extern-inline.m4 (4247B)
1 dnl 'extern inline' a la ISO C99. 2 3 dnl Copyright 2012-2014 Free Software Foundation, Inc. 4 dnl This file is free software; the Free Software Foundation 5 dnl gives unlimited permission to copy and/or distribute it, 6 dnl with or without modifications, as long as this notice is preserved. 7 8 AC_DEFUN([gl_EXTERN_INLINE], 9 [ 10 AH_VERBATIM([extern_inline], 11 [/* Please see the Gnulib manual for how to use these macros. 12 13 Suppress extern inline with HP-UX cc, as it appears to be broken; see 14 <http://lists.gnu.org/archive/html/bug-texinfo/2013-02/msg00030.html>. 15 16 Suppress extern inline with Sun C in standards-conformance mode, as it 17 mishandles inline functions that call each other. E.g., for 'inline void f 18 (void) { } inline void g (void) { f (); }', c99 incorrectly complains 19 'reference to static identifier "f" in extern inline function'. 20 This bug was observed with Sun C 5.12 SunOS_i386 2011/11/16. 21 22 Suppress extern inline (with or without __attribute__ ((__gnu_inline__))) 23 on configurations that mistakenly use 'static inline' to implement 24 functions or macros in standard C headers like <ctype.h>. For example, 25 if isdigit is mistakenly implemented via a static inline function, 26 a program containing an extern inline function that calls isdigit 27 may not work since the C standard prohibits extern inline functions 28 from calling static functions. This bug is known to occur on: 29 30 OS X 10.8 and earlier; see: 31 http://lists.gnu.org/archive/html/bug-gnulib/2012-12/msg00023.html 32 33 DragonFly; see 34 http://muscles.dragonflybsd.org/bulk/bleeding-edge-potential/latest-per-pkg/ah-tty-0.3.12.log 35 36 FreeBSD; see: 37 http://lists.gnu.org/archive/html/bug-gnulib/2014-07/msg00104.html 38 39 OS X 10.9 has a macro __header_inline indicating the bug is fixed for C and 40 for clang but remains for g++; see <http://trac.macports.org/ticket/41033>. 41 Assume DragonFly and FreeBSD will be similar. */ 42 #if (((defined __APPLE__ && defined __MACH__) \ 43 || defined __DragonFly__ || defined __FreeBSD__) \ 44 && (defined __header_inline \ 45 ? (defined __cplusplus && defined __GNUC_STDC_INLINE__ \ 46 && ! defined __clang__) \ 47 : ((! defined _DONT_USE_CTYPE_INLINE_ \ 48 && (defined __GNUC__ || defined __cplusplus)) \ 49 || (defined _FORTIFY_SOURCE && 0 < _FORTIFY_SOURCE \ 50 && defined __GNUC__ && ! defined __cplusplus)))) 51 # define _GL_EXTERN_INLINE_STDHEADER_BUG 52 #endif 53 #if ((__GNUC__ \ 54 ? defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__ \ 55 : (199901L <= __STDC_VERSION__ \ 56 && !defined __HP_cc \ 57 && !(defined __SUNPRO_C && __STDC__))) \ 58 && !defined _GL_EXTERN_INLINE_STDHEADER_BUG) 59 # define _GL_INLINE inline 60 # define _GL_EXTERN_INLINE extern inline 61 # define _GL_EXTERN_INLINE_IN_USE 62 #elif (2 < __GNUC__ + (7 <= __GNUC_MINOR__) && !defined __STRICT_ANSI__ \ 63 && !defined _GL_EXTERN_INLINE_STDHEADER_BUG) 64 # if defined __GNUC_GNU_INLINE__ && __GNUC_GNU_INLINE__ 65 /* __gnu_inline__ suppresses a GCC 4.2 diagnostic. */ 66 # define _GL_INLINE extern inline __attribute__ ((__gnu_inline__)) 67 # else 68 # define _GL_INLINE extern inline 69 # endif 70 # define _GL_EXTERN_INLINE extern 71 # define _GL_EXTERN_INLINE_IN_USE 72 #else 73 # define _GL_INLINE static _GL_UNUSED 74 # define _GL_EXTERN_INLINE static _GL_UNUSED 75 #endif 76 77 #if 4 < __GNUC__ + (6 <= __GNUC_MINOR__) 78 # if defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__ 79 # define _GL_INLINE_HEADER_CONST_PRAGMA 80 # else 81 # define _GL_INLINE_HEADER_CONST_PRAGMA \ 82 _Pragma ("GCC diagnostic ignored \"-Wsuggest-attribute=const\"") 83 # endif 84 /* Suppress GCC's bogus "no previous prototype for 'FOO'" 85 and "no previous declaration for 'FOO'" diagnostics, 86 when FOO is an inline function in the header; see 87 <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54113>. */ 88 # define _GL_INLINE_HEADER_BEGIN \ 89 _Pragma ("GCC diagnostic push") \ 90 _Pragma ("GCC diagnostic ignored \"-Wmissing-prototypes\"") \ 91 _Pragma ("GCC diagnostic ignored \"-Wmissing-declarations\"") \ 92 _GL_INLINE_HEADER_CONST_PRAGMA 93 # define _GL_INLINE_HEADER_END \ 94 _Pragma ("GCC diagnostic pop") 95 #else 96 # define _GL_INLINE_HEADER_BEGIN 97 # define _GL_INLINE_HEADER_END 98 #endif]) 99 ])