diff --git a/configure.ac b/configure.ac
index f96d2d5421..2de7d76f77 100644
--- a/configure.ac
+++ b/configure.ac
@@ -553,14 +553,15 @@ LIBS="$PTHREAD_LIBS $LIBS"
 CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
 CC="$PTHREAD_CC"
 
-AC_CHECK_FUNCS([pthread_attr_getstacksize pthread_attr_setstacksize pthread_barrier_init pthread_spin_init])
+AC_MSG_CHECKING([for PTHREAD_MUTEX_ADAPTIVE_NP])
+AC_COMPILE_IFELSE(
+  [AC_LANG_PROGRAM([[#include <pthread.h>]],
+		   [[(void)pthread_mutexattr_settype(&(pthread_mutexattr_t){ NULL }, PTHREAD_MUTEX_ADAPTIVE_NP);]])],
+  [AC_MSG_RESULT([yes])
+   AC_DEFINE([HAVE_PTHREAD_MUTEX_ADAPTIVE_NP], [1], [Define to 1 if PTHREAD_MUTEX_ADAPTIVE_NP is available])],
+  [AC_MSG_RESULT([no])])
 
-# [pairwise: --with-locktype=adaptive, --with-locktype=standard]
-AC_ARG_WITH([locktype],
-	    AS_HELP_STRING([--with-locktype=ARG],
-			   [Specify mutex lock type
-			    (adaptive or standard)]),
-	    [], [with_locktype="adaptive"])
+AC_CHECK_FUNCS([pthread_attr_getstacksize pthread_attr_setstacksize pthread_barrier_init pthread_spin_init])
 
 AC_CHECK_HEADERS([sched.h])
 
@@ -1712,9 +1713,6 @@ report() {
     if test "yes" = "$enable_full_report" -o "rbt" = "$zonedb"; then
             echo "    Default cache database type: $cachedb"
     fi
-    if test "yes" = "$enable_full_report" -o "standard" = "$with_locktype"; then
-	echo "    Mutex lock type: $with_locktype"
-    fi
     test "no" = "$enable_dnstap" || \
 	    echo "    Allow 'dnstap' packet logging (--enable-dnstap)"
     test -z "$MAXMINDDB_LIBS" || echo "    GeoIP2 access control (--enable-geoip)"
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
 
 /*
diff --git a/lib/isc/mutex.c b/lib/isc/mutex.c
index 67815eb7e9..e31ba1339c 100644
--- a/lib/isc/mutex.c
+++ b/lib/isc/mutex.c
@@ -33,15 +33,14 @@ static isc_once_t init_once = ISC_ONCE_INIT;
 static void
 mutex_initialize(void) {
 	RUNTIME_CHECK(pthread_mutexattr_init(&isc__mutex_init_attr) == 0);
-#if ISC_MUTEX_ERROR_CHECK && defined(PTHREAD_MUTEX_ERRORCHECK_NP)
+#if ISC_MUTEX_ERROR_CHECK
 	RUNTIME_CHECK(pthread_mutexattr_settype(&isc__mutex_init_attr,
-						PTHREAD_MUTEX_ERRORCHECK_NP) ==
-		      0);
-#elif defined(PTHREAD_MUTEX_ADAPTIVE_NP)
+						PTHREAD_MUTEX_ERRORCHECK) == 0);
+#elif HAVE_PTHREAD_MUTEX_ADAPTIVE_NP
 	RUNTIME_CHECK(pthread_mutexattr_settype(&isc__mutex_init_attr,
 						PTHREAD_MUTEX_ADAPTIVE_NP) ==
 		      0);
-#endif /* HAVE_PTHREAD_MUTEX_ADAPTIVE_NP */
+#endif
 }
 
 void