Re: interrupt causes parse error in configure script

[Jim Meyering]

Ralf Wildenhues <address@hidden> wrote:

> * Jim Meyering wrote on Mon, Aug 18, 2008 at 11:57:45PM CEST:
>> Ralf Wildenhues <address@hidden> wrote:
>> >> I think we can factor it into a simpler testcase.  I just tried this:
>> >>
>> >> $ sh -c 'if test `sleep 5; echo hi` = hi ; then echo yes; fi'
>> >
>> > and found only pdksh and OpenBSD sh (which is a pdksh descendant) to
>> > have this issue.
>>
>> I'm pretty sure this happened with recent bash on my primary desktop
>> system.  You can reproduce it with any shell like this:
>>
>>     if test `sleep 5 && echo f` = f; then echo yes; fi
>>
>> Then kill the sleep process in under 5 seconds.  I get parse
>> errors from the latest versions of bash, dash, and zsh.
>
> Indeed.
>
>> So this *can* happen with other shells, if either the eval or
>> the $as_echo from the expansion of AS_VAR_GET fails.
>> Admittedly, this isn't the same as a simple ^C, so maybe
>> there's a race condition somewhere in there and the signal
>> has to hit a small window... or maybe it did happen on
>> some other type of system.
>
> Looks like it.
>
> Luckily parse errors don't seem to happen with
>   case `sleep 5 && echo f` in ...
>   for x in `sleep 5 && echo f`; do ...
>
> (better: I can't reproduce them with that, with a number of shells),
> which means the number of currently known-problematic places in Autoconf
> code is quite small, I found one in status.m4 and one in the test suite.

Good catches.

> This is what I've got now.  Thoughts?
>
> I'm pretty sure that any remaining test failure I'm seeing are not
> introduced by this patch, so if you are ok with it I'll apply.

Looks fine to me.  BTW, I too am seeing a few test failures,
but they're triggered even without this change.

Thanks!