diff --git a/pkgs/games/dwarf-fortress/dfhack/default.nix b/pkgs/games/dwarf-fortress/dfhack/default.nix
index 23bf1b462982..1bd3a49945c9 100644
--- a/pkgs/games/dwarf-fortress/dfhack/default.nix
+++ b/pkgs/games/dwarf-fortress/dfhack/default.nix
@@ -145,8 +145,19 @@ stdenv.mkDerivation {
     # Use SDL_GetPrefPath since this takes XDG_DATA_HOME into account (which is correct).
     ++ optional (versionAtLeast version "52.02-r2") ./use-df-linux-dir.patch;
 
-  # gcc 11 fix
-  CXXFLAGS = optionalString (versionOlder version "0.47.05-r3") "-fpermissive";
+  env = {
+    # gcc 11 fix
+    CXXFLAGS = optionalString (versionOlder version "0.47.05-r3") "-fpermissive";
+
+    NIX_CFLAGS_COMPILE = toString (
+      [
+        "-Wno-error=deprecated-enum-enum-conversion"
+      ]
+      ++ optionals (versionOlder version "0.47") [
+        "-fpermissive"
+      ]
+    );
+  };
 
   nativeBuildInputs = [
     cmake
@@ -200,11 +211,6 @@ stdenv.mkDerivation {
     "-DCMAKE_PROJECT_TOP_LEVEL_INCLUDES=${fetchOverrides}"
   ];
 
-  NIX_CFLAGS_COMPILE = [
-    "-Wno-error=deprecated-enum-enum-conversion"
-  ]
-  ++ optionals (versionOlder version "0.47") [ "-fpermissive" ];
-
   preFixup = ''
     # Wrap dfhack scripts.
     if [ -f $out/dfhack ]; then