fix detection of mbstate_t with clang

AC_TRY_COMPILE expexts a function body

diff --git a/ext/standard/config.m4 b/ext/standard/config.m4
index e2ce61f56115d68059b261b8c153c2d1b5a2210c..c502c5426892ae68d8e55eeef7cbbf49f309d8f8 100644 (file)
--- a/ext/standard/config.m4
+++ b/ext/standard/config.m4
@@ -577,7 +577,7 @@ AC_TRY_COMPILE([
 # include <wchar.h>
 #endif
 ],[
-int __tmp__() { mbstate_t a; }
+mbstate_t a;
 ],[
   ac_cv_type_mbstate_t=yes
 ],[