Re: Line numbers reported by the byte compiler

[Richard Stallman]

    We could modify Fread to optionally return character positions in the
    stream of the components of the form it reads, perhaps by recursively
    substituting every form with (form . position), in the way
    Fread_from_string does.

The resulting Lisp object would be rather strange and not possible to
compile.  The byte compiler expects to get Lisp expressions.  It
sometimes has to evaluate those expressions.

Storing the correspondence in another place would work better.
The compiler could access it there.