[Bug middle-end/69217] New: ICE at var-tracking.c:5038 Segmentation fault

[ibuclaw at gdcproject dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69217

            Bug ID: 69217
           Summary: ICE at var-tracking.c:5038 Segmentation fault
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ibuclaw at gdcproject dot org
  Target Milestone: ---

Starting from this commit, I have been seeing segfaults in the D frontend.

https://gcc.gnu.org/viewcvs/gcc/trunk/gcc/var-tracking.c?r1=231897&r2=231896&pathrev=231897

The equivalent C++ code is:

---
struct S1 { };

void __dtor (S1& pthis)
{
  return;
}


S1& opAssign (S1& pthis, S1 p)
{
  S1 __tmp1 = pthis;
  pthis = p;
  __dtor (__tmp1);
  return pthis;
}
---

However g++ does something that I don't, remove empty aggregate assignments.

While I should get round to fixing the gimplify stage to conform, I think the
middle-end should do something other than SEGV when this happens.

e.g:

  if (TYPE_FIELDS (type) == NULL_TREE
      || DECL_CHAIN (TYPE_FIELDS (type)) == NULL_TREE)
    return false;