Re: [PATCH] build: fix build on FreeBSD with Meson 0.61.1

[Thomas Monjalon <thomas@monjalon.net>]

15/02/2022 16:31, Bruce Richardson:
> On Mon, Feb 14, 2022 at 12:43:13PM +0100, Karl Bonde Torp wrote:
> > When building with Meson 0.61.1 on FreeBSD some archives become
> > corrupted. This can be avoided by using 'llvm-ar' instead of 'ar'.
> > 
> > Signed-off-by: Karl Bonde Torp <k.torp@samsung.com>
> > ---
> >  buildtools/meson.build | 3 +++
> >  1 file changed, 3 insertions(+)
> > 
> > diff --git a/buildtools/meson.build b/buildtools/meson.build
> > index 400b88f251..e1c600e40f 100644
> > --- a/buildtools/meson.build
> > +++ b/buildtools/meson.build
> > @@ -31,6 +31,9 @@ if host_machine.system() == 'windows'
> >          pmdinfo += 'llvm-ar'
> >      endif
> >      pmdinfogen += 'coff'
> > +elif host_machine.system() == 'freebsd'
> > +    pmdinfo += 'llvm-ar'
> > +    pmdinfogen += 'elf'
> >  else
> >      pmdinfo += 'ar'
> >      pmdinfogen += 'elf'
> 
> Based off the instructions you posted later in the thread, I've reproduced
> the issue - and then done a little extra investigation. Here is my
> understanding:
> 
> * By default on FreeBSD the linking is being done by llvm-ar
> * The resulting libraries are being linked as thin archives and "ar" binary
>   does not seem to be able to process them.
> * When building with CC=gcc on FreeBSD, "ar" is used as a linker, and the
>   resulting archives are regular .a files.
> * On Linux, whether building with clang or gcc, "ar" seems to be used as
>   linker.
> 
> The ideal situation here would be if we could use meson to report itself
> what the static linker in use is, but unfortunately while we can query the
> dynamic linker using "meson.compiler().get_linker_id()", there doesn't seem
> to be an equivalent for the static linker. Therefore, the only option seems
> to be a fix as here. Only question remains as to whether we want to only
> use llvm-ar for clang builds on FreeBSD or use if for all builds on FreeBSD.
> I'm not sure it makes much difference either way, but I'd tend towards
> limiting the use of llvm-ar to only clang builds.
> 
> With or without this suggested change,
> 
> Acked-by: Bruce Richardson <bruce.richardson@intel.com>

Applied, thanks.