Prefer qualified names under Thread

23 files changed, 181 insertions, 179 deletions

diff --git a/benchmark/vm_thread_condvar1.rb b/benchmark/vm_thread_condvar1.rb
index cf5706b23e..feed27c3ad 100644
--- a/benchmark/vm_thread_condvar1.rb
+++ b/benchmark/vm_thread_condvar1.rb
@@ -1,9 +1,9 @@
 # two threads, two mutex, two condvar ping-pong
 require 'thread'
-m1 = Mutex.new
-m2 = Mutex.new
-cv1 = ConditionVariable.new
-cv2 = ConditionVariable.new
+m1 = Thread::Mutex.new
+m2 = Thread::Mutex.new
+cv1 = Thread::ConditionVariable.new
+cv2 = Thread::ConditionVariable.new
 max = 100000
 i = 0
 wait = nil
diff --git a/benchmark/vm_thread_condvar2.rb b/benchmark/vm_thread_condvar2.rb
index 7c8dc19481..6590c4134b 100644
--- a/benchmark/vm_thread_condvar2.rb
+++ b/benchmark/vm_thread_condvar2.rb
@@ -1,16 +1,16 @@
 # many threads, one mutex, many condvars
 require 'thread'
-m = Mutex.new
-cv1 = ConditionVariable.new
-cv2 = ConditionVariable.new
+m = Thread::Mutex.new
+cv1 = Thread::ConditionVariable.new
+cv2 = Thread::ConditionVariable.new
 max = 1000
 n = 100
 waiting = 0
 scvs = []
 waiters = n.times.map do |i|
-  start_cv = ConditionVariable.new
+  start_cv = Thread::ConditionVariable.new
   scvs << start_cv
-  start_mtx = Mutex.new
+  start_mtx = Thread::Mutex.new
   start_mtx.synchronize do
     th = Thread.new(start_mtx, start_cv) do |sm, scv|
       m.synchronize do
diff --git a/bootstraptest/test_insns.rb b/bootstraptest/test_insns.rb
index 9052cad7bd..31fdc29d02 100644
--- a/bootstraptest/test_insns.rb
+++ b/bootstraptest/test_insns.rb
@@ -384,7 +384,7 @@ tests = [
   [ 'opt_empty_p', %q{ ''.empty? }, ],
   [ 'opt_empty_p', %q{ [].empty? }, ],
   [ 'opt_empty_p', %q{ {}.empty? }, ],
-  [ 'opt_empty_p', %q{ Queue.new.empty? }, ],
+  [ 'opt_empty_p', %q{ Thread::Queue.new.empty? }, ],
 
   [ 'opt_succ',  %q{ 1.succ == 2 }, ],
   if defined? $FIXNUM_MAX then
diff --git a/bootstraptest/test_ractor.rb b/bootstraptest/test_ractor.rb
index 80591f6459..28c9e6d90c 100644
--- a/bootstraptest/test_ractor.rb
+++ b/bootstraptest/test_ractor.rb
@@ -533,7 +533,7 @@ assert_equal '[RuntimeError, "ok", true]', %q{
 # threads in a ractor will killed
 assert_equal '{:ok=>3}', %q{
   Ractor.new Ractor.current do |main|
-    q = Queue.new
+    q = Thread::Queue.new
     Thread.new do
       q << true
       loop{}
diff --git a/lib/forwardable.rb b/lib/forwardable.rb
index fb24b8c3e6..c9c4128f9f 100644
--- a/lib/forwardable.rb
+++ b/lib/forwardable.rb
@@ -76,7 +76,7 @@
 #     def_delegators :@q, :clear, :first, :push, :shift, :size
 #   end
 #
-#   q = Queue.new
+#   q = Thread::Queue.new
 #   q.enq 1, 2, 3, 4, 5
 #   q.push 6
 #
diff --git a/lib/mutex_m.rb b/lib/mutex_m.rb
index 18b6256595..706d3c1b3c 100644
--- a/lib/mutex_m.rb
+++ b/lib/mutex_m.rb
@@ -73,32 +73,32 @@ module Mutex_m
     mu_initialize
   end
 
-  # See Mutex#synchronize
+  # See Thread::Mutex#synchronize
   def mu_synchronize(&block)
     @_mutex.synchronize(&block)
   end
 
-  # See Mutex#locked?
+  # See Thread::Mutex#locked?
   def mu_locked?
     @_mutex.locked?
   end
 
-  # See Mutex#try_lock
+  # See Thread::Mutex#try_lock
   def mu_try_lock
     @_mutex.try_lock
   end
 
-  # See Mutex#lock
+  # See Thread::Mutex#lock
   def mu_lock
     @_mutex.lock
   end
 
-  # See Mutex#unlock
+  # See Thread::Mutex#unlock
   def mu_unlock
     @_mutex.unlock
   end
 
-  # See Mutex#sleep
+  # See Thread::Mutex#sleep
   def sleep(timeout = nil)
     @_mutex.sleep(timeout)
   end
diff --git a/sample/drb/dchats.rb b/sample/drb/dchats.rb
index 58af3cf005..c96486a452 100644
--- a/sample/drb/dchats.rb
+++ b/sample/drb/dchats.rb
@@ -28,7 +28,7 @@ end
 
 class ChatServer
   def initialize
-    @mutex = Mutex.new
+    @mutex = Thread::Mutex.new
     @members = {}
   end
 
diff --git a/test/fiber/scheduler.rb b/test/fiber/scheduler.rb
index c844200935..af64e4ebb6 100644
--- a/test/fiber/scheduler.rb
+++ b/test/fiber/scheduler.rb
@@ -21,7 +21,7 @@ class Scheduler
 
     @closed = false
 
-    @lock = Mutex.new
+    @lock = Thread::Mutex.new
     @blocking = 0
     @ready = []
 
@@ -170,7 +170,7 @@ class Scheduler
     Fiber.yield
   end
 
-  # Used for Kernel#sleep and Mutex#sleep
+  # Used for Kernel#sleep and Thread::Mutex#sleep
   def kernel_sleep(duration = nil)
     # $stderr.puts [__method__, duration, Fiber.current].inspect
 
