Hello,

As suggested here http://permalink.gmane.org/gmane.emacs.help/94196 I
attach a patch to make (defun ...) check that the arglist is an actual
list of symbols when defining a function, and otherwise signal an error.

Without this, code like (defun test-foobar ...) succeeds although the
function is doomed to fail at runtime.

This won't catch every missing "arglist" but that looks impossible
anyway.