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From: "jason at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/53220] [4.7/4.8 Regression] g++ mis-compiles compound literals
Date: Mon, 07 May 2012 17:55:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53220

--- Comment #8 from Jason Merrill <jason at gcc dot gnu.org> 2012-05-07 17:44:52 UTC ---
The thing is, C++11 introduces list-initialized temporaries; I could rewrite
the testcase in C++11 as

extern "C" int printf (const char *, ...);

int main()
{
  typedef int AR[4];
  for (int *p = AR{1,2,3,0}; *p; ++p)
    {
      printf ("%d\n", *p);
    }
  return 0;
}

so it made sense to me for compound literals to have the same semantics;
otherwise you have a difference in lifetime based on whether or not the type is
wrapped in parentheses.

I definitely agree that we need to give a diagnostic about taking the address
of a temporary here.