diff --git a/polymer/eduke32/source/jmact/mathutil.h b/polymer/eduke32/source/jmact/mathutil.h
index 21386c76f..b4aafa7d4 100644
--- a/polymer/eduke32/source/jmact/mathutil.h
+++ b/polymer/eduke32/source/jmact/mathutil.h
@@ -26,9 +26,15 @@ Prepared for public release: 03/21/2003 - Charlie Wiederhold, 3D Realms
 */
 //-------------------------------------------------------------------------
 
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 extern int32_t FindDistance2D(int32_t dx, int32_t dy);
 extern int32_t FindDistance3D(int32_t dx, int32_t dy, int32_t dz);
 extern int32_t FindDistance3D_HP(int32_t dx, int32_t dy, int32_t dz);
 extern int32_t ArcTangentAppx(int32_t dx, int32_t dy);
 
+#ifdef __cplusplus
+}
+#endif