`toolchain/autoupdate_testdata.py --allow-check-fail` can now be used to
perform an autoupdate even if some `CARBON_CHECK`s are failing. What
this does will depend on how the toolchain behaves after the `CHECK`
failure, and of course there's no guarantees there, but this can be
useful if it's easier to debug the `CHECK` failure by looking at the
produced SemIR.
Internally, this uses `bazel build --config=non-fatal-checks`, which in
turn specifies a `--per_file_copt` for `check_internal.cpp`. The intent
here is that the rebuild required to enable or disable this mode is as
small as reasonably possible.
This mode is not compatible with `-c opt`, as it's important that check
failure calls are `[[noreturn]]` in `-c opt` mode.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Richard SmithandJon Ross-Perkins
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