Disable test on 1.8.7, since workaround is to allow blocking on that version

spec/process_shared/semaphore_spec.rb

@@ -158,35 +158,37 @@ module ProcessShared
         end
       end
 
-      it 'allows other threads in a process to continue while waiting' do
-        start = Time.now.to_f
-        sem = Semaphore.new
-        was_set = false
-        t2 = nil
+      unless RUBY_VERSION == '1.8.7'
+        it 'allows other threads in a process to continue while waiting' do
+          start = Time.now.to_f
+          sem = Semaphore.new
+          was_set = false
+          t2 = nil
 
-        sem.synchronize do
-          t1 = Thread.new do
-            # give t2 a chance to wait on the lock, then set the flag
-            sleep 0.01
-            was_set = true
-          end
-
-          t2 = Thread.new do
-            begin
-              sem.try_wait(10.0)
-            rescue Errno::ETIMEDOUT
-              # success
+          sem.synchronize do
+            t1 = Thread.new do
+              # give t2 a chance to wait on the lock, then set the flag
+              sleep 0.01
+              was_set = true
             end
+
+            t2 = Thread.new do
+              begin
+                sem.try_wait(10.0)
+              rescue Errno::ETIMEDOUT
+                # success
+              end
+            end
+
+            # t1 should set the flag and die while t2 is still waiting on the lock
+            t1.join
           end
 
-          # t1 should set the flag and die while t2 is still waiting on the lock
-          t1.join
+          was_set.must_equal true
+          (Time.now.to_f - start).must be_lt(0.1)
+
+          t2.join
         end
-
-        was_set.must_equal true
-        (Time.now.to_f - start).must be_lt(0.1)
-
-        t2.join
       end
     end
   end