diff --git a/wxPython/contrib/glcanvas/mac/glcanvas.cpp b/wxPython/contrib/glcanvas/mac/glcanvas.cpp
index 2c6151345e..3294ba8891 100644
--- a/wxPython/contrib/glcanvas/mac/glcanvas.cpp
+++ b/wxPython/contrib/glcanvas/mac/glcanvas.cpp
@@ -55,6 +55,11 @@ extern PyObject *SWIG_newvarlink(void);
 #define SWIG_name    "glcanvasc"
 
 #include "wxPython.h"
+
+#ifdef __WXMAC__  // avoid a bug in Carbon headers
+#define scalb scalbn
+#endif
+
 #ifdef __WXMSW__
 #include "myglcanvas.h"
 #else