[Bug libgcc/77571] New: __clear_cache is broken on platforms that report different cache line sizes across CPUs

[beurba at microsoft dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77571

            Bug ID: 77571
           Summary: __clear_cache is broken on platforms that report
                    different cache line sizes across CPUs
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libgcc
          Assignee: unassigned at gcc dot gnu.org
          Reporter: beurba at microsoft dot com
  Target Milestone: ---

This patch introduces a problem:
https://gcc.gnu.org/ml/gcc-patches/2012-09/msg00076.html and should be at least
reverted.

See https://github.com/mono/mono/pull/3549 and
http://www.mono-project.com/news/2016/09/12/arm64-icache/

There is also some work going on to fix this on kernel level:
https://gcc.gnu.org/ml/gcc-patches/2012-09/msg00076.html