diff --git a/ThirdParty/freetype/vtk_freetype.h.in b/ThirdParty/freetype/vtk_freetype.h.in
index c3f6f4f3..fd525e55 100644
--- a/ThirdParty/freetype/vtk_freetype.h.in
+++ b/ThirdParty/freetype/vtk_freetype.h.in
@@ -20,6 +20,13 @@
 
 #ifdef VTK_USE_SYSTEM_FREETYPE
 # include <ft2build.h>
+#ifndef FT_CALLBACK_DEF
+#ifdef __cplusplus
+#define FT_CALLBACK_DEF( x )  extern "C"  x
+#else
+#define FT_CALLBACK_DEF( x )  static  x
+#endif
+#endif /* FT_CALLBACK_DEF */
 #else
 # include <vtkfreetype/include/ft2build.h>
 #endif