name : extern-inline.m4 dnl 'extern inline' a la ISO C99. dnl Copyright 2012-2016 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, dnl with or without modifications, as long as this notice is preserved. AC_DEFUN([gl_EXTERN_INLINE], [ AH_VERBATIM([extern_inline], [/* Please see the Gnulib manual for how to use these macros. Suppress extern inline with HP-UX cc, as it appears to be broken; see <http://lists.gnu.org/archive/html/bug-texinfo/2013-02/msg00030.html>. Suppress extern inline with Sun C in standards-conformance mode, as it mishandles inline functions that call each other. E.g., for 'inline void f (void) { } inline void g (void) { f (); }', c99 incorrectly complains 'reference to static identifier "f" in extern inline function'. This bug was observed with Sun C 5.12 SunOS_i386 2011/11/16. Suppress extern inline (with or without __attribute__ ((__gnu_inline__))) on configurations that mistakenly use 'static inline' to implement functions or macros in standard C headers like <ctype.h>. For example, if isdigit is mistakenly implemented via a static inline function, a program containing an extern inline function that calls isdigit may not work since the C standard prohibits extern inline functions from calling static functions. This bug is known to occur on: OS X 10.8 and earlier; see: http://lists.gnu.org/archive/html/bug-gnulib/2012-12/msg00023.html DragonFly; see http://muscles.dragonflybsd.org/bulk/bleeding-edge-potential/latest-per-pkg/ah-tty-0.3.12.log FreeBSD; see: http://lists.gnu.org/archive/html/bug-gnulib/2014-07/msg00104.html OS X 10.9 has a macro __header_inline indicating the bug is fixed for C and for clang but remains for g++; see <http://trac.macports.org/ticket/41033>. Assume DragonFly and FreeBSD will be similar. */ #if (((defined __APPLE__ && defined __MACH__) \ || defined __DragonFly__ || defined __FreeBSD__) \ && (defined __header_inline \ ? (defined __cplusplus && defined __GNUC_STDC_INLINE__ \ && ! defined __clang__) \ : ((! defined _DONT_USE_CTYPE_INLINE_ \ && (defined __GNUC__ || defined __cplusplus)) \ || (defined _FORTIFY_SOURCE && 0 < _FORTIFY_SOURCE \ && defined __GNUC__ && ! defined __cplusplus)))) # define _GL_EXTERN_INLINE_STDHEADER_BUG #endif #if ((__GNUC__ \ ? defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__ \ : (199901L <= __STDC_VERSION__ \ && !defined __HP_cc \ && !defined __PGI \ && !(defined __SUNPRO_C && __STDC__))) \ && !defined _GL_EXTERN_INLINE_STDHEADER_BUG) # define _GL_INLINE inline # define _GL_EXTERN_INLINE extern inline # define _GL_EXTERN_INLINE_IN_USE #elif (2 < __GNUC__ + (7 <= __GNUC_MINOR__) && !defined __STRICT_ANSI__ \ && !defined _GL_EXTERN_INLINE_STDHEADER_BUG) # if defined __GNUC_GNU_INLINE__ && __GNUC_GNU_INLINE__ /* __gnu_inline__ suppresses a GCC 4.2 diagnostic. */ # define _GL_INLINE extern inline __attribute__ ((__gnu_inline__)) # else # define _GL_INLINE extern inline # endif # define _GL_EXTERN_INLINE extern # define _GL_EXTERN_INLINE_IN_USE #else # define _GL_INLINE static _GL_UNUSED # define _GL_EXTERN_INLINE static _GL_UNUSED #endif /* In GCC 4.6 (inclusive) to 5.1 (exclusive), suppress bogus "no previous prototype for 'FOO'" and "no previous declaration for 'FOO'" diagnostics, when FOO is an inline function in the header; see <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54113> and <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63877>. */ #if __GNUC__ == 4 && 6 <= __GNUC_MINOR__ # if defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__ # define _GL_INLINE_HEADER_CONST_PRAGMA # else # define _GL_INLINE_HEADER_CONST_PRAGMA \ _Pragma ("GCC diagnostic ignored \"-Wsuggest-attribute=const\"") # endif # define _GL_INLINE_HEADER_BEGIN \ _Pragma ("GCC diagnostic push") \ _Pragma ("GCC diagnostic ignored \"-Wmissing-prototypes\"") \ _Pragma ("GCC diagnostic ignored \"-Wmissing-declarations\"") \ _GL_INLINE_HEADER_CONST_PRAGMA # define _GL_INLINE_HEADER_END \ _Pragma ("GCC diagnostic pop") #else # define _GL_INLINE_HEADER_BEGIN # define _GL_INLINE_HEADER_END #endif]) ])