[Bug debug/83758] ICE building gccgo on powerpc64le --with-cpu=power8

["acsawdey at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83758

--- Comment #22 from acsawdey at gcc dot gnu.org ---
On genoa (power8, glibc 2.22 or 2.23) this compile always ICEs regardless of
how gcc was built:

/home/sawdey/src/gcc/trunk/build/./gcc/gccgo
-B/home/sawdey/src/gcc/trunk/build/./gcc/
-B/home/sawdey/install/gcc/trunk/powerpc64le-unknown-linux-gnu/bin/
-B/home/sawdey/install/gcc/trunk/powerpc64le-unknown-linux-gnu/lib/ -isystem
/home/sawdey/install/gcc/trunk/powerpc64le-unknown-linux-gnu/include -isystem
/home/sawdey/install/gcc/trunk/powerpc64le-unknown-linux-gnu/sys-include -O2
-mcpu=power8 -g -I . -c -fgo-pkgpath=cmd/go/internal/work
../../../trunk/libgo/go/cmd/go/internal/work/action.go
../../../trunk/libgo/go/cmd/go/internal/work/build.go
../../../trunk/libgo/go/cmd/go/internal/work/buildid.go
../../../trunk/libgo/go/cmd/go/internal/work/exec.go
../../../trunk/libgo/go/cmd/go/internal/work/gc.go
../../../trunk/libgo/go/cmd/go/internal/work/gccgo.go
../../../trunk/libgo/go/cmd/go/internal/work/init.go -o cmd/go/internal/work.o

I've tried:

configure --enable-languages=c,c++,go --enable-bootstrap --with-cpu=power6

configure --enable-languages=c,c++,go --disable-bootstrap --with-cpu=power4

and various combinations of the system gcc (5.4.0) and AT10 (6.4.1) without
success.

Bootstrap will succeed if you use --with-cpu=powerN where N<8 but that is just
because the above compile succeeds for that case. If you use the compiler built
that way and try the compilation above which includes -mcpu=power8, it fails.

So unless somebody does have a way to reproduce the command above succeeding
(with split-stack enabled) I feel like we can rule out the allegation that this
bug is dependent on how the compiler itself is built.