diff --git a/lib/isc/include/isc/mutex.h b/lib/isc/include/isc/mutex.h
index 341148a753..df24922336 100644
--- a/lib/isc/include/isc/mutex.h
+++ b/lib/isc/include/isc/mutex.h
@@ -23,14 +23,6 @@
 #include <isc/result.h> /* for ISC_R_ codes */
 #include <isc/util.h>
 
-#if ISC_MUTEX_ERROR_CHECK && defined(PTHREAD_ERRORCHECK_MUTEX_INITIALIZER_NP)
-#define ISC_MUTEX_INITIALIZER PTHREAD_ERRORCHECK_MUTEX_INITIALIZER_NP
-#elif defined(PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP)
-#define ISC_MUTEX_INITIALIZER PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP
-#else
-#define ISC_MUTEX_INITIALIZER PTHREAD_MUTEX_INITIALIZER
-#endif
-
 ISC_LANG_BEGINDECLS
 
 /*