diff --git a/lib/isc/pthreads/mutex.c b/lib/isc/pthreads/mutex.c
index 71e843c159..2a502a5f51 100644
--- a/lib/isc/pthreads/mutex.c
+++ b/lib/isc/pthreads/mutex.c
@@ -231,13 +231,6 @@ static isc_boolean_t errcheck_initialized = ISC_FALSE;
 static pthread_mutexattr_t errcheck;
 static isc_once_t once_errcheck = ISC_ONCE_INIT;
 
-static void
-destroy_errcheck(void) {
-	if (errcheck_initialized) {
-		RUNTIME_CHECK(pthread_mutexattr_destroy(&errcheck) == 0);
-	}
-}
-
 static void
 initialize_errcheck(void) {
 	RUNTIME_CHECK(pthread_mutexattr_init(&errcheck) == 0);
@@ -274,13 +267,6 @@ static isc_boolean_t attr_initialized = ISC_FALSE;
 static pthread_mutexattr_t attr;
 static isc_once_t once_attr = ISC_ONCE_INIT;
 
-static void
-destroy_attr(void) {
-	if (attr_initialized) {
-		RUNTIME_CHECK(pthread_mutexattr_destroy(&attr) == 0);
-	}
-}
-
 #ifdef HAVE_PTHREAD_MUTEX_ADAPTIVE_NP
 static void
 initialize_attr(void) {