[macports-ports] branch master updated: ghc and ghc-bootstrap: specify compiler to clang-4.0

[Ken Cunningham]

On 2017-09-27, at 6:20 AM, Ryan Schmidt wrote:
> 
> MacPorts automatically adds a build dependency on the compiler it uses, if that compiler comes from MacPorts and if that dependency has not already been added, so having already specified the compiler whitelist you don't then also need to add the build dependency. 

will fix, thanks

> 
> So, now ghc requires both llvm-3.5 and llvm-4.0? Seems excessive. Could it be fixed to need only a single version of llvm?
> 

ghc 7 is essentially hand-coded to generate llvm-3.5 IR code and at the moment will not work with any other llvm version as a backend. I'm not sure if there are plans to change this.

clang-3.5 is not available, but could possibly build ghc if it was. So on older systems and 10.11 (which has an incompatible {clang} for some reason) you have to install some other version of clang/llvm.

Most of these systems need the cxx11 1.1 PortGroup anyway, and clang-4.0 works nicely on all 64 bit systems to build it 10.6+, so that seemed like the best choice. I think we're stuck with two llvm versions and one clang on older systems and 10.11.

No doubt there will come a day when ghc will move up to another newer llvm version...

Ken