Author: jingham Date: Fri Dec 6 16:21:04 2013 New Revision: 196616 URL: http://llvm.org/viewvc/llvm-project?rev=196616&view=rev Log: Do a little more prevention against SBValues getting used after the world has been torn down around them.
Modified: lldb/trunk/source/API/SBValue.cpp Modified: lldb/trunk/source/API/SBValue.cpp URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/API/SBValue.cpp?rev=196616&r1=196615&r2=196616&view=diff ============================================================================== --- lldb/trunk/source/API/SBValue.cpp (original) +++ lldb/trunk/source/API/SBValue.cpp Fri Dec 6 16:21:04 2013 @@ -96,7 +96,24 @@ public: bool IsValid () { - return m_valobj_sp.get() != NULL; + if (m_valobj_sp.get() == NULL) + return false; + else + { + // FIXME: This check is necessary but not sufficient. We for sure don't want to touch SBValues whose owning + // targets have gone away. This check is a little weak in that it enforces that restriction when you call + // IsValid, but since IsValid doesn't lock the target, you have no guarantee that the SBValue won't go + // invalid after you call this... + // Also, an SBValue could depend on data from one of the modules in the target, and those could go away + // independently of the target, for instance if a module is unloaded. But right now, neither SBValues + // nor ValueObjects know which modules they depend on. So I have no good way to make that check without + // tracking that in all the ValueObject subclasses. + TargetSP target_sp = m_valobj_sp->GetTargetSP(); + if (target_sp && target_sp->IsValid()) + return true; + else + return false; + } } lldb::ValueObjectSP @@ -120,6 +137,8 @@ public: Target *target = value_sp->GetTargetSP().get(); if (target) api_locker.Lock(target->GetAPIMutex()); + else + return ValueObjectSP(); ProcessSP process_sp(value_sp->GetProcessSP()); if (process_sp && !stop_locker.TryLock (&process_sp->GetRunLock())) @@ -276,7 +295,7 @@ SBValue::IsValid () // If this function ever changes to anything that does more than just // check if the opaque shared pointer is non NULL, then we need to update // all "if (m_opaque_sp)" code in this file. - return m_opaque_sp.get() != NULL && m_opaque_sp->GetRootSP().get() != NULL; + return m_opaque_sp.get() != NULL && m_opaque_sp->IsValid() && m_opaque_sp->GetRootSP().get() != NULL; } void _______________________________________________ lldb-commits mailing list lldb-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/lldb-commits