merge revision(s) 55605: [Backport #12565]

	* vm_args.c (vm_caller_setup_arg_block): disable symbol block
	  argument optimization when tail call optimization is enabled,
	  in order to avoid SEGV.  [ruby-core:76288] [Bug #12565]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_3@55779 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 15 insertions, 0 deletions

diff --git a/test/ruby/test_optimization.rb b/test/ruby/test_optimization.rb
index 15fb9195c9..f147f9d8c6 100644
--- a/test/ruby/test_optimization.rb
+++ b/test/ruby/test_optimization.rb
@@ -319,6 +319,21 @@ class TestRubyOptimization < Test::Unit::TestCase
     assert_equal("should be rescued", result.message, bug12082)
   end
 
+  def test_tailcall_symbol_block_arg
+    bug12565 = '[ruby-core:46065]'
+    tailcall(<<-EOF)
+      def apply_one_and_two(&block)
+        yield(1, 2)
+      end
+
+      def add_one_and_two
+        apply_one_and_two(&:+)
+      end
+    EOF
+    assert_equal(3, add_one_and_two,
+                 message(bug12565) {disasm(:add_one_and_two)})
+  end
+
   class Bug10557
     def [](_)
       block_given?