[PATCH] msvcrt: Don't crash if _vsnwprintf gets NULL as format string

[Fabian Maurer]

On Sonntag, 1. Oktober 2017 23:22:19 CEST Marvin wrote:
> Hi,
> 
> While running your changed tests on Windows, I think I found new failures.
> Being a bot and all I'm not very good at pattern recognition, so I might be
> wrong, but could you please double-check?
> Full results can be found at
> https://testbot.winehq.org/JobDetails.pl?Key=33350
> 
> Your paranoid android.
> 
> 
> === wxppro (32 bit printf) ===
> 09e8:printf: unhandled exception c0000005 at 77C431F7
> 
> === w2003std (32 bit printf) ===
> 05f0:printf: unhandled exception c0000005 at 77BD4190


Welp, XP seems to behave different, I'll need to rework that.

Regards,
Fabian Maurer