diff --git a/src/corelib/tools/qcryptographichash.h b/src/corelib/tools/qcryptographichash.h
index 2bfc03373ab..6ebe389faf5 100644
--- a/src/corelib/tools/qcryptographichash.h
+++ b/src/corelib/tools/qcryptographichash.h
@@ -65,7 +65,7 @@ public:
         Sha512
     };
 
-    QCryptographicHash(Algorithm method);
+    explicit QCryptographicHash(Algorithm method);
     ~QCryptographicHash();
 
     void reset();