[all-commits] [llvm/llvm-project] 81cc5d: Don't assume that __cxa_current_exception_type exi...

[jimingham via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 81cc5d1c7d3f7292e82e8611fcd4a2889278a218
      https://github.com/llvm/llvm-project/commit/81cc5d1c7d3f7292e82e8611fcd4a2889278a218
  Author: Jim Ingham <jingham at apple.com>
  Date:   2019-11-01 (Fri, 01 Nov 2019)

  Changed paths:
    M lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp

  Log Message:
  -----------
  Don't assume that __cxa_current_exception_type exists.

Normally you shouldn't be able to have a process with an ItaniumABI plugin
that doesn't have this symbol.  But if the loader crashes before loading
libc++abi.dylib (on MacOS), then the symbol might not be present.  So we
should check before accessing the pointer.

There isn't a good way to write a test for this, but the change is obvious.