Subject: bug#45515: 28.0.50; [feature/native-comp] emacsGcc crash on Apple Silicon M1

From: Andrea Corallo <[email-masked]>
Date: Tue, 29 Dec 2020 09:01:28 +0000

michal panoch <[email-masked]> writes:

> hi,
>
> i'm on the new Apple Silicon M1 architecture and using nix emacs-overlay - https://github.com/nix-community/emacs-overlay/
>
> like this: ~/.config/nixpkgs/overlays/emacs.nix
>
> import (builtins.fetchTarball {
>   url = https://github.com/nix-community/emacs-overlay/archive/master.tar.gz;
> })
>
> install whith:
>
> $ nix-env -iA nixpkgs.emacsGcc
>
> it compiles no problem. it runs and bytecompiles everything no problem, but after a while it crashes with:
>
> Assertion failed: (mach_vm_map(mach_task_self(), &address, size, 0, VM_FLAGS_ANYWHERE | VM_MAKE_TAG(VM_MEMORY_COREGRAPHICS_BACKINGSTORES), port, 0, false, prot, prot, VM_INHERIT_SHARE) == KERN_SUCCESS), function backing_map, file /AppleInternal/BuildRoot/Library/Caches/com.apple.xbs/Sources/SkyLight/SkyLight-569.6/SkyLight/Services/Windows/CGSBackingStore.c, line 192. Fatal error 6: Aborted [1] 2319 abort emacs --fg-daemon
>
> any idea how to investigate?
>
> uname -a:
> Darwin mpm.local 20.2.0 Darwin Kernel Version 20.2.0: Wed Dec  2 20:40:21 PST 2020; root:xnu-7195.60.75~1/RELEASE_ARM64_T8101 arm64

Hi Michal,

this assertion is out of our code so doesn't ring any bell to me.
Running under a debugger to have a back-trace of the crash might give
more information.

Thanks

  Andrea