1 ; Options for the C, ObjC, C++ and ObjC++ front ends.
2 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009
3 ; 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 for a description of this file's format.
23 ; Please try to keep this file in ASCII collating order.
38 C ObjC C++ ObjC++ Joined Separate
41 C ObjC C++ ObjC++ Joined Separate
42 -A<question>=<answer> Assert the <answer> to <question>. Putting '-' before <question> disables the <answer> to <question>
46 Do not discard comments
50 Do not discard comments in macro expansions
53 C ObjC C++ ObjC++ Joined Separate
54 -D<macro>[=<val>] Define a <macro> with <val> as its value. If just <macro> is given, <val> is taken to be 1
57 C ObjC C++ ObjC++ Undocumented
60 C ObjC C++ ObjC++ Joined Separate
61 -F <dir> Add <dir> to the end of the main framework include path
65 Print the name of header files as they are used
68 C ObjC C++ ObjC++ Joined Separate
69 -I <dir> Add <dir> to the end of the main include path
73 Generate make dependencies
76 C ObjC C++ ObjC++ Separate
77 Generate make dependencies and compile
80 C ObjC C++ ObjC++ Joined Separate
81 -MF <file> Write dependency output to the given file
85 Treat missing header files as generated files
89 Like -M but ignore system header files
92 C ObjC C++ ObjC++ Separate
93 Like -MD but ignore system header files
97 Generate phony targets for all headers
100 C ObjC C++ ObjC++ Joined Separate
101 -MQ <target> Add a MAKE-quoted target
104 C ObjC C++ ObjC++ Joined Separate
105 -MT <target> Add an unquoted target
109 Do not generate #line directives
112 C ObjC C++ ObjC++ Joined Separate
113 -U<macro> Undefine <macro>
116 C ObjC C++ ObjC++ Var(warn_abi) Warning
117 Warn about things that will change when compiling with an ABI-compliant compiler
120 C ObjC C++ ObjC++ Var(warn_psabi) Init(1) Undocumented
123 C ObjC C++ ObjC++ Var(warn_address) Warning
124 Warn about suspicious uses of memory addresses
127 C ObjC C++ ObjC++ Warning
128 Enable most warning messages
131 ObjC ObjC++ Var(warn_assign_intercept) Warning
132 Warn whenever an Objective-C assignment is being intercepted by the garbage collector
135 C ObjC Var(warn_bad_function_cast) Warning
136 Warn about casting functions to incompatible types
138 Wbuiltin-macro-redefined
139 C ObjC C++ ObjC++ Warning
140 Warn when a built-in preprocessor macro is undefined or redefined
143 C ObjC Var(warn_cxx_compat) Warning
144 Warn about C constructs that are not in the common subset of C and C++
147 C++ ObjC++ Var(warn_cxx0x_compat) Warning
148 Warn about C++ constructs whose meaning differs between ISO C++ 1998 and ISO C++ 200x
151 C ObjC C++ ObjC++ Var(warn_cast_qual) Warning
152 Warn about casts which discard qualifiers
155 C ObjC C++ ObjC++ Var(warn_char_subscripts) Warning
156 Warn about subscripts whose type is \"char\"
159 C ObjC C++ ObjC++ Var(warn_clobbered) Init(-1) Warning
160 Warn about variables that might be changed by \"longjmp\" or \"vfork\"
163 C ObjC C++ ObjC++ Warning
164 Warn about possibly nested block comments, and C++ comments spanning more than one physical line
167 C ObjC C++ ObjC++ Warning
168 Synonym for -Wcomment
171 C ObjC C++ ObjC++ Var(warn_conversion) Warning
172 Warn for implicit type conversions that may change a value
175 C ObjC C++ ObjC++ Var(warn_sign_conversion) Init(-1)
