diff --git a/src/msw/fontutil.cpp b/src/msw/fontutil.cpp
index 9b61937b17..dc7d1bd496 100644
--- a/src/msw/fontutil.cpp
+++ b/src/msw/fontutil.cpp
@@ -202,7 +202,7 @@ bool wxTestFontEncoding(const wxNativeEncodingInfo& info)
     wxZeroMemory(lf);       // all default values
 
     lf.lfCharSet = info.charset;
-    wxStrncpy(lf.lfFaceName, info.facename, sizeof(lf.lfFaceName));
+    wxStrncpy(lf.lfFaceName, info.facename, WXSIZEOF(lf.lfFaceName));
 
     HFONT hfont = ::CreateFontIndirect(&lf);
     if ( !hfont )