| /* A C macro for emitting link time warnings. |
| Copyright (C) 1995, 1997, 2000, 2002-2003, 2007, 2009-2020 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 <https://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 |
