diff --git a/src/gui/text/qfontengine.cpp b/src/gui/text/qfontengine.cpp
index 0b517fbf29..b2a7a8e91f 100644
--- a/src/gui/text/qfontengine.cpp
+++ b/src/gui/text/qfontengine.cpp
@@ -2105,4 +2105,8 @@ QFontEngine* QFontEngineMultiBasicImpl::createMultiFontEngine(QFontEngine *fe, i
     return engine;
 }
 
+QTestFontEngine::QTestFontEngine(int size)
+    : QFontEngineBox(TestFontEngine, size)
+{}
+
 QT_END_NAMESPACE
diff --git a/src/gui/text/qfontengine_p.h b/src/gui/text/qfontengine_p.h
index 50b1bb9e9d..9364b82bed 100644
--- a/src/gui/text/qfontengine_p.h
+++ b/src/gui/text/qfontengine_p.h
@@ -463,7 +463,7 @@ private:
 class QTestFontEngine : public QFontEngineBox
 {
 public:
-    inline QTestFontEngine(int size) : QFontEngineBox(TestFontEngine, size) {}
+    QTestFontEngine(int size);
 };
 
 QT_END_NAMESPACE