CVS: strange test failures on FreeBSD - ideas sought

[Matthias Andree]

Hi,

on FreeBSD 4.9, running

        env BF_TEST_VERBOSE=1 gmake check TESTS=t.maildir\ t.MH

from a current CVS tree yields:

gmake[1]: Entering directory `/usr/home/emma/bogofilter-build/src/tests'
# 4039 words, 48 messages
# 1784 words, 21 messages
1c1
< good/cur/002 H 3.12916e-13
---
> good/cur/002 H 3.12972e-13
FAIL: t.maildir
1c1
< good/002 H 3.12916e-13
---
> good/002 H 3.12972e-13
FAIL: t.MH
===================
2 of 2 tests failed
===================

The difference between those figures is 5.6e-17, which is approximately
1/4 * DBL_EPSILON (2.22045e-16). Should we just quench values below
DBL_EPSILON to 0?

On SuSE Linux 8.2, everything's fine. I cannot currently test SPARC for
lack of formail(1). I don't see the difference between those machines at
the moment. GSL is not it, neither is GCC. I tried without GSL and with
GCC 2.95 on Linux.  FreeBSD runs on a K6-2/300 processor, Linux on a
Duron/700 -- either is IA32.

Any ideas as to what causes these mismatches? I was under the impression
K6-2/300 and Duron/700 were compatible, and the idea that Linux and
FreeBSD might behave differently in bogofilter is intimidating. If I'd
used some obscure, non-IEEE chip, I'd have had rounding policies to
blame, but in this case?

I must be missing something not quite obvious.

-- 
Matthias Andree

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