@@ -179,7 +179,8 @@ class Scheduler
     return true
   end
 
-  # Used when blocking on synchronization (Mutex#lock, Queue#pop, SizedQueue#push, ...)
+  # Used when blocking on synchronization (Thread::Mutex#lock,
+  # Thread::Queue#pop, Thread::SizedQueue#push, ...)
   def block(blocker, timeout = nil)
     # $stderr.puts [__method__, blocker, timeout].inspect
 
@@ -201,7 +202,8 @@ class Scheduler
     end
   end
 
-  # Used when synchronization wakes up a previously-blocked fiber (Mutex#unlock, Queue#push, ...).
+  # Used when synchronization wakes up a previously-blocked fiber
+  # (Thread::Mutex#unlock, Thread::Queue#push, ...).
   # This might be called from another thread.
   def unblock(blocker, fiber)
     # $stderr.puts [__method__, blocker, fiber].inspect
diff --git a/test/fiber/test_mutex.rb b/test/fiber/test_mutex.rb
index 0842427760..b0655f06a5 100644
--- a/test/fiber/test_mutex.rb
+++ b/test/fiber/test_mutex.rb
@@ -4,7 +4,7 @@ require_relative 'scheduler'
 
 class TestFiberMutex < Test::Unit::TestCase
   def test_mutex_synchronize
-    mutex = Mutex.new
+    mutex = Thread::Mutex.new
 
     thread = Thread.new do
       scheduler = Scheduler.new
@@ -23,7 +23,7 @@ class TestFiberMutex < Test::Unit::TestCase
   end
 
   def test_mutex_interleaved_locking
-    mutex = Mutex.new
+    mutex = Thread::Mutex.new
 
     thread = Thread.new do
       scheduler = Scheduler.new
@@ -48,7 +48,7 @@ class TestFiberMutex < Test::Unit::TestCase
   end
 
   def test_mutex_thread
-    mutex = Mutex.new
+    mutex = Thread::Mutex.new
     mutex.lock
 
     thread = Thread.new do
@@ -71,7 +71,7 @@ class TestFiberMutex < Test::Unit::TestCase
   end
 
   def test_mutex_fiber_raise
-    mutex = Mutex.new
+    mutex = Thread::Mutex.new
     ran = false
 
     main = Thread.new do
@@ -103,8 +103,8 @@ class TestFiberMutex < Test::Unit::TestCase
   end
 
   def test_condition_variable
-    mutex = Mutex.new
-    condition = ConditionVariable.new
+    mutex = Thread::Mutex.new
+    condition = Thread::ConditionVariable.new
 
     signalled = 0
 
@@ -138,7 +138,7 @@ class TestFiberMutex < Test::Unit::TestCase
   end
 
   def test_queue
-    queue = Queue.new
+    queue = Thread::Queue.new
     processed = 0
 
     thread = Thread.new do
@@ -169,7 +169,7 @@ class TestFiberMutex < Test::Unit::TestCase
   end
 
   def test_queue_pop_waits
-    queue = Queue.new
+    queue = Thread::Queue.new
     running = false
 
     thread = Thread.new do
@@ -198,7 +198,7 @@ class TestFiberMutex < Test::Unit::TestCase
 
     assert_in_out_err %W[-I#{__dir__} -], <<-RUBY, ['in synchronize'], error_pattern, success: false
     require 'scheduler'
-    mutex = Mutex.new
+    mutex = Thread::Mutex.new
 
     thread = Thread.new do
       scheduler = Scheduler.new
diff --git a/test/monitor/test_monitor.rb b/test/monitor/test_monitor.rb
index 0f17d58f71..3eceee7b2e 100644
--- a/test/monitor/test_monitor.rb
+++ b/test/monitor/test_monitor.rb
@@ -19,7 +19,7 @@ class TestMonitor < Test::Unit::TestCase
 
   def test_enter
     ary = []
-    queue = Queue.new
+    queue = Thread::Queue.new
     th = Thread.start {
       queue.pop
       @monitor.enter
@@ -83,7 +83,7 @@ class TestMonitor < Test::Unit::TestCase
 
   def test_synchronize
     ary = []
-    queue = Queue.new
+    queue = Thread::Queue.new
     th = Thread.start {
       queue.pop
       @monitor.synchronize do
@@ -108,7 +108,7 @@ class TestMonitor < Test::Unit::TestCase
 
   def test_killed_thread_in_synchronize
     ary = []
-    queue = Queue.new
+    queue = Thread::Queue.new
     t1 = Thread.start {
       queue.pop
       @monitor.synchronize {
@@ -136,8 +136,8 @@ class TestMonitor < Test::Unit::TestCase
   end
 
   def test_try_enter
-    queue1 = Queue.new
-    queue2 = Queue.new
+    queue1 = Thread::Queue.new
+    queue2 = Thread::Queue.new
     th = Thread.start {
       queue1.deq
       @monitor.enter
@@ -176,8 +176,8 @@ class TestMonitor < Test::Unit::TestCase
   end
 
   def test_mon_locked_and_owned
-    queue1 = Queue.new
-    queue2 = Queue.new
+    queue1 = Thread::Queue.new
+    queue2 = Thread::Queue.new
     th = Thread.start {
       @monitor.enter
       queue1.enq(nil)
@@ -210,7 +210,7 @@ class TestMonitor < Test::Unit::TestCase
     cond = @monitor.new_cond
 
     a = "foo"
-    queue1 = Queue.new
+    queue1 = Thread::Queue.new
     th = Thread.start do
       queue1.deq
       @monitor.synchronize do
@@ -262,7 +262,7 @@ class TestMonitor < Test::Unit::TestCase
   def test_timedwait
     cond = @monitor.new_cond
     b = "foo"
-    queue2 = Queue.new
+    queue2 = Thread::Queue.new
     th = Thread.start do
       queue2.deq
       @monitor.synchronize do
@@ -282,7 +282,7 @@ class TestMonitor < Test::Unit::TestCase
     assert_join_threads([th, th2])
 
