Conflate Qnil and Qunbound for `symbol-function'.

* src/alloc.c (Fmake_symbol): Initialize `function' to Qnil.
* src/lread.c (init_obarray): Set `function' fields to Qnil.
* src/eval.c (Fcommandp): Ignore Qunbound.
(Fautoload, eval_sub, Fapply, Ffuncall, Fmacroexpand):
* src/data.c (Ffset, Ffboundp, indirect_function, Findirect_function):
Test NILP rather than Qunbound.
(Ffmakunbound): Set to Qnil.
(Fsymbol_function): Never signal an error.
(Finteractive_form): Ignore Qunbound.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/lread.c b/src/lread.c
index 5859a2f85a9..6d0ff9f780e 100644
--- a/src/lread.c
+++ b/src/lread.c
@@ -3957,12 +3957,13 @@ init_obarray (void)
   /* Fmake_symbol inits fields of new symbols with Qunbound and Qnil,
      so those two need to be fixed manually.  */
   SET_SYMBOL_VAL (XSYMBOL (Qunbound), Qunbound);
-  set_symbol_function (Qunbound, Qunbound);
+  set_symbol_function (Qunbound, Qnil);
   set_symbol_plist (Qunbound, Qnil);
   SET_SYMBOL_VAL (XSYMBOL (Qnil), Qnil);
   XSYMBOL (Qnil)->constant = 1;
   XSYMBOL (Qnil)->declared_special = 1;
   set_symbol_plist (Qnil, Qnil);
+  set_symbol_function (Qnil, Qnil);
 
   Qt = intern_c_string ("t");
   SET_SYMBOL_VAL (XSYMBOL (Qt), Qt);