diff --git a/PyIlmBase/PyImath/PyImathMathExc.h b/PyIlmBase/PyImath/PyImathMathExc.h
index f3aadac97d..9dfe1620f5 100644
--- a/PyIlmBase/PyImath/PyImathMathExc.h
+++ b/PyIlmBase/PyImath/PyImathMathExc.h
@@ -36,6 +36,7 @@
 #define _PyImathMathExc_h_
 
 #include <IexMathFloatExc.h>
+#include <PyIlmBaseConfigInternal.h>
 
 #ifdef PYIMATH_ENABLE_EXCEPTIONS
 # define MATH_EXC_ON IEX_NAMESPACE::MathExcOn mathexcon (IEX_NAMESPACE::IEEE_OVERFLOW | \