[Bug c++/70272] New: [5/6 Regression] -flifetime-dse miscompilation starting with r217967

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70272

            Bug ID: 70272
           Summary: [5/6 Regression] -flifetime-dse miscompilation
                    starting with r217967
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jakub at gcc dot gnu.org
  Target Milestone: ---

struct Empty { };
struct A { A() : a(true) { } bool a; ~A() { if (!a) __builtin_abort(); } };
struct B : Empty { B() : Empty() { } ~B() { } };
struct C : A, B { C() : A(), B() { } ~C() { } };
int main() {
  C c;
}

is miscompiled at -O2 starting with r217967.
This is the dtor counterpart of PR70259.