The backtrace is not very informative, in this case ?? ??:0 w32_backtrace at w32fns.c:9289 emacs_abort at w32fns.c:9321 terminate_due_to_signal at emacs.c:398 handle_fatal_signal at sysdep.c:1591 deliver_thread_signal at sysdep.c:1565 deliver_fatal_thread_signal at sysdep.c:1603 ?? at cygming-crtbegin.c:? ?? ??:0 ?? ??:0 ?? ??:0 and I don't get a crash with that recipe using the same binary.