diff --git a/src_ext/patches/mccs/build-on-darwin.patch b/src_ext/patches/mccs/build-on-darwin.patch
new file mode 100644
index 00000000..157e2094
--- /dev/null
+++ b/src_ext/patches/mccs/build-on-darwin.patch
@@ -0,0 +1,12 @@
+diff --git a/src/context_flags.ml b/src/context_flags.ml
+index 7470030..6e07370 100644
+--- a/src/context_flags.ml
++++ b/src/context_flags.ml
+@@ -24,6 +24,7 @@ let ifc c x = if c then x else []
+ 
+ let cxxflags =
+   let flags =
++    (ifc (Config.system = "macosx") ["-x"; "c++"]) @
+     (ifc (Sys.win32 && Config.ccomp_type = "msvc") ["/EHsc"]) @
+     (ifc useGLPK ["-DUSEGLPK"]) @
+     (ifc useCOIN ["-DUSECOIN"]) @