rsmith@ - could you please land this patch as I don't have a commit permission?
================ Comment at: lib/CodeGen/CGExpr.cpp:553-554 @@ +552,4 @@ + + // Skip Vptr checks when the pointer value is null. This is redundant if + // -fsanitize=null is used. + // FIXME: Add optional flags. ---------------- Richard Smith wrote: > Nit: lowercase 'v'. > > It'd be nice to expand on this a bit: a null pointer here is undefined > behavior, but if -fsanitize=null is not enabled, we don't want to change the > behavior of code in that case, so that the user doesn't have to fix all their > null pointer bugs before they can find their type mismatch bugs (which are > likely to be more serious). Thanks Richard for the comments! Let me change the patch as you suggested. I was confused on your comment in -fsanitize=null, which says "When performing a pointer downcast, it's OK if the value is null. Skip the remaining checks in that case". Is this mean that the down-casted null pointer is a result of "defined behavior", or did you mean something else? From my shallow understanding and your review comments, it seems "undefined" though. http://reviews.llvm.org/D4412 _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
