Use a new type [input_file] instead, which records the file's name and index
on the command line.
This allows fixing a bug in [UnparameterizedPrinter] where [List.sort] was
used with a non-transitive "ordering".

This should fix a problem encountered on (some versions of?) Windows,
where dynamic linking is not supported, hence #load fails.

This reverts commit 397d02c98b57f7e22925473871cf0e51ff031430.

declarations for symbols that are inlined away (and warning about
them, at the same time).

for unreachable symbols.

and %on_error_reduce declarations are well-kinded.

a parameterized symbol, make sure that the arguments refer to well-defined
symbols.

New function [Grammar.OnErrorReduce.compare], unused for now.

For now, these levels are unused.

so as to avoid OCaml's warning 41.