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 tangotests.templ1;

import Util = tango.text.Util;

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

void main()
{
    foreach (line; Util.lines("a\nb\nc"))
    {
        printf("%.*s\n", line.length, line.ptr);
    }
}