[Bug bootstrap/80455] New: -Werror=coverage-mismatch in profiledboostrap despite --disable-werror

["msebor at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80455

            Bug ID: 80455
           Summary: -Werror=coverage-mismatch in profiledboostrap despite
                    --disable-werror
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
          Assignee: unassigned at gcc dot gnu.org
          Reporter: msebor at gcc dot gnu.org
  Target Milestone: ---

Current top of trunk (GCC 7) configured with
--enable-languages=ada,all,c,c++,fortran,go,lto,objc,obj-c++
-with-build-config=bootstrap-lto --disable-werror fails in stagefeedback with
the following errors

get_d.c:412:1: error: the control flow of function ‘__gmpn_get_d’ does not
match its profile data (counter ‘arcs’) [-Werror=coverage-mismatch]
get_d.c:412:1: error: the control flow of function ‘__gmpn_get_d’ does not
match its profile data (counter ‘time_profiler’) [-Werror=coverage-mismatch]

A search through the build log for get_d.c and -Werror turns up nothing:

$ grep get_d\.c /build/gcc-trunk-profiledbootstrap/profiledbootstrap.log | grep
Werror
get_d.c:412:1: error: the control flow of function ‘__gmpn_get_d’ does not
match its profile data (counter ‘arcs’) [-Werror=coverage-mismatch]
get_d.c:412:1: error: the control flow of function ‘__gmpn_get_d’ does not
match its profile data (counter ‘time_profiler’) [-Werror=coverage-mismatch]

However, as pointed out in bug 32193, libgomp is still built with -Werror, so I
suspect the error is the result of that.