merges r21536 from trunk into ruby_1_9_1.

* vm.c (rb_vm_inc_const_missing_count, ruby_vm_const_missing_count):
  added.
* vm_insnhelper.h: ditto.
* variable.c (rb_const_get_0), insns.def: Constants should not be
  cached if const_missing is called.  [ruby-core:21059] [Bug #967]
* bootstraptest/test_class.rb: add a test.

git-svn-id: http://svn.ruby-lang.org/repos/ruby/branches/ruby_1_9_1@21574 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 8 insertions, 0 deletions

diff --git a/vm.c b/vm.c
index 2469d5ea4..b8b1fd2fd 100644
--- a/vm.c
+++ b/vm.c
@@ -34,6 +34,8 @@ VALUE rb_cEnv;
 VALUE rb_mRubyVMFrozenCore;
 
 VALUE ruby_vm_global_state_version = 1;
+VALUE ruby_vm_const_missing_count = 0;
+
 char ruby_vm_redefined_flag[BOP_LAST_];
 
 rb_thread_t *ruby_current_thread = 0;
@@ -49,6 +51,12 @@ rb_vm_change_state(void)
     INC_VM_STATE_VERSION();
 }
 
+void
+rb_vm_inc_const_missing_count(void)
+{
+    ruby_vm_const_missing_count +=1;
+}
+
 /* control stack frame */
 
 static inline VALUE