ programs.
1583 ObjC ObjC++ Var(flag_objc_nilcheck,1)
1584 Enable inline checks for nil receivers with the NeXT runtime and ABI version 2.
1586 ; Nonzero means that we generate NeXT setjmp based exceptions.
1587 fobjc-sjlj-exceptions
1588 ObjC ObjC++ Var(flag_objc_sjlj_exceptions) Init(-1)
1589 Enable Objective-C setjmp exception handling runtime.
1592 ObjC ObjC++ Var(flag_objc1_only)
1593 Conform to the Objective-C 1.0 language as implemented in GCC 4.0.
1596 C ObjC C++ ObjC++ LTO Var(flag_openacc)
1600 C ObjC C++ ObjC++ LTO Joined Var(flag_openacc_dims)
1601 Specify default OpenACC compute dimensions.
1604 C ObjC C++ ObjC++ LTO Var(flag_openmp)
1605 Enable OpenMP (implies -frecursive in Fortran).
1608 C ObjC C++ ObjC++ Var(flag_openmp_simd)
1609 Enable OpenMP's SIMD directives.
1613 Recognize C++ keywords like \"compl\" and \"xor\".
1617 Does nothing. Preserved for backward compatibility.
1624 Look for and use PCH files even when preprocessing.
1627 C++ ObjC++ Var(flag_permissive)
1628 Downgrade conformance errors to warnings.
1631 C ObjC Var(flag_plan9_extensions)
1632 Enable Plan 9 language extensions.
1636 Treat the input file as already preprocessed.
1638 ftrack-macro-expansion
1639 C ObjC C++ ObjC++ JoinedOrMissing RejectNegative UInteger
1640 ; converted into ftrack-macro-expansion=
1642 ftrack-macro-expansion=
1643 C ObjC C++ ObjC++ JoinedOrMissing RejectNegative UInteger
1644 -ftrack-macro-expansion=<0|1|2> Track locations of tokens coming from macro expansion and display them in error messages.
1647 C++ ObjC++ Var(flag_pretty_templates) Init(1)
1648 -fno-pretty-templates Do not pretty-print template specializations as the template signature followed by the arguments.
1650 fprintf-return-value
1651 C ObjC C++ ObjC++ LTO Optimization Var(flag_printf_return_value) Init(1)
1652 Treat known sprintf return values as constants.
1654 freplace-objc-classes
1655 ObjC ObjC++ LTO Var(flag_replace_objc_classes)
1656 Used in Fix-and-Continue mode to indicate that object files may be swapped in at runtime.
1660 Enable automatic template instantiation.
1663 C++ ObjC++ Optimization Var(flag_rtti) Init(1)
1664 Generate run time type descriptor information.
1667 C ObjC C++ ObjC++ LTO Optimization Var(flag_short_enums)
1668 Use the narrowest integer type possible for enumeration types.
1671 C ObjC C++ ObjC++ LTO Optimization Var(flag_short_wchar)
1672 Force the underlying type for \"wchar_t\" to be \"unsigned short\".
1675 C ObjC C++ ObjC++ Var(flag_signed_bitfields) Init(1)
1676 When \"signed\" or \"unsigned\" is not given make the bitfield signed.
1679 C ObjC C++ ObjC++ LTO Var(flag_signed_char)
1680 Make \"char\" signed by default.
1683 C++ ObjC++ Var(flag_sized_deallocation) Init(-1)
1684 Enable C++14 sized deallocation support.
1687 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1690 C ObjC Joined RejectNegative Enum(sso_struct) Var(default_sso) Init(SSO_NATIVE)
1691 -fsso-struct=[big-endian|little-endian|native] Set the default scalar storage order.
1694 Name(sso_struct) Type(enum scalar_storage_order_kind) UnknownError(unrecognized scalar storage order value %qs)
1697 Enum(sso_struct) String(big-endian) Value(SSO_BIG_ENDIAN)
1700 Enum(sso_struct) String(little-endian) Value(SSO_LITTLE_ENDIAN)
1703 Enum(sso_struct) String(native) Value(SSO_NATIVE)
1706 C++ ObjC++ Var(flag_detailed_statistics)
1707 Display statistics accumulated during compilation.
1710 C++ ObjC++ Optimization Var(flag_strict_enums)
1711 Assume that values of enumeration type are always within the minimum range of that type.
1714 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1717 C++ ObjC++ Common Alias(fstrong-eval-order=, all, none)
1718 Follow the C++17 evaluation order requirements for assignment expressions,
1719 shift, member function calls, etc.
