diff --git a/ruby-2.5.0-Disable-Tokyo-TZ-tests.patch b/ruby-2.5.0-Disable-Tokyo-TZ-tests.patch
new file mode 100644
index 0000000..01632eb
--- /dev/null
+++ b/ruby-2.5.0-Disable-Tokyo-TZ-tests.patch
@@ -0,0 +1,30 @@
+diff --git a/test/ruby/test_time_tz.rb b/test/ruby/test_time_tz.rb
+index 20a57fe7dd..5b9e5a8bde 100644
+--- a/test/ruby/test_time_tz.rb
++++ b/test/ruby/test_time_tz.rb
+@@ -126,8 +126,8 @@ def test_asia_singapore
+ 
+   def test_asia_tokyo
+     with_tz(tz="Asia/Tokyo") {
+-      assert_time_constructor(tz, "1951-05-06 03:00:00 +1000", :local, [1951,5,6,2,0,0])
+-      assert_time_constructor(tz, "1951-05-06 03:59:59 +1000", :local, [1951,5,6,2,59,59])
++#      assert_time_constructor(tz, "1951-05-06 03:00:00 +1000", :local, [1951,5,6,2,0,0])
++#      assert_time_constructor(tz, "1951-05-06 03:59:59 +1000", :local, [1951,5,6,2,59,59])
+       assert_time_constructor(tz, "2010-06-10 06:13:28 +0900", :local, [2010,6,10,6,13,28])
+     }
+   end
+@@ -329,10 +329,10 @@ def self.gen_zdump_test(data)
+ Asia/Singapore  Sun Aug  8 16:30:00 1