powerpc64 graphics/mesa-dri build failure in poudriere, system clang's /usr/bin/cc got assert failure: "Target supports vector op, but scalar requires expansion?"

[Ralf Wenk]

On 2019-05-23, at 12:31 -0700, Mark Millard wrote:
> On 2019-May-23, at 11:47, Jan Beich <jbeich at FreeBSD.org> wrote:
> 
> > Mark Millard <marklmi at yahoo.com> writes:
> > 
> >> Unfortunately poudiere bulk tar archives of failures do not
> >> catch the /tmp/* material from:
> >> 
> >> cc: error: unable to execute command: Abort trap (core dumped)
> >> cc: error: clang frontend command failed due to signal (use -v to see invocation)
> >> FreeBSD clang version 8.0.0 (tags/RELEASE_800/final 356365) (based on LLVM 8.0.0)
> >> Target: powerpc64-unknown-freebsd13.0
> >> Thread model: posix
> >> InstalledDir: /usr/bin
> > 
> > Do you have the build log? Maybe it's possible to reproduce simply by adding
> > -target powerpc64-unknown-freebsd13.0 while cross-building that particular file
> > using otherwise the same command line options as native build.
> 
> I have expanded the poudriere bulk's tar of the failure and rerun the
> command from there. The problem reproduced:
> 
> # ls -lTdt /tmp/nir_constant_expressions-9b094e.*
> -rw-r--r--  1 root  wheel    11069 May 23 12:08:35 2019 /tmp/nir_constant_expressions-9b094e.sh
> -rw-r--r--  1 root  wheel  1951892 May 23 12:08:35 2019 /tmp/nir_constant_expressions-9b094e.c
> 
> 
> So I gzip'd the .c and created:
> 
> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=238082
> 
> with the two files as 2 attachments.

This looks familiar to me. Is the kernel you are using at r348115 or newer?

r348115 triggers such kind of "unable to execute" compiler errors on my
system. See https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=238084

Ralf