DEVEL15-kreltime-20061021

DEVEL15-kreltime-20061021

FIXES 43551

kreltime-guard-against-null-tm-20060731 was apparently an
attempt to deal with the possibility of localtime() returning NULL by
using localtime_r instead, and zeroing the tm structure first. This has
two problems. First, localtime_r is not guaranteed to leave its output
buffer untouched or in a sane state in the event it is given invalid
input. More importantly, the second half of this delta fixed the build
on Windows (which apparently lacks localtime_r) at the expense of using
the wrong level of indirection on other platforms.

Simple is nice, but correct is important too. There is nothing wrong
with switching to localtime_r to avoid thread safety issues. However,
the correct fix for the anticipated problem was and is to check the
return value of localtime (or localtime_r), and if it is NULL, fill in
the ktime_date with suitable default values.

The attached patch does not implement the correct fix, but does fix the
double-indirection problem, so butc will again perform correctly instead
of crashing.

(cherry picked from commit e720779b7c8472a0d928b0e1429b476f073309aa)