1 files changed, 1 insertions, 0 deletions

diff --git a/src/data.c b/src/data.c
index c0c797da266..02249a887fa 100644
--- a/src/data.c
+++ b/src/data.c
@@ -719,6 +719,7 @@ determined by DEFINITION.  */)
      (symbol, definition, docstring)
      register Lisp_Object symbol, definition, docstring;
 {
+  CHECK_SYMBOL (symbol);
   if (CONSP (XSYMBOL (symbol)->function)
       && EQ (XCAR (XSYMBOL (symbol)->function), Qautoload))
     LOADHIST_ATTACH (Fcons (Qt, symbol));