2 files changed, 11 insertions, 3 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 0049b350f44..43d5caa4eaf 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,9 @@
+2008-08-27  Chong Yidong  <cyd@stupidchicken.com>
+
+        * eval.c (find_handler_clause): Temporarily increase
+        max-lisp-eval-depth while printing the backtrace buffer, to
+        guarantee that help-mode code can run.
+
 2008-08-27  Eli Zaretskii  <eliz@gnu.org>
 
         * msdos.c (Fmsdos_remember_default_colors): Don't reverse frame
diff --git a/src/eval.c b/src/eval.c
index 083cea889f5..6531b977990 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -1941,16 +1941,18 @@ find_handler_clause (handlers, conditions, sig, data)
     {
       if (!NILP (sig) && wants_debugger (Vstack_trace_on_error, conditions))
         {
+          max_lisp_eval_depth += 15;
           max_specpdl_size++;
-    #ifdef PROTOTYPES
+#ifdef PROTOTYPES
           internal_with_output_to_temp_buffer ("*Backtrace*",
                                                (Lisp_Object (*) (Lisp_Object)) Fbacktrace,
                                                Qnil);
-    #else
+#else
           internal_with_output_to_temp_buffer ("*Backtrace*",
                                                Fbacktrace, Qnil);
-    #endif
+#endif
           max_specpdl_size--;
+          max_lisp_eval_depth -= 15;
         }
 
       if (!debugger_considered)