diff --git a/tests/shared/localechange.h b/tests/shared/localechange.h
index 2c642471667..0e27fd297bd 100644
--- a/tests/shared/localechange.h
+++ b/tests/shared/localechange.h
@@ -12,7 +12,7 @@
 
 namespace QTestLocaleChange {
 
-    QLocale resetSystemLocale()
+    inline QLocale resetSystemLocale()
     {
 #ifndef QT_NO_SYSTEMLOCALE
         { // Transient instance marks system locale data as stale: