emscriptenStdenv: create writable cache directory

[willcohen]

Description of changes

In the configurePhase of emscriptenStdenv, create a subdirectory that can be used for the internal emscripten cache. Fixes #139943 and #170621.

Issue broke zlib with the update to 3.0 in #149083.

Additionally this modified the derivation for zlib to just use the emscriptenStdenv configure phase, and then adds the same changes to the other derivations that make larger modifications.

@arximboldi @busti
@qknight @matthewbauer

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandbox = true set in nix.conf? (See Nix manual)
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 22.05 Release Notes (or backporting 21.11 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
  • (Release notes changes) Ran nixos/doc/manual/md-to-db.sh to update generated release notes
• Fits CONTRIBUTING.md.

[willcohen]

Additionally, referencing ZHF: #172160

[willcohen]

nixpkgs-review is failing to build anything new but using nix-build $NIXPKGS emscriptenPackages.zlib, .libxml2, .json_c shows successful builds for me. .xmlmirror has more failures but that appears to involve the derivation being a little more brittle, which will require some more tweaks.

[arximboldi]

This is great, thank you so much @willcohen !!

[willcohen]

@NixOS/release-engineers
I know that this doesn't technically reduce the red number on hydra since emscripten packages don't seem to build there automatically , but it does still seem in the spirit of ZHF to fix the build of at least 3 of the 4 emscriptenPackages, since they've all been broken since the upgrade to emscripten 3.

[willcohen]

Thank you!

[pca006132]

Hi, I wonder if it is possible to document this in doc/languages-frameworks/emscripten.section.md, so we will know what to do when we override the configure phase, e.g. for building cmake based projects.

[willcohen]

See #181363!

[nixos-discourse]

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/improving-an-emscripten-yarn-dev-shell-flake/33045/1