diff --git a/tests/auto/corelib/text/qstring/tst_qstring.cpp b/tests/auto/corelib/text/qstring/tst_qstring.cpp
index 0d0c38d51f..8d09cfa708 100644
--- a/tests/auto/corelib/text/qstring/tst_qstring.cpp
+++ b/tests/auto/corelib/text/qstring/tst_qstring.cpp
@@ -637,7 +637,7 @@ QString verifyZeroTermination(const QString &str)
     if (!strDataPtr->isMutable())
         return str;
 
-    int strSize = str.size();
+    qsizetype strSize = str.size();
     QChar strTerminator = str.constData()[strSize];
     if (QChar('\0') != strTerminator)
         return QString::fromLatin1(