* sysdeps/pthread/pthread.h (__PTHREAD_RWLOCK_INT_FLAGS_SHARED):
	New.
	(PTHREAD_RWLOCK_WRITER_NONRECURSIVE_INITIALIZER_NP): Check
	__PTHREAD_RWLOCK_INT_FLAGS_SHARED instead of __WORDSIZE.

diff --git a/nptl/sysdeps/pthread/pthread.h b/nptl/sysdeps/pthread/pthread.h
index fcc0ce8..88c7c25 100644
--- a/nptl/sysdeps/pthread/pthread.h
+++ b/nptl/sysdeps/pthread/pthread.h
@@ -118,11 +118,20 @@ enum
   PTHREAD_RWLOCK_DEFAULT_NP = PTHREAD_RWLOCK_PREFER_READER_NP
 };
 
+/* Define __PTHREAD_RWLOCK_INT_FLAGS_SHARED to 1 if pthread_rwlock_t
+   has the shared field.  All 64-bit architectures have the shared field
+   in pthread_rwlock_t.  */
+#ifndef __PTHREAD_RWLOCK_INT_FLAGS_SHARED
+# if __WORDSIZE == 64
+#  define __PTHREAD_RWLOCK_INT_FLAGS_SHARED 1
+# endif
+#endif
+
 /* Read-write lock initializers.  */
 # define PTHREAD_RWLOCK_INITIALIZER \
   { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 } }
 # ifdef __USE_GNU
-#  if __WORDSIZE == 64
+#  ifdef __PTHREAD_RWLOCK_INT_FLAGS_SHARED
 #   define PTHREAD_RWLOCK_WRITER_NONRECURSIVE_INITIALIZER_NP \
   { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,					      \
 	PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP } }