Variable: debug-on-signal
debug-on-signal is a customizable variable defined in eval.c.
Value
nil
Documentation
Non-nil means call the debugger regardless of condition handlers.
Note that debug-on-error, debug-on-quit and friends
still determine whether to handle the particular condition.
Probably introduced at or before Emacs version 20.1.
Source Code
// Defined in /usr/src/emacs/src/eval.c
DEFVAR_LISP ("debug-on-signal", Vdebug_on_signal,
doc: /* Non-nil means call the debugger regardless of condition handlers.
Note that `debug-on-error', `debug-on-quit' and friends
still determine whether to handle the particular condition. */);