[Bug c++/66487] [6 Regression] Firefox segfault with LTO enabled

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66487

--- Comment #10 from Martin Liška <marxin at gcc dot gnu.org> ---
_ZL33nsSafeFileOutputStreamConstructorP11nsISupportsRK4nsIDPPv.part.50 (const
struct nsIID & aIID, void * * aResult)
{
  nsresult rv;
  struct nsSafeFileOutputStream * inst;
  void * D.4108055;
  struct nsISupports * aOuter;

  <bb 5>:

  <bb 2>:
  _1 = moz_xmalloc (96);
  MEM[(struct nsSafeFileOutputStream *)_1] = {};
  _2 = &MEM[(struct nsFileOutputStream *)_1].D.310165;
  __base_ctor  (_2);
  MEM[(struct nsCOMPtr_base *)_1 + 72B].mRawPtr = 0B;
  MEM[(struct nsCOMPtr_base *)_1 + 80B].mRawPtr = 0B;
  MEM[(struct nsAtomicFileOutputStream *)_1].mTargetFileExists = 1;
  MEM[(struct nsAtomicFileOutputStream *)_1].mWriteResult = 0;
  MEM[(struct nsSafeFileOutputStream
*)_1].D.311327.D.310176.D.310165.D.310152.D.135481._vptr.nsISupports =
&MEM[(void *)&_ZTV22nsSafeFileOutputStream + 16B];
  MEM[(struct nsSafeFileOutputStream
*)_1].D.311327.D.310176.D.310165.D.310151.D.309908._vptr.nsISupports =
&MEM[(void *)&_ZTV22nsSafeFileOutputStream + 184B];
  MEM[(struct nsSafeFileOutputStream
*)_1].D.311327.D.310176.D.310164.D.121781.D.40458._vptr.nsISupports =
&MEM[(void *)&_ZTV22nsSafeFileOutputStream + 240B];
  MEM[(struct nsSafeFileOutputStream
*)_1].D.311327.D.310175.D.121735._vptr.nsISupports = &MEM[(void
*)&_ZTV22nsSafeFileOutputStream + 336B];
  if (_1 == 0B)
    goto <bb 4>;
  else
    goto <bb 3>;

  <bb 3>:
  _3 = &MEM[(struct nsSafeFileOutputStream *)_1].D.311327;
  _4 = MEM[(int (*__vtbl_ptr_type) () *)&_ZTV22nsSafeFileOutputStream + 24B];
  OBJ_TYPE_REF(_4;(struct nsAtomicFileOutputStream)_3->1) (_3);
  _5 = MEM[(struct nsSafeFileOutputStream
*)_1].D.311327.D.310176.D.310165.D.310152.D.135481._vptr.nsISupports;
  _6 = *_5;
  rv_9 = OBJ_TYPE_REF(_6;(struct nsAtomicFileOutputStream)_3->0) (_3,
aIID_7(D), aResult_8(D));
  _10 = MEM[(struct nsSafeFileOutputStream
*)_1].D.311327.D.310176.D.310165.D.310152.D.135481._vptr.nsISupports;
  _11 = MEM[(int (*__vtbl_ptr_type) () *)_10 + 16B];
  OBJ_TYPE_REF(_11;(struct nsAtomicFileOutputStream)_3->2) (_3);

  <bb 4>:
  # _12 = PHI <2147942414(2), rv_9(3)>
  return _12;

}