I'll change it to an assert and next time it happens I'll dig a little more. I've only seen this on about 1 or 2 out of 100 runs of the test suite so I don't know how it happens.
On Fri, Nov 13, 2015 at 1:44 PM Jim Ingham <jing...@apple.com> wrote: > GetCurrentPlan should never return NULL. The Thread constructor pushes > the Base thread plan onto the stack, and pop won't remove the Base plan. > When we destroy the thread (in ThreadDestroy) we clear the plan stack and > then push a ThreadPlanNull onto the plan stack. So if you are seeing a > GetCurrentPlan returning NULL that means somebody is using it while it is > in the process of being created or destroyed. The former shouldn't be > possible, so you must be accessing it while it is in mid-destroy. > > I'd rather not put more code in various places that checks for things that > should never be true, or if you are doing this check you should assert so > we can figure out how this is happening. > > Note, ThreadDestroy doesn't lock itself against uses of the thread. That > hasn't been necessary but if you are seeing crashes here, it might be worth > doing that. > > Jim > > > > On Nov 13, 2015, at 1:28 PM, Zachary Turner via lldb-commits < > lldb-commits@lists.llvm.org> wrote: > > > > Author: zturner > > Date: Fri Nov 13 15:28:53 2015 > > New Revision: 253086 > > > > URL: http://llvm.org/viewvc/llvm-project?rev=253086&view=rev > > Log: > > Add a null check against the ThreadPlan > > > > I'm seeing some cases where the ThreadPlan is null. It could > > be a sign of a valid race condition, but at least we shouldn't > > crash. > > > > Modified: > > lldb/trunk/source/Target/ThreadList.cpp > > > > Modified: lldb/trunk/source/Target/ThreadList.cpp > > URL: > http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Target/ThreadList.cpp?rev=253086&r1=253085&r2=253086&view=diff > > > ============================================================================== > > --- lldb/trunk/source/Target/ThreadList.cpp (original) > > +++ lldb/trunk/source/Target/ThreadList.cpp Fri Nov 13 15:28:53 2015 > > @@ -538,7 +538,7 @@ ThreadList::WillResume () > > > > for (pos = m_threads.begin(); pos != end; ++pos) > > { > > - if ((*pos)->GetResumeState() != eStateSuspended && > > + if ((*pos)->GetResumeState() != eStateSuspended && > (*pos)->GetCurrentPlan() && > > (*pos)->GetCurrentPlan()->StopOthers()) > > { > > if ((*pos)->IsOperatingSystemPluginThread() && > !(*pos)->GetBackingThread()) > > > > > > _______________________________________________ > > lldb-commits mailing list > > lldb-commits@lists.llvm.org > > http://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits > >
_______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
