* alloc.c (Fmake_byte_code): Don't access undefined argument (Bug#6517).

2 files changed, 6 insertions, 1 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 4d80761d7d6..5ba3f0e12a2 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2010-06-26  Andreas Schwab  <schwab@linux-m68k.org>
+
+        * alloc.c (Fmake_byte_code): Don't access undefined argument
+        (Bug#6517).
+
 2010-06-25  Chong Yidong  <cyd@stupidchicken.com>
 
         * xdisp.c (next_element_from_image): Ensure that after-strings are
diff --git a/src/alloc.c b/src/alloc.c
index 9a935cc8952..da63fe0f82b 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -3094,7 +3094,7 @@ usage: (make-byte-code ARGLIST BYTE-CODE CONSTANTS DEPTH &optional DOCSTRING INT
   else
     val = Fmake_vector (len, Qnil);
 
-  if (STRINGP (args[1]) && STRING_MULTIBYTE (args[1]))
+  if (nargs > 1 && STRINGP (args[1]) && STRING_MULTIBYTE (args[1]))
     /* BYTECODE-STRING must have been produced by Emacs 20.2 or the
        earlier because they produced a raw 8-bit string for byte-code
        and now such a byte-code string is loaded as multibyte while