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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/86385] calling wrong constructors?
Date: Thu, 13 May 2021 13:03:04 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D86385

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2018-07-03 00:00:00         |2021-5-13

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
It's not calling the wrong constructor, GCC is just making a trivial copy of
the object (without using any constructor) for the second operand of the ?:
expression. That is never constructed using a constructor, but it is destro=
yed,
which causes the double free.

;; Function main (main, funcdef_no=3D14, decl_uid=3D2419, cgraph_uid=3D15,
symbol_order=3D14) (executed once)

int main ()
{
  struct A D.2421;
  struct A D.2423;
  void * _8;

  <bb 2> [local count: 1073741824]:
  D.2421 =3D{v} {CLOBBER};
  _8 =3D operator new (4);
  MEM[(int *)_8] =3D 42;
  D.2421.a =3D _8;
  __builtin_printf ("C %p\n", &D.2421);
  D.2423 =3D D.2421;
  A::~A (&D.2423);
  D.2423 =3D{v} {CLOBBER};
  A::~A (&D.2421);
  D.2421 =3D{v} {CLOBBER};
  return 0;

}=