master d1341ef3f0d: * lisp/subr.el (derived-mode-p): Disable warnings for old convention

[Stefan Monnier]

branch: master
commit d1341ef3f0d7f2e64d26791ea41c752feef3fd3c
Author: Stefan Monnier <monnier@iro.umontreal.ca>
Commit: Stefan Monnier <monnier@iro.umontreal.ca>

    * lisp/subr.el (derived-mode-p): Disable warnings for old convention
---
 lisp/subr.el | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lisp/subr.el b/lisp/subr.el
index 7f2dcdc4d90..7b52f4f68f9 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -2804,7 +2804,11 @@ MODES should be a list of symbols or a single mode 
symbol instead of a list.
 We also still support the deprecated calling convention:
 \(derived-mode-p &rest MODES)."
  (declare (side-effect-free t)
-          (advertised-calling-convention (modes) "30.1"))
+          ;; FIXME: It's cumbersome for external packages to write code which
+          ;; accommodates both the old and the new calling conventions *and*
+          ;; doesn't cause spurious warnings.  So let's be more lenient
+          ;; for now and maybe remove `deprecated-args' for Emacs-31.
+          (advertised-calling-convention (modes &rest deprecated-args) "30.1"))
  (provided-mode-derived-p major-mode (if old-modes (cons modes old-modes)
                                        modes)))