Re: m32c: pointer math vs sizetype again

[Ian Lance Taylor <iant at google dot com>]

DJ Delorie <dj@redhat.com> writes:

>> Does the following fix it?
>
> Nope, sorry.  I was looking at this code in c-common.c, where the expr
> is first created, but I don't know what that ends up calling:
>
>   /* Create the sum or difference.  */
>   if (resultcode == MINUS_EXPR)
>     intop = fold_build1 (NEGATE_EXPR, sizetype, intop);
>
>   ret = fold_build2 (POINTER_PLUS_EXPR, result_type, ptrop, intop);
>
> It's calling NEGATE on an unsigned type, which seems wrong to me.

NEGATE_EXPR on an unsigned type is fully defined.  It's what you
should get when you say "unsigned int i, j; ...; i = - j;".

I think the problem you are facing may be that POINTER_PLUS_EXPR
generally assumes that the right type to use to add to a pointer is
sizetype.  You may need to make it use a different type, though I'm
not sure what that type should be in your case.

Ian