$NetBSD: patch-ad,v 1.24 2013/05/29 11:11:12 wiz Exp $
--- mono/utils/mono-sigcontext.h.orig	2012-12-05 17:44:35.000000000 +0000
+++ mono/utils/mono-sigcontext.h
@@ -204,6 +204,10 @@ typedef struct ucontext {
 	#define UCONTEXT_REG_RSI(ctx) (((ucontext_t*)(ctx))->uc_mcontext.__gregs [_REG_RSI])
 	#define UCONTEXT_REG_RDI(ctx) (((ucontext_t*)(ctx))->uc_mcontext.__gregs [_REG_RDI])
 	#define UCONTEXT_REG_RIP(ctx) (((ucontext_t*)(ctx))->uc_mcontext.__gregs [_REG_RIP])
+	#define UCONTEXT_REG_R8(ctx) (((ucontext_t*)(ctx))->uc_mcontext.__gregs [_REG_R8])
+	#define UCONTEXT_REG_R9(ctx) (((ucontext_t*)(ctx))->uc_mcontext.__gregs [_REG_R9])
+	#define UCONTEXT_REG_R10(ctx) (((ucontext_t*)(ctx))->uc_mcontext.__gregs [_REG_R10])
+	#define UCONTEXT_REG_R11(ctx) (((ucontext_t*)(ctx))->uc_mcontext.__gregs [_REG_R11])
 	#define UCONTEXT_REG_R12(ctx) (((ucontext_t*)(ctx))->uc_mcontext.__gregs [_REG_R12])
 	#define UCONTEXT_REG_R13(ctx) (((ucontext_t*)(ctx))->uc_mcontext.__gregs [_REG_R13])
 	#define UCONTEXT_REG_R14(ctx) (((ucontext_t*)(ctx))->uc_mcontext.__gregs [_REG_R14])
@@ -292,7 +296,7 @@ typedef struct ucontext {
 	#define UCONTEXT_REG_FPRn(ctx, n) (((os_ucontext*)(ctx))->uc_mcontext.__fpregs.__fpu_regs [(n)])
 	#define UCONTEXT_REG_NIP(ctx)     _UC_MACHINE_PC(ctx)
 	#define UCONTEXT_REG_LNK(ctx)     (((os_ucontext*)(ctx))->uc_mcontext.__gregs [_REG_LR])
-#elif defined(__FreeBSD__)
+#elif defined(__FreeBSD__) || defined(__DragonFly__)
 	typedef ucontext_t os_ucontext;
 
 	#define UCONTEXT_REG_Rn(ctx, n)   ((ctx)->uc_mcontext.mc_gpr [(n)])