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 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 Var(warn_jump_misses_init) Init(-1) Warning
289 Warn when a jump misses a variable initialization
292 C ObjC C++ ObjC++ Var(warn_logical_op) Init(0) Warning
293 Warn when a logical operator is suspiciously always evaluating to true or false
296 C ObjC C++ ObjC++ Var(warn_long_long) Init(-1) Warning
297 Do not warn about using \"long long\" when -pedantic
300 C ObjC C++ ObjC++ Var(warn_main) Init(-1) Warning
301 Warn about suspicious declarations of \"main\"
304 C ObjC C++ ObjC++ Var(warn_missing_braces) Warning
305 Warn about possibly missing braces around initializers
307 Wmissing-declarations
308 C ObjC C++ ObjC++ Var(warn_missing_declarations) Warning
309 Warn about global functions without previous declarations
311 Wmissing-field-initializers
312 C ObjC C++ ObjC++ Var(warn_missing_field_initializers) Init(-1) Warning
313 Warn about missing fields in struct initializers
315 Wmissing-format-attribute
316 C ObjC C++ ObjC++ Var(warn_missing_format_attribute) Warning
317 Warn about functions which might be candidates for format attributes
319 Wmissing-include-dirs
320 C ObjC C++ ObjC++ Warning
321 Warn about user-specified include directories that do not exist
323 Wmissing-parameter-type
324 C ObjC Var(warn_missing_parameter_type) Init(-1) Warning
325 Warn about function parameters declared without a type specifier in K&R-style functions
328 C ObjC Var(warn_missing_prototypes) Warning
329 Warn about global functions without prototypes
332 C ObjC C++ ObjC++ Warning
333 Warn about use of multi-character character constants
336 C ObjC Var(warn_nested_externs) Warning
337 Warn about \"extern\" declarations not at file scope
340 C++ ObjC++ Var(warn_nontemplate_friend) Init(1) Warning
341 Warn when non-templatized friend functions are declared within a template
344 C++ ObjC++ Var(warn_nonvdtor) Warning
345 Warn about non-virtual destructors
348 C ObjC Var(warn_nonnull) Warning
349 Warn about NULL being passed to argument slots marked as requiring non-NULL
352 C ObjC C++ ObjC++ Joined Warning
353 -Wnormalized=<id|nfc|nfkc> Warn about non-normalised Unicode strings
356 C++ ObjC++ Var(warn_old_style_cast) Warning
357 Warn if a C-style cast is used in a program
359 Wold-style-declaration
360 C ObjC Var(warn_old_style_declaration) Init(-1) Warning
361 Warn for obsolescent usage in a declaration
363 Wold-style-definition
364 C ObjC Var(warn_old_style_definition) Warning
365 Warn if an old-style parameter definition is used
368 C ObjC C++ ObjC++ Var(warn_overlength_strings) Init(-1) Warning
369 Warn if a string is longer than the maximum portable length specified by the standard
372 C++ ObjC++ Var(warn_overloaded_virtual) Warning
373 Warn about overloaded virtual function names
376 C ObjC Var(warn_override_init) Init(-1) Warning
377 Warn about overriding initializers without side effects
379 Wpacked-bitfield-compat
380 C ObjC C++ ObjC++ Var(warn_packed_bitfield_compat) Init(-1) Warning
381 Warn about packed bit-fields whose offset changed in GCC 4.4
384 C ObjC C++ ObjC++ Var(warn_parentheses) Warning
385 Warn about possibly missing parentheses
388 C++ ObjC++ Var(warn_pmf2ptr) Init(1) Warning
389 Warn when converting the type of pointers to member functions
392 C ObjC C++ ObjC++ Var(warn_pointer_arith) Warning
