srhines added a comment. In https://reviews.llvm.org/D47894#1125728, @jyknight wrote:
> In https://reviews.llvm.org/D47894#1125653, @efriedma wrote: > > > The problem would come from propagating nonnull-ness from something which > > isn't inherently nonnull. For example, strlen has a nonnull argument, so > > `strlen(NULL)` is UB, therefore given `int z = strlen(x); if (x) {...}`, we > > can remove the null check. (Not sure we actually do this transform at the > > moment, but it's something we could do in the future.) > > > I think the question there is actually whether we need to, in addition to > supporting null pointer dereference, also cause all > `__attribute__((nonnull))` annotations at the C/C++ level to be ignored. > > And, yes, I believe we should. Is that what the kernel community actually wants though? There are certainly others who want a way to strip `__attribute__((nonnull))` completely, which seems a bit orthogonal to the removal of null checks in general. I think it would be good to support such a flag, but the presence of `nonnull` inside kernel sources leads me to believe they want those cases to be treated specially. Repository: rC Clang https://reviews.llvm.org/D47894 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
