On Mon, Sep 29, 2014 at 5:24 PM, Konstantin Serebryany <konstantin.s.serebry...@gmail.com> wrote: > > 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.
So, if we switch to instrumentation to callbacks (which are not necessarily noreturn), -fsanitize-recover is the thing we plan to support? > > > > > 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? :) We can preserve the default behavior for each tool (no recovery for ASan, recovery for UBSan) unless recovery mode is explicitly specified. > > > -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 -- Alexey Samsonov, Mountain View, CA
