Add Thread.ignore_deadlock accessor

Setting this to true disables the deadlock detector.  It should
only be used in cases where the deadlock could be broken via some
external means, such as via a signal.

Now that $SAFE is no longer used, replace the safe_level_ VM flag
with ignore_deadlock for storing the setting.

Fixes [Bug #13768]

1 files changed, 13 insertions, 0 deletions

diff --git a/test/ruby/test_thread.rb b/test/ruby/test_thread.rb
index 30a3cc784e..0af7a37cf8 100644
--- a/test/ruby/test_thread.rb
+++ b/test/ruby/test_thread.rb
@@ -490,6 +490,19 @@ class TestThread < Test::Unit::TestCase
     end;
   end
 
+  def test_ignore_deadlock
+    if /mswin|mingw/ =~ RUBY_PLATFORM
+      skip "can't trap a signal from another process on Windows"
+    end
+    assert_in_out_err([], <<-INPUT, %w(false :sig), [], :signal=>:INT, timeout: 1, timeout_error: nil)
+      p Thread.ignore_deadlock
+      q = Queue.new
+      trap(:INT){q.push :sig}
+      Thread.ignore_deadlock = true
+      p q.pop
+    INPUT
+  end
+
   def test_status_and_stop_p
     a = ::Thread.new {
       Thread.current.report_on_exception = false