From 7768312c1da6a021ffb72529e55b960aa9335923 Mon Sep 17 00:00:00 2001
From: nobu <nobu@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Sat, 18 Mar 2017 11:29:35 +0000
Subject: [PATCH] vm.c: guard arguments [EXPERIMENTAL]

* vm.c (invoke_iseq_block_from_c): guard arguments on stack, not
  to be clobbered during splatting.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58012 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 vm.c            | 2 ++
 vm_insnhelper.c | 4 ++++
 2 files changed, 6 insertions(+)

diff --git a/vm.c b/vm.c
index 70df6707b8..74ca28c5c7 100644
--- a/vm.c
+++ b/vm.c
@@ -998,12 +998,14 @@ 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;
     for (i=0; i<argc; i++) {
 	sp[i] = argv[i];
     }
 
     opt_pc = vm_yield_setup_args(th, iseq, argc, sp, passed_block_handler,
 				 (type == VM_FRAME_MAGIC_LAMBDA ? (splattable ? arg_setup_lambda : arg_setup_method) : arg_setup_block));
+    cfp->sp = sp;
 
     if (me == NULL) {
 	return invoke_block(th, iseq, self, captured, cref, type, opt_pc);
diff --git a/vm_insnhelper.c b/vm_insnhelper.c
index a991e59562..695567ff21 100644
--- a/vm_insnhelper.c
+++ b/vm_insnhelper.c
@@ -2506,7 +2506,11 @@ vm_callee_setup_block_arg_arg0_check(VALUE *argv)
 {
     VALUE ary, arg0 = argv[0];
     ary = rb_check_array_type(arg0);
+#if 0
     argv[0] = arg0;
+#else
+    VM_ASSERT(argv[0] == arg0);
+#endif
     return ary;
 }