[Bug rtl-optimization/78812] [5/6/7 Regression] Wrong code generation due to hoisting memory load across function call

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78812

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2016-12-15
   Target Milestone|---                         |5.5
            Summary|Wrong code generation due   |[5/6/7 Regression] Wrong
                   |to hoisting memory load     |code generation due to
                   |across function call        |hoisting memory load across
                   |                            |function call
     Ever confirmed|0                           |1

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
But in the end it actually is a regression that started r166555 (previously it
has been latent).

Slightly adjusted testcase:
struct T
{
  bool a;
  T () : a (false) {}
  ~T () { if (!a) __builtin_abort (); }
};

__attribute__((noinline))
void
test (T &x)
{
  x.a = true;
}

int
main ()
{
  T T;
  test (T);
}