bug#47378: Emacs 27.1 binary Mac OS build crashes on Big Sur (11.x)

[Alan Third]

On Wed, Mar 24, 2021 at 10:36:47PM -0700, Victor Tsaran wrote:
> Hi.
> I apologize for not submitting this using Emacs's bug reporting system, but
> I d not use Emacs for my emailing needs, thus do not have the right setup
> for doing this.
> I am attaching the full crash log from Mac OS generated by the system and
> hope it will be helpful in diagnosing the problem.
> More background information below.
> 
> 1. I am using the clean Mac OS build of Emacs 27.1 from the Cask repository
> of Homebrew.
> 2. The build runs without any issues on Mac OS Catalina (10.15) using exact
> same packages and exact same configuration.
> 3. Emacs seems to abort with memory allocation errors, see the crash thread.

I don't know what's going on here. It looks like a failure in
malloc...?

Thread 13 Crashed:
0   libsystem_kernel.dylib              0x00007fff20309002 __sigsuspend + 10
1   Emacs-x86_64-10_14                  0x00000001041868a8 
deliver_thread_signal + 120
2   Emacs-x86_64-10_14                  0x0000000104185309 
deliver_fatal_thread_signal + 9
3   libsystem_platform.dylib            0x00007fff2035fd7d _sigtramp + 29
4   libsystem_malloc.dylib              0x00007fff20144020 
tiny_malloc_from_free_list + 555
5   libsystem_c.dylib                   0x00007fff2026e72f abort + 135
6   libsystem_malloc.dylib              0x00007fff2014f430 malloc_vreport + 548
7   libsystem_malloc.dylib              0x00007fff201524c8 malloc_report + 151
8   Emacs-x86_64-10_14                  0x00000001040e5590 draw_glyphs + 16048
9   Emacs-x86_64-10_14                  0x000000010410547a expose_line + 666
10  Emacs-x86_64-10_14                  0x00000001040ed37f expose_window + 1263
11  Emacs-x86_64-10_14                  0x00000001040ece5b expose_window_tree + 
139
12  Emacs-x86_64-10_14                  0x00000001040eccd1 expose_frame + 113
13  Emacs-x86_64-10_14                  0x000000010428f6e5 -[EmacsView 
drawRect:] + 133

Is this a consistent crash or something that's just happened once?
-- 
Alan Third