393 Warn about function pointer arithmetic
396 C ObjC Var(warn_pointer_to_int_cast) Init(1) Warning
397 Warn when a pointer is cast to an integer of a different size
400 C ObjC C++ ObjC++ Var(warn_pragmas) Init(1) Warning
401 Warn about misuses of pragmas
404 ObjC ObjC++ Var(warn_protocol) Init(1) Warning
405 Warn if inherited methods are unimplemented
408 C ObjC C++ ObjC++ Var(warn_redundant_decls) Warning
409 Warn about multiple declarations of the same object
412 C++ ObjC++ Var(warn_reorder) Warning
413 Warn when the compiler reorders code
416 C ObjC C++ ObjC++ Var(warn_return_type) Warning
417 Warn whenever a function's return type defaults to \"int\" (C), or about inconsistent return types (C++)
420 ObjC ObjC++ Var(warn_selector) Warning
421 Warn if a selector has multiple methods
424 C ObjC C++ ObjC++ Var(warn_sequence_point) Warning
425 Warn about possible violations of sequence point rules
428 C ObjC C++ ObjC++ Var(warn_sign_compare) Init(-1) Warning
429 Warn about signed-unsigned comparisons
432 C++ ObjC++ Var(warn_sign_promo) Warning
433 Warn when overload promotes from unsigned to signed
435 Wstrict-null-sentinel
437 Warn about uncasted NULL used as sentinel
440 C ObjC Var(warn_strict_prototypes) Warning
441 Warn about unprototyped function declarations
443 Wstrict-selector-match
444 ObjC ObjC++ Var(warn_strict_selector_match) Warning
445 Warn if type signatures of candidate methods do not match exactly
448 C C++ Var(warn_sync_nand) Init(1) Warning
449 Warn when __sync_fetch_and_nand and __sync_nand_and_fetch built-in functions are used
452 C++ ObjC++ Var(warn_synth) Warning
453 Deprecated. This switch has no effect
456 C ObjC C++ ObjC++ Warning
457 ; Documented in common.opt
460 C ObjC Var(warn_traditional) Warning
461 Warn about features not present in traditional C
463 Wtraditional-conversion
464 C ObjC Var(warn_traditional_conversion) Warning
465 Warn of prototypes causing type conversions different from what would happen in the absence of prototype
468 C ObjC C++ ObjC++ Warning
469 Warn if trigraphs are encountered that might affect the meaning of the program
472 ObjC ObjC++ Var(warn_undeclared_selector) Warning
473 Warn about @selector()s without previously declared methods
476 C ObjC C++ ObjC++ Warning
477 Warn if an undefined macro is used in an #if directive
480 C ObjC C++ ObjC++ Warning
481 Warn about unrecognized pragmas
483 Wunsuffixed-float-constants
484 C ObjC Var(warn_unsuffixed_float_constants) Warning
485 Warn about unsuffixed float constants
488 C ObjC C++ ObjC++ Warning
489 Warn about macros defined in the main file that are not used
492 C ObjC C++ ObjC++ Warning
493 Do not warn about using variadic macros when -pedantic
496 C ObjC C++ ObjC++ Var(warn_vla) Init(-1) Warning
497 Warn if a variable length array is used
499 Wvolatile-register-var
500 C ObjC C++ ObjC++ Var(warn_volatile_register_var) Warning
501 Warn when a register variable is declared volatile
504 C ObjC C++ ObjC++ Var(warn_write_strings) Warning
505 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.
508 C ObjC Var(warn_pointer_sign) Init(-1) Warning
509 Warn when a pointer differs in signedness in an assignment
513 A synonym for -std=c89 (for C) or -std=c++98 (for C++)
516 C ObjC C++ ObjC++ Joined
517 ; Documented in common.opt. FIXME - what about -dI, -dD, -dN and -dD?
