Re: [gentoo-alt] clang on Mac OS X (Was: Question before setting up sage-on-gentoo)

[Michael Weiser]

Hi Fabian,

On Sat, Jan 31, 2015 at 07:54:50PM +0100, Fabian Groffen wrote:

> > > > There is a patch in a bug that lifts that limitation:
> > > > https://bugs.gentoo.org/show_bug.cgi?id=537826. With that in place in
> > > > the gcc ebuild and recompiled gcc you can override
> > > I'll apply this and lift the awkward limitation.
> >
> > This might need to be done in quite some steps: Can you have a
> I disagree.  A crude hack was put in place to make 10.10 support sort of
> going.  We can make all necessary changes to get it bootstrapping,
> although they may feel (and will be) disruptive.

Agreed. That makes it whole lot easier.

> > A proper Gentoo-compatible GCCInstallationDetector for Darwin would be
> > nice though, wouldn't it?
> Yes :)

It wasn't all that hard. Mostly reverse-engineering of perverse C++
criss-cross-method-calling and class-incest. Otherwise mostly
copy'n'paste from the Linux driver. Patches are ready for a test-drive
here: https://bugs.gentoo.org/show_bug.cgi?id=537342.

> > There might be a compromise but that would mean replacing all the xc-run
> > calls in the Makefiles so that the SDKs can stay enabled and remain in
> > use but with our freshly built compiler. I think that would make for
> > quite a large patch.
> Yes, but IMO we can delay that.

It kinda suddenly splurted out of diff and was finished. For now it's
only deactivation of the Xcode tools. I've left the SDKS enabled to see
if they're used at all if the Xcode tools are disabled. I would like to
have the MacOSX SDK disabled but the iOS SDK enabled to get the best of
all worlds. And on my 10.10 that seems to be exactly what happens
although I'm not quite sure why.

BTW: It seems that clang doesn't do and doesn't even support a gcc-style
multi-stage bootstrap recompiling itself with itself. So I've just left
it at compiling all of it using the installed prefix clang instead of
Xcode's.
-- 
bye,
Michael