     c = "foo"
-    queue3 = Queue.new
+    queue3 = Thread::Queue.new
     th = Thread.start do
       queue3.deq
       @monitor.synchronize do
@@ -312,7 +312,7 @@ class TestMonitor < Test::Unit::TestCase
 #         end
 #       end
 #     }
-#     queue3 = Queue.new
+#     queue3 = Thread::Queue.new
 #     Thread.start do
 #       queue3.pop
 #       @monitor.synchronize do
diff --git a/test/ruby/test_bignum.rb b/test/ruby/test_bignum.rb
index 68c8461951..3ffe7114b5 100644
--- a/test/ruby/test_bignum.rb
+++ b/test/ruby/test_bignum.rb
@@ -632,7 +632,7 @@ class TestBignum < Test::Unit::TestCase
     time = Time.now
     end_flag = false
     num = (65536 ** 65536)
-    q = Queue.new
+    q = Thread::Queue.new
     thread = Thread.new do
       assert_raise(RuntimeError) {
         q << true
diff --git a/test/ruby/test_dir.rb b/test/ruby/test_dir.rb
index bb268f2ab3..71bff5f5c3 100644
--- a/test/ruby/test_dir.rb
+++ b/test/ruby/test_dir.rb
@@ -131,7 +131,7 @@ class TestDir < Test::Unit::TestCase
 
   def test_chdir_conflict
     pwd = Dir.pwd
-    q = Queue.new
+    q = Thread::Queue.new
     t = Thread.new do
       q.pop
       Dir.chdir(pwd) rescue $!
diff --git a/test/ruby/test_exception.rb b/test/ruby/test_exception.rb
index 8c4e6889ab..62da13d1b9 100644
--- a/test/ruby/test_exception.rb
+++ b/test/ruby/test_exception.rb
@@ -814,7 +814,7 @@ end.join
     bug12741 = '[ruby-core:77222] [Bug #12741]'
 
     x = Thread.current
-    q = Queue.new
+    q = Thread::Queue.new
     y = Thread.start do
       q.pop
       begin
diff --git a/test/ruby/test_io.rb b/test/ruby/test_io.rb
index 7acedb60e2..f7240c4cf6 100644
--- a/test/ruby/test_io.rb
+++ b/test/ruby/test_io.rb
@@ -3736,7 +3736,7 @@ __END__
     begin;
       bug13158 = '[ruby-core:79262] [Bug #13158]'
       closed = nil
-      q = Queue.new
+      q = Thread::Queue.new
       IO.pipe do |r, w|
         thread = Thread.new do
           begin
diff --git a/test/ruby/test_process.rb b/test/ruby/test_process.rb
index 0493544139..80d2eefca9 100644
--- a/test/ruby/test_process.rb
+++ b/test/ruby/test_process.rb
@@ -2433,7 +2433,7 @@ EOS
         rescue SystemCallError
           w.syswrite("exec failed\n")
         end
-        q = Queue.new
+        q = Thread::Queue.new
         th1 = Thread.new { i = 0; i += 1 while q.empty?; i }
         th2 = Thread.new { j = 0; j += 1 while q.empty? && Thread.pass.nil?; j }
         sleep 0.5
diff --git a/test/ruby/test_settracefunc.rb b/test/ruby/test_settracefunc.rb
index c8ec81c72a..dafe58d70c 100644
--- a/test/ruby/test_settracefunc.rb
+++ b/test/ruby/test_settracefunc.rb
@@ -1984,7 +1984,7 @@ class TestSetTraceFunc < Test::Unit::TestCase
   def test_thread_add_trace_func
     events = []
     base_line = __LINE__
-    q = Queue.new
+    q = Thread::Queue.new
     t = Thread.new{
       Thread.current.add_trace_func proc{|ev, file, line, *args|
         events << [ev, line]
@@ -2010,7 +2010,7 @@ class TestSetTraceFunc < Test::Unit::TestCase
 
     # other thread
     events = []
-    m2t_q = Queue.new
+    m2t_q = Thread::Queue.new
 
     t = Thread.new{
       Thread.current.abort_on_exception = true
@@ -2320,8 +2320,8 @@ class TestSetTraceFunc < Test::Unit::TestCase
       events << Thread.current
     end
 
-    q1 = Queue.new
-    q2 = Queue.new
+    q1 = Thread::Queue.new
+    q2 = Thread::Queue.new
 
     th = Thread.new{
       q1 << :ok; q2.pop
diff --git a/test/ruby/test_thread.rb b/test/ruby/test_thread.rb
index dbd0328e28..a75d42b962 100644
--- a/test/ruby/test_thread.rb
+++ b/test/ruby/test_thread.rb
@@ -496,7 +496,7 @@ class TestThread < Test::Unit::TestCase
     end
     assert_in_out_err([], <<-INPUT, %w(false :sig), [], :signal=>:INT, timeout: 1, timeout_error: nil)
       p Thread.ignore_deadlock
-      q = Queue.new
+      q = Thread::Queue.new
       trap(:INT){q.push :sig}
       Thread.ignore_deadlock = true
       p q.pop
@@ -731,8 +731,8 @@ class TestThread < Test::Unit::TestCase
 
   def make_handle_interrupt_test_thread1 flag
     r = []
-    ready_q = Queue.new
-    done_q = Queue.new
+    ready_q = Thread::Queue.new
+    done_q = Thread::Queue.new
     th = Thread.new{
       begin
         Thread.handle_interrupt(RuntimeError => flag){
@@ -809,7 +809,7 @@ class TestThread < Test::Unit::TestCase
 
   def test_handle_interrupt_blocking
     r = nil
-    q = Queue.new
+    q = Thread::Queue.new
     e = Class.new(Exception)
     th_s = Thread.current
     th = Thread.start {
@@ -833,7 +833,7 @@ class TestThread < Test::Unit::TestCase
   def test_handle_interrupt_and_io
     assert_in_out_err([], <<-INPUT, %w(ok), [])
       th_waiting = true
-      q = Queue.new
+      q = Thread::Queue.new
 
       t = Thread.new {
         Thread.current.report_on_exception = false
@@ -1235,7 +1235,7 @@ q.pop
   end if Process.respond_to?(:fork)
 
