Fix compilation problem on Linux

diff --git a/samples/qt/Common/src/DocumentCommon.cxx b/samples/qt/Common/src/DocumentCommon.cxx
index 64d428ca084c9a99aa8498edf1a1d6f42a3a1579..f23e2d4c6d041d74e3fd651982ee49f15b73f46d 100755 (executable)
--- a/samples/qt/Common/src/DocumentCommon.cxx
+++ b/samples/qt/Common/src/DocumentCommon.cxx
@@ -16,7 +16,7 @@
 #include <OpenGl_GraphicDriver.hxx>
 #include <TCollection_AsciiString.hxx>
 
-Handle(V3d_Viewer) DocumentCommon::Viewer( const Standard_CString /*aDisplay*/,
+Handle(V3d_Viewer) DocumentCommon::Viewer( const Standard_CString aDisplay,
                                                     const Standard_ExtString aName,
                                                     const Standard_CString aDomain,
                                                     const Standard_Real ViewSize,
@@ -31,6 +31,8 @@ Handle(V3d_Viewer) DocumentCommon::Viewer( const Standard_CString /*aDisplay*/,
     Handle(Aspect_DisplayConnection) aDisplayConnection;
 #if !defined(_WIN32) && !defined(__WIN32__) && (!defined(__APPLE__) || defined(MACOSX_USE_GLX))
     aDisplayConnection = new Aspect_DisplayConnection (aDisplay);
+#else
+    (void)aDisplay; // avoid compiler warning on unused argument
 #endif
     aGraphicDriver = new OpenGl_GraphicDriver (aDisplayConnection);
   }