PATCH to use -Wno-format during stage1

[Jakub Jelinek]

On Mon, Nov 04, 2013 at 10:34:55AM -0500, Jason Merrill wrote:
> On 11/04/2013 07:41 AM, Richard Biener wrote:
> >Please make sure the warning is preserved when not bootstrapping,
> >it's useful to have them in your dev-tree and not notice errors only
> >during -Werror bootstrap ...
> 
> I found it to be useless noise when not bootstrapping, since my
> system compiler isn't likely to recognize recently added % codes any
> time soon.

That's true, but it is easy to ignore those, while without -Wformat
you won't notice until you bootstrap that you actually passed incorrect
parameters to some *printf etc. family function.  Generally, in
non-bootstrap compilers I tend to ignore warnings except for the
file(s) I've been hacking on.

	Jakub