threads: use forward declarations only for glibc
Fixes bug #704908
The declarations of pthread functions, used to generate weak references
to them, fail to suppress macros. Thus, if any pthread function has
been provided as a macro, compiling threads.c will fail.
This breaks on musl libc, which defines pthread_equal as a macro (in
addition to providing the function, as required).
Prevent the declarations for e.g. musl libc by refining the condition.
The idea for this solution was borrowed from the alpine linux guys, see
http://git.alpinelinux.org/cgit/aports/tree/main/libxml2/libxml2-pthread.patch
Signed-off-by: Michael Heimpold <mhei@heimpold.de>
diff --git a/threads.c b/threads.c
index 8921204..78006a2 100644
--- a/threads.c
+++ b/threads.c
@@ -47,7 +47,7 @@
#ifdef HAVE_PTHREAD_H
static int libxml_is_threaded = -1;
-#ifdef __GNUC__
+#if defined(__GNUC__) && defined(__GLIBC__)
#ifdef linux
#if (__GNUC__ == 3 && __GNUC_MINOR__ >= 3) || (__GNUC__ > 3)
extern int pthread_once (pthread_once_t *__once_control,
@@ -89,7 +89,7 @@
__attribute((weak));
#endif
#endif /* linux */
-#endif /* __GNUC__ */
+#endif /* defined(__GNUC__) && defined(__GLIBC__) */
#endif /* HAVE_PTHREAD_H */
/*