* breakpoint.c (fetch_watchpoint_value): New function.

	(update_watchpoint): Set and clear val_valid.  Use
	fetch_watchpoint_value.  Handle unreadable values on the
	value chain.  Correct check for user-requested array watchpoints.
	(breakpoint_init_inferior): Clear val_valid.
	(watchpoint_value_print): New function.
	(print_it_typical): Use it.  Do not free or clear old_val.  Print
	watchpoints even if old_val == NULL.
	(watchpoint_check): Use fetch_watchpoint_value.  Check for values
	becoming readable or unreadable.
	(watch_command_1): Use fetch_watchpoint_value.  Set val_valid.
	(do_enable_watchpoint): Likewise.
	* breakpoint.h (struct breakpoint): Update comment for val.  Add
	val_valid.
	* NEWS: Mention watchpoints on inaccessible memory.

	* gdb.base/watchpoint.c (global_ptr, func4): New.
	(main): Call func4.
	* gdb.base/watchpoint.exp: Call test_inaccessible_watchpoint.
	(test_inaccessible_watchpoint): New.

	* gdb.texinfo (Set Watchpoints): Mention watchpoints on
	unreadable memory.  Delete obsolete SPARClite reference.

3 files changed, 45 insertions, 0 deletions

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 3886227..fc2a39c 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2008-03-03  Daniel Jacobowitz  <dan@codesourcery.com>
+
+	* gdb.base/watchpoint.c (global_ptr, func4): New.
+	(main): Call func4.
+	* gdb.base/watchpoint.exp: Call test_inaccessible_watchpoint.
+	(test_inaccessible_watchpoint): New.
+
 2008-02-29  Maciej W. Rozycki  <macro@mips.com>
 
 	* lib/gdb.exp (gdb_expect): Of all the timeouts provided always
diff --git a/gdb/testsuite/gdb.base/watchpoint.c b/gdb/testsuite/gdb.base/watchpoint.c
index 1a61ba1..bba97fa 100644
--- a/gdb/testsuite/gdb.base/watchpoint.c
+++ b/gdb/testsuite/gdb.base/watchpoint.c
@@ -39,6 +39,8 @@ struct foo struct1, struct2, *ptr1, *ptr2;
 
 int doread = 0;
 
+char *global_ptr;
+
 void marker1 ()
 {
 }
@@ -110,6 +112,14 @@ func1 ()
   return 73;
 }
 
+void
+func4 ()
+{
+  buf[0] = 3;
+  global_ptr = buf;
+  buf[0] = 7;
+}
+
 int main ()
 {
 #ifdef usestubs
@@ -185,5 +195,7 @@ int main ()
 
   func3 ();
 
+  func4 ();
+
   return 0;
 }
diff --git a/gdb/testsuite/gdb.base/watchpoint.exp b/gdb/testsuite/gdb.base/watchpoint.exp
index d27179d..3c20d10 100644
--- a/gdb/testsuite/gdb.base/watchpoint.exp
+++ b/gdb/testsuite/gdb.base/watchpoint.exp
@@ -645,6 +645,30 @@ proc test_watchpoint_and_breakpoint {} {
     }
 }
     
+proc test_inaccessible_watchpoint {} {
+    global gdb_prompt
+
+    # This is a test for watchpoints on currently inaccessible (but later
+    # valid) memory.
+
+    if [runto func4] then {
+	gdb_test "watch *global_ptr" ".*atchpoint \[0-9\]+: \\*global_ptr"
+	gdb_test "next" ".*global_ptr = buf.*"
+	gdb_test_multiple "next" "next over ptr init" {
+	    -re ".*atchpoint \[0-9\]+: \\*global_ptr\r\n\r\nOld value = .*\r\nNew value = 3 .*\r\n.*$gdb_prompt $" {
+		# We can not test for <unknown> here because NULL may be readable.
+		# This test does rely on *NULL != 3.
+		pass "next over ptr init"
+	    }
+	}
+	gdb_test_multiple "next" "next over buffer set" {
+	    -re ".*atchpoint \[0-9\]+: \\*global_ptr\r\n\r\nOld value = 3 .*\r\nNew value = 7 .*\r\n.*$gdb_prompt $" {
+		pass "next over buffer set"
+	    }
+	}
+    }
+}
+    
 # Start with a fresh gdb.
 
 gdb_exit
@@ -797,6 +821,8 @@ if [initialize] then {
       }
     }
 
+    test_inaccessible_watchpoint
+
     # See above.
     if [istarget "mips-idt-*"] then {
 	gdb_exit