diff options
Diffstat (limited to 'build-aux/snippet')
| -rw-r--r-- | build-aux/snippet/link-warning.h | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/build-aux/snippet/link-warning.h b/build-aux/snippet/link-warning.h new file mode 100644 index 0000000000..84708ffdc6 --- /dev/null +++ b/build-aux/snippet/link-warning.h @@ -0,0 +1,49 @@ +/* A C macro for emitting link time warnings. + Copyright (C) 1995, 1997, 2000, 2002-2003, 2007, 2009-2011 Free Software + Foundation, Inc. + + This program is free software: you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published + by the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#if @HAVE_FEATURES_H@ +# include <features.h> /* for __GLIBC__, __UCLIBC__ */ +#endif + +/* GL_LINK_WARNING("literal string") arranges to emit the literal string as + a linker warning on most glibc systems. + We use a linker warning rather than a preprocessor warning, because + #warning cannot be used inside macros. */ +#ifndef GL_LINK_WARNING + /* This works on platforms with GNU ld and ELF object format. + Testing __GLIBC__ is sufficient for asserting that GNU ld is in use. + Testing __ELF__ guarantees the ELF object format. + Testing __GNUC__ is necessary for the compound expression syntax. */ +# if (defined __GLIBC__ || defined __UCLIBC__) && defined __ELF__ && defined __GNUC__ +# define GL_LINK_WARNING(message) \ + GL_LINK_WARNING1 (__FILE__, __LINE__, message) +# define GL_LINK_WARNING1(file, line, message) \ + GL_LINK_WARNING2 (file, line, message) /* macroexpand file and line */ +# define GL_LINK_WARNING2(file, line, message) \ + GL_LINK_WARNING3 (file ":" #line ": warning: " message) +# define GL_LINK_WARNING3(message) \ + ({ static const char warning[sizeof (message)] \ + __attribute__ ((__unused__, \ + __section__ (".gnu.warning"), \ + __aligned__ (1))) \ + = message "\n"; \ + (void)0; \ + }) +# else +# define GL_LINK_WARNING(message) ((void) 0) +# endif +#endif |