On Mon, Sep 29, 2014 at 4:26 PM, Alexey Samsonov <samso...@google.com> wrote: > On Mon, Sep 29, 2014 at 4:17 PM, Jakub Jelinek <ja...@redhat.com> wrote: >> On Mon, Sep 29, 2014 at 03:36:20PM -0700, Alexey Samsonov wrote: >>> -fasan-recover doesn't look like a good idea - for instance, in Clang, we >>> never use "?san" >>> in flag names, preferring -fsanitize-whatever. What's the rationale behind >>> splitting >>> -fsanitize-recover in two flags (ASan- and UBSan- specific)? >>> Is there no way to keep a single -f(no-)sanitize-recover for that purpose? >>> Now it works >>> only for UBSan checks, but we may extend it to another sanitizers as well. >> >> The problem is that if we start using it for ASan, it needs to have a >> different default, because ASan wants to abort by default, while UBSan >> recover by default. -fsanitize=kernel-address w (KASan) wants to recover >> by default. So, the option is either to never support recover for >> -fsanitize=address, for ubsan keep -fsanitize-recover (by default) as is >> and for kasan use that same switch, or have separate flags. >> >> Jakub > > I don't think we ever going to support recovery for regular ASan > (Kostya, correct me if I'm wrong).
I hope so too. Another point is that with asan-instrumentation-with-call-threshold=0 (instrumentation with callbacks) we can and probably will allow to recover from errors (glibc demands that), but that does not require any compile-time flag. > I see no problem in enabling -fsanitize-recover by default for > -fsanitize=undefined and This becomes more interesting when we use asan and ubsan together. Which default setting is stronger? :) > -fsanitize=kernel-address. We can, potentially, extend > -fsanitize-recover flag to take the same values as -fsanitize= one, > so that one can specify which sanitizers are recoverable, and which > are not, but I'd try to make this a last resort - this is too complex. > > -- > Alexey Samsonov, Mountain View, CA