1 files changed, 21 insertions, 14 deletions

diff --git a/src/lread.c b/src/lread.c
index 8b614e6220e..983fdb883ff 100644
--- a/src/lread.c
+++ b/src/lread.c
@@ -3523,25 +3523,32 @@ bytecode_from_rev_list (Lisp_Object elems, Lisp_Object readcharfun)
         }
     }
 
-  if (!(size >= CLOSURE_STACK_DEPTH + 1 && size <= CLOSURE_INTERACTIVE + 1
+  if (!(size >= CLOSURE_STACK_DEPTH && size <= CLOSURE_INTERACTIVE + 1
         && (FIXNUMP (vec[CLOSURE_ARGLIST])
             || CONSP (vec[CLOSURE_ARGLIST])
             || NILP (vec[CLOSURE_ARGLIST]))
-        && STRINGP (vec[CLOSURE_CODE])
-        && VECTORP (vec[CLOSURE_CONSTANTS])
-        && FIXNATP (vec[CLOSURE_STACK_DEPTH])))
+        && ((STRINGP (vec[CLOSURE_CODE]) /* Byte-code function.  */
+             && VECTORP (vec[CLOSURE_CONSTANTS])
+             && size > CLOSURE_STACK_DEPTH
+             && (FIXNATP (vec[CLOSURE_STACK_DEPTH])))
+            || (CONSP (vec[CLOSURE_CODE]) /* Interpreted function.  */
+                && (CONSP (vec[CLOSURE_CONSTANTS])
+                    || NILP (vec[CLOSURE_CONSTANTS]))))))
     invalid_syntax ("Invalid byte-code object", readcharfun);
 
-  if (STRING_MULTIBYTE (vec[CLOSURE_CODE]))
-    /* BYTESTR must have been produced by Emacs 20.2 or earlier
-       because it produced a raw 8-bit string for byte-code and
-       now such a byte-code string is loaded as multibyte with
-       raw 8-bit characters converted to multibyte form.
-       Convert them back to the original unibyte form.  */
-    vec[CLOSURE_CODE] = Fstring_as_unibyte (vec[CLOSURE_CODE]);
-
-  /* Bytecode must be immovable.  */
-  pin_string (vec[CLOSURE_CODE]);
+  if (STRINGP (vec[CLOSURE_CODE]))
+    {
+      if (STRING_MULTIBYTE (vec[CLOSURE_CODE]))
+        /* BYTESTR must have been produced by Emacs 20.2 or earlier
+           because it produced a raw 8-bit string for byte-code and
+           now such a byte-code string is loaded as multibyte with
+           raw 8-bit characters converted to multibyte form.
+           Convert them back to the original unibyte form.  */
+        vec[CLOSURE_CODE] = Fstring_as_unibyte (vec[CLOSURE_CODE]);
+
+      /* Bytecode must be immovable.  */
+      pin_string (vec[CLOSURE_CODE]);
+    }
 
   XSETPVECTYPE (XVECTOR (obj), PVEC_CLOSURE);
   return obj;