gcc/testsuite/g++.dg/cpp1z/init-statement3.C

// { dg-do run { target c++17 } }
// Test C++17 selection statements with initializer, side-effects.

int
main ()
{
  int g = 0;

  if (g++; g > 1)
    __builtin_abort ();
  if (++g; g > 2)
    __builtin_abort ();
  if (g != 2)
    __builtin_abort ();
}