[lldb-dev] Crashing thread from Core Dump

Karl Johan Krantz karl.johan.krantz at gmail.com
Tue Apr 21 00:51:06 PDT 2015

I am unfortunately not getting that behaviour out of lldb 330.0.44.

I'm running a small test file in order to try the behaviour out:

void threadTest(){
  int *a = nullptr;
  std::cout << *a << std::endl;

int main(){
  auto t = std::thread(threadTest);

  return 0;

If I then attach lldb to the generated core file, and run thread list I get
the following output
(lldb) thread list
Process 0 stopped
* thread #1: tid = 0x0000, 0x00007fff88cf648a
libsystem_kernel.dylib`__semwait_signal + 10, stop reason = signal SIGSTOP
  thread #2: tid = 0x0001, 0x000000010126624b test`threadTest() + 27, stop
reason = signal SIGSTOP

mån 20 apr. 2015 kl 19:01 skrev Greg Clayton <gclayton at apple.com>:

> > On Apr 18, 2015, at 1:11 PM, Karl Johan Krantz <
> karl.johan.krantz at gmail.com> wrote:
> >
> > Hi,
> >
> > I'm currently building a solution that parses stack traces from lldb
> into json, but I've run into the issue where I'm not able to find out which
> thread actually caused the crash itself.
> > In GDB, the default selected thread seems to be the one that crashed,
> but in LLDB it always seems like thread 1 is selected.
> > I had a feeling the python api might export the data I needed, but
> stop_reason and similar properties didn't seem to vary between the
> crashing/non-crashing threads.
> I am not sure we always know from a core file why things crashed. Is this
> information found in the ELF core file? It probably isn't. I don't think it
> is available in mach-o core files either.
> LLDB will always select the crashing thread if the thread had a stop
> reason. Let me know if this isn't happening. What does the output of:
> (lldb) thread list
> show? It should list all of the threads and their stop reasons, but again,
> I don't think core files contain the stop reasons for each thread so there
> is no way the ProcessElfCore plug-in can set the stop reason correctly.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/lldb-dev/attachments/20150421/a35aa7c9/attachment.html>

More information about the lldb-dev mailing list