vm.c: fix up r58012

* vm.c (invoke_iseq_block_from_c): fix stack region length.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58014 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

vm.c

@@ -998,7 +998,7 @@ invoke_iseq_block_from_c(rb_thread_t *th, const struct rb_captured_block *captur
     th->passed_bmethod_me = NULL;
 
     CHECK_VM_STACK_OVERFLOW(cfp, argc);
-    cfp->sp = sp + i;
+    cfp->sp = sp + argc;
     for (i=0; i<argc; i++) {
 	sp[i] = argv[i];
     }