Suppress warning about pi not having a prefix

* lisp/emacs-lisp/float-sup.el (pi): Suppress warning about this
obsolete variable not having a prefix.

Author: larsmagne

lisp/emacs-lisp/float-sup.el

@@ -28,8 +28,9 @@
 ;; Provide an easy hook to tell if we are running with floats or not.
 ;; Define pi and e via math-lib calls (much less prone to killer typos).
 (defconst float-pi (* 4 (atan 1)) "The value of Pi (3.1415926...).")
-(defconst pi float-pi
-  "Obsolete since Emacs-23.3.  Use `float-pi' instead.")
+(with-suppressed-warnings ((lexical pi))
+  (defconst pi float-pi
+    "Obsolete since Emacs-23.3.  Use `float-pi' instead."))
 (internal-make-var-non-special 'pi)
 
 (defconst float-e (exp 1) "The value of e (2.7182818...).")