diff --git a/pkgs/development/tools/xcbuild/default.nix b/pkgs/development/tools/xcbuild/default.nix
index 0fc56827de83..f2be61bd2139 100644
--- a/pkgs/development/tools/xcbuild/default.nix
+++ b/pkgs/development/tools/xcbuild/default.nix
@@ -32,7 +32,7 @@ in stdenv.mkDerivation rec {
   '';
 
   # Avoid a glibc >= 2.25 deprecation warning that gets fatal via -Werror.
-  postPatch = ''
+  postPatch = stdenv.lib.optionalString (!stdenv.isDarwin) ''
     sed 1i'#include <sys/sysmacros.h>' \
       -i Libraries/xcassets/Headers/xcassets/Slot/SystemVersion.h
   '';