Re: [PATCH v2] Introduce multiarch DISTRO_FEATURE

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Wed, 2011-11-23 at 16:39 +0000, Julian Pidancet wrote:
> On Wed, Nov 16, 2011 at 1:01 AM, Julian Pidancet
> <julian.pidancet@gmail.com> wrote:
> > This patch introduces a distro feature which enables gcc to produce
> > both 32bit and 64bit code, and enables binutils to operate on both
> > 32bit and 64bit binaries. It differs from multilib toolchains in
> > that it does not require to compile a version of the libc for each
> > architecture variant. However, the code produced for the secondary
> > architecture will not be linkable against the libc.
> >
> > v2: - Renamed the feature name from "biarch" to "multiarch". The GCC
> > installation manual claims that the mips-linux can be made a tri-arch
> > compiler (http://gcc.gnu.org/install/configure.html)
> >    - For x86_64, the compiler is made bi-arch by default, so nothing
> > has to be done in particular.
> >    - I analyzed the gcc/config.gcc from GCC sources and added in this
> > patch all the architectures that could be made biarch with the version
> > of gcc currently used in OE, which are powerpc, and sparc, in addition
> > to x86. mips and s390 will probably be supported in future versions of
> > gcc. For x86 and sparc, only the --enable-targets=all option is valid
> > to make this work (this option doesn't have any other side effects than
> > making the compiler bi-arch). For powerpc, I used the
> > --enable-targets=powerpc64 option (although 'all' also works).
> >
> > Note: - Untested on powerpc and sparc. But I believe it works the same
> > as with x86.
> >      - gcc in meta-toolchain is also made multiarch.
> >
> 
> Anybody got the time to review this ?

Funnily enough I was just talking with Saul about this. We're going to
try and expose this to some extended testing (which we try and do for
all compiler changes).

Cheers,

Richard