bug#26364: [PATCH] Handle possible NULL return value of tzalloc.

[Paul Eggert]

Pádraig Brady wrote:
> A quick scan shows that functions using tz handle the NULL case,
> falling back to default behavior.

Yes, when I wrote that code I assumed that users prefer getting UTC time stamps 
to getting a diagnostic and no time stamps. That's the Unix tradition for other 
tz setting failures, e.g., TZ='no-such-time-zone'. If my assumption is wrong and 
users prefer an error message when memory is low, the patch would make sense. 
It's low priority, though, as the behavior is well-defined whether or not the 
patch is installed.