[Bug tree-optimization/105990] New: Dead code elimination failed at -O3

[crazylht at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105990

            Bug ID: 105990
           Summary: Dead code elimination failed at -O3
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: crazylht at gmail dot com
  Target Milestone: ---

static struct { int a; } b, c;
static int d = -1;
void foo();
int main() {
    if (b.a)
        d = 2 | (b.a <= 0);
    for (; b.a; b.a++)
        c = b;
    if (!d)
        foo();
}


foo() can be eliminated since d would never be zero.