Revert "shellFor: Don't suck in src to compare to deps. [Fixes #51079]"

[infinisil]

Reverts #54900

Apparently has some problems: #54901 (comment)

[ElvishJerricco]

How can I test that failure?

[ElvishJerricco]

Looks like there are some Haskell derivations somewhere (no idea where) that aren't keeping their override. Probably using overrideAttrs or something? Then some other Haskell derivation depends on one without an override. Its env therefore tries to use such a derivation as a Haskell build input, but it has no override attribute for nullSrc.

The trouble is tracking down which derivations are responsible, because it's not showing up in the stack trace :/

[vcunat]

For testing you can always run nix build -f pkgs/top-level/release.nix tarball. Beware that some phases eat something like 12 GB RAM.