[patch, i386] Use read_memory_unsigned_integer to get address

[Yao Qi <yao@codesourcery.com>]

The address on i386 is unsigned, so we should use
read_memory_unsigned_integer to fetch address from memory.

OK to apply?

-- 
Yao (齐尧) 

	gdb/
	* i386-linux-nat.c (i386_linux_resume): Use read_memory_unsigned_integer
	to get address.
	* i386obsd-nat.c (i386obsd_supply_pcb): Likewise.

diff --git a/gdb/i386-linux-nat.c b/gdb/i386-linux-nat.c
index e32a119..6257931 100644
--- a/gdb/i386-linux-nat.c
+++ b/gdb/i386-linux-nat.c
@@ -893,7 +893,8 @@ i386_linux_resume (struct target_ops *ops,
 
 	      regcache_cooked_read_unsigned (regcache, I386_ESP_REGNUM, &sp);
 	      if (syscall == SYS_rt_sigreturn)
-		addr = read_memory_integer (sp + 8, 4, byte_order) + 20;
+		addr = read_memory_unsigned_integer (sp + 8, 4, byte_order)
+		  + 20;
 	      else
 		addr = sp;
 
diff --git a/gdb/i386obsd-nat.c b/gdb/i386obsd-nat.c
index db1f693..1c0d047 100644
--- a/gdb/i386obsd-nat.c
+++ b/gdb/i386obsd-nat.c
@@ -78,8 +78,8 @@ i386obsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
     {
       /* No, the pcb must have been last updated by savectx().  */
       pcb->pcb_esp = pcb->pcb_ebp;
-      pcb->pcb_ebp = read_memory_integer(pcb->pcb_esp, 4, byte_order);
-      sf.sf_eip = read_memory_integer(pcb->pcb_esp + 4, 4, byte_order);
+      pcb->pcb_ebp = read_memory_unsigned_integer (pcb->pcb_esp, 4, byte_order);
+      sf.sf_eip = read_memory_unsigned_integer (pcb->pcb_esp + 4, 4, byte_order);
       regcache_raw_supply (regcache, I386_EIP_REGNUM, &sf.sf_eip);
     }