Re: Two linkers - EFI one (mingw64) and normal GNU one [Fedora]

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Mon, Feb 15, 2016 at 02:32:45AM -0700, Jan Beulich wrote:
> >>> On 12.02.16 at 18:19, <konrad.wilk@oracle.com> wrote:
> > Fedora for the longest time seems to have two linkers - one normal for GNU
> > applications and then another - mingw64 - for building EFI applications.
> > 
> > Which means that to compile ELF binaries on Fedora requires this patch
> > (taken from Fedora build):
> 
> This seems completely backwards: Just like we (SUSE) did, they
> should really configure their binutils package with
> --enable-targets=<arch>-pep. I absolutely cannot see why a
> MingW64 linker should be used to generate EFI binaries. Yes,
> both use the same binary container format, but beyond that
> there's nothing common here: EFI binaries are of no use in a
> MingW64 environment (afaict at least), but are nowadays an
> integral part of an OS installation (i.e. a Linux distro in this case).

It has been like this for the last couple of releases. MA Young
has been CC-ed on this thread so hopefully he has some idea of why it
was choosen this way.
> 
> If it can be proven that Fedora folks are absolutely unwilling to
> do so, I could see something like what you propose as a
> workaround (albeit it's more like a hack), so a few comments on
> the patch itself:
> 
> > --- a/xen/Makefile
> > +++ b/xen/Makefile
> > @@ -20,6 +20,8 @@ export XEN_ROOT := $(BASEDIR)/..
> >  MAKEFLAGS += -rR
> >  
> >  EFI_MOUNTPOINT ?= $(BOOT_DIR)/efi
> > +EFI_VENDOR=fedora
> 
> This is a no-go. The variable specifically should only be set from
> outside our build environment.

Right.
> 
> > +LD_EFI ?= $(LD)
> 
> Why couldn't you just probe the binary location(s) you know about
> here? But in any case this would perhaps need better integration
> with the checking done in xen/arch/x86/efi/Makefile.

<nods>
I can certainly do that.

Doug, does Gentoo have it in some other locations?
> 
> Jan
>