diff --git a/pkgs/development/libraries/freeimage/default.nix b/pkgs/development/libraries/freeimage/default.nix
index 5714131416d6..b50783e2719e 100644
--- a/pkgs/development/libraries/freeimage/default.nix
+++ b/pkgs/development/libraries/freeimage/default.nix
@@ -29,6 +29,10 @@ stdenv.mkDerivation {
 
   preInstall = ''
     mkdir -p $INCDIR $INSTALLDIR
+  ''
+  # Workaround for Makefiles.osx not using ?=
+  + lib.optionalString stdenv.isDarwin ''
+    makeFlagsArray+=( "INCDIR=$INCDIR" "INSTALLDIR=$INSTALLDIR" )
   '';
 
   postInstall = lib.optionalString (!stdenv.isDarwin) ''