diff --git a/pkgs/games/dwarf-fortress/dfhack/default.nix b/pkgs/games/dwarf-fortress/dfhack/default.nix
index f54a0e1511dfc..914ccbb6ab334 100644
--- a/pkgs/games/dwarf-fortress/dfhack/default.nix
+++ b/pkgs/games/dwarf-fortress/dfhack/default.nix
@@ -125,7 +125,7 @@ in
     });
 
     # gcc 11 fix
-    NIX_CFLAGS_COMPILE = lib.optionalString (lib.versionOlder version "0.47.05-r3") "-fpermissive";
+    CXXFLAGS = lib.optionalString (lib.versionOlder version "0.47.05-r3") "-fpermissive";
 
     # As of
     # https://github.com/DFHack/dfhack/commit/56e43a0dde023c5a4595a22b29d800153b31e3c4,