[Bug target/77676] powerpc64 and powerpc64le stage2 bootstrap fail

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77676

--- Comment #9 from Martin Sebor <msebor at gcc dot gnu.org> ---
I found the problem responsible for the incorrect code generation but I have
disabled the optimization until I have a robust solution.  The ILP32 warning in
comment #6 is a separate issue.  I'm looking into it.

The warning in comment #4 looks legitimate and should be fixable by enlarging
the destination buffer to 15 bytes as suggested in the note.