mruby-compiler: fix super with keyword arguments; fix #6659

allocate ** keyword dictionary register when methods have keyword
arguments (parse.y new_args_tail), broken in commit 26ea71260 during
cons-list to struct migration. reconstruct keyword hash after KEYEND
from extracted keyword local variables so super can access keyword
values. encode block parameter flag in ainfo bit 13 and generate
LOADNIL for block register in codegen_zsuper when parent has keywords
but no block parameter.

Co-authored-by: Claude <noreply@anthropic.com>

mrbgems/mruby-compiler/core/codegen.c

@@ -2373,11 +2373,12 @@ lambda_body(codegen_scope *s, node *locals, struct mrb_ast_args *args, node *bod
       | MRB_ARGS_KEY(ka, kd)
       | (ba ? MRB_ARGS_BLOCK() : 0);
     genop_W(s, OP_ENTER, a);
-    /* (12bits = 5:1:5:1) - Store argument counts for block argument passing (OP_BLKPUSH) */
+    /* (13bits = 6:1:5:1:1) - Store argument counts for block argument passing (OP_BLKPUSH) */
     s->ainfo = (((ma+oa) & 0x3f) << 7)
       | ((ra & 0x1) << 6)
       | ((pa & 0x1f) << 1)
-      | (ka || kd);
+      | (ka || kd)
+      | ((ba & 0x1) << 13);
 
     /* Optional argument default value initialization */
     pos = new_label(s); /* Start of the optional argument jump table. */
@@ -2453,6 +2454,45 @@ lambda_body(codegen_scope *s, node *locals, struct mrb_ast_args *args, node *bod
 
       if (has_keywords && !kwrest) { /* If there are keyword args but no keyword rest. */
         genop_0(s, OP_KEYEND); /* Signal end of keyword arguments. */
+
+        /* Reconstruct keyword hash for super to use */
+        /* After KEYEND, the hash at kw_pos is empty (all keys deleted by KARG) */
+        /* Build a fresh hash from the extracted keyword local variables */
+        int kw_dict_pos = ma + oa + ra + pa + 1;
+        int sp_save = cursp();
+
+        /* Load key-value pairs for each keyword argument starting at stack position */
+        node *kw_list = args->keyword_args;
+        int num_pairs = 0;
+        while (kw_list) {
+          node *kw = kw_list->car;
+          mrb_sym kw_sym = node_to_sym(kw->car);
+
+          /* Load symbol (key) */
+          genop_2(s, OP_LOADSYM, cursp(), new_sym(s, kw_sym));
+          push();
+
+          /* Load keyword local variable value */
+          genop_2(s, OP_MOVE, cursp(), lv_idx(s, kw_sym));
+          push();
+
+          num_pairs++;
+          kw_list = kw_list->cdr;
+        }
+
+        /* Create hash at current stack position, then move to keyword dict position */
+        if (num_pairs > 0) {
+          genop_2(s, OP_HASH, sp_save, num_pairs);
+          genop_2(s, OP_MOVE, kw_dict_pos, sp_save);
+        }
+        else {
+          /* No keyword args, create empty hash */
+          genop_2(s, OP_HASH, sp_save, 0);
+          genop_2(s, OP_MOVE, kw_dict_pos, sp_save);
+        }
+
+        /* Restore stack pointer */
+        s->sp = sp_save;
       }
     }
 
@@ -5326,8 +5366,10 @@ codegen_zsuper(codegen_scope *s, node *varnode, int val)
   uint16_t ainfo = 0;
   int n = CALL_MAXARGS;
   int sp = cursp();
+  mrb_bool has_block_arg = FALSE;
 
   push();        /* room for receiver */
+  int argary_pos = cursp();
   while (!s2->mscope) {
     lv++;
     s2 = s2->prev;
@@ -5335,16 +5377,21 @@ codegen_zsuper(codegen_scope *s, node *varnode, int val)
   }
   if (s2 && s2->ainfo > 0) {
     ainfo = s2->ainfo;
+    has_block_arg = (ainfo >> 13) & 0x1;
   }
   if (lv > 0xf) codegen_error(s, "too deep nesting");
   if (ainfo > 0) {
-    genop_2S(s, OP_ARGARY, cursp(), (ainfo<<4)|(lv & 0xf));
+    genop_2S(s, OP_ARGARY, argary_pos, (ainfo<<4)|(lv & 0xf));
     push(); push(); push();   /* ARGARY pushes 3 values at most */
     pop(); pop(); pop();
     /* keyword arguments */
     if (ainfo & 0x1) {
       n |= CALL_MAXARGS<<4;
       push();
+      /* If parent has keywords but no block parameter, ARGARY reads garbage for block */
+      if (!has_block_arg) {
+        genop_1(s, OP_LOADNIL, argary_pos+2);
+      }
     }
     /* block argument - tree here is args, so check for block */
     if (tree) {

mrbgems/mruby-compiler/core/parse.y

@@ -1089,7 +1089,7 @@ new_args_tail(parser_state *p, node *kws, mrb_sym kwrest, mrb_sym blk)
 {
   node *k;
 
-  if (kwrest) {
+  if (kws || kwrest) {
     local_add_kw(p, kwrest);
   }
 

mrbgems/mruby-compiler/core/y.tab.c

@@ -1151,7 +1151,7 @@ new_args_tail(parser_state *p, node *kws, mrb_sym kwrest, mrb_sym blk)
 {
   node *k;
 
-  if (kwrest) {
+  if (kws || kwrest) {
     local_add_kw(p, kwrest);
   }