   def test_fork_while_locked
-    m = Mutex.new
+    m = Thread::Mutex.new
     thrs = []
     3.times do |i|
       thrs << Thread.new { m.synchronize { Process.waitpid2(fork{})[1] } }
@@ -1268,7 +1268,7 @@ q.pop
 
   def test_fork_while_mutex_locked_by_forker
     skip 'needs fork' unless Process.respond_to?(:fork)
-    m = Mutex.new
+    m = Thread::Mutex.new
     m.synchronize do
       pid = fork do
         exit!(2) unless m.locked?
diff --git a/test/ruby/test_thread_cv.rb b/test/ruby/test_thread_cv.rb
index 38bcc3b8fa..5f19b85bc0 100644
--- a/test/ruby/test_thread_cv.rb
+++ b/test/ruby/test_thread_cv.rb
@@ -13,8 +13,8 @@ class TestThreadConditionVariable < Test::Unit::TestCase
   end
 
   def test_condvar_signal_and_wait
-    mutex = Mutex.new
-    condvar = ConditionVariable.new
+    mutex = Thread::Mutex.new
+    condvar = Thread::ConditionVariable.new
     result = []
     mutex.synchronize do
       t = Thread.new do
@@ -35,8 +35,8 @@ class TestThreadConditionVariable < Test::Unit::TestCase
   def test_condvar_wait_exception_handling
     # Calling wait in the only thread running should raise a ThreadError of
     # 'stopping only thread'
-    mutex = Mutex.new
-    condvar = ConditionVariable.new
+    mutex = Thread::Mutex.new
+    condvar = Thread::ConditionVariable.new
 
     locked = false
     thread = Thread.new do
@@ -61,8 +61,8 @@ class TestThreadConditionVariable < Test::Unit::TestCase
   def test_condvar_wait_and_broadcast
     nr_threads = 3
     threads = Array.new
-    mutex = Mutex.new
-    condvar = ConditionVariable.new
+    mutex = Thread::Mutex.new
+    condvar = Thread::ConditionVariable.new
     result = []
 
     nr_threads.times do |i|
@@ -91,8 +91,8 @@ class TestThreadConditionVariable < Test::Unit::TestCase
 
   def test_condvar_wait_deadlock
     assert_in_out_err([], <<-INPUT, /\Afatal\nNo live threads left\. Deadlock/, [])
-      mutex = Mutex.new
-      cv = ConditionVariable.new
+      mutex = Thread::Mutex.new
+      cv = Thread::ConditionVariable.new
 
       klass = nil
       mesg = nil
@@ -112,8 +112,8 @@ INPUT
   def test_condvar_wait_deadlock_2
     nr_threads = 3
     threads = Array.new
-    mutex = Mutex.new
-    condvar = ConditionVariable.new
+    mutex = Thread::Mutex.new
+    condvar = Thread::ConditionVariable.new
 
     nr_threads.times do |i|
       if (i != 0)
@@ -136,8 +136,8 @@ INPUT
   end
 
   def test_condvar_timed_wait
-    mutex = Mutex.new
-    condvar = ConditionVariable.new
+    mutex = Thread::Mutex.new
+    condvar = Thread::ConditionVariable.new
     timeout = 0.3
     locked = false
 
@@ -157,15 +157,15 @@ INPUT
   end
 
   def test_condvar_nolock
-    mutex = Mutex.new
-    condvar = ConditionVariable.new
+    mutex = Thread::Mutex.new
+    condvar = Thread::ConditionVariable.new
 
     assert_raise(ThreadError) {condvar.wait(mutex)}
   end
 
   def test_condvar_nolock_2
-    mutex = Mutex.new
-    condvar = ConditionVariable.new
+    mutex = Thread::Mutex.new
+    condvar = Thread::ConditionVariable.new
 
     Thread.new do
       assert_raise(ThreadError) {condvar.wait(mutex)}
@@ -173,8 +173,8 @@ INPUT
   end
 
   def test_condvar_nolock_3
-    mutex = Mutex.new
-    condvar = ConditionVariable.new
+    mutex = Thread::Mutex.new
+    condvar = Thread::ConditionVariable.new
 
     Thread.new do
       assert_raise(ThreadError) {condvar.wait(mutex, 0.1)}
@@ -182,22 +182,22 @@ INPUT
   end
 
   def test_condvar_empty_signal
-    mutex = Mutex.new
-    condvar = ConditionVariable.new
+    mutex = Thread::Mutex.new
+    condvar = Thread::ConditionVariable.new
 
     assert_nothing_raised(Exception) { mutex.synchronize {condvar.signal} }
   end
 
   def test_condvar_empty_broadcast
-    mutex = Mutex.new
-    condvar = ConditionVariable.new
+    mutex = Thread::Mutex.new
+    condvar = Thread::ConditionVariable.new
 
     assert_nothing_raised(Exception) { mutex.synchronize {condvar.broadcast} }
   end
 
   def test_dup
     bug9440 = '[ruby-core:59961] [Bug #9440]'
-    condvar = ConditionVariable.new
+    condvar = Thread::ConditionVariable.new
     assert_raise(NoMethodError, bug9440) do
       condvar.dup
     end
@@ -207,7 +207,7 @@ INPUT
 
   def test_dump
     bug9674 = '[ruby-core:61677] [Bug #9674]'
-    condvar = ConditionVariable.new
+    condvar = Thread::ConditionVariable.new
     assert_raise_with_message(TypeError, /#{ConditionVariable}/, bug9674) do
       Marshal.dump(condvar)
     end
@@ -219,8 +219,8 @@ INPUT
   end
 
