Fix spurious "Lexical argument shadows the dynamic variable" due to inlining

Before this patch doing:

    rm lisp/calendar/calendar.elc
    make lisp/calendar/cal-hebrew.elc

would spew out lots of spurious such warnings about a `date` argument,
pointing to code which has no `date` argument in sight.  This was
because that code had calls to inlinable functions (taking a `date`
argument) defined in `calendar.el`, and while `date` is a normal
lexical var at the site of those functions' definitions, it was
declared as dynbound at the call site.

* lisp/emacs-lisp/byte-opt.el (byte-compile-inline-expand):
Don't impose our local context onto the inlined function.

* test/lisp/emacs-lisp/bytecomp-tests.el: Add matching test.

1 files changed, 4 insertions, 2 deletions

diff --git a/lisp/emacs-lisp/byte-opt.el b/lisp/emacs-lisp/byte-opt.el
index cfa407019a7..66a117fccc8 100644
--- a/lisp/emacs-lisp/byte-opt.el
+++ b/lisp/emacs-lisp/byte-opt.el
@@ -284,8 +284,10 @@
                           ;; If `fn' is from the same file, it has already
                           ;; been preprocessed!
                           `(function ,fn)
-                        (byte-compile-preprocess
-                         (byte-compile--reify-function fn)))))
+                        ;; Try and process it "in its original environment".
+                        (let ((byte-compile-bound-variables nil))
+                          (byte-compile-preprocess
+                           (byte-compile--reify-function fn))))))
            (if (eq (car-safe newfn) 'function)
                (byte-compile-unfold-lambda `(,(cadr newfn) ,@(cdr form)))
              ;; This can happen because of macroexp-warn-and-return &co.