diff --git a/spec/ruby/core/kernel/caller_locations_spec.rb b/spec/ruby/core/kernel/caller_locations_spec.rb
index c4e0084085..8050b5b3ab 100644
--- a/spec/ruby/core/kernel/caller_locations_spec.rb
+++ b/spec/ruby/core/kernel/caller_locations_spec.rb
@@ -65,4 +65,16 @@ describe 'Kernel#caller_locations' do
   it "must return the same locations when called with 1..-1 and when called with no arguments" do
     caller_locations.map(&:to_s).should == caller_locations(1..-1).map(&:to_s)
   end
+
+  guard -> { Kernel.instance_method(:tap).source_location } do
+    it "includes core library methods defined in Ruby" do
+      file, line = Kernel.instance_method(:tap).source_location
+      file.should.start_with?('<internal:')
+
+      loc = nil
+      tap { loc = caller_locations(1, 1)[0] }
+      loc.label.should == "tap"
+      loc.path.should.start_with? "<internal:"
+    end
+  end
 end
diff --git a/spec/ruby/core/kernel/caller_spec.rb b/spec/ruby/core/kernel/caller_spec.rb
index b71060770c..06e9ea6fc8 100644
--- a/spec/ruby/core/kernel/caller_spec.rb
+++ b/spec/ruby/core/kernel/caller_spec.rb
@@ -51,4 +51,16 @@ describe 'Kernel#caller' do
       locations2.map(&:to_s).should == locations1[2..-1].map(&:to_s)
     end
   end
+
+  guard -> { Kernel.instance_method(:tap).source_location } do
+    it "includes core library methods defined in Ruby" do
+      file, line = Kernel.instance_method(:tap).source_location
+      file.should.start_with?('<internal:')
+
+      loc = nil
+      tap { loc = caller(1, 1)[0] }
+      loc.should.end_with? "in `tap'"
+      loc.should.start_with? "<internal:"
+    end
+  end
 end