   def test_condvar_fork
-    mutex = Mutex.new
-    condvar = ConditionVariable.new
+    mutex = Thread::Mutex.new
+    condvar = Thread::ConditionVariable.new
     thrs = (1..10).map do
       Thread.new { mutex.synchronize { condvar.wait(mutex) } }
     end
diff --git a/test/ruby/test_thread_queue.rb b/test/ruby/test_thread_queue.rb
index 6185abff9f..3fa0eae2c1 100644
--- a/test/ruby/test_thread_queue.rb
+++ b/test/ruby/test_thread_queue.rb
@@ -66,7 +66,7 @@ class TestThreadQueue < Test::Unit::TestCase
                            [e, "Enumerable"],
                            [Struct.new(:to_a), "Array-like"],
                            ) do |a, type|
-      q = Queue.new(a.new([1,2,3]))
+      q = Thread::Queue.new(a.new([1,2,3]))
       assert_equal(3, q.size, type)
       assert_not_predicate(q, :empty?, type)
       assert_equal(1, q.pop, type)
@@ -77,14 +77,14 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_sized_queue_initialize
-    q = SizedQueue.new(1)
+    q = Thread::SizedQueue.new(1)
     assert_equal 1, q.max
-    assert_raise(ArgumentError) { SizedQueue.new(0) }
-    assert_raise(ArgumentError) { SizedQueue.new(-1) }
+    assert_raise(ArgumentError) { Thread::SizedQueue.new(0) }
+    assert_raise(ArgumentError) { Thread::SizedQueue.new(-1) }
   end
 
   def test_sized_queue_assign_max
-    q = SizedQueue.new(2)
+    q = Thread::SizedQueue.new(2)
     assert_equal(2, q.max)
     q.max = 1
     assert_equal(1, q.max)
@@ -104,7 +104,7 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_queue_pop_interrupt
-    q = Queue.new
+    q = Thread::Queue.new
     t1 = Thread.new { q.pop }
     sleep 0.01 until t1.stop?
     t1.kill.join
@@ -112,14 +112,14 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_queue_pop_non_block
-    q = Queue.new
+    q = Thread::Queue.new
     assert_raise_with_message(ThreadError, /empty/) do
       q.pop(true)
     end
   end
 
   def test_sized_queue_pop_interrupt
-    q = SizedQueue.new(1)
+    q = Thread::SizedQueue.new(1)
     t1 = Thread.new { q.pop }
     sleep 0.01 until t1.stop?
     t1.kill.join
@@ -127,14 +127,14 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_sized_queue_pop_non_block
-    q = SizedQueue.new(1)
+    q = Thread::SizedQueue.new(1)
     assert_raise_with_message(ThreadError, /empty/) do
       q.pop(true)
     end
   end
 
   def test_sized_queue_push_interrupt
-    q = SizedQueue.new(1)
+    q = Thread::SizedQueue.new(1)
     q.push(1)
     assert_raise_with_message(ThreadError, /full/) do
       q.push(2, true)
@@ -142,7 +142,7 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_sized_queue_push_non_block
-    q = SizedQueue.new(1)
+    q = Thread::SizedQueue.new(1)
     q.push(1)
     t1 = Thread.new { q.push(2) }
     sleep 0.01 until t1.stop?
@@ -159,7 +159,7 @@ class TestThreadQueue < Test::Unit::TestCase
         assert_normal_exit(<<-"_eom", bug5343, **{:timeout => timeout, :chdir=>d})
           #{total_count}.times do |i|
             open("test_thr_kill_count", "w") {|f| f.puts i }
-            queue = Queue.new
+            queue = Thread::Queue.new
             r, w = IO.pipe
             th = Thread.start {
               queue.push(nil)
@@ -178,20 +178,20 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_queue_push_return_value
-    q = Queue.new
+    q = Thread::Queue.new
     retval = q.push(1)
     assert_same q, retval
   end
 
   def test_queue_clear_return_value
-    q = Queue.new
+    q = Thread::Queue.new
     retval = q.clear
     assert_same q, retval
   end
 
   def test_sized_queue_clear
-    # Fill queue, then test that SizedQueue#clear wakes up all waiting threads
-    sq = SizedQueue.new(2)
+    # Fill queue, then test that Thread::SizedQueue#clear wakes up all waiting threads
+    sq = Thread::SizedQueue.new(2)
     2.times { sq << 1 }
 
     t1 = Thread.new do
@@ -212,19 +212,19 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_sized_queue_push_return_value
-    q = SizedQueue.new(1)
+    q = Thread::SizedQueue.new(1)
     retval = q.push(1)
     assert_same q, retval
   end
 
   def test_sized_queue_clear_return_value
-    q = SizedQueue.new(1)
+    q = Thread::SizedQueue.new(1)
     retval = q.clear
     assert_same q, retval
   end
 
   def test_sized_queue_throttle
-    q = SizedQueue.new(1)
+    q = Thread::SizedQueue.new(1)
     i = 0
     consumer = Thread.new do
       while q.pop
@@ -247,7 +247,7 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_queue_thread_raise
-    q = Queue.new
+    q = Thread::Queue.new
     th1 = Thread.new do
       begin
         q.pop
@@ -277,7 +277,7 @@ class TestThreadQueue < Test::Unit::TestCase
 
   def test_dup
     bug9440 = '[ruby-core:59961] [Bug #9440]'
-    q = Queue.new
+    q = Thread::Queue.new
     assert_raise(NoMethodError, bug9440) do
       q.dup
     end
@@ -287,12 +287,12 @@ class TestThreadQueue < Test::Unit::TestCase
 
   def test_dump
     bug9674 = '[ruby-core:61677] [Bug #9674]'
-    q = Queue.new
+    q = Thread::Queue.new
     assert_raise_with_message(TypeError, /#{Queue}/, bug9674) do
       Marshal.dump(q)
     end
 
-    sq = SizedQueue.new(1)
+    sq = Thread::SizedQueue.new(1)
     assert_raise_with_message(TypeError, /#{SizedQueue}/, bug9674) do
       Marshal.dump(sq)
     end
@@ -304,7 +304,7 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_close
-    [->{Queue.new}, ->{SizedQueue.new 3}].each do |qcreate|
+    [->{Thread::Queue.new}, ->{Thread::SizedQueue.new 3}].each do |qcreate|
       q = qcreate.call
       assert_equal false, q.closed?
       q << :something
@@ -343,15 +343,15 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_queue_close_wakeup
-    close_wakeup(15, 18){Queue.new}
+    close_wakeup(15, 18){Thread::Queue.new}
   end
 
   def test_size_queue_close_wakeup
-    close_wakeup(5, 8){SizedQueue.new 9}
+    close_wakeup(5, 8){Thread::SizedQueue.new 9}
   end
 
   def test_sized_queue_one_closed_interrupt
-    q = SizedQueue.new 1
+    q = Thread::SizedQueue.new 1
     q << :one
     t1 = Thread.new {
       Thread.current.report_on_exception = false
@@ -368,7 +368,7 @@ class TestThreadQueue < Test::Unit::TestCase
 
