namespace A { int x = 1; }
namespace B { int x = 2; }
int main (void)
{
  using namespace A;
  using namespace B;
  return 0;
}
------------------------------------------------------------------------------
If I would use `return x;' the compiler would complain:
1.C:7: error: reference to ‘x’ is ambiguous
1.C:2: error: candidates are: int B::x
1.C:1: error:                 int A::x
------------------------------------------------------------------------------
But in GDB I get:
7	  return 0;
(gdb) p x
$1 = 1
and after I switch
  using namespace B;
  using namespace A;
I get:
(gdb) p x
$1 = 2
------------------------------------------------------------------------------
GDB thus does not have the behavior of compiler.  Expecting something like:
(gdb) p x
Reference to ‘x’ is ambiguous, candidates are `int B::x', `int A::x'.