diff --git a/mysys/my_pthread.c b/mysys/my_pthread.c
index d8182b67442..aba3e47d754 100644
--- a/mysys/my_pthread.c
+++ b/mysys/my_pthread.c
@@ -29,7 +29,7 @@
 #define SCHED_POLICY SCHED_OTHER
 #endif
 
-uint thd_lib_detected;
+uint thd_lib_detected= 0;
 
 #ifndef my_pthread_setprio
 void my_pthread_setprio(pthread_t thread_id,int prior)