bug#30004: 27.0.50; call-interactively reads uninitialized memory

[Eli Zaretskii]

> From: Philipp Stephani <p.stephani2@gmail.com>
> Date: Sat, 06 Jan 2018 16:03:44 +0000
> Cc: 30004@debbugs.gnu.org
> 
> Eli Zaretskii <eliz@gnu.org> schrieb am Sa., 6. Jan. 2018 um 16:56 Uhr:
> 
>  > From: Philipp <p.stephani2@gmail.com>
>  > Date: Sat, 06 Jan 2018 12:31:51 +0100
>  >
>  > When passing a byte that would start a multibyte sequence,
>  > `call-interactively` uses STRING_CHAR without checking whether the
>  > entire multibyte sequence is actually part of the string.  For example:
>  >
>  > $ emacs -batch -nw -Q -eval '(call-interactively (lambda () (interactive 
> "\xFF")))'
>  > Invalid control letter ‘𿯾’ (#o775776, #x3fbfe) in interactive calling 
> string
> 
>  Thanks for catching this.  Does the patch below fix this?
> 
> Yes, with that patch Valgrind doesn't find any errors any more. 

Thanks, pushed to the emacs-26 branch.