[Bug debug/71667] New: [7 Regression] ICE in as_a, at is-a.h:192 w/ -g -O2 -ftree-vectorize

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71667

            Bug ID: 71667
           Summary: [7 Regression] ICE in as_a, at is-a.h:192 w/ -g -O2
                    -ftree-vectorize
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: debug
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---

gcc-7.0.0-alpha20160619 ICEs on the following reduced testcase w/ -O2 (-O3,
-Ofast) -g -ftree-vectorize:

unsigned int mu;
int pt;

void
qf (void)
{
  int gy;
  long int vz;

  for (;;)
    {
      for (gy = 0; gy < 80; ++gy)
      {
        vz = mu;
        ++mu;
        pt = (vz != 0) && (pt != 0);
      }
      while (gy < 81)
        while (gy < 83)
          {
            vz = (vz != 0) ? 0 : mu;
            ++gy;
          }
      pt = vz;
      ++mu;
    }
}

% gcc-7.0.0-alpha20160619 -c -O2 -g -ftree-vectorize jjgn2cjj.c      
jjgn2cjj.c: In function 'qf':
jjgn2cjj.c:5:1: internal compiler error: in as_a, at is-a.h:192
 qf (void)
 ^~