1 files changed, 7 insertions, 2 deletions

diff --git a/src/bytecode.c b/src/bytecode.c
index 639c543dbf9..464bc3d12de 100644
--- a/src/bytecode.c
+++ b/src/bytecode.c
@@ -51,7 +51,7 @@ by Hallvard:
  *
  * define BYTE_CODE_METER to enable generation of a byte-op usage histogram.
  */
-/* #define BYTE_CODE_SAFE  1 */
+/* #define BYTE_CODE_SAFE */
 /* #define BYTE_CODE_METER */
 
 
@@ -1720,8 +1720,13 @@ exec_byte_code (Lisp_Object bytestr, Lisp_Object vector, Lisp_Object maxdepth,
           break;
 #endif
 
+        case 0:
+          /* Actually this is Bstack_ref with offset 0, but we use Bdup
+             for that instead.  */
+          /* case Bstack_ref: */
+          abort ();
+
           /* Handy byte-codes for lexical binding.  */
-          /* case Bstack_ref: */  /* Use `dup' instead.  */
         case Bstack_ref+1:
         case Bstack_ref+2:
         case Bstack_ref+3: