[PATCH obv] Darwin: Fix gdb compilation.

[Bernhard Heckel <bernhard.heckel@intel.com>]

Due to changes introduced by
commit 4d01a485d29732b19743e8b138897f3509e071b0
('struct expression *' -> gdb::unique_xmalloc_ptr<expression>)
compilation is broken on Darwin.

../gdb/darwin-nat-info.c:733:8: error: assigning to 'struct expression *'
from incompatible type
'expression_up' (aka 'std::__1::unique_ptr<expression, gdb::xfree_deleter<expression> >')
expr = parse_expression (exp);

2016-12-16  Bernhard Heckel  <bernhard.heckel@intel.com>

gdb/Changelog:
	* darwin-nat-info.c (info_mach_region_command): Use expression_up.

---
 gdb/darwin-nat-info.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/gdb/darwin-nat-info.c b/gdb/darwin-nat-info.c
index 314d265..0262026 100644
--- a/gdb/darwin-nat-info.c
+++ b/gdb/darwin-nat-info.c
@@ -725,13 +725,12 @@ info_mach_regions_recurse_command (char *args, int from_tty)
 static void
 info_mach_region_command (char *exp, int from_tty)
 {
-  struct expression *expr;
   struct value *val;
   mach_vm_address_t address;
   struct inferior *inf;
 
-  expr = parse_expression (exp);
-  val = evaluate_expression (expr);
+  expression_up expr = parse_expression (exp);
+  val = evaluate_expression (expr.get ());
   if (TYPE_CODE (value_type (val)) == TYPE_CODE_REF)
     {
       val = value_ind (val);
-- 
2.7.1.339.g0233b80