Re: [PATCH 1/1] tests: teach the test-tool to generate NUL bytes and use it

From: Junio C Hamano <gitster@pobox.com>
Date: Feb 15, 2019, 17:41 UTC
Message-ID: <xmqq5ztl6jbj.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <nycvar.QRO.7.76.6.1902151558080.45@tvgsbejvaqbjf.bet>

Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:

Show 24 quoted lines

> On Thu, 14 Feb 2019, Junio C Hamano wrote:
>
>> "Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com>
>> writes:
>> 
>> > From: Johannes Schindelin <johannes.schindelin@gmx.de>
>> >
>> > In cc95bc2025 (t5562: replace /dev/zero with a pipe from
>> > generate_zero_bytes, 2019-02-09), we replaced usage of /dev/zero (which
>> > is not available on NonStop, apparently) by a Perl script snippet to
>> > generate NUL bytes.
>> >
>> > Sadly, it does not seem to work on NonStop, as t5562 reportedly hangs.
>> > ...
>> > In the end, though, what counts is that this here change incidentally
>> > fixes that hang (maybe also on NonStop?). Even more positively, it gets
>> > rid of yet another unnecessary Perl invocation.
>> 
>> Thanks for a quick band-aid.
>> 
>> Will apply directly to 'master' so that we won't forget before -rc2.
>
> Thank you, that will be good, as the builds still seem to fail. All of
> them.

Actually, I am really tempted to instead not apply this, but revert that genzerobytes Perl thing. This assumes that your Azure thing did not have the breakage before we applied that patchset. What do you think?

Trying four or more possible band-aids that may or may not work without knowing what the real cause of the hangs are is not something I want to see people spend excessive time of theirs on this close to the final. I'd rather avoid distraction and see people spend their cycles on bugs that matter, instead of trying to chase test breakages that have always been present for those without /dev/zero. I am not fundamentally opposed to supporting those without /dev/zero but I'd prefer to see it happen in 'pu' until we identify and fix the real cause---which may well be a real bug in the http-backend stuff---and the time to do that is not during the rc period where we close the tree for new features and non-regression fixes.