diff --git a/sim_defs.h b/sim_defs.h
index 2290a199..8c536357 100644
--- a/sim_defs.h
+++ b/sim_defs.h
@@ -315,6 +315,21 @@ typedef uint32          t_addr;
 #define SIM_NOINLINE
 #endif
 
+/* Packed structure support */
+
+#ifdef _MSC_VER
+# define PACKED_BEGIN __pragma( pack(push, 1) )
+# define PACKED_END __pragma( pack(pop) )
+#else
+# define PACKED_BEGIN
+#if defined(_WIN32)
+# define PACKED_END __attribute__((gcc_struct, packed))
+#else
+# define PACKED_END __attribute__((packed))
+#endif
+#endif
+
+
 /* Storage class modifier for weak link definition for sim_vm_init() */
 
 #if defined(__cplusplus)
diff --git a/slirp/ip.h b/slirp/ip.h
index a4768a5c..0edcd361 100644
--- a/slirp/ip.h
+++ b/slirp/ip.h
@@ -62,15 +62,12 @@ typedef uint32_t n_long;                 /* long as received from the net */
 #ifdef _MSC_VER
 # define PACKED_BEGIN __pragma( pack(push, 1) )
 # define PACKED_END __pragma( pack(pop) )
-# define QEMU_PACKED
 #else
 # define PACKED_BEGIN
 #if defined(_WIN32)
 # define PACKED_END __attribute__((gcc_struct, packed))
-# define QEMU_PACKED __attribute__((gcc_struct, packed))
 #else
 # define PACKED_END __attribute__((packed))
-# define QEMU_PACKED __attribute__((packed))
 #endif
 #endif