3 files changed, 19 insertions, 2 deletions
diff --git a/activesupport/lib/active_support/notifications/instrumenter.rb b/activesupport/lib/active_support/notifications/instrumenter.rb
index f8344912bb..9184f8f54b 100644
--- a/activesupport/lib/active_support/notifications/instrumenter.rb
+++ b/activesupport/lib/active_support/notifications/instrumenter.rb
@@ -55,6 +55,11 @@ module ActiveSupport
       attr_reader :name, :time, :transaction_id, :payload, :children
       attr_accessor :end
 
+      def self.clock_gettime_supported? # :nodoc:
+        defined?(Process::CLOCK_PROCESS_CPUTIME_ID) &&
+        !Gem.win_platform?
+      end
+
       def initialize(name, start, ending, transaction_id, payload)
         @name           = name
         @payload        = payload.dup
@@ -130,7 +135,7 @@ module ActiveSupport
           Process.clock_gettime(Process::CLOCK_MONOTONIC)
         end
 
-        if defined?(Process::CLOCK_PROCESS_CPUTIME_ID)
+        if clock_gettime_supported?
           def now_cpu
             Process.clock_gettime(Process::CLOCK_PROCESS_CPUTIME_ID)
           end
diff --git a/activesupport/lib/active_support/testing/parallelization.rb b/activesupport/lib/active_support/testing/parallelization.rb
index 9c8dffa9d8..8de01eb19b 100644
--- a/activesupport/lib/active_support/testing/parallelization.rb
+++ b/activesupport/lib/active_support/testing/parallelization.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
 require "drb"
-require "drb/unix"
+require "drb/unix" unless Gem.win_platform?
 require "active_support/core_ext/module/attribute_accessors"
 
 module ActiveSupport
@@ -15,6 +15,8 @@ module ActiveSupport
         end
 
         def record(reporter, result)
+          raise DRb::DRbConnError if result.is_a?(DRb::DRbUnknown)
+
           reporter.synchronize do
             reporter.record(result)
           end
diff --git a/activesupport/test/multibyte_chars_test.rb b/activesupport/test/multibyte_chars_test.rb
index f87099566b..5f4e3f3fd3 100644
--- a/activesupport/test/multibyte_chars_test.rb
+++ b/activesupport/test/multibyte_chars_test.rb
@@ -772,6 +772,16 @@ class MultibyteCharsExtrasTest < ActiveSupport::TestCase
     assert_deprecated { ActiveSupport::Multibyte::Unicode.swapcase("") }
   end
 
+  def test_normalize_non_unicode_string
+    # Fullwidth Latin Capital Letter A in Windows 31J
+    str = "\u{ff21}".encode(Encoding::Windows_31J)
+    assert_raise Encoding::CompatibilityError do
+      ActiveSupport::Deprecation.silence do
+        ActiveSupport::Multibyte::Unicode.normalize(str)
+      end
+    end
+  end
+
   private
 
     def string_from_classes(classes)