[m-rev.] for review: remove exceptions from the second half of recompilation.check.m

[Julien Fischer]

On Tue, 20 Apr 2021, Zoltan Somogyi wrote:

> Check for recompilation reasons without exceptions.
> 
> compiler/recompilation.check.m:
>     Make the code that checks whether a module need to be recompiled
>     do its work without using exceptions. Instead of throwing an exception
>     when we find a reason that the module under consideration needs to be
>     recompiled, we return it as a "stopping reason". Code executed later
>     whose task would normally be to look for other reasons will simply
>     not look if a stopping reason has already been found. (Unless the
>     flag for finding all reasons is set, in which case we keep going
>     to find other reasons in exactly the same set of circumstances
>     in which the old code used to avoid throwing an exception.)

That's fine.

Julien.