+#ifdef MAC_OS_X_VERSION_10_5
+#include <sys/_structs.h>
+#endif
+
+#ifdef MAC_OS_X_VERSION_10_5
+
+typedef struct __darwin_ucontext darwin_ucontext;
+typedef struct __darwin_mcontext64 darwin_mcontext;
+
+#define rip __rip
+#define rsp __rsp
+#define rbp __rbp
+#define rax __rax
+#define rbx __rbx
+#define rcx __rcx
+#define rdx __rdx
+#define rsi __rsi
+#define rdi __rdi
+#define r8 __r8
+#define r9 __r9
+#define faultvaddr __faultvaddr
+#define ss __ss
+#define es __es
+#define fs __fs
+
+#else
+
+typedef struct ucontext darwin_ucontext;
+typedef struct mcontext darwin_mcontext;
+
+#endif
+