Clarify docstring of package-native-compile

* lisp/emacs-lisp/package.el (package-native-compile): Clarify
docstring.

1 files changed, 7 insertions, 1 deletions

diff --git a/lisp/emacs-lisp/package.el b/lisp/emacs-lisp/package.el
index 8fc54945d61..1387439f0ab 100644
--- a/lisp/emacs-lisp/package.el
+++ b/lisp/emacs-lisp/package.el
@@ -397,7 +397,13 @@ a sane initial value."
   :type '(repeat symbol))
 
 (defcustom package-native-compile nil
-  "Non-nil means to native compile packages on installation."
+  "Non-nil means to native compile packages after installing them.
+This controls ahead-of-time compilation.  If this option is nil,
+packages are normally compiled after they have been loaded for
+the first time.
+
+This option does not have any effect if Emacs was not built with
+native compilation support."
   :type '(boolean)
   :risky t
   :version "28.1")