diff --git a/src/msw/datetimectrl.cpp b/src/msw/datetimectrl.cpp
index 35ad786034..dffbee1802 100644
--- a/src/msw/datetimectrl.cpp
+++ b/src/msw/datetimectrl.cpp
@@ -121,10 +121,14 @@ void wxDateTimePickerCtrl::MSWUpdateFormat(bool valid)
     // as the control seems to remember whichever format was used when it was
     // created, i.e. this works both with and without wxDP_SHOWCENTURY.
 
-    // Note: due to a bug in MinGW headers, with missing parentheses around the
-    // macro argument (corrected in or before 8.2, but still existing in 5.3),
-    // we have to use a temporary variable here.
-    const TCHAR* const format = valid ? NULL : m_nullText.t_str();
+    // Use a temporary variable to ensure that the code compiles in
+    // wxUSE_UNICODE_UTF8 case, where t_str() doesn't return a pointer.
+    const TCHAR* format;
+    if ( valid )
+        format = NULL;
+    else
+        format = m_nullText.t_str();
+
     DateTime_SetFormat(GetHwnd(), format);
 }