Summary: | dev-lang/ghc-7.8.3 should depend on sys-devel/llvm | ||
---|---|---|---|
Product: | Gentoo Linux | Reporter: | redneb <redneb> |
Component: | [OLD] Development | Assignee: | Gentoo's Haskell Language team <haskell> |
Status: | RESOLVED WONTFIX | ||
Severity: | normal | ||
Priority: | Normal | ||
Version: | unspecified | ||
Hardware: | All | ||
OS: | Linux | ||
Whiteboard: | |||
Package list: | Runtime testing required: | --- | |
Bug Depends on: | 424283 | ||
Bug Blocks: |
Description
redneb
2014-10-05 02:24:12 UTC
ghc-7.6 had a comile-time knob: GhcWithLlvmCodeGen = YES / NO which basically enabled -fllvm flag and included small amount of code into ghc. It was a serious overhead in rebuilding ghc just to enable/disable llvm functionality. ghc-7.8 dropped that conditional dependency and always builds llvm support in it (llvm does not need to be present at build time). Having runtime-only switch is even worse from rebuilding standpoint. Unconditionally depend on llvm is infeasible (and not desired) because: - ghc's llvm support is experimental: - some architectures generate broken code with -fllvm - even amd64 does not pass all tests on llvm - some arcitectures are not supported by llvm at all (ia64) - current llvm-3.5 does not work with ghc-7.8.3 - llvm is a big thing to compile for quite small benefit. it would be nice to have llvm precisely expressed as a depend but it needs a runtime-only USE-flag support from portage. Which is a bug #424283 |