[all-commits] [llvm/llvm-project] fd37d4: Set error message if ValueObjectRegister fails to ...

[Ilya Nozhkin via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: fd37d489cfef3bf7d06b2b43dac2ad1381cdc56b
      https://github.com/llvm/llvm-project/commit/fd37d489cfef3bf7d06b2b43dac2ad1381cdc56b
  Author: Ilya Nozhkin <nozhkin.ii at gmail.com>
  Date:   2022-02-28 (Mon, 28 Feb 2022)

  Changed paths:
    M lldb/source/Core/ValueObjectRegister.cpp
    M lldb/test/API/functionalities/postmortem/elf-core/TestLinuxCore.py

  Log Message:
  -----------
  Set error message if ValueObjectRegister fails to write back to register

SetValueFromCString and SetData methods return false if register can't
be written but they don't set a error message. It sometimes confuses
callers of these methods because they try to get the error message in case of
failure but Status::AsCString returns nullptr.

For example, lldb-vscode crashes due to this bug if some register can't
be written. It invokes SBError::GetCString in case of error and doesn't
check whether the result is nullptr (see request_setVariable implementation in
lldb-vscode.cpp for more info).

Reviewed By: labath, clayborg

Differential Revision: https://reviews.llvm.org/D120319