176 Warn for implicit type conversions between signed and unsigned integers
179 C++ ObjC++ Var(warn_ctor_dtor_privacy) Warning
180 Warn when all constructors and destructors are private
182 Wdeclaration-after-statement
183 C ObjC Var(warn_declaration_after_statement) Warning
184 Warn when a declaration is found after a statement
187 C C++ ObjC ObjC++ Var(warn_deprecated) Init(1) Warning
188 Warn if a deprecated compiler feature, class, method, or field is used
191 C ObjC C++ ObjC++ Var(warn_div_by_zero) Init(1) Warning
192 Warn about compile-time integer division by zero
195 C++ ObjC++ Var(warn_ecpp) Warning
196 Warn about violations of Effective C++ style rules
199 C ObjC C++ ObjC++ Var(warn_empty_body) Init(-1) Warning
200 Warn about an empty body in an if or else statement
203 C ObjC C++ ObjC++ Warning
204 Warn about stray tokens after #elif and #endif
207 C++ ObjC++ Var(warn_enum_compare) Init(1) Warning
208 Warn about comparison of different enum types
212 ; Documented in common.opt
214 Werror-implicit-function-declaration
215 C ObjC RejectNegative Warning
216 This switch is deprecated; use -Werror=implicit-function-declaration instead
219 C ObjC C++ ObjC++ Var(warn_float_equal) Warning
220 Warn if testing floating point numbers for equality
223 C ObjC C++ ObjC++ Warning
224 Warn about printf/scanf/strftime/strfmon format string anomalies
227 C ObjC C++ ObjC++ Var(warn_format_extra_args) Warning
228 Warn if passing too many arguments to a function for its format string
231 C ObjC C++ ObjC++ Var(warn_format_nonliteral) Warning
232 Warn about format strings that are not literals
235 C ObjC C++ ObjC++ Var(warn_format_contains_nul) Warning
236 Warn about format strings that contain NUL bytes
239 C ObjC C++ ObjC++ Var(warn_format_security) Warning
240 Warn about possible security problems with format functions
243 C ObjC C++ ObjC++ Var(warn_format_y2k) Warning
244 Warn about strftime formats yielding 2-digit years
247 C ObjC Var(warn_format_zero_length) Warning
248 Warn about zero-length formats
251 C ObjC C++ ObjC++ Joined Warning
254 C C++ Var(warn_ignored_qualifiers) Init(-1) Warning
255 Warn whenever type qualifiers are ignored.
258 C ObjC C++ ObjC++ Var(warn_init_self) Warning
259 Warn about variables which are initialized to themselves
262 C ObjC C++ ObjC++ Warning
264 Wimplicit-function-declaration
265 C ObjC Var(warn_implicit_function_declaration) Init(-1) Warning
266 Warn about implicit function declarations
269 C ObjC Var(warn_implicit_int) Warning
270 Warn when a declaration does not specify a type
273 C ObjC C++ ObjC++ Undocumented
276 C ObjC Var(warn_int_to_pointer_cast) Init(1) Warning
277 Warn when there is a cast to a pointer from an integer of a different size
280 C++ ObjC++ Var(warn_invalid_offsetof) Init(1) Warning
281 Warn about invalid uses of the \"offsetof\" macro
284 C ObjC C++ ObjC++ Warning
285 Warn about PCH files that are found but not used
288 C ObjC C++ ObjC++ Var(warn_long_long) Init(1) Warning
289 Do not warn about using \"long long\" when -pedantic
292 C ObjC C++ ObjC++ Var(warn_main) Init(-1) Warning
293 Warn about suspicious declarations of \"main\"
296 C ObjC C++ ObjC++ Var(warn_missing_braces) Warning
297 Warn about possibly missing braces around initializers
299 Wmissing-declarations
