[Bug tree-optimization/56756] New: ICE: verify_ssa failed (definition in block n follows the use !)

[antoine.balestrat at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56756

             Bug #: 56756
           Summary: ICE: verify_ssa failed (definition in block n follows
                    the use !)
    Classification: Unclassified
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: antoine.balest...@gmail.com


Using GCC 4.9.0 as of 20130327 :

$ cat ssa.c
int a, *b;

void f(void)
{
    if(a)
    {
        int k;

        for(a = 0; a < 1; a++)
        {
            int **q;
            f();

            for(; **q; ++**q)
lbl:
                if(a)
                {
                    a = 0;
                    goto lbl;
                }

            b = &k;
        }
    }
    goto lbl;
}

$ xgcc -O1 -w ssa.c
ssa.c: In function ‘f’:
ssa.c:3:6: error: definition in block 12 follows the use
 void f(void)
      ^
for SSA_NAME: _17 in statement:
# VUSE <.MEM_21>
D__lsm.5_2 = *_17;
ssa.c:3:6: internal compiler error: verify_ssa failed
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.