[006/nnn] poly_int: tree constants

[Pedro Alves]

On 10/26/2017 07:54 PM, Martin Sebor wrote:

> (...) in the general case, it is preferable to
> declare each variable at the point where its initial value is known
> (or can be computed) and initialize it on its declaration.

With that I fully agree, except it's not always possible or
natural.  The issue at hand usually turns up with
conditional initialization, like:

void foo ()
{
  int t;
  if (something)
    t = 1;
  else if (something_else)
    t = 2;
  if (t == 1)
    bar (); 
}

That's a simple example of course, but more complicated
conditionals aren't so easy to grok and spot the bug.

In the case above, I'd much prefer if the compiler tells me
I missed initializing 't' than initializing it to 0 "just
in case".

Thanks,
Pedro Alves