Workaround for ghcjs hardcoding to linux #511
Conversation
| else nixpkgs.haskell.lib.overrideCabal package (drv: { | ||
| postPatch = (drv.postPatch or "") + nixpkgs.lib.optionalString (system == "x86_64-darwin") '' | ||
| substituteInPlace ${cabalFile}.cabal --replace 'if os(linux)' 'if os(linux) && !impl(ghcjs)' | ||
| substituteInPlace ${cabalFile}.cabal --replace 'if os(osx)' 'if os(linux) && impl(ghcjs)' |
There was a problem hiding this comment.
Is this right? if os(osx) gets translated to if os(linux) ...?
There was a problem hiding this comment.
If it is right...an explanation is worthy.
There was a problem hiding this comment.
Talked to @alexfmpe. So basically this is just a very confusing way of writing it. Because of the hardcoding in GHCJS, os(linux) == true and true && x == x so why are we confounding this substitution?
There was a problem hiding this comment.
We don't want the os(linux) patches to get applied, so we change the os(linux) conditional to only apply when GHCJS isn't being used. Since GHCJS always thinks it's running on Linux, we change the os(osx) patches to os(linux) patches.
There was a problem hiding this comment.
There was a problem hiding this comment.
because we don't want to apply the actual os(linux) patches (since we're really on macOS)
There was a problem hiding this comment.
GHCJS thinks we're on Linux, but that doesn't mean we should apply the Linux patches, instead we need to trick GHCJS into applying the macOS patches
There was a problem hiding this comment.
so we say "these linux patches are not for you, silly GHCJS, but these other (actually macOS) linux patches are!"
There was a problem hiding this comment.
Note the replacement only happens if system == "x86_64-darwin"
|
As @3noch said, this needs a more informative comment/explanation. Rather than substitute-in-place, please create a patch file and apply it. Please also document where the upstream PR we're waiting on can be found. |
|
ghcjs/ghcjs#702 mentions the issues. |
Due to ghcjs/ghcjs#674
Upstreaming @vaibhavsagar's fix since we both ran into this on different projects.
Test case: obsidiansystems/obelisk@develop...alexfmpe:ae-error-foundation