[Bug c/97354] New: ice during GIMPLE pass: slp

[dcb314 at hotmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97354

            Bug ID: 97354
           Summary: ice during GIMPLE pass: slp
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dcb314 at hotmail dot com
  Target Milestone: ---

The following C code:

int a, c, d;
_Complex *b;
_Complex e;
void f(void) {
  _Complex g;
  for (; a;) {
    e = b[0];
    for (; d; d++)
      b[c] = e;
  }
  e = g * 0;
}


with compiler flag -O3, does this:

during GIMPLE pass: slp
bug650.c: In function ‘f’:
bug650.c:4:6: internal compiler error: in as_a, at is-a.h:197
    4 | void f(void) {
      |      ^
0xf7b1b4 gphi* as_a<gphi*, gimple>(gimple*)
        ../../trunk.git/gcc/is-a.h:197
0xf7b1b4 gphi_iterator::phi() const
        ../../trunk.git/gcc/gimple-iterator.h:43
0xf7b1b4 _bb_vec_info::~_bb_vec_info()
        ../../trunk.git/gcc/tree-vect-slp.c:2777
0xf7dcf0 vect_slp_region(vec<basic_block_def*, va_heap, vl_ptr>,
vec<data_reference*, va_heap, vl_ptr>, vec<int, va_heap, vl_ptr>*, unsigned
int)
        ../../trunk.git/gcc/tree-vect-slp.c:3741

The bug first seems to occur sometime between 20201008 and 20201009.