diff --git a/pkgs/games/cataclysm-dda/default.nix b/pkgs/games/cataclysm-dda/default.nix
index a3adec38401..01829238daa 100644
--- a/pkgs/games/cataclysm-dda/default.nix
+++ b/pkgs/games/cataclysm-dda/default.nix
@@ -46,6 +46,8 @@ stdenv.mkDerivation rec {
     "WARNINGS+=-Wno-inconsistent-missing-override"
   ];
 
+  NIX_CFLAGS_COMPILE = stdenv.lib.optionalString stdenv.cc.isClang "-Wno-user-defined-warnings";
+
   postBuild = stdenv.lib.optionalString (tiles && stdenv.isDarwin) ''
     # iconutil on macOS is not available in nixpkgs
     png2icns data/osx/AppIcon.icns data/osx/AppIcon.iconset/*