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From: "hubicka at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/112653] PTA should handle correctly escape
 information of values returned by a function
Date: Thu, 23 Nov 2023 15:10:02 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D112653

--- Comment #7 from Jan Hubicka <hubicka at gcc dot gnu.org> ---
Thanks for explanation.  I think it is quite common pattern that new object=
 is
construted and worked on and later returned, so I think we ought to handle =
this
correctly.

Another example just came up in
https://gcc.gnu.org/pipermail/gcc-patches/2023-November/637878.html

We should gnerate same code for the following two functions:

#include <vector>

auto
f()
{
  std::vector<int> x;
  x.reserve(10);
  for (int i =3D 0; i < 10; ++i)
    x.push_back(0);
  return x;
}

auto
g()
{ return std::vector<int>(10, 0); }


but we don't since we lose track of values stored in x after every call to =
new.=