FYI: I have a patch for the aarch64 regression here: https://gcc.gnu.org/bugzilla/attachment.cgi?id=39600
It passes bootstrap and reg-testing on x86_64-linux-gnu. Also the mentioned aarch64 and powerpc test cases pass manually in a cross-compiler, but I cannot do the boot-strap on powerpc or aarch64 by myself. So It would be nice if one of you would take the time and try that patch. Thanks Bernd.