diff --git a/pkgs/tools/security/gnupg/24.nix b/pkgs/tools/security/gnupg/24.nix
index f4c7b56d5d1e..80776bb58ab4 100644
--- a/pkgs/tools/security/gnupg/24.nix
+++ b/pkgs/tools/security/gnupg/24.nix
@@ -110,7 +110,7 @@ stdenv.mkDerivation rec {
       sed -i 's,"libpcsclite\.so[^"]*","${lib.getLib pcsclite}/lib/libpcsclite.so",g' scd/scdaemon.c
     '';
 
-  NIX_CFLAGS_COMPILE = lib.optionalString stdenv.hostPlatform.isDarwin "-Wno-implicit-function-declaration";
+  env.NIX_CFLAGS_COMPILE = lib.optionalString stdenv.hostPlatform.isDarwin "-Wno-implicit-function-declaration";
 
   configureFlags =
     [