bug#45934: native-comp - Dylib ID of ELN files not optimal

[Alan Third]

On Thu, Aug 05, 2021 at 12:54:09PM +0200, Lars Ingebrigtsen wrote:
> Alan Third <alan@idiocy.org> writes:
> 
> > I'm not sure about with MacPorts, but with Homebrew it should just be
> > a case of installing libgccjit and configuring as normal.
> 
> With Macports, Configuring as normal just gets me clang (masquerading as
> /usr/bin/cc), but I can say "CC=/that/macports/gcc ./configure", but it
> doesn't find the libgccjit stuff.

You don't need to build with gcc to use libgccjit, and in fact you
can't build the GUI with gcc at all.

I finally found the code that works it out for Homebrew. I've never
used MacPorts but I think all you need to do is something similar to
(from configure.ac:3820):

    CFLAGS="$CFLAGS -I${BREW_LIBGCCJIT_PREFIX}/include"
    LDFLAGS="$LDFLAGS -L${brew_libdir} -I${BREW_LIBGCCJIT_PREFIX}/include"

Where "${BREW_LIBGCCJIT_PREFIX}/include" is where the include files
are and ${brew_libdir} is where the .so files are.

This is relatively easy to automate with Homebrew because we can just
ask it where libgccjit is installed and then work out the paths, but
I don't know about Macports.

> > If it's an Arm mac then I think it requires gcc 11.
> >
> > I don't know why the Mac community tends towards maintaining huge
> > scripts and/or lists of configure flags for building Emacs, because in
> > my experience they're not required, but it does seem to be the norm.
> 
> Yeah, building on Macos is almost as trivial as on Debian (at least with
> clang), but there's all these really convoluted scripts out there...
> 
> My hope was that it was as simple to build with the Macports gcc, too,
> but...  apparently not?  (I'd rather not install Homebrew, too, on this
> laptop -- that just sounds too confusing.)

I'm sure it must be easy enough. Homebrew is a bit of a pain in the
backside because it intentionally leaves many installed packages
unavailable so as not to interfere with the normal macOS install. I
was under the impression that Macports was a simpler set-up.
-- 
Alan Third