[Bug middle-end/62103] Incorrect folding of bitfield in a union on big endian targets

[thopre01 at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62103

--- Comment #2 from thopre01 at gcc dot gnu.org ---
I forgot to mention the flag to use: -O1 and whatever flag is necessary to
select a big endian target (for instance -mbig-endian if the target is arm
little endian by default).