unsafep-variable

unsafep-variable is a compiled Lisp function in `unsafep.el'.

(unsafep-variable SYM TO-BIND)

Return nil if SYM is safe to set or bind, or a reason why not.
If TO-BIND is nil, check whether SYM is safe to set.
If TO-BIND is t, check whether SYM is safe to bind.