300 C ObjC C++ ObjC++ Var(warn_missing_declarations) Warning
301 Warn about global functions without previous declarations
303 Wmissing-field-initializers
304 C ObjC C++ ObjC++ Var(warn_missing_field_initializers) Init(-1) Warning
305 Warn about missing fields in struct initializers
307 Wmissing-format-attribute
308 C ObjC C++ ObjC++ Var(warn_missing_format_attribute) Warning
309 Warn about functions which might be candidates for format attributes
311 Wmissing-include-dirs
312 C ObjC C++ ObjC++ Warning
313 Warn about user-specified include directories that do not exist
315 Wmissing-parameter-type
316 C ObjC Var(warn_missing_parameter_type) Init(-1) Warning
317 Warn about function parameters declared without a type specifier in K&R-style functions
320 C ObjC Var(warn_missing_prototypes) Warning
321 Warn about global functions without prototypes
324 C ObjC C++ ObjC++ Warning
325 Warn about use of multi-character character constants
328 C ObjC Var(warn_nested_externs) Warning
329 Warn about \"extern\" declarations not at file scope
332 C++ ObjC++ Var(warn_nontemplate_friend) Init(1) Warning
333 Warn when non-templatized friend functions are declared within a template
336 C++ ObjC++ Var(warn_nonvdtor) Warning
337 Warn about non-virtual destructors
340 C ObjC Var(warn_nonnull) Warning
341 Warn about NULL being passed to argument slots marked as requiring non-NULL
344 C ObjC C++ ObjC++ Joined Warning
345 -Wnormalized=<id|nfc|nfkc> Warn about non-normalised Unicode strings
348 C++ ObjC++ Var(warn_old_style_cast) Warning
349 Warn if a C-style cast is used in a program
351 Wold-style-declaration
352 C ObjC Var(warn_old_style_declaration) Init(-1) Warning
353 Warn for obsolescent usage in a declaration
355 Wold-style-definition
356 C ObjC Var(warn_old_style_definition) Warning
357 Warn if an old-style parameter definition is used
360 C ObjC C++ ObjC++ Var(warn_overlength_strings) Init(-1) Warning
361 Warn if a string is longer than the maximum portable length specified by the standard
364 C++ ObjC++ Var(warn_overloaded_virtual) Warning
365 Warn about overloaded virtual function names
368 C ObjC Var(warn_override_init) Init(-1) Warning
369 Warn about overriding initializers without side effects
371 Wpacked-bitfield-compat
372 C ObjC C++ ObjC++ Var(warn_packed_bitfield_compat) Init(-1) Warning
373 Warn about packed bit-fields whose offset changed in GCC 4.4
376 C ObjC C++ ObjC++ Var(warn_parentheses) Warning
377 Warn about possibly missing parentheses
380 C++ ObjC++ Var(warn_pmf2ptr) Init(1) Warning
381 Warn when converting the type of pointers to member functions
384 C ObjC C++ ObjC++ Var(warn_pointer_arith) Warning
385 Warn about function pointer arithmetic
388 C ObjC Var(warn_pointer_to_int_cast) Init(1) Warning
389 Warn when a pointer is cast to an integer of a different size
392 C ObjC C++ ObjC++ Var(warn_pragmas) Init(1) Warning
393 Warn about misuses of pragmas
396 ObjC ObjC++ Var(warn_protocol) Init(1) Warning
397 Warn if inherited methods are unimplemented
400 C ObjC C++ ObjC++ Var(warn_redundant_decls) Warning
401 Warn about multiple declarations of the same object
404 C++ ObjC++ Var(warn_reorder) Warning
405 Warn when the compiler reorders code
408 C ObjC C++ ObjC++ Var(warn_return_type) Warning
409 Warn whenever a function's return type defaults to \"int\" (C), or about inconsistent return types (C++)
