x86_emulate: Shuffle use of __attribute__((packed))

Also include #defines for the test code to allow compilation.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Keir Fraser <keir@xen.org>
Reviewed-by: Jan Beulich <jbeulich@suse.com>

tools/tests/x86_emulator/test_x86_emulator.c

@@ -7,6 +7,8 @@
 #include <xen/xen.h>
 #include <sys/mman.h>
 
+#define __packed __attribute__((packed))
+
 #include "x86_emulate/x86_emulate.h"
 #include "blowfish.h"
 

tools/tests/x86_emulator/x86_emulate.c

@@ -14,5 +14,7 @@ typedef bool bool_t;
 #define cpu_has_amd_erratum(nr) 0
 #define mark_regs_dirty(r) ((void)(r))
 
+#define __packed __attribute__((packed))
+
 #include "x86_emulate/x86_emulate.h"
 #include "x86_emulate/x86_emulate.c"

xen/arch/x86/x86_emulate/x86_emulate.h

@@ -55,7 +55,7 @@ enum x86_segment {
  * Attribute for segment selector. This is a copy of bit 40:47 & 52:55 of the
  * segment descriptor. It happens to match the format of an AMD SVM VMCB.
  */
-typedef union segment_attributes {
+typedef union __packed segment_attributes {
     uint16_t bytes;
     struct
     {
@@ -69,18 +69,18 @@ typedef union segment_attributes {
         uint16_t g:   1;    /* 11; Bit 55 */
         uint16_t pad: 4;
     } fields;
-} __attribute__ ((packed)) segment_attributes_t;
+} segment_attributes_t;
 
 /*
  * Full state of a segment register (visible and hidden portions).
  * Again, this happens to match the format of an AMD SVM VMCB.
  */
-struct segment_register {
+struct __packed segment_register {
     uint16_t   sel;
     segment_attributes_t attr;
     uint32_t   limit;
     uint64_t   base;
-} __attribute__ ((packed));
+};
 
 /*
  * Return codes from state-accessor functions and from x86_emulate().