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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/106502] Three calls to __attribute__((const)) function
Date: Tue, 02 Aug 2022 06:41:49 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D106502

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
It doesn't happen unless the name() function is virtual. Reduced:


extern "C" int puts(const char*);

struct Cat
{
  virtual const char* name();
};

__attribute__((const)) Cat& cat();

int main()
{
  puts(cat().name());
}


Produces this gimple:

int main ()
{
  int D.2388;

  _1 =3D cat ();
  _2 =3D cat ();
  _3 =3D _2->_vptr.Cat;
  _4 =3D *_3;
  _5 =3D cat ();
  _6 =3D OBJ_TYPE_REF(_4;(struct Cat)_1->0B) (_5);
  puts (_6);
  D.2388 =3D 0;
  return D.2388;
}=