Re: [Qemu-devel] Re: Fwd: Re: port-sparc/44389: awk failure during m4 installation with pkgsrc

[Blue Swirl <blauwirbel@gmail.com>]

On Tue, Jan 18, 2011 at 11:40 AM, Mateusz Loskot <mateusz@loskot.net> wrote:
> Blue Swirl <blauwirbel <at> gmail.com> writes:
>> Mateusz Loskot <mateusz <at> loskot.net> wrote:
>> > Hi,
>> >
>> > I emulate SPARC with NetBSD 5.0 installed and I've experienced a problem
>> > with pkgsrc installing one of packages.
>> > I submitted bug report to NetBSD team and received short response
>> > suggesting it is likely QEMU problem (see original message below).
>> >
>> > Shortly, the problem is that AWK throws "floating point exception"
>> > Here is the bug report with details:
>> >
>> > http://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=44389
>> >
>> > Given the nature of the problem, it "feels" the issue is unrelated to
>> > QEMU, but I'm not on position to judge the suggestion posted by NetBSD
>> > team is pointless.
>> >
>> > I have no idea how to isolate the problem on NetBSD, so I replied to
>> > NetBSD team asking:
>> > ===
>> > Could you suggest how to isolate the problem, find exact awk command
>> > causing the error, so I can debug it or forward to QEMU developers with
>> > details necessary to reproduce it?
>> > ===
>> >
>> > In the meantime, I thought I will attack qemu-devel hoping it may ring
>> > some bells here as well.
>> >
>> > Any ideas?
>>
>> It's entirely possible that the floating point support for Sparc can
>> be buggy, there have been a few fixes to softfloat recently for other
>> architectures.
>>
>> I'd check if NaN handling or floating point exception support works
>> correctly, regular programs don't use those. But a reproducible test
>> case is essential.
>
>
> I think I have managed to isolate reproducible test for this problem
> and it seems the issue is in NetBSD userland.
> See my last update to the problem reprot:
>
> http://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=44389
>
> Long story short, the problem boils down to the following command:
>
> # echo NaN | awk '{print "test"}'
> awk: floating point exception 8
>  source line number 1
>
> which interprets "NaN" as a number when it isn't asked to.

FYI: also this succeeds on 4.0:
$ echo NaN | awk '{print "test"}'
test