bug#56553: 29.0.50; ASAN error with fringe bitmaps on NS

[Eli Zaretskii]

> From: Robert Pluim <rpluim@gmail.com>
> Cc: Eli Zaretskii <eliz@gnu.org>,  Po Lu <luangruo@yahoo.com>,
>   56553@debbugs.gnu.org
> Date: Fri, 15 Jul 2022 15:57:40 +0200
> 
> >>>>> On Fri, 15 Jul 2022 15:55:40 +0200, Gerd Möllmann 
> >>>>> <gerd.moellmann@gmail.com> said:
> 
>     >> On 2022-07-15,, at 12:37 , Eli Zaretskii <eliz@gnu.org> wrote:
>     >> 
>     >>> From: Gerd Möllmann <gerd.moellmann@gmail.com>
>     >>> Date: Fri, 15 Jul 2022 11:14:02 +0200
>     >>> Cc: Eli Zaretskii <eliz@gnu.org>,
>     >>> 56553@debbugs.gnu.org
>     >>> 
>     >>> 
>     >>>> On 2022-07-15,, at 10:23 , Po Lu <luangruo@yahoo.com> wrote:
>     >>> 
>     >>>> Yes, you're right here.  I think that code does want to access the
>     >>>> individual bytes.
>     >>> 
>     >>> Interestingly, just doing
>     >>> 
>     >>> const char *bitmap_bytes = (const char *) bits;
>     >>> bool bit = bitmap_bytes[byte] & (0x80 >> x % 8);
>     >>> 
>     >>> here results in garbage fringe bitmaps beign displayed.  I'm stumped.
>     >> 
>     >> Is the machine little-endian or big-endian?
> 
>     Gerd> Good question!  I think it's little-endian, but I'm not 100% sure. 
> 
> Both Intel and Arm based macs are little-endian

Then I guess my theory doesn't hold water?