misc/44767: floating point support broken in QEMU

[Jukka Ruohonen <jruohonen%iki.fi@localhost>]

>Number:         44767
>Category:       misc
>Synopsis:       floating point support broken in QEMU
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    misc-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Mar 25 04:20:00 +0000 2011
>Originator:     Jukka Ruohonen
>Release:        NetBSD 5.1_STABLE
>Organization:
-
>Environment:
>Description:

This was caught by automated test runs [1]. In NetBSD x86_64 guest under QEMU:

        floor(16.999989) = 17.

Presumably such a fundamental error either causes or implies other serious
floating point bugs in QEMU. Remarks:

        (a) This does not fail on i386 NetBSD QEMU guest.

        (b) This does not fail on "native" i386 or amd64 NetBSD.

Given (b), I am inclined to think that this is a bug in QEMU, but I don't
know it well enough to draw an actual conclusion.

>How-To-Repeat:

[1] http://www.whooppee.com/~paul/amd64-results/1334_atf.html

>Fix:

Unknown.