GHC HEAD is a pre basically pre GHC 9.8 (or rather 9.7 something).
Let's name the configuration like the upcoming release, so we can use it
immediately when the new release comes out. Instead of keeping the HEAD
configuration like we used to, we'd create a new (empty) one.
Stage1 and Stage2 will unconditionally build xhtml with hadrian:
496607fdb7/hadrian/src/Settings/Default.hs (L140)
terminfo is still conditional on non-cross (and not windows host which
doesn't matter that much, as we don't have native windows support atm).
GHC's cross build flavours disable the terminfo package, so it will
never be included if we are cross-compiling – setting it to null thus
breaks all builds depending on the package.
To fix this problem, we use the versioned attribute generated by
hackage2nix, just like we do for xhtml.
Closes#182785.
The xhtml library is only built as part of the GHC build process if GHC
is disabled. This means that no GHC cross compiler has xhtml bundled,
since haddock can't be built if GHC is a cross compiler (see relevant
notes in the GHC nix expressions). This means that all packages
depending on xhtml would currently fail to build when cross-compiled, as
haskellPackages would assume it'd be provided by GHC. This is fixed by
this commit.
pkgsStatic hits this case, so we test compilation of xhtml for these
package sets which will remind us to update the attribute name whenever
its version changes.
This means we only have to update the llvmPackages attribute in one
place now and should prevent situations like with 8.6.5 where different
versions would be used in the package set compared to the compiler
build.
Drop comments in the configuration-ghc-X.Y.x.nix files as well, since
LLVM version isn't tied to the compiler minor version at
all (e. g. 8.10.2 and 8.10.7 have different support ranges).
They are not an exposed part of haskellPackages per se, so we shouldn't
list them in nix-env. Additionally this should prevent the failed lldb
build from cluttering our jobset output.
- The haskell lib is very close to not relying on Nixpkgs. I think
this is good---simpler to think about and matches Nixpkgs's lib.
- The haskell lib is only imported once
- stdenv is exposed more shallowly so it can be overriden more easily.
I'll eventually use this on Darwin to avoid the Sierra shared
library problems (unless changes are to be made system-wide).
Closes https://github.com/NixOS/nixpkgs/pull/27840.