Reserve OP_SENDVK for the future keyword arguments like Ruby3.0.

include/mruby/ops.h

@@ -61,13 +61,14 @@ OPCODE(SENDV,      BB)       /* R(a) = call(R(a),Syms(b),*R(a+1)) */
 OPCODE(SENDVB,     BB)       /* R(a) = call(R(a),Syms(b),*R(a+1),&R(a+2)) */
 OPCODE(SEND,       BBB)      /* R(a) = call(R(a),Syms(b),R(a+1),...,R(a+c)) */
 OPCODE(SENDB,      BBB)      /* R(a) = call(R(a),Syms(b),R(a+1),...,R(a+c),&R(a+c+1)) */
+OPCODE(SENDVK,     BB)       /* R(a) = call(R(a),Syms(b),*R(a+1),**(a+2),&R(a+3)) # todo */
 OPCODE(CALL,       Z)        /* R(0) = self.call(frame.argc, frame.argv) */
 OPCODE(SUPER,      BB)       /* R(a) = super(R(a+1),... ,R(a+b+1)) */
 OPCODE(ARGARY,     BS)       /* R(a) = argument array (16=m5:r1:m5:d1:lv4) */
 OPCODE(ENTER,      W)        /* arg setup according to flags (23=m5:o5:r1:m5:k5:d1:b1) */
-OPCODE(KEY_P,      BB)       /* R(a) = kdict.key?(Syms(b))                      # todo */
-OPCODE(KEYEND,     Z)        /* raise unless kdict.empty?                       # todo */
-OPCODE(KARG,       BB)       /* R(a) = kdict[Syms(b)]; kdict.delete(Syms(b))    # todo */
+OPCODE(KEY_P,      BB)       /* R(a) = kdict.key?(Syms(b)) */
+OPCODE(KEYEND,     Z)        /* raise unless kdict.empty? */
+OPCODE(KARG,       BB)       /* R(a) = kdict[Syms(b)]; kdict.delete(Syms(b)) */
 OPCODE(RETURN,     B)        /* return R(a) (normal) */
 OPCODE(RETURN_BLK, B)        /* return R(a) (in-block return) */
 OPCODE(BREAK,      B)        /* break R(a) */

src/vm.c

@@ -2820,6 +2820,10 @@ RETRY_TRY_BLOCK:
       goto L_RAISE;
     }
 
+    CASE(OP_SENDVK, BB) {       /* not yet implemented */
+      NEXT;
+    }
+
     CASE(OP_STOP, Z) {
       /*        stop VM */
       CHECKPOINT_RESTORE(RBREAK_TAG_STOP) {