Assert that function cells contain valid lisp objects

2 files changed, 10 insertions, 0 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index b2a8f81f3a6..f3cc322636c 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,11 @@
 2014-04-03  Daniel Colascione  <dancol@dancol.org>
 
+        * alloc.c (sweep_symbols,mark_object): Assert that symbol function
+        cells contain valid lisp objects.  (Modified version of patch from
+        Dmitry).
+
+2014-04-03  Daniel Colascione  <dancol@dancol.org>
+
         * alloc.c (detect_suspicious_free): Split actual stack capturing
         out into new function for easier breakpoint setting.
         (note_suspicious_free): New function.
diff --git a/src/alloc.c b/src/alloc.c
index 7c63fa05ac6..a007a43457d 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -6174,6 +6174,8 @@ mark_object (Lisp_Object arg)
           break;
         CHECK_ALLOCATED_AND_LIVE (live_symbol_p);
         ptr->gcmarkbit = 1;
+        /* Attempt to catch bogus objects.  */
+        eassert (valid_lisp_object_p (ptr->function) >= 1);
         mark_object (ptr->function);
         mark_object (ptr->plist);
         switch (ptr->redirect)
@@ -6601,6 +6603,8 @@ sweep_symbols (void)
               if (!pure_p)
                 eassert (!STRING_MARKED_P (XSTRING (sym->s.name)));
               sym->s.gcmarkbit = 0;
+              /* Attempt to catch bogus objects.  */
+              eassert (valid_lisp_object_p (sym->s.function) >= 1);
             }
         }