Re: Crash during access_keymap

[Richard M. Stallman]

    I meant a kind of analysis to ensure that any literals inside a
    function are not modified.

I don't quite follow.  If they are pure, they cannot be modified; the
primitives that would do so will signal an error.  Unless they have
bugs.

    To detect the case that the contents of the pure storage are changed
    accidentally.  It actually occurred when I tried preloading
    international/encoded-kb.elc.  Maybe CHECK_IMPURE should be added to
    Fccl_execute_on_string?

If that function can modify a string, it must call CHECK_IMPURE.
On a system where "pure" space really is read-only, trying to 
modify it would cause an immediate crash--good for debugging, but
not an elegant way to report the problem.