diff --git a/pkgs/stdenv/generic/check-meta.nix b/pkgs/stdenv/generic/check-meta.nix
index 1a3e65ea650d7..6caed4b8bb24f 100644
--- a/pkgs/stdenv/generic/check-meta.nix
+++ b/pkgs/stdenv/generic/check-meta.nix
@@ -677,7 +677,7 @@ let
           defaultCPEParts = {
             part = "a";
             #vendor = null;
-            ${if attrs ? pname then "product" else null} = attrs.pname;
+            ${if attrs.pname or null != null then "product" else null} = attrs.pname;
             #version = null;
             #update = null;
             edition = "*";