521 Enforce class member access control semantics
526 falt-external-templates
528 Change when template instances are emitted
532 Recognize the \"asm\" keyword
536 Recognize built-in functions
539 C ObjC C++ ObjC++ Joined
543 Check the return value of new
547 Allow the arguments of the '?' operator to have different types
551 Reduce the size of object files
553 fconstant-string-class=
555 -fconst-string-class=<name> Use class <name> for constant strings
559 Inline member functions by default
563 Preprocess directives only.
565 fdollars-in-identifiers
567 Permit '$' as an identifier character
574 Generate code to check exception specifications
580 C ObjC C++ ObjC++ Joined RejectNegative
581 -fexec-charset=<cset> Convert all strings and character constants to character set <cset>
583 fextended-identifiers
585 Permit universal character names (\\u and \\U) in identifiers
588 C ObjC C++ ObjC++ Joined RejectNegative
589 -finput-charset=<cset> Specify the default character set for source files
597 Scope of for-init-statement variables is local to the loop
601 Do not assume that standard C libraries and \"main\" exist
605 Recognize GNU-defined keywords
609 Generate code for GNU runtime environment
612 C ObjC Var(flag_gnu89_inline) Init(-1)
613 Use traditional GNU semantics for inline functions
619 C++ ObjC++ Optimization
626 Assume normal C execution environment
630 Enable support for huge objects
634 Export functions even if they can be inlined
636 fimplicit-inline-templates
638 Emit implicit instantiations of inline templates
642 Emit implicit instantiations of templates
645 C++ ObjC++ Var(flag_friend_injection)
646 Inject friend functions into enclosing namespace
651 flax-vector-conversions
653 Allow implicit conversions between vectors with differing numbers of subparts and/or differing element types.
657 Don't warn about uses of Microsoft extensions
659 fname-mangling-version-
667 Generate code for NeXT (Apple Mac OS X) runtime environment
671 Assume that receivers of Objective-C messages may be nil
679 ; Generate special '- .cxx_construct' and '- .cxx_destruct' methods
680 ; to initialize any non-POD ivars in Objective-C++ classes.
681 fobjc-call-cxx-cdtors
682 ObjC++ Var(flag_objc_call_cxx_cdtors)
683 Generate special Objective-C methods to initialize/destroy non-POD C++ ivars, if needed
685 fobjc-direct-dispatch
686 ObjC ObjC++ Var(flag_objc_direct_dispatch)
687 Allow fast jumps to the message dispatcher
689 ; Nonzero means that we will allow new ObjC exception syntax (@throw,
690 ; @try, etc.) in source code.
692 ObjC ObjC++ Var(flag_objc_exceptions)
693 Enable Objective-C exception and synchronization syntax
696 ObjC ObjC++ Var(flag_objc_gc)
697 Enable garbage collection (GC) in Objective-C/Objective-C++ programs
699 ; Nonzero means that we generate NeXT setjmp based exceptions.
700 fobjc-sjlj-exceptions
701 ObjC ObjC++ Var(flag_objc_sjlj_exceptions) Init(-1)
702 Enable Objective-C setjmp exception handling runtime
705 C ObjC C++ ObjC++ Var(flag_openmp)
706 Enable OpenMP (implies -frecursive in Fortran)
710 Recognize C++ keywords like \"compl\" and \"xor\"
714 Enable optional diagnostics
721 Look for and use PCH files even when preprocessing
725 Downgrade conformance errors to warnings
729 Treat the input file as already preprocessed
733 -fno-pretty-templates Do not pretty-print template specializations as the template signature followed by the arguments
735 freplace-objc-classes
737 Used in Fix-and-Continue mode to indicate that object files may be swapped in at runtime
741 Enable automatic template instantiation
744 C++ ObjC++ Optimization
745 Generate run time type descriptor information
748 C ObjC C++ ObjC++ Optimization
749 Use the same size for double as for float
752 C ObjC C++ ObjC++ Optimization
753 Use the narrowest integer type possible for enumeration types
756 C ObjC C++ ObjC++ Optimization
757 Force the underlying type for \"wchar_t\" to be \"unsigned short\"
761 When \"signed\" or \"unsigned\" is not given make the bitfield signed
765 Make \"char\" signed by default
772 Display statistics accumulated during compilation
778 C ObjC C++ ObjC++ Joined RejectNegative UInteger
779 -ftabstop=<number> Distance between tab stops for column reporting
782 C++ ObjC++ Joined RejectNegative UInteger
783 -ftemplate-depth-<number> Specify maximum template instantiation depth
789 C++ ObjC++ Optimization
