[PATCH] Fix memory-region overlapping checking

[Wei-cheng Wang <cole945@gmail.com>]

Hi,

  After adding a memory-region with <hi addr> as max CORE_ADDR+1,
  no more memory-region can be added. It always complains about "overlapping"

  For example,

(gdb) mem 0x50 0x80 ro
(gdb) mem 0xffffff00 0x100000000 ro
(gdb) info mem
Using user-defined memory regions.
Num Enb Low Addr   High Addr  Attrs
1   y   0x00000050 0x00000080 ro nocache
2   y   0xffffff00 0x100000000 ro nocache
(gdb) mem 0x100 0x200 ro
overlapping memory region

   When checking whether the new memory-region includes a previous one,
   it should take care special case, where hi == 0 means max CORE_ADDR+1.

Wei-cheng

2012-08-02  Wei-cheng Wang  <cole945@gmail.com>

	* memattr.c (create_mem_region): Fix memory-region overlapping checking
	in special case.

diff --git a/gdb/memattr.c b/gdb/memattr.c
--- a/gdb/memattr.c
+++ b/gdb/memattr.c
@@ -207,7 +207,7 @@ create_mem_region (CORE_ADDR lo, CORE_ADDR hi,

       if ((lo >= n->lo && (lo < n->hi || n->hi == 0))
 	  || (hi > n->lo && (hi <= n->hi || n->hi == 0))
-	  || (lo <= n->lo && (hi >= n->hi || hi == 0)))
+	  || (lo <= n->lo && ((hi >= n->hi && n->hi != 0) || hi == 0)))
 	{
 	  printf_unfiltered (_("overlapping memory region\n"));
 	  return;