diff --git a/lopcodes.h b/lopcodes.h
index 6c9df6f3..683f8928 100644
--- a/lopcodes.h
+++ b/lopcodes.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lopcodes.h,v 1.152 2017/04/26 17:46:52 roberto Exp roberto $
+** $Id: lopcodes.h,v 1.153 2017/04/28 20:57:45 roberto Exp roberto $
 ** Opcodes for Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -106,6 +106,9 @@ enum OpMode {iABC, iABx, iAsBx, iAx};  /* basic instruction format */
 #define GETARG_C(i)	getarg(i, POS_C, SIZE_C)
 #define SETARG_C(i,v)	setarg(i, v, POS_C, SIZE_C)
 
+#define GETARG_Cr(i)	getarg(i, POS_C, SIZE_C - 1)
+#define GETARG_Ck(i)	getarg(i, (POS_C + SIZE_C - 1), 1)
+
 #define GETARG_Bx(i)	getarg(i, POS_Bx, SIZE_Bx)
 #define SETARG_Bx(i,v)	setarg(i, v, POS_Bx, SIZE_Bx)
 
diff --git a/lvm.c b/lvm.c
index cab599d0..1a7531e1 100644
--- a/lvm.c
+++ b/lvm.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lvm.c,v 2.276 2017/05/04 13:32:01 roberto Exp roberto $
+** $Id: lvm.c,v 2.277 2017/05/05 17:16:11 roberto Exp roberto $
 ** Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -737,9 +737,9 @@ void luaV_finishOp (lua_State *L) {
 #define RC(i)	check_exp(getCMode(GET_OPCODE(i)) == OpArgR, base+GETARG_C(i))
 #define KC(i)	check_exp(getCMode(GET_OPCODE(i)) == OpArgK, k+GETARG_C(i))
 #define RKB(i)	check_exp(getBMode(GET_OPCODE(i)) == OpArgK, \
-	(GETARG_Bk(i)) ? k+GETARG_Br(i) : base+GETARG_Br(i))
+	(GETARG_Bk(i)) ? k + GETARG_Br(i) : base + GETARG_Br(i))
 #define RKC(i)	check_exp(getCMode(GET_OPCODE(i)) == OpArgK, \
-	ISK(GETARG_C(i)) ? k+INDEXK(GETARG_C(i)) : base+GETARG_C(i))
+	(GETARG_Ck(i)) ? k + GETARG_Cr(i) : base + GETARG_Cr(i))