On Tue, Jan 9, 2018 at 3:16 AM, Nicolas Petton <nicolas@petton.fr> wrote:

>> - un-deprecate when-let (and if-let) in Emacs 26 and re-deprecate it
>>   later.
>
> I'm facing the same issue, un-deprecating when-let would also make my CI
> happier.

How about adding a variable which suppresses deprecation warnings from
a specified version and up. Attached is a work-in-progress patch which
would allow you to set byte-compile-not-obsolete-since to "25.1" in
your CI script (or file-locally) and thus ignore deprecation warnings
from 26.1 or newer.

Alternatively, or additionally, we could let
`byte-compile-not-obsolete-funcs' apply to macros as well (currently
macroexp-macroexpand doesn't consult it).