diff --git a/pkgs/applications/graphics/gnuclad/default.nix b/pkgs/applications/graphics/gnuclad/default.nix
index a1b4accc8d59..0ac22106b989 100644
--- a/pkgs/applications/graphics/gnuclad/default.nix
+++ b/pkgs/applications/graphics/gnuclad/default.nix
@@ -10,7 +10,7 @@ stdenv.mkDerivation rec {
     sha256 = "0ka2kscpjff7gflsargv3r9fdaxhkf3nym9mfaln3pnq6q7fwdki";
   };
 
-  NIX_CFLAGS_COMPILE = "-Wno-error=catch-value";
+  NIX_CFLAGS_COMPILE = lib.optional stdenv.cc.isGNU "-Wno-error=catch-value";
 
   nativeBuildInputs = [ pkg-config ];
 
@@ -19,6 +19,6 @@ stdenv.mkDerivation rec {
     description = "gnuclad tries to help the environment by creating trees.  Its primary use will be generating cladogram trees for the GNU/Linux distro timeline project";
     license = licenses.gpl3Plus;
     maintainers = with maintainers; [ mog ];
-    platforms = platforms.linux;
+    platforms = platforms.unix;
   };
 }