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])
])
