diff --git a/stdlib/pp/0/pp.rbs b/stdlib/pp/0/pp.rbs
index 1ff8090d9f..c543439a5c 100644
--- a/stdlib/pp/0/pp.rbs
+++ b/stdlib/pp/0/pp.rbs
@@ -53,6 +53,11 @@
 # Tanaka Akira <akr@fsij.org>
 #
 class PP < PrettyPrint
+  # <!-- rdoc-file=lib/pp.rb -->
+  # The version string
+  #
+  VERSION: String
+
   interface _PrettyPrint
     def pretty_print: (untyped q) -> untyped
 
@@ -124,6 +129,14 @@ class PP < PrettyPrint
     #
     def pp: (_PrettyPrint obj) -> untyped
 
+    # <!--
+    #   rdoc-file=lib/pp.rb
+    #   - pp_hash_pair(k, v)
+    # -->
+    # A pretty print for a pair of Hash
+    #
+    def pp_hash_pair: (untyped k, untyped v) -> void
+
     # <!--
     #   rdoc-file=lib/pp.rb
     #   - object_group(obj) { || ... }
diff --git a/stdlib/shellwords/0/shellwords.rbs b/stdlib/shellwords/0/shellwords.rbs
index e2d206240e..abea66536c 100644
--- a/stdlib/shellwords/0/shellwords.rbs
+++ b/stdlib/shellwords/0/shellwords.rbs
@@ -64,6 +64,10 @@
 # *   Akinori MUSHA <knu@iDaemons.org> (current maintainer)
 #
 module Shellwords
+  # <!-- rdoc-file=lib/shellwords.rb -->
+  # The version number string.
+  #
+  VERSION: String
   # <!--
   #   rdoc-file=lib/shellwords.rb
   #   - shellescape(str)
diff --git a/stdlib/strscan/0/string_scanner.rbs b/stdlib/strscan/0/string_scanner.rbs
index 42accd2209..8fddca5cea 100644
--- a/stdlib/strscan/0/string_scanner.rbs
+++ b/stdlib/strscan/0/string_scanner.rbs
@@ -1646,3 +1646,9 @@ end
 StringScanner::Id: String
 
 StringScanner::Version: String
+
+# <!-- rdoc-file=ext/strscan/strscan.c -->
+# The error class for StringScanner. See StringScanner#unscan.
+#
+class StringScanner::Error < StandardError
+end
diff --git a/test/stdlib/PP_test.rb b/test/stdlib/PP_test.rb
index 3068883396..b5f1562f6d 100644
--- a/test/stdlib/PP_test.rb
+++ b/test/stdlib/PP_test.rb
@@ -7,6 +7,10 @@ class PPSingletonTest < Test::Unit::TestCase
   library "pp"
   testing "singleton(::PP)"
 
+  def test_version
+    assert_const_type "String", "PP::VERSION"
+  end
+
   def test_pp
     assert_send_type "(::PP::_PrettyPrint obj, ?::PP::_LeftShift out, ?::Integer width) -> untyped",
                      PP, :pp, Object.new, ''.dup
@@ -105,6 +109,11 @@ def test_pp_hash
     assert_send_type "(untyped obj) -> untyped",
                      PP.new, :pp_hash, {}
   end
+
+  def test_pp_hash_pair
+    assert_send_type "(untyped k, untyped v) -> void",
+                     PP.new, :pp_hash_pair, :a, 1
+  end
 end
 
 class PP::ObjectMixinTest < Test::Unit::TestCase
diff --git a/test/stdlib/Shellwords_test.rb b/test/stdlib/Shellwords_test.rb
index df593caaad..66ee9421cc 100644
--- a/test/stdlib/Shellwords_test.rb
+++ b/test/stdlib/Shellwords_test.rb
@@ -7,6 +7,10 @@ class ShellwordsSingletonTest < Test::Unit::TestCase
   library "shellwords"
   testing "singleton(::Shellwords)"
 
+  def test_version
+    assert_const_type "String", "Shellwords::VERSION"
+  end
+
   def test_shellescape
     assert_send_type  "(::String str) -> ::String",
                       Shellwords, :shellescape, "shell"
diff --git a/test/stdlib/StringScanner_test.rb b/test/stdlib/StringScanner_test.rb
index 1a8b7cdce5..a5102980e3 100644
--- a/test/stdlib/StringScanner_test.rb
+++ b/test/stdlib/StringScanner_test.rb
@@ -18,6 +18,10 @@ def test_must_C_version
     assert_send_type "() -> singleton(::StringScanner)",
                      StringScanner, :must_C_version
   end
+
+  def test_error
+    assert_const_type "Class", "StringScanner::Error"
+  end
 end
 
 class StringScannerTest < Test::Unit::TestCase