On 11/11/13 02:33, Eric Botcazou wrote:
However, that brings up an couple interesting questions.
Let's say we find a NULL pointer which reaches a return statement in a
function which is marked as returns_nonnull. In that case there is no
dereference. Presumably for that kind of scenario we'll just keep the
builtin trap.
Similarly, assume we extend this pass to detect out-of-bounds array
indexing. It's fairly simple to do and has always been in my plan. In
that case leaving in the array indexing won't necessarily generate a
fault. For those presumably we'll just want the builtin_trap as well?
Again, I don't mind inserting a *0, I just want to have a plan for the
other undefined behaviours we currently detect and those which I plan on
catching soon.
The more general problem is that, with -fnon-call-exceptions, we really expect
a fully-fledged exception to be raised when something goes wrong. Inserting
__builtin_trap doesn't work because it's simply not equivalent to a throw. In
other words, if __builtin_throw would be inserted instead of __builtin_trap
with -fnon-call-exceptions, things would probably be acceptable as-is.
Hmm, maybe that's a better soultion then. When non-call-exceptions is
active, throw rather than trap.
Seems fairly reasonable.
Jeff
