On Wed, Nov 06, 2013 at 04:23:06PM +0100, Richard Biener wrote:
> > In that case I think it would be fine to run the isolate paths
> > optimization, but to not omit the actual dereference of the NULL
> > pointer (possibly the dereference could be followed by a trap).
>
> Yeah, we need the trap to properly end the BB (even if that is a
> waste instruction generated).
BTW, why do we generate in this optimization __builtin_trap rather than
just __builtin_unreachable ()? The former still generates some code (abort,
some aborting instruction, ...), while the former is just an assertion that
valid code will not reach it.
Jakub
