diff --git a/src/alloc.c b/src/alloc.c
index 68bee7728c..61ce002a3f 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -6833,21 +6833,28 @@ sweep_symbols (void)
 
       for (; sym < end; ++sym)
         {
-          if (!sym->s.gcmarkbit)
+          if (sym->s.function != Vdead)
             {
-              if (sym->s.redirect == SYMBOL_LOCALIZED)
-                xfree (SYMBOL_BLV (&sym->s));
-              sym->s.next = symbol_free_list;
-              symbol_free_list = &sym->s;
-              symbol_free_list->function = Vdead;
-              ++this_free;
+              if (!sym->s.gcmarkbit)
+                {
+                  if (sym->s.redirect == SYMBOL_LOCALIZED)
+                    xfree (SYMBOL_BLV (&sym->s));
+                  sym->s.next = symbol_free_list;
+                  symbol_free_list = &sym->s;
+                  symbol_free_list->function = Vdead;
+                  ++this_free;
+                }
+              else
+                {
+                  ++num_used;
+                  sym->s.gcmarkbit = 0;
+                  /* Attempt to catch bogus objects.  */
+                  eassert (valid_lisp_object_p (sym->s.function));
+                }
             }
           else
             {
-              ++num_used;
-              sym->s.gcmarkbit = 0;
-              /* Attempt to catch bogus objects.  */
-              eassert (valid_lisp_object_p (sym->s.function));
+              eassert (!sym->s.gcmarkbit);
             }
         }