1722 C++ ObjC++ Common Var(flag_strong_eval_order) Joined Enum(strong_eval_order) RejectNegative Init(-1)
1723 Follow the C++17 evaluation order requirements for assignment expressions,
1724 shift, member function calls, etc.
1727 Name(strong_eval_order) Type(int)
1730 Enum(strong_eval_order) String(none) Value(0)
1733 Enum(strong_eval_order) String(some) Value(1)
1736 Enum(strong_eval_order) String(all) Value(2)
1739 C ObjC C++ ObjC++ Joined RejectNegative UInteger
1740 -ftabstop=<number> Distance between tab stops for column reporting.
1742 ftemplate-backtrace-limit=
1743 C++ ObjC++ Joined RejectNegative UInteger Var(template_backtrace_limit) Init(10)
1744 Set the maximum number of template instantiation notes for a single warning or error.
1747 C++ ObjC++ Joined RejectNegative Undocumented Alias(ftemplate-depth=)
1750 C++ ObjC++ Joined RejectNegative UInteger
1751 -ftemplate-depth=<number> Specify maximum template instantiation depth.
1754 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1757 C++ ObjC++ Optimization Var(flag_threadsafe_statics) Init(1)
1758 -fno-threadsafe-statics Do not generate thread-safe code for initializing local statics.
1761 C ObjC C++ ObjC++ Var(flag_signed_bitfields, 0)
1762 When \"signed\" or \"unsigned\" is not given make the bitfield unsigned.
1765 C ObjC C++ ObjC++ LTO Var(flag_signed_char, 0)
1766 Make \"char\" unsigned by default.
1769 C++ ObjC++ Var(flag_use_cxa_atexit) Init(DEFAULT_USE_CXA_ATEXIT)
1770 Use __cxa_atexit to register destructors.
1772 fuse-cxa-get-exception-ptr
1773 C++ ObjC++ Var(flag_use_cxa_get_exception_ptr) Init(2)
1774 Use __cxa_get_exception_ptr in exception handling.
1776 fvisibility-inlines-hidden
1778 Marks all inlined functions and methods as having hidden visibility.
1780 fvisibility-ms-compat
1781 C++ ObjC++ Var(flag_visibility_ms_compat)
1782 Changes visibility to match Microsoft Visual Studio by default.
1785 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1786 No longer supported.
1789 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1790 No longer supported.
1793 C++ ObjC++ Var(flag_weak) Init(1)
1794 Emit common-like symbols as weak symbols.
1797 C ObjC C++ ObjC++ Joined RejectNegative
1798 -fwide-exec-charset=<cset> Convert all wide strings and character constants to character set <cset>.
1801 C ObjC C++ ObjC++ Var(flag_working_directory) Init(-1)
1802 Generate a #line directive pointing at the current working directory.
1805 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1806 No longer supported.
1809 ObjC ObjC++ Var(flag_zero_link)
1810 Generate lazy class lookup (via objc_getClass()) for use in Zero-Link mode.
1813 ObjC ObjC++ Driver Var(flag_gen_declaration) RejectNegative
1814 Dump declarations to a .decl file.
1816 femit-struct-debug-baseonly
1818 -femit-struct-debug-baseonly Aggressive reduced debug info for structs.
1820 femit-struct-debug-reduced
1822 -femit-struct-debug-reduced Conservative reduced debug info for structs.
1824 femit-struct-debug-detailed=
1825 C ObjC C++ ObjC++ Joined
1826 -femit-struct-debug-detailed=<spec-list> Detailed reduced debug info for structs.
1828 fext-numeric-literals
1829 C++ ObjC++ Var(flag_ext_numeric_literals) Init(1)
1830 Interpret imaginary, fixed-point, or other gnu number suffix as the corresponding
1831 number literal rather than a user-defined number literal.
1834 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)
1835 -idirafter <dir> Add <dir> to the end of the system include path.
1838 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing filename after %qs)
1839 -imacros <file> Accept definition of macros in <file>.
1842 C ObjC C++ ObjC++ Joined Separate
1843 -imultilib <dir> Set <dir> to be the multilib include subdirectory.
1846 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing filename after %qs)
1847 -include <file> Include the contents of <file> before other files.
1850 C ObjC C++ ObjC++ Joined Separate
1851 -iprefix <path> Specify <path> as a prefix for next two options.
1854 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)
1855 -isysroot <dir> Set <dir> to be the system root directory.
1858 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)
1859 -isystem <dir> Add <dir> to the start of the system include path.
1862 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)
1863 -iquote <dir> Add <dir> to the end of the quote include path.
1866 C ObjC C++ ObjC++ Joined Separate
1867 -iwithprefix <dir> Add <dir> to the end of the system include path.
1870 C ObjC C++ ObjC++ Joined Separate
1871 -iwithprefixbefore <dir> Add <dir> to the end of the main include path.
1874 C Undocumented RejectDriver
1881 Do not search standard system include directories (those specified with -isystem will still be used).
1885 Do not search standard system include directories for C++.
1888 C ObjC C++ ObjC++ Joined Separate
1889 ; Documented in common.opt
1892 C ObjC C++ ObjC++ Alias(Wpedantic)
1893 ; Documented in common.opt
1895 print-objc-runtime-info
1897 Generate C header of platform-specific features.
1901 Remap file names when including files.
1905 Conform to the ISO 1998 C++ standard revised by the 2003 technical corrigendum.
1908 C++ ObjC++ Alias(std=c++98)
1909 Conform to the ISO 1998 C++ standard revised by the 2003 technical corrigendum.
1913 Conform to the ISO 2011 C++ standard.
1916 C++ ObjC++ Alias(std=c++11) Undocumented
1917 Deprecated in favor of -std=c++11.
1920 C++ ObjC++ Alias(std=c++14) Undocumented
1921 Deprecated in favor of -std=c++14.
1925 Conform to the ISO 2014 C++ standard.
1928 C++ ObjC++ Alias(std=c++17) Undocumented
1929 Deprecated in favor of -std=c++17.
1933 Conform to the ISO 2017 C++ standard.
1937 Conform to the ISO 2020(?) C++ draft standard (experimental and incomplete support).
1941 Conform to the ISO 2011 C standard.
1944 C ObjC Alias(std=c11)
1945 Deprecated in favor of -std=c11.
1949 Conform to the ISO 2017 C standard.
1952 C ObjC Alias(std=c90)
1953 Conform to the ISO 1990 C standard.
1957 Conform to the ISO 1990 C standard.
1961 Conform to the ISO 1999 C standard.
1964 C ObjC Alias(std=c99)
1965 Deprecated in favor of -std=c99.
1969 Conform to the ISO 1998 C++ standard revised by the 2003 technical
1970 corrigendum with GNU extensions.
1973 C++ ObjC++ Alias(std=gnu++98)
1974 Conform to the ISO 1998 C++ standard revised by the 2003 technical
1975 corrigendum with GNU extensions.
1979 Conform to the ISO 2011 C++ standard with GNU extensions.
1982 C++ ObjC++ Alias(std=gnu++11) Undocumented
1983 Deprecated in favor of -std=gnu++11.
1986 C++ ObjC++ Alias(std=gnu++14) Undocumented
1987 Deprecated in favor of -std=gnu++14.
1991 Conform to the ISO 2014 C++ standard with GNU extensions.
1994 C++ ObjC++ Alias(std=gnu++17) Undocumented
1995 Deprecated in favor of -std=gnu++17.
1999 Conform to the ISO 2017 C++ standard with GNU extensions.
2003 Conform to the ISO 2020(?) C++ draft standard with GNU extensions (experimental and incomplete support).
2007 Conform to the ISO 2011 C standard with GNU extensions.
2010 C ObjC Alias(std=gnu11)
2011 Deprecated in favor of -std=gnu11.
2015 Conform to the ISO 2017 C standard with GNU extensions.
2018 C ObjC Alias(std=gnu90)
2019 Conform to the ISO 1990 C standard with GNU extensions.
2023 Conform to the ISO 1990 C standard with GNU extensions.
2027 Conform to the ISO 1999 C standard with GNU extensions.
2030 C ObjC Alias(std=gnu99)
2031 Deprecated in favor of -std=gnu99.
2034 C ObjC Alias(std=c90)
2035 Conform to the ISO 1990 C standard.
2039 Conform to the ISO 1990 C standard as amended in 1994.
2042 C ObjC Alias(std=c99)
2043 Conform to the ISO 1999 C standard.
2046 C ObjC Alias(std=c99)
2047 Deprecated in favor of -std=iso9899:1999.
2050 C ObjC Alias(std=c11)
2051 Conform to the ISO 2011 C standard.
2054 C ObjC Alias(std=c17)
2055 Conform to the ISO 2017 C standard.
2062 Enable traditional preprocessing.
2066 -trigraphs Support ISO C trigraphs.
2069 C ObjC C++ ObjC++ Var(flag_undef)
2070 Do not predefine system-specific and GCC-specific macros.
2074 ; Documented in common.opt
2078 ; Documented in common.opt
2080 ; This comment is to ensure we retain the blank line above.