Stefan Monnier via "Bug reports for GNU Emacs, the Swiss army knife of
text editors" <bug-gnu-emacs@gnu.org> writes:

> I installed a patch in `master` which should fix this problem, both for
> the case where the code is interpreted and for the case where it is
> byte-compiled.

Very good.

This seems to break some of my private code.  Didn't look into your
change so far.

My code generates function advices with the following semantics: You
specify an alternative function and a condition (as a predicate
function).  When the advice is enabled, whenever the function is called
the predicate is first checked for a non-nil result.  When non-nil, the
alternative function that had been specified is called (recursive calls
are bot affected however).  When nil, the original function is called.

I'm using this hack only in my init file for convenience, I like the
semantics for this purpose.

Here is a recipe for emacs -Q: