Mac OS X does not support comparing a mutex to its initializer. Create a test for this.

git-svn-id: http://svn.digium.com/svn/asterisk/trunk@256370 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 14 insertions, 0 deletions

diff --git a/configure.ac b/configure.ac
index 057327a09..7a4cbb8eb 100644
--- a/configure.ac
+++ b/configure.ac
@@ -595,6 +595,20 @@ fi
 
 AST_C_DEFINE_CHECK([PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP], [PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP], [pthread.h])
 
+# Can we compare a mutex to its initial value?
+# Generally yes on OpenBSD/FreeBSD and no on Mac OS X.
+AC_MSG_CHECKING(whether we can compare a mutex to its initial value)
+AC_LINK_IFELSE(
+	AC_LANG_PROGRAM([#include <pthread.h>], [pthread_mutex_t lock;
+	if ((lock) != ((pthread_mutex_t) PTHREAD_MUTEX_INITIALIZER)) {
+		return 0;
+	}
+	return 0]),
+	AC_MSG_RESULT(yes)
+	AC_DEFINE([CAN_COMPARE_MUTEX_TO_INIT_VALUE], 1, [Define to 1 if your system's implementation of mutexes supports comparison of a mutex to its initializer.]),
+	AC_MSG_RESULT(no)
+)
+
 #if test "${cross_compiling}" = "no";
 #then
 #AC_MSG_CHECKING(for working epoll support)