   # make sure that shutdown state is handled properly by empty? for the non-blocking case
   def test_empty_non_blocking
-    q = SizedQueue.new 3
+    q = Thread::SizedQueue.new 3
     3.times{|i| q << i}
 
     # these all block cos the queue is full
@@ -394,13 +394,13 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_sized_queue_closed_push_non_blocking
-    q = SizedQueue.new 7
+    q = Thread::SizedQueue.new 7
     q.close
     assert_raise_with_message(ClosedQueueError, /queue closed/){q.push(non_block=true)}
   end
 
   def test_blocked_pushers
-    q = SizedQueue.new 3
+    q = Thread::SizedQueue.new 3
     prod_threads = 6.times.map do |i|
       thr = Thread.new{
         Thread.current.report_on_exception = false
@@ -446,9 +446,9 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_deny_pushers
-    [->{Queue.new}, ->{SizedQueue.new 3}].each do |qcreate|
+    [->{Thread::Queue.new}, ->{Thread::SizedQueue.new 3}].each do |qcreate|
       q = qcreate[]
-      synq = Queue.new
+      synq = Thread::Queue.new
       prod_threads = 20.times.map do |i|
         Thread.new {
           synq.pop
@@ -466,7 +466,7 @@ class TestThreadQueue < Test::Unit::TestCase
 
   # size should account for waiting pushers during shutdown
   def sized_queue_size_close
-    q = SizedQueue.new 4
+    q = Thread::SizedQueue.new 4
     4.times{|i| q << i}
     Thread.new{ q << 5 }
     Thread.new{ q << 6 }
@@ -478,7 +478,7 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_blocked_pushers_empty
-    q = SizedQueue.new 3
+    q = Thread::SizedQueue.new 3
     prod_threads = 6.times.map do |i|
       Thread.new{
         Thread.current.report_on_exception = false
@@ -510,14 +510,14 @@ class TestThreadQueue < Test::Unit::TestCase
 
   # test thread wakeup on one-element SizedQueue with close
   def test_one_element_sized_queue
-    q = SizedQueue.new 1
+    q = Thread::SizedQueue.new 1
     t = Thread.new{ q.pop }
     q.close
     assert_nil t.value
   end
 
   def test_close_twice
-    [->{Queue.new}, ->{SizedQueue.new 3}].each do |qcreate|
+    [->{Thread::Queue.new}, ->{Thread::SizedQueue.new 3}].each do |qcreate|
       q = qcreate[]
       q.close
       assert_nothing_raised(ClosedQueueError){q.close}
@@ -525,7 +525,7 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_queue_close_multi_multi
-    q = SizedQueue.new rand(800..1200)
+    q = Thread::SizedQueue.new rand(800..1200)
 
     count_items = rand(3000..5000)
     count_producers = rand(10..20)
@@ -587,7 +587,7 @@ class TestThreadQueue < Test::Unit::TestCase
     end
 
     assert_in_out_err([], <<-INPUT, %w(INT INT exit), [])
-      q = Queue.new
+      q = Thread::Queue.new
       trap(:INT){
         q.push 'INT'
       }
@@ -604,8 +604,8 @@ class TestThreadQueue < Test::Unit::TestCase
   end
 
   def test_fork_while_queue_waiting
-    q = Queue.new
-    sq = SizedQueue.new(1)
+    q = Thread::Queue.new
+    sq = Thread::SizedQueue.new(1)
     thq = Thread.new { q.pop }
     thsq = Thread.new { sq.pop }
     Thread.pass until thq.stop? && thsq.stop?
diff --git a/test/test_pstore.rb b/test/test_pstore.rb
index 52b74f3775..fe5f8711a4 100644
--- a/test/test_pstore.rb
+++ b/test/test_pstore.rb
@@ -75,7 +75,7 @@ class PStoreTest < Test::Unit::TestCase
   end
 
   def test_thread_safe
-    q1 = Queue.new
+    q1 = Thread::Queue.new
     assert_raise(PStore::Error) do
       th = Thread.new do
         @pstore.transaction do
@@ -92,7 +92,7 @@ class PStoreTest < Test::Unit::TestCase
         th.join
       end
     end
-    q2 = Queue.new
+    q2 = Thread::Queue.new
     begin
       pstore = PStore.new(second_file, true)
       cur = Thread.current
diff --git a/test/yaml/test_store.rb b/test/yaml/test_store.rb
index 9112c569a3..ef8d3229c1 100644
--- a/test/yaml/test_store.rb
+++ b/test/yaml/test_store.rb
@@ -75,7 +75,7 @@ class YAMLStoreTest < Test::Unit::TestCase
   end
 
   def test_thread_safe
-    q1 = Queue.new
+    q1 = Thread::Queue.new
     assert_raise(PStore::Error) do
       th = Thread.new do
         @yaml_store.transaction do
@@ -92,7 +92,7 @@ class YAMLStoreTest < Test::Unit::TestCase
         th.join
       end
     end
-    q2 = Queue.new
+    q2 = Thread::Queue.new
     begin
       yaml_store = YAML::Store.new(second_file, true)
       cur = Thread.current
diff --git a/thread.c b/thread.c
index 2d3a3e15c2..f7372d3dd2 100644
--- a/thread.c
+++ b/thread.c
@@ -3153,7 +3153,7 @@ rb_thread_s_ignore_deadlock(VALUE _)
  *  deadlock condition via some other means, such as a signal.
  *
  *     Thread.ignore_deadlock = true
- *     queue = Queue.new
+ *     queue = Thread::Queue.new
  *
  *     trap(:SIGUSR1){queue.push "Received signal"}
  *
diff --git a/thread_sync.c b/thread_sync.c
index f78b0b5357..2837f454f4 100644
--- a/thread_sync.c
+++ b/thread_sync.c
@@ -65,14 +65,14 @@ static void rb_mutex_abandon_locking_mutex(rb_thread_t *th);
 static const char* rb_mutex_unlock_th(rb_mutex_t *mutex, rb_thread_t *th, rb_fiber_t *fiber);
 
