Teach stack promotion to walk the CFG when a potential reuse of an allocation is found to see if it can actually happen instead of just assuming it will. This allows it to catch cases like {{{ int i; Foo f; while (cond(i)) f = new Foo(i++); return f.value; }}} where it previously wouldn't because a phi using the allocation would appear in the condition block to propagate it to the use after the loop.

module constructors;

import tango.io.Console;

class C
{
    this()
    {
        Cout("C()").newline;
    }
    this(char[] str)
    {
        Cout("C(")(str)(")").newline;
    }
}

class D : C
{
    this()
    {
        super("D");
        Cout("D()").newline;
    }
}

void main()
{
    auto c1 = new C();
    auto c2 = new C("C");
    auto d = new D();
}