Cannot build with the JS backend on darwin

[Swordlash]

Repro: install javascript-unknown-ghcjs-ghc-9.12.1 from ghcup, clone master and

mateusz@Mateuszs-MacBook-Pro clock % cabal build --with-compiler=javascript-unknown-ghcjs-ghc-9.12.1 --with-hc-pkg=javascript-unknown-ghcjs-ghc-pkg-9.12.1
Configuration is affected by the following files:
- cabal.project
Resolving dependencies...
Build profile: -w ghc-9.12.1 -O1
In order, the following will be built (use -v for more details):
 - clock-0.8.4 (lib) (first run)
Configuring library for clock-0.8.4...
Preprocessing library for clock-0.8.4...
emcc: error: unsupported target: arm64-apple-darwin (emcc only supports wasm64-unknown-emscripten and wasm32-unknown-emscripten)
compilation failed
Error: [Cabal-7125]
Failed to build clock-0.8.4.