[libcxx-dev] Should libc++ .fail.cpp tests use -verify?

[Mikhail Maltsev via libcxx-dev]

Hi all,

After the following commit

"commit 2fd7d364cd999c743b5bdefa7ee9e5630f3564ad
Author: Louis Dionne <ldionne at apple.com>
Date:   Mon Apr 27 12:49:01 2020 -0400

[libc++] Make the verify-support feature implicit

Tests that require support for Clang-verify are already marked as such
explicitly by their extension, which is .verify.cpp. Requiring the use
of an explicit Lit feature is, after thought, not really helpful.

This is a change in design: we have been bitten in the past by tests not
being enabled when we thought they were. However, the issue was mostly
with file extensions being ignored. The fix for that is not to blindly
require explicit features all the time, but instead to report all files
that are in the suite but that don't match any known test format. This
can be implemented in a follow-up patch."

All '.fail.cpp' started being run without the -verify command line 
option. This reduced test coverage: the test suite is now only checking 
that compilation of the .fail.cpp tests fails, but does not check the 
locations of the actual errors and warnings.

It this intentional? Just in case: we are using the 'use_old_format' lit 
feature because the new format does not support custom executors (e.g. 
simulators) yet.

-- 
Regards,
    Mikhail Maltsev