failure of GHC 7.0.4 on OS X

[Ian Lynagh]

On Tue, Oct 04, 2011 at 10:28:34AM +0100, Duncan Coutts wrote:
> On Mon, 2011-10-03 at 22:50 -0700, Mark Lentczner wrote:
> 
> > In the future, we should try get the GHC build to work as far back as
> > 10.5 for 32-bit builds.
> 
> Is there anything that the upstream ghc devs need to fix or be aware of?

I don't think we have the resources to support (in the "tier 1 platform"
sense) old versions of OS X, although we always happy to receive
patches, of course.

> > [1] The executables die with
> >     dyld: unknown required load command 0x80000022
> > A little bit of googling yields that this is indicative of being compiled
> > with in an environment where the default SDK and min version were 10.6. To
> > change requires linking with:
> >     -mmacosx-version-min=10.5
> > (and possibly compiling against the 10.5 SDK, though that shouldn't be
> > needed since the GHC build should use nothing from the 10.6 SDK that isn't
> > in the 10.5 SDK.)
> 
> So is this something the ghc devs need to fix in the osx build scripts?

We used to use

    -isysroot /Developer/SDKs/MacOSX10.5.sdk -mmacosx-version-min=10.5

but I had to remove it:

    commit 6c073daacc2c44e218411e874c2eec9d53851d72
    Author: Ian Lynagh <igloo at earth.li>
    Date:   Sun Mar 13 14:03:22 2011 +0000

        Stop explicitly asking for 10.5 support on OS X; fixes #5011
        XCode 4 doesn't include the 10.5 SDK, so if we explicitly ask for it
        then linking fails.

I don't know if just

    -mmacosx-version-min=10.5

would (a) produce a GHC that works on 10.5, and (b) work on recent Macs
too. Unfortunately, I can't test (a). Also, even if it does work now, I
wouldn't be surprised if it broke in the near future.


Thanks
Ian