[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