[llvm-dev] Kill "KillTheDoctor"

[Michael Kruse via llvm-dev]

We still have the program called "KillTheDoctor" [1] in our source
tree. Its original intention was to stop requiring user interaction
for crashing regression tests under Windows (infamous Dr. Watson,
nowadays "[program] has stopped working" [2]), I don't think it is
useful anymore. It's also a very hacky approach, as admitted in the
source comment itself ("I hate Windows.")

I don't think it was the right approach in the first place. Today,
LLVM tools disable error reporting themselves [3,4].
SEM_NO­GP­FAULT­ERROR­BOX [5] can be passed when launching arbitrary
programs with error reporting disabled.

The only reference to it in the current source tree is compiler-rt [6]
and explicitly mentions it should be integrated with "not --crash".
However, it apparently already handles this case [7] and is already
used outside of compiler-rt, eg. [8]. Removing the special case for
Windows in [6] still passes the tests on my Windows machine (at least
check-asan and check-builtins).

Therefore, I propose to remove KillTheDoctor.

Michael

[1] https://github.com/llvm/llvm-project/tree/master/llvm/utils/KillTheDoctor
[2] https://www.ecosia.org/images?q=%22has+stopped+working%22
[3] https://github.com/llvm/llvm-project/blob/master/llvm/lib/Support/Windows/Signals.inc#L484
[4] https://github.com/llvm/llvm-project/blob/master/llvm/utils/unittest/UnitTestMain/TestMain.cpp#L38
[5] https://devblogs.microsoft.com/oldnewthing/20160204-00/?p=92972
[6] https://github.com/llvm/llvm-project/blob/master/compiler-rt/test/lit.common.cfg.py#L219
[7] https://github.com/llvm/llvm-project/blob/master/llvm/utils/not/not.cpp#L48
[8] https://github.com/llvm/llvm-project/blob/master/clang/test/Frontend/remove-file-on-signal.c#L2