[Bug bootstrap/88133] New: [9 Regression] Build fails with host GCC < 4.3

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88133

            Bug ID: 88133
           Summary: [9 Regression] Build fails with host GCC < 4.3
           Product: gcc
           Version: 9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
          Assignee: unassigned at gcc dot gnu.org
          Reporter: rguenth at gcc dot gnu.org
  Target Milestone: ---

Those do not grok

bitmap.o-warn = -Wno-error=array-bounds # PR 87926

in reload1.c we seem to use #pragma GCC diagnostic so maybe we can
just guard appropriate pieces of bitmap.c?  Not sure if the
diagnostic support works for warnings emitted by optimization passes.

Note that GCC 4.2 and earlier do not know -Warray-bounds and error
for unknown warning options.

Not sure what other host comilers do, at least I didn't see any
report yet for the other -Wno- pieces we use.