merge revision(s) 54542,54548: [Backport #12082]

	* compile.c (iseq_optimize): disable tail call optimization in
	  rescued, rescue, and ensure blocks.
	  [ruby-core:73871] [Bug #12082]

	* compile.c (new_label_body): initialize bit fields, since
	  compile_data_alloc does not clear the memory.  [Bug #12082]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_2@54698 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 41 insertions, 0 deletions

diff --git a/test/ruby/test_optimization.rb b/test/ruby/test_optimization.rb
index 91b46cc98c..8e350547f3 100644
--- a/test/ruby/test_optimization.rb
+++ b/test/ruby/test_optimization.rb
@@ -210,6 +210,23 @@ class TestRubyOptimization < Test::Unit::TestCase
     assert_equal true, MyObj.new == nil
   end
 
+  def self.tailcall(klass, src, file = nil, path = nil, line = nil)
+    unless file
+      loc, = caller_locations(1, 1)
+      file = loc.path
+      line ||= loc.lineno
+    end
+    RubyVM::InstructionSequence.new("proc {|_|_.class_eval {#{src}}}",
+                                    file, (path || file), line,
+                                    tailcall_optimization: true,
+                                    trace_instruction: false)
+      .eval[klass]
+  end
+
+  def tailcall(*args)
+    self.class.tailcall(singleton_class, *args)
+  end
+
   def test_tailcall
     bug4082 = '[ruby-core:33289]'
 
@@ -255,6 +272,30 @@ class TestRubyOptimization < Test::Unit::TestCase
     assert_equal(123, delay { 123 }.call, bug6901)
   end
 
+  def do_raise
+    raise "should be rescued"
+  end
+
+  def errinfo
+    $!
+  end
+
+  def test_tailcall_inhibited_by_rescue
+    bug12082 = '[ruby-core:73871] [Bug #12082]'
+
+    tailcall(<<-'end;')
+      def to_be_rescued
+        return do_raise
+        1 + 2
+      rescue
+        errinfo
+      end
+    end;
+    result = to_be_rescued
+    assert_instance_of(RuntimeError, result, bug12082)
+    assert_equal("should be rescued", result.message, bug12082)
+  end
+
   class Bug10557
     def [](_)
       block_given?