# HG changeset patch
# User aidan
# Date 1188940826 0
# Node ID 8f6a825eb3d387286d92467ad386777932c01048
# Parent  08efedad2696fbe17e5c80c8bcef13e218ec2d8f
[xemacs-hg @ 2007-09-04 21:20:18 by aidan]
Eliminate a crash when profiling; only pass the backtrace record to
profile_record_about_to_call, profile_record_just_called when it's non-nil.

diff -r 08efedad2696 -r 8f6a825eb3d3 src/ChangeLog
--- a/src/ChangeLog	Mon Sep 03 21:51:09 2007 +0000
+++ b/src/ChangeLog	Tue Sep 04 21:20:26 2007 +0000
@@ -1,3 +1,16 @@
+2006-11-26  Aidan Kehoe  <kehoea@parhasard.net>
+
+	* eval.c (Fcommand_execute):
+	* eval.c (Feval):
+	* eval.c (Ffuncall):
+	Use the PROFILE_DECLARE macro instead of declaring `struct
+	backtrace backtrace' by hand. 
+	* profile.h:
+	* profile.h (PROFILE_EXIT_FUNCTION):
+	* profile.h (PROFILE_ENTER_FUNCTION):
+	Check do_backtrace before passing the backtrace structure to
+	profile_record_about_to_call, profile_record_just_called. 
+
 2007-08-28  Aidan Kehoe  <kehoea@parhasard.net>
 
 	* mule-ccl.c (ccl_driver):
diff -r 08efedad2696 -r 8f6a825eb3d3 src/eval.c
--- a/src/eval.c	Mon Sep 03 21:51:09 2007 +0000
+++ b/src/eval.c	Tue Sep 04 21:20:26 2007 +0000
@@ -3100,7 +3100,7 @@
   /* This function can GC */
   Lisp_Object prefixarg;
   Lisp_Object final = cmd;
-  struct backtrace backtrace;
+  PROFILE_DECLARE();
   struct console *con = XCONSOLE (Vselected_console);
 
   prefixarg = con->prefix_arg;
@@ -3533,7 +3533,7 @@
   /* This function can GC */
   Lisp_Object fun, val, original_fun, original_args;
   int nargs;
-  struct backtrace backtrace;
+  PROFILE_DECLARE();
 
 #ifdef ERROR_CHECK_TRAPPING_PROBLEMS
   check_proper_critical_section_lisp_protection ();
@@ -3841,7 +3841,7 @@
   /* This function can GC */
   Lisp_Object fun;
   Lisp_Object val;
-  struct backtrace backtrace;
+  PROFILE_DECLARE();
   int fun_nargs = nargs - 1;
   Lisp_Object *fun_args = args + 1;
 
diff -r 08efedad2696 -r 8f6a825eb3d3 src/profile.h
--- a/src/profile.h	Mon Sep 03 21:51:09 2007 +0000
+++ b/src/profile.h	Tue Sep 04 21:20:26 2007 +0000
@@ -47,11 +47,18 @@
    This ensures correct behavior (e.g. we never modify the profiling info
    when profiling is not active) because we seed and reap all functions
    currently on the stack when starting and stopping.  See
-   `start-profiling'. */
+   `start-profiling'.
+
+   We check do_backtrace to make sure that the backtrace structure is
+   initialised. If it isn't, we can enter a function with profiling turned
+   off, and exit it with it turned on, with the consequence that an
+   unitialised backtrace structure is passed to
+   profile_record_just_called. Since do_backtrace is function-local (apart
+   from in the garbage collector) this avoids that.  */
 #define PROFILE_ENTER_FUNCTION()		\
 do						\
 {						\
-  if (profiling_active)				\
+  if (profiling_active && do_backtrace)		\
     profile_record_about_to_call (&backtrace);	\
 }						\
 while (0)
@@ -59,7 +66,7 @@
 #define PROFILE_EXIT_FUNCTION()			\
 do						\
 {						\
-  if (profiling_active)				\
+  if (profiling_active && do_backtrace)		\
     profile_record_just_called (&backtrace);	\
 }						\
 while (0)