diff --git a/pkgs/development/compilers/llvm/16/compiler-rt/default.nix b/pkgs/development/compilers/llvm/16/compiler-rt/default.nix
index 3666f291c321..d608d66f40db 100644
--- a/pkgs/development/compilers/llvm/16/compiler-rt/default.nix
+++ b/pkgs/development/compilers/llvm/16/compiler-rt/default.nix
@@ -31,7 +31,7 @@ stdenv.mkDerivation {
     ++ lib.optional stdenv.isDarwin xcbuild.xcrun;
   buildInputs = lib.optional stdenv.hostPlatform.isDarwin libcxxabi;
 
-  env.NIX_CFLAGS_COMPILE = toString [
+  NIX_CFLAGS_COMPILE = [
     "-DSCUDO_DEFAULT_OPTIONS=DeleteSizeMismatch=0:DeallocationTypeMismatch=0"
   ];