Linux lldb 3.8 hangs on live cores, update docs

[brendangregg]

I suspect we've hit this known and fixed bug with lldb 3.8:

• https://bugs.llvm.org//show_bug.cgi?id=26322
• https://reviews.llvm.org/rL287858

With a live core dump, lldb hangs:

# lldb -f /usr/bin/node -c /var/cores/core.node.30833
(lldb) target create "/usr/bin/node" --core "/var/cores/core.node.30833"
[...hang...]

Could the install instructions for Linux note this and the fix? Would the current fix be an lldb build from source, or is it packaged with the patch yet in lldb 3.8 or 3.9?

[brendangregg]

should have CC'd @hhellyer

[hhellyer]

I think it's only in the 4.0 branch. (There's a github mirror of the llvm project that's easier to search, I checked one of the files I updated here: https://github.com/llvm-mirror/lldb/blob/release_40/source/Plugins/Process/elf-core/ThreadElfCore.h)

Building from source is one option but it's not that quick (you need to build llvm, clang and lldb) but there are some Ubuntu packages available from:
http://apt.llvm.org/
that might save you the work.

[rnchamberlain]

Re gcore dumps and the hang fix in lldb 4.0 see also the follow-up comments on #61

[brendangregg]

thanks!