https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71695
--- Comment #4 from Jeffrey A. Law <law at redhat dot com> --- Martin, No idea what might be going on here. Could you compile yourr testcase with "-fdump-tree-all-blocks-details -dap" on whatever system exhibits this problem and attach the slew of debugging dumps to this BZ. A compressed tarball would be fine.
