* lisp/emacs-lisp/eieio-core.el (eieio-oset-default): Catch the unexpected

case where the default value would be re-interpreted as a form!

2 files changed, 7 insertions, 0 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 9ca0c306e44..d9024982807 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,8 @@
+2015-02-09  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+        * emacs-lisp/eieio-core.el (eieio-oset-default): Catch the unexpected
+        case where the default value would be re-interpreted as a form!
+
 2015-02-09  Christopher Genovese  <genovese@cmu.edu>  (tiny change)
 
         * help-fns.el (help-fns--signature): Keep doc for keymap.
diff --git a/lisp/emacs-lisp/eieio-core.el b/lisp/emacs-lisp/eieio-core.el
index fa8fefa1df0..e71c54d4123 100644
--- a/lisp/emacs-lisp/eieio-core.el
+++ b/lisp/emacs-lisp/eieio-core.el
@@ -1010,6 +1010,8 @@ Fills in the default value in CLASS' in SLOT with VALUE."
           (signal 'invalid-slot-name (list (eieio--class-symbol class) slot)))
       (eieio--validate-slot-value class c value slot)
       ;; Set this into the storage for defaults.
+      (if (eieio-eval-default-p value)
+          (error "Can't set default to a sexp that gets evaluated again"))
       (setcar (nthcdr (- c (eval-when-compile eieio--object-num-slots))
                       (eieio--class-public-d class))
               value)