nixpkgs

3bdc867a - stdenv, trivial-builders: replace `// optionalAttrs` with nullable attr names

stdenv, trivial-builders: replace `// optionalAttrs` with nullable attr names Follow-up to #430969. Replace remaining `// optionalAttrs` patterns with `${if cond then "name" else null} = value;` to avoid per-derivation closure allocations and `//` merge operations. Changes: - make-derivation.nix: inline Darwin, Windows, outputChecks blocks and the `env'`/`__structuredAttrs` patterns in mkDerivationSimple - trivial-builders: inline optionalAttrs in runCommandWith and symlinkJoin