790 -fno-threadsafe-statics Do not generate thread-safe code for initializing local statics
794 When \"signed\" or \"unsigned\" is not given make the bitfield unsigned
798 Make \"char\" unsigned by default
802 Use __cxa_atexit to register destructors
804 fuse-cxa-get-exception-ptr
806 Use __cxa_get_exception_ptr in exception handling
808 fvisibility-inlines-hidden
810 Marks all inlined methods as having hidden visibility
812 fvisibility-ms-compat
813 C++ ObjC++ Var(flag_visibility_ms_compat)
814 Changes visibility to match Microsoft Visual Studio by default
818 Discard unused virtual functions
822 Implement vtables using thunks
826 Emit common-like symbols as weak symbols
829 C ObjC C++ ObjC++ Joined RejectNegative
830 -fwide-exec-charset=<cset> Convert all wide strings and character constants to character set <cset>
834 Generate a #line directive pointing at the current working directory
838 Emit cross referencing information
842 Generate lazy class lookup (via objc_getClass()) for use in Zero-Link mode
846 Dump declarations to a .decl file
848 femit-struct-debug-baseonly
850 -femit-struct-debug-baseonly Aggressive reduced debug info for structs
852 femit-struct-debug-reduced
854 -femit-struct-debug-reduced Conservative reduced debug info for structs
856 femit-struct-debug-detailed=
857 C ObjC C++ ObjC++ Joined
858 -femit-struct-debug-detailed=<spec-list> Detailed reduced debug info for structs
861 C ObjC C++ ObjC++ Joined Separate
862 -idirafter <dir> Add <dir> to the end of the system include path
865 C ObjC C++ ObjC++ Joined Separate
866 -imacros <file> Accept definition of macros in <file>
869 C ObjC C++ ObjC++ Joined Separate
870 -imultilib <dir> Set <dir> to be the multilib include subdirectory
873 C ObjC C++ ObjC++ Joined Separate
874 -include <file> Include the contents of <file> before other files
877 C ObjC C++ ObjC++ Joined Separate
878 -iprefix <path> Specify <path> as a prefix for next two options
881 C ObjC C++ ObjC++ Joined Separate
882 -isysroot <dir> Set <dir> to be the system root directory
885 C ObjC C++ ObjC++ Joined Separate
886 -isystem <dir> Add <dir> to the start of the system include path
889 C ObjC C++ ObjC++ Joined Separate
890 -iquote <dir> Add <dir> to the end of the quote include path
893 C ObjC C++ ObjC++ Joined Separate
894 -iwithprefix <dir> Add <dir> to the end of the system include path
897 C ObjC C++ ObjC++ Joined Separate
898 -iwithprefixbefore <dir> Add <dir> to the end of the main include path
904 C ObjC C++ ObjC++ Undocumented
908 Do not search standard system include directories (those specified with -isystem will still be used)
912 Do not search standard system include directories for C++
915 C ObjC C++ ObjC++ Joined Separate
916 ; Documented in common.opt
920 ; Documented in common.opt
924 ; Documented in common.opt
926 print-objc-runtime-info
928 Generate C header of platform-specific features
932 Print a checksum of the executable for PCH validity checking, and stop
936 Remap file names when including files
940 Conform to the ISO 1998 C++ standard
944 Conform to the ISO 1998 C++ standard, with extensions that are likely to
945 become a part of the upcoming ISO C++ standard, dubbed C++0x. Note that the
946 extensions enabled by this mode are experimental and may be removed in
947 future releases of GCC.
951 Conform to the ISO 1990 C standard
955 Conform to the ISO 1999 C standard
959 Deprecated in favor of -std=c99
963 Conform to the ISO 1998 C++ standard with GNU extensions
967 Conform to the ISO 1998 C++ standard, with GNU extensions and
968 extensions that are likely to become a part of the upcoming ISO C++
969 standard, dubbed C++0x. Note that the extensions enabled by this mode
970 are experimental and may be removed in future releases of GCC.
974 Conform to the ISO 1990 C standard with GNU extensions
978 Conform to the ISO 1999 C standard with GNU extensions
982 Deprecated in favor of -std=gnu99
986 Conform to the ISO 1990 C standard
990 Conform to the ISO 1990 C standard as amended in 1994
994 Conform to the ISO 1999 C standard
998 Deprecated in favor of -std=iso9899:1999
1002 Enable traditional preprocessing
1006 -trigraphs Support ISO C trigraphs
1010 Do not predefine system-specific and GCC-specific macros
1013 Common C ObjC C++ ObjC++
1014 Enable verbose output
1018 ; Documented in common.opt
1020 ; This comment is to ensure we retain the blank line above.