 /*
- *  Document-class: Mutex
+ *  Document-class: Thread::Mutex
  *
- *  Mutex implements a simple semaphore that can be used to coordinate access to
- *  shared data from multiple concurrent threads.
+ *  Thread::Mutex implements a simple semaphore that can be used to
+ *  coordinate access to shared data from multiple concurrent threads.
  *
  *  Example:
  *
- *    semaphore = Mutex.new
+ *    semaphore = Thread::Mutex.new
  *
  *    a = Thread.new {
  *      semaphore.synchronize {
@@ -164,7 +164,7 @@ mutex_alloc(VALUE klass)
 
 /*
  *  call-seq:
- *     Mutex.new   -> mutex
+ *     Thread::Mutex.new   -> mutex
  *
  *  Creates a new Mutex
  */
@@ -600,7 +600,7 @@ mutex_sleep(int argc, VALUE *argv, VALUE self)
  *    mutex.synchronize { ... }    -> result of the block
  *
  * Obtains a lock, runs the block, and releases the lock when the block
- * completes.  See the example under +Mutex+.
+ * completes.  See the example under Thread::Mutex.
  */
 
 VALUE
@@ -615,7 +615,7 @@ rb_mutex_synchronize(VALUE mutex, VALUE (*func)(VALUE arg), VALUE arg)
  *    mutex.synchronize { ... }    -> result of the block
  *
  * Obtains a lock, runs the block, and releases the lock when the block
- * completes.  See the example under +Mutex+.
+ * completes.  See the example under Thread::Mutex.
  */
 static VALUE
 rb_mutex_synchronize_m(VALUE self)
@@ -792,7 +792,7 @@ queue_closed_p(VALUE self)
  *  Document-class: ClosedQueueError
  *
  *  The exception class which will be raised when pushing into a closed
- *  Queue.  See Queue#close and SizedQueue#close.
+ *  Queue.  See Thread::Queue#close and Thread::SizedQueue#close.
  */
 
 NORETURN(static void raise_closed_queue_error(VALUE self));
@@ -811,19 +811,19 @@ queue_closed_result(VALUE self, struct rb_queue *q)
 }
 
 /*
- *  Document-class: Queue
+ *  Document-class: Thread::Queue
  *
- *  The Queue class implements multi-producer, multi-consumer queues.
- *  It is especially useful in threaded programming when information
- *  must be exchanged safely between multiple threads. The Queue class
- *  implements all the required locking semantics.
+ *  The Thread::Queue class implements multi-producer, multi-consumer
+ *  queues.  It is especially useful in threaded programming when
+ *  information must be exchanged safely between multiple threads. The
+ *  Thread::Queue class implements all the required locking semantics.
  *
  *  The class implements FIFO type of queue. In a FIFO queue, the first
  *  tasks added are the first retrieved.
  *
  *  Example:
  *
- *	queue = Queue.new
+ *	queue = Thread::Queue.new
  *
  *	producer = Thread.new do
  *	  5.times do |i|
@@ -853,9 +853,9 @@ queue_closed_result(VALUE self, struct rb_queue *q)
  *
  *  Example:
  *
- *    	q = Queue.new
- *    	q = Queue.new([a, b, c])
- *    	q = Queue.new(items)
+ *    	q = Thread::Queue.new
+ *    	q = Thread::Queue.new([a, b, c])
+ *    	q = Thread::Queue.new(items)
  */
 
 static VALUE
@@ -886,7 +886,7 @@ queue_do_push(VALUE self, struct rb_queue *q, VALUE obj)
 }
 
 /*
- * Document-method: Queue#close
+ * Document-method: Thread::Queue#close
  * call-seq:
  *   close
  *
@@ -909,7 +909,7 @@ queue_do_push(VALUE self, struct rb_queue *q, VALUE obj)
  *
  * Example:
  *
- *    	q = Queue.new
+ *    	q = Thread::Queue.new
  *      Thread.new{
  *        while e = q.deq # wait for nil to break loop
  *          # ...
@@ -933,7 +933,7 @@ rb_queue_close(VALUE self)
 }
 
 /*
- * Document-method: Queue#closed?
+ * Document-method: Thread::Queue#closed?
  * call-seq: closed?
  *
  * Returns +true+ if the queue is closed.
@@ -946,7 +946,7 @@ rb_queue_closed_p(VALUE self)
 }
 
 /*
- * Document-method: Queue#push
+ * Document-method: Thread::Queue#push
  * call-seq:
  *   push(object)
  *   enq(object)
@@ -1049,7 +1049,7 @@ queue_pop_should_block(int argc, const VALUE *argv)
 }
 
 /*
- * Document-method: Queue#pop
+ * Document-method: Thread::Queue#pop
  * call-seq:
  *   pop(non_block=false)
  *   deq(non_block=false)
@@ -1070,7 +1070,7 @@ rb_queue_pop(int argc, VALUE *argv, VALUE self)
 }
 
 /*
- * Document-method: Queue#empty?
+ * Document-method: Thread::Queue#empty?
  * call-seq: empty?
  *
  * Returns +true+ if the queue is empty.
@@ -1083,7 +1083,7 @@ rb_queue_empty_p(VALUE self)
 }
 
 /*
- * Document-method: Queue#clear
+ * Document-method: Thread::Queue#clear
  *
  * Removes all objects from the queue.
  */
@@ -1098,7 +1098,7 @@ rb_queue_clear(VALUE self)
 }
 
 /*
- * Document-method: Queue#length
+ * Document-method: Thread::Queue#length
  * call-seq:
  *   length
  *   size
@@ -1113,7 +1113,7 @@ rb_queue_length(VALUE self)
 }
 
