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

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

[Mateusz Loskot]

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?

Mateusz

-------- Original Message --------
Subject: Re: port-sparc/44389: awk failure during m4 installation with
pkgsrc
Date: Fri, 14 Jan 2011 19:45:01 +0000 (UTC)
From: Martin Husemann <martin@duskware.de>
Reply-To: gnats-bugs@NetBSD.org
To:
port-sparc-maintainer@netbsd.org,gnats-admin@netbsd.org,netbsd-bugs@netbsd.org,mateusz@loskot.net

The following reply was made to PR port-sparc/44389; it has been noted
by GNATS.

From: Martin Husemann <martin@duskware.de>
To: gnats-bugs@NetBSD.org
Cc: port-sparc-maintainer@netbsd.org, gnats-admin@netbsd.org,
	netbsd-bugs@netbsd.org
Subject: Re: port-sparc/44389: awk failure during m4 installation with
pkgsrc
Date: Fri, 14 Jan 2011 20:43:44 +0100

 On Fri, Jan 14, 2011 at 05:45:01PM +0000, mateusz@loskot.net wrote:
 > /usr/bin/awk: floating point exception 8
 >  input record number 18792, file configure
 >  source line number 1
 > *** Error code 2

 My bet would be a qemu bug.

 Martin

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

[Blue Swirl]

On Fri, Jan 14, 2011 at 9:41 PM, Mateusz Loskot <mateusz@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.

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

[Mateusz Loskot]

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.

Best regards,
-- 
Mateusz Loskot, http://mateusz.loskot.net
Charter Member of OSGeo, http://osgeo.org
Member of ACCU, http://accu.org

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

[Blue Swirl]

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