Fix typo to do with rwlock aliasing.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@177 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/vg_libpthread.c b/vg_libpthread.c
index 4f0bf99..beaeea5 100644
--- a/vg_libpthread.c
+++ b/vg_libpthread.c
@@ -1422,7 +1422,7 @@
    return 0;
 }
 
-weak_alias(pthread_rwlock_wrlock, __pthread_wrlock_unlock)
+weak_alias(pthread_rwlock_wrlock, __pthread_rwlock_wrlock)
 
 
 /* I've no idea what these are, but they get called quite a lot.