/* 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 __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