412 ObjC ObjC++ Var(warn_selector) Warning
413 Warn if a selector has multiple methods
416 C ObjC C++ ObjC++ Var(warn_sequence_point) Warning
417 Warn about possible violations of sequence point rules
420 C ObjC C++ ObjC++ Var(warn_sign_compare) Init(-1) Warning
421 Warn about signed-unsigned comparisons
424 C++ ObjC++ Var(warn_sign_promo) Warning
425 Warn when overload promotes from unsigned to signed
427 Wstrict-null-sentinel
429 Warn about uncasted NULL used as sentinel
432 C ObjC Var(warn_strict_prototypes) Warning
433 Warn about unprototyped function declarations
435 Wstrict-selector-match
436 ObjC ObjC++ Var(warn_strict_selector_match) Warning
437 Warn if type signatures of candidate methods do not match exactly
440 C C++ Var(warn_sync_nand) Init(1) Warning
441 Warn when __sync_fetch_and_nand and __sync_nand_and_fetch built-in functions are used
444 C++ ObjC++ Var(warn_synth) Warning
445 Deprecated. This switch has no effect
448 C ObjC C++ ObjC++ Warning
449 ; Documented in common.opt
452 C ObjC Var(warn_traditional) Warning
453 Warn about features not present in traditional C
455 Wtraditional-conversion
456 C ObjC Var(warn_traditional_conversion) Warning
457 Warn of prototypes causing type conversions different from what would happen in the absence of prototype
460 C ObjC C++ ObjC++ Warning
461 Warn if trigraphs are encountered that might affect the meaning of the program
464 ObjC ObjC++ Var(warn_undeclared_selector) Warning
465 Warn about @selector()s without previously declared methods
468 C ObjC C++ ObjC++ Warning
469 Warn if an undefined macro is used in an #if directive
472 C ObjC C++ ObjC++ Warning
473 Warn about unrecognized pragmas
476 C ObjC C++ ObjC++ Warning
477 Warn about macros defined in the main file that are not used
480 C ObjC C++ ObjC++ Warning
481 Do not warn about using variadic macros when -pedantic
484 C ObjC C++ ObjC++ Var(warn_vla) Init(-1) Warning
485 Warn if a variable length array is used
487 Wvolatile-register-var
488 C ObjC C++ ObjC++ Var(warn_volatile_register_var) Warning
489 Warn when a register variable is declared volatile
492 C ObjC C++ ObjC++ Var(warn_write_strings) Warning
493 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.
496 C ObjC Var(warn_pointer_sign) Init(-1) Warning
497 Warn when a pointer differs in signedness in an assignment
501 A synonym for -std=c89 (for C) or -std=c++98 (for C++)
504 C ObjC C++ ObjC++ Joined
505 ; Documented in common.opt. FIXME - what about -dI, -dD, -dN and -dD?
509 Enforce class member access control semantics
514 falt-external-templates
516 Change when template instances are emitted
520 Recognize the \"asm\" keyword
524 Recognize built-in functions
527 C ObjC C++ ObjC++ Joined
531 Check the return value of new
535 Allow the arguments of the '?' operator to have different types
539 Reduce the size of object files
541 fconstant-string-class=
543 -fconst-string-class=<name> Use class <name> for constant strings
547 Inline member functions by default
551 Preprocess directives only.
553 fdollars-in-identifiers
555 Permit '$' as an identifier character
562 Generate code to check exception specifications
568 C ObjC C++ ObjC++ Joined RejectNegative
569 -fexec-charset=<cset> Convert all strings and character constants to character set <cset>
