Re: [PATCH v2 1/5] cmake: make it easier to diagnose regressions in CTest runs

From: Eric Sunshine <ericsunshine@gmail.com>
Date: Sep 28, 2022, 06:55 UTC
Message-ID: <CAPig+cQTxVvBtKymLeWkDtRSBqejjydP6o-PfDriQHP-M+cShg@mail.gmail.com>
In-Reply-To: <220908.86illyl3yo.gmgdl@evledraar.gmail.com>

On Thu, Sep 8, 2022 at 3:28 AM Ævar Arnfjörð Bjarmason <avarab@gmail.com> wrote:

Show 21 quoted lines

> On Tue, Aug 23 2022, Johannes Schindelin via GitGitGadget wrote:
> > When a test script fails in Git's test suite, the usual course of action
> > is to re-run it using options to increase the verbosity of the output,
> > e.g. `-v` and `-x`.
> > [...]
> > Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> > ---
> > diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
> > +             COMMAND ${SH_EXE} ${tsh} --no-bin-wrappers --no-chain-lint -vx
>
> I think the "--no-bin-wrappers --no-chain-lint" and the "while at it"
> here should be stripped out, and put into its own commit.
>
> So, perhaps we should have a performance hack due to Windows's slowness,
> but:
>
>  C. Since I sent [1] we've had submitted chainlint.pl in-flight
>     series. It's partly trying to take special considerations to be fast
>     on Windows. I don't think it's the case with that series that this
>     needs to be skipped on Windows anymore (and if it is, Eric would
>     like to know).

I had the opportunity to test chainlint.pl on an 8-core machine using both Linux and Windows 10. The machine is more than a few years old, though not nearly as old as my own development machine. Although chainlint.pl checked all test definitions in the entire project in less than one _second_ on Linux, it took two _minutes_ on Windows 10 on the same machine (using all 8 cores). Despite the fact that Perl is run just once to check all test definitions -- unlike chainlint.sed running 'sed' tens of thousands of times, chainlint.pl is still painfully slow on Windows, so I certainly understand the desire to use --no-chain-lint, at least on Windows.