Re: emacs-26 c87d04e: Avoid aborts in 'md5'

[Eli Zaretskii]

> From: Andreas Schwab <address@hidden>
> Cc: address@hidden,  Eli Zaretskii <address@hidden>
> Date: Wed, 28 Feb 2018 10:15:04 +0100
> 
> > See bug#30627.
> 
> So the CHECK_STRING should be put in the else branch.

In general, safe code should check STRINGP before using SSDATA, so the
way I did it is safer (and also more future-proof).

> There is also a useless CHECK_BUFFER in the BUFFERP branch.

Indeed.