571 fextended-identifiers
573 Permit universal character names (\\u and \\U) in identifiers
576 C ObjC C++ ObjC++ Joined RejectNegative
577 -finput-charset=<cset> Specify the default character set for source files
585 Scope of for-init-statement variables is local to the loop
589 Do not assume that standard C libraries and \"main\" exist
593 Recognize GNU-defined keywords
597 Generate code for GNU runtime environment
600 C ObjC Var(flag_gnu89_inline) Init(-1)
601 Use traditional GNU semantics for inline functions
607 C++ ObjC++ Optimization
614 Assume normal C execution environment
618 Enable support for huge objects
622 Export functions even if they can be inlined
624 fimplicit-inline-templates
626 Emit implicit instantiations of inline templates
630 Emit implicit instantiations of templates
633 C++ ObjC++ Var(flag_friend_injection)
634 Inject friend functions into enclosing namespace
639 flax-vector-conversions
641 Allow implicit conversions between vectors with differing numbers of subparts and/or differing element types.
645 Don't warn about uses of Microsoft extensions
647 fname-mangling-version-
655 Generate code for NeXT (Apple Mac OS X) runtime environment
659 Assume that receivers of Objective-C messages may be nil
667 ; Generate special '- .cxx_construct' and '- .cxx_destruct' methods
668 ; to initialize any non-POD ivars in Objective-C++ classes.
669 fobjc-call-cxx-cdtors
670 ObjC++ Var(flag_objc_call_cxx_cdtors)
671 Generate special Objective-C methods to initialize/destroy non-POD C++ ivars, if needed
673 fobjc-direct-dispatch
674 ObjC ObjC++ Var(flag_objc_direct_dispatch)
675 Allow fast jumps to the message dispatcher
677 ; Nonzero means that we will allow new ObjC exception syntax (@throw,
678 ; @try, etc.) in source code.
680 ObjC ObjC++ Var(flag_objc_exceptions)
681 Enable Objective-C exception and synchronization syntax
684 ObjC ObjC++ Var(flag_objc_gc)
685 Enable garbage collection (GC) in Objective-C/Objective-C++ programs
687 ; Nonzero means that we generate NeXT setjmp based exceptions.
688 fobjc-sjlj-exceptions
689 ObjC ObjC++ Var(flag_objc_sjlj_exceptions) Init(-1)
690 Enable Objective-C setjmp exception handling runtime
693 C ObjC C++ ObjC++ Var(flag_openmp)
694 Enable OpenMP (implies -frecursive in Fortran)
698 Recognize C++ keywords like \"compl\" and \"xor\"
702 Enable optional diagnostics
709 Look for and use PCH files even when preprocessing
713 Downgrade conformance errors to warnings
717 Treat the input file as already preprocessed
721 -fno-pretty-templates Do not pretty-print template specializations as the template signature followed by the arguments
723 freplace-objc-classes
725 Used in Fix-and-Continue mode to indicate that object files may be swapped in at runtime
729 Enable automatic template instantiation
732 C++ ObjC++ Optimization
733 Generate run time type descriptor information
736 C ObjC C++ ObjC++ Optimization
737 Use the same size for double as for float
740 C ObjC C++ ObjC++ Optimization
741 Use the narrowest integer type possible for enumeration types
744 C ObjC C++ ObjC++ Optimization
745 Force the underlying type for \"wchar_t\" to be \"unsigned short\"
749 When \"signed\" or \"unsigned\" is not given make the bitfield signed
753 Make \"char\" signed by default
760 Display statistics accumulated during compilation
766 C ObjC C++ ObjC++ Joined RejectNegative UInteger
767 -ftabstop=<number> Distance between tab stops for column reporting
770 C++ ObjC++ Joined RejectNegative UInteger
771 -ftemplate-depth-<number> Specify maximum template instantiation depth
777 C++ ObjC++ Optimization
778 -fno-threadsafe-statics Do not generate thread-safe code for initializing local statics
782 When \"signed\" or \"unsigned\" is not given make the bitfield unsigned
786 Make \"char\" unsigned by default
790 Use __cxa_atexit to register destructors
792 fuse-cxa-get-exception-ptr
794 Use __cxa_get_exception_ptr in exception handling
796 fvisibility-inlines-hidden