 /*
- * Document-method: Queue#num_waiting
+ * Document-method: Thread::Queue#num_waiting
  *
  * Returns the number of threads waiting on the queue.
  */
@@ -1127,12 +1127,12 @@ rb_queue_num_waiting(VALUE self)
 }
 
 /*
- *  Document-class: SizedQueue
+ *  Document-class: Thread::SizedQueue
  *
  * This class represents queues of specified size capacity.  The push operation
  * may be blocked if the capacity is full.
  *
- * See Queue for an example of how a SizedQueue works.
+ * See Thread::Queue for an example of how a Thread::SizedQueue works.
  */
 
 /*
@@ -1162,11 +1162,11 @@ rb_szqueue_initialize(VALUE self, VALUE vmax)
 }
 
 /*
- * Document-method: SizedQueue#close
+ * Document-method: Thread::SizedQueue#close
  * call-seq:
  *   close
  *
- * Similar to Queue#close.
+ * Similar to Thread::Queue#close.
  *
  * The difference is behavior with waiting enqueuing threads.
  *
@@ -1187,7 +1187,7 @@ rb_szqueue_close(VALUE self)
 }
 
 /*
- * Document-method: SizedQueue#max
+ * Document-method: Thread::SizedQueue#max
  *
  * Returns the maximum size of the queue.
  */
@@ -1199,7 +1199,7 @@ rb_szqueue_max_get(VALUE self)
 }
 
 /*
- * Document-method: SizedQueue#max=
+ * Document-method: Thread::SizedQueue#max=
  * call-seq: max=(number)
  *
  * Sets the maximum size of the queue to the given +number+.
@@ -1235,7 +1235,7 @@ szqueue_push_should_block(int argc, const VALUE *argv)
 }
 
 /*
- * Document-method: SizedQueue#push
+ * Document-method: Thread::SizedQueue#push
  * call-seq:
  *   push(object, non_block=false)
  *   enq(object, non_block=false)
@@ -1299,7 +1299,7 @@ szqueue_do_pop(VALUE self, int should_block)
 }
 
 /*
- * Document-method: SizedQueue#pop
+ * Document-method: Thread::SizedQueue#pop
  * call-seq:
  *   pop(non_block=false)
  *   deq(non_block=false)
@@ -1320,7 +1320,7 @@ rb_szqueue_pop(int argc, VALUE *argv, VALUE self)
 }
 
 /*
- * Document-method: SizedQueue#clear
+ * Document-method: Thread::SizedQueue#clear
  *
  * Removes all objects from the queue.
  */
@@ -1336,7 +1336,7 @@ rb_szqueue_clear(VALUE self)
 }
 
 /*
- * Document-method: SizedQueue#length
+ * Document-method: Thread::SizedQueue#length
  * call-seq:
  *   length
  *   size
@@ -1353,7 +1353,7 @@ rb_szqueue_length(VALUE self)
 }
 
 /*
- * Document-method: SizedQueue#num_waiting
+ * Document-method: Thread::SizedQueue#num_waiting
  *
  * Returns the number of threads waiting on the queue.
  */
@@ -1367,7 +1367,7 @@ rb_szqueue_num_waiting(VALUE self)
 }
 
 /*
- * Document-method: SizedQueue#empty?
+ * Document-method: Thread::SizedQueue#empty?
  * call-seq: empty?
  *
  * Returns +true+ if the queue is empty.
@@ -1389,7 +1389,7 @@ struct rb_condvar {
 };
 
 /*
- *  Document-class: ConditionVariable
+ *  Document-class: Thread::ConditionVariable
  *
  *  ConditionVariable objects augment class Mutex. Using condition variables,
  *  it is possible to suspend while in the middle of a critical section until a
@@ -1397,8 +1397,8 @@ struct rb_condvar {
  *
  *  Example:
  *
- *    mutex = Mutex.new
- *    resource = ConditionVariable.new
+ *    mutex = Thread::Mutex.new
+ *    resource = Thread::ConditionVariable.new
  *
  *    a = Thread.new {
  *	 mutex.synchronize {
@@ -1486,7 +1486,7 @@ do_sleep(VALUE args)
 }
 
 /*
- * Document-method: ConditionVariable#wait
+ * Document-method: Thread::ConditionVariable#wait
  * call-seq: wait(mutex, timeout=nil)
  *
  * Releases the lock held in +mutex+ and waits; reacquires the lock on wakeup.
@@ -1517,7 +1517,7 @@ rb_condvar_wait(int argc, VALUE *argv, VALUE self)
 }
 
 /*
- * Document-method: ConditionVariable#signal
+ * Document-method: Thread::ConditionVariable#signal
  *
  * Wakes up the first thread in line waiting for this lock.
  */
@@ -1531,7 +1531,7 @@ rb_condvar_signal(VALUE self)
 }
 
 /*
- * Document-method: ConditionVariable#broadcast
+ * Document-method: Thread::ConditionVariable#broadcast
  *
  * Wakes up all threads waiting for this lock.
  */
@@ -1565,11 +1565,11 @@ static void
 Init_thread_sync(void)
 {
 #undef rb_intern
-#if 0
-    rb_cMutex = rb_define_class("Mutex", rb_cObject); /* teach rdoc Mutex */
-    rb_cConditionVariable = rb_define_class("ConditionVariable", rb_cObject); /* teach rdoc ConditionVariable */
-    rb_cQueue = rb_define_class("Queue", rb_cObject); /* teach rdoc Queue */
-    rb_cSizedQueue = rb_define_class("SizedQueue", rb_cObject); /* teach rdoc SizedQueue */
+#if defined(TEACH_RDOC) && TEACH_RDOC == 42
+    rb_cMutex = rb_define_class_under(rb_cThread, "Mutex", rb_cObject);
+    rb_cConditionVariable = rb_define_class_under(rb_cThread, "ConditionVariable", rb_cObject);
+    rb_cQueue = rb_define_class_under(rb_cThread, "Queue", rb_cObject);
+    rb_cSizedQueue = rb_define_class_under(rb_cThread, "SizedQueue", rb_cObject);
 #endif
 
 #define DEFINE_CLASS(name, super) \