-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 11/07/11 06:53, Tom Tromey wrote: >>>>>> "Jeff" == Jeff Law <l...@redhat.com> writes: > > Jeff> First, it's perfectly fine to have a NULL pointer dereference > in a Jeff> program as long as that code is never executed. Once > the code is Jeff> executed, we've entered the realm of undefined > behavior. > > Jeff> Thus in a conforming program we can safely assume that a > provable NULL Jeff> pointer dereference can never be executed at > runtime. This implies Jeff> there is a path through the CFG that > is unexecutable. > > IIUC, then this isn't true for Java. In Java the attempt to > dereference NULL throws a NullPointerException, which can be > caught, etc. It isn't undefined. So, presumably there's no way to know we're throwing to NullPointerException from the exception information attached to the statement or BB? If not I could disable if the statement with the memory op throws anywhere. It's not ideal, but conservatively correct.
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