diff --git a/pkgs/stdenv/adapters.nix b/pkgs/stdenv/adapters.nix
index 9931445ce561..977ef2eef9c7 100644
--- a/pkgs/stdenv/adapters.nix
+++ b/pkgs/stdenv/adapters.nix
@@ -328,7 +328,7 @@ rec {
 
       mapRuntimeToSDK = pkg:
         # Only remap xcbuild for now, which exports the SDK used to build it.
-        if pkg != null && lib.getName pkg == "xcodebuild"
+        if pkg != null && lib.isAttrs pkg && lib.getName pkg == "xcodebuild"
           then pkg.override { stdenv = overrideSDK stdenv { inherit darwinMinVersion darwinSdkVersion; }; }
           else pkg;