Paul Eggert <eggert@cs.ucla.edu> schrieb am So., 11. Juni 2017 um 19:45 Uhr:

> Philipp Stephani wrote:
> > Here's a new patch. It makes this change, and also changes the allocation
> > slightly so that objects have unique addresses (useful for checking).
>
> Thanks for working on this. Some comments.
>
> Have you looked into the runtime overhead of this approach, assuming
> -module-assertions is not specified? Currently lisp_to_value and
> value_to_lisp
> typically  are optimized away (i.e., zero machine instructions), and that
> wouldn't be true under the proposed patch even when -module-assertions is
> not
> used. Granted, module calls need not be super-fast, but it might be nice to
> avoid the overhead in the typical case if that is easy.
>

I've run a simple benchmark (5000000 iterations of mod-test-sum). Result
for the base case (module assertions not compiled) is 4.602 seconds, with
the new code it's 4.605 seconds. That's probably good enough.


>
> What happens if -module-assertions is enabled for Emacs, Emacs dumps
> itself, and
> -module-assertions is not enabled when the dumped Emacs is run?


Good question. I've now just made -module-assertions during dumping an
error.


> Or vice versa.
>

That's the normal case, which should work just fine.


>
> Are the FOR_EACH_TAIL_SAFE macro calls needed? This macro is needed only
> for
> lists that might be circular (e.g., the lists are available to Lisp code,
> which
> can call setcdr on their components). If the calls are not needed I
> suggest just
> an ordinary for loop.
>

Done.


>
> A small point: the FOR_EACH... loops should be indented like ordinary
> for-loops.
>

Done. (Would be great if CC-Mode knew about this.)