798 Marks all inlined methods as having hidden visibility
800 fvisibility-ms-compat
801 C++ ObjC++ Var(flag_visibility_ms_compat)
802 Changes visibility to match Microsoft Visual Studio by default
806 Discard unused virtual functions
810 Implement vtables using thunks
814 Emit common-like symbols as weak symbols
817 C ObjC C++ ObjC++ Joined RejectNegative
818 -fwide-exec-charset=<cset> Convert all wide strings and character constants to character set <cset>
822 Generate a #line directive pointing at the current working directory
826 Emit cross referencing information
830 Generate lazy class lookup (via objc_getClass()) for use in Zero-Link mode
834 Dump declarations to a .decl file
836 femit-struct-debug-baseonly
838 -femit-struct-debug-baseonly Aggressive reduced debug info for structs
840 femit-struct-debug-reduced
842 -femit-struct-debug-reduced Conservative reduced debug info for structs
844 femit-struct-debug-detailed=
845 C ObjC C++ ObjC++ Joined
846 -femit-struct-debug-detailed=<spec-list> Detailed reduced debug info for structs
849 C ObjC C++ ObjC++ Joined Separate
850 -idirafter <dir> Add <dir> to the end of the system include path
853 C ObjC C++ ObjC++ Joined Separate
854 -imacros <file> Accept definition of macros in <file>
857 C ObjC C++ ObjC++ Joined Separate
858 -imultilib <dir> Set <dir> to be the multilib include subdirectory
861 C ObjC C++ ObjC++ Joined Separate
862 -include <file> Include the contents of <file> before other files
865 C ObjC C++ ObjC++ Joined Separate
866 -iprefix <path> Specify <path> as a prefix for next two options
869 C ObjC C++ ObjC++ Joined Separate
870 -isysroot <dir> Set <dir> to be the system root directory
873 C ObjC C++ ObjC++ Joined Separate
874 -isystem <dir> Add <dir> to the start of the system include path
877 C ObjC C++ ObjC++ Joined Separate
878 -iquote <dir> Add <dir> to the end of the quote include path
881 C ObjC C++ ObjC++ Joined Separate
882 -iwithprefix <dir> Add <dir> to the end of the system include path
885 C ObjC C++ ObjC++ Joined Separate
886 -iwithprefixbefore <dir> Add <dir> to the end of the main include path
892 C ObjC C++ ObjC++ Undocumented
896 Do not search standard system include directories (those specified with -isystem will still be used)
900 Do not search standard system include directories for C++
903 C ObjC C++ ObjC++ Joined Separate
904 ; Documented in common.opt
908 ; Documented in common.opt
912 ; Documented in common.opt
914 print-objc-runtime-info
916 Generate C header of platform-specific features
920 Print a checksum of the executable for PCH validity checking, and stop
924 Remap file names when including files
928 Conform to the ISO 1998 C++ standard
932 Conform to the ISO 1998 C++ standard, with extensions that are likely to
933 become a part of the upcoming ISO C++ standard, dubbed C++0x. Note that the
934 extensions enabled by this mode are experimental and may be removed in
935 future releases of GCC.
939 Conform to the ISO 1990 C standard
943 Conform to the ISO 1999 C standard
947 Deprecated in favor of -std=c99
951 Conform to the ISO 1998 C++ standard with GNU extensions
955 Conform to the ISO 1998 C++ standard, with GNU extensions and
956 extensions that are likely to become a part of the upcoming ISO C++
957 standard, dubbed C++0x. Note that the extensions enabled by this mode
958 are experimental and may be removed in future releases of GCC.
962 Conform to the ISO 1990 C standard with GNU extensions
966 Conform to the ISO 1999 C standard with GNU extensions
970 Deprecated in favor of -std=gnu99
974 Conform to the ISO 1990 C standard
978 Conform to the ISO 1990 C standard as amended in 1994
982 Conform to the ISO 1999 C standard
986 Deprecated in favor of -std=iso9899:1999
990 Enable traditional preprocessing
994 -trigraphs Support ISO C trigraphs
998 Do not predefine system-specific and GCC-specific macros
1001 Common C ObjC C++ ObjC++
1002 Enable verbose output
1006 ; Documented in common.opt
1008 ; This comment is to ensure we retain the blank line above.