Avoid crashes in 'describe-keymap' due to shadowing

* src/keymap.c (describe_vector): Handle shadowing by something
other than a symbol.  (Bug#62867)

1 files changed, 12 insertions, 7 deletions

diff --git a/src/keymap.c b/src/keymap.c
index efac410d317..7f5777c9251 100644
--- a/src/keymap.c
+++ b/src/keymap.c
@@ -3308,13 +3308,18 @@ describe_vector (Lisp_Object vector, Lisp_Object prefix, Lisp_Object args,
       if (this_shadowed)
         {
           SET_PT (PT - 1);
-          static char const fmt[] = "  (currently shadowed by `%s')";
-          USE_SAFE_ALLOCA;
-          char *buffer = SAFE_ALLOCA (sizeof fmt +
-                                      SBYTES (SYMBOL_NAME (shadowed_by)));
-          esprintf (buffer, fmt, SDATA (SYMBOL_NAME (shadowed_by)));
-          insert_string (buffer);
-          SAFE_FREE();
+          if (SYMBOLP (shadowed_by))
+            {
+              static char const fmt[] = "  (currently shadowed by `%s')";
+              USE_SAFE_ALLOCA;
+              char *buffer =
+                SAFE_ALLOCA (sizeof fmt + SBYTES (SYMBOL_NAME (shadowed_by)));
+              esprintf (buffer, fmt, SDATA (SYMBOL_NAME (shadowed_by)));
+              insert_string (buffer);
+              SAFE_FREE();
+            }
+          else  /* Could be a keymap, a lambda, or a keyboard macro.  */
+            insert_string ("  (currently shadowed)");
           SET_PT (PT + 1);
         }
     }