* top.h (lim_at_start): Declare.

* main.c (captured_main): Set it.
        * top.c (lim_at_start): Define.
        (command_loop): Use it instead of &environ.
        * event-top.c (command_handler): Likewise.

        * gdb.base/selftest.exp: Next over lim_at_start initialization.

gdb/ChangeLog

@@ -1,3 +1,11 @@
+2003-06-02  Richard Henderson  <rth@redhat.com>
+
+	* top.h (lim_at_start): Declare.
+	* main.c (captured_main): Set it.
+	* top.c (lim_at_start): Define.
+	(command_loop): Use it instead of &environ.
+	* event-top.c (command_handler): Likewise.
+
 2003-06-01  Jason Thorpe  <thorpej@wasabisystems.com>
 
 	* mipsnbsd-tdep.c: Update copyright years.

gdb/event-top.c

@@ -492,10 +492,8 @@ command_handler (char *command)
   if (display_space)
     {
 #ifdef HAVE_SBRK
-      extern char **environ;
       char *lim = (char *) sbrk (0);
-
-      space_at_cmd_start = (long) (lim - (char *) &environ);
+      space_at_cmd_start = lim - lim_at_start;
 #endif
     }
 
@@ -538,9 +536,8 @@ command_handler (char *command)
       if (display_space)
 	{
 #ifdef HAVE_SBRK
-	  extern char **environ;
 	  char *lim = (char *) sbrk (0);
-	  long space_now = lim - (char *) &environ;
+	  long space_now = lim - lim_at_start;
 	  long space_diff = space_now - space_at_cmd_start;
 
 	  printf_unfiltered ("Space used: %ld (%c%ld for this command)\n",
@@ -577,9 +574,8 @@ command_line_handler_continuation (struct continuation_arg *arg)
   if (display_space)
     {
 #ifdef HAVE_SBRK
-      extern char **environ;
       char *lim = (char *) sbrk (0);
-      long space_now = lim - (char *) &environ;
+      long space_now = lim - lim_at_start;
       long space_diff = space_now - space_at_cmd_start;
 
       printf_unfiltered ("Space used: %ld (%c%ld for this command)\n",

gdb/main.c

@@ -168,6 +168,10 @@ captured_main (void *data)
   /* This needs to happen before the first use of malloc.  */
   init_malloc (NULL);
 
+#ifdef HAVE_SBRK
+  lim_at_start = (char *) sbrk (0);
+#endif
+
 #if defined (ALIGN_STACK_ON_STARTUP)
   i = (int) &count & 0x3;
   if (i != 0)

gdb/testsuite/ChangeLog

@@ -1,3 +1,7 @@
+2003-06-02  Richard Henderson  <rth@redhat.com>
+
+	* gdb.base/selftest.exp: Next over lim_at_start initialization.
+
 2003-06-02  Richard Henderson  <rth@redhat.com>
 
 	* gdb.base/dump.exp [alpha*-*-*]: Add -taso linker switch.

gdb/testsuite/gdb.base/selftest.exp

@@ -115,6 +115,10 @@ proc do_steps_and_nexts {} {
 		set description "next over init_malloc and everything it calls"
 		set command "next"
 	    }
+	    -re ".*lim_at_start.*$gdb_prompt $" {
+		set description "next over lim_at_start initialization"
+		set command "next"
+	    }
 	    -re ".*count . 0x3.*$gdb_prompt $" {
 		set description "next over conditional stack alignment code 1"
 		set command "next"

gdb/top.c

@@ -171,6 +171,11 @@ int target_executing = 0;
 /* Level of control structure.  */
 static int control_level;
 
+/* Sbrk location on entry to main.  Used for statistics only.  */
+#ifdef HAVE_SBRK
+char *lim_at_start;
+#endif
+
 /* Signal to catch ^Z typed while reading a command: SIGTSTP or SIGCONT.  */
 
 #ifndef STOP_SIGNAL
@@ -782,10 +787,8 @@ command_loop (void)
       if (display_space)
 	{
 #ifdef HAVE_SBRK
-	  extern char **environ;
 	  char *lim = (char *) sbrk (0);
-
-	  space_at_cmd_start = (long) (lim - (char *) &environ);
+	  space_at_cmd_start = lim - lim_at_start;
 #endif
 	}
 
@@ -805,9 +808,8 @@ command_loop (void)
       if (display_space)
 	{
 #ifdef HAVE_SBRK
-	  extern char **environ;
 	  char *lim = (char *) sbrk (0);
-	  long space_now = lim - (char *) &environ;
+	  long space_now = lim - lim_at_start;
 	  long space_diff = space_now - space_at_cmd_start;
 
 	  printf_unfiltered ("Space used: %ld (%c%ld for this command)\n",

gdb/top.h

@@ -70,5 +70,6 @@ extern char *source_error;
 extern char *source_pre_error;
 extern int history_expansion_p;
 extern int server_command;
+extern char *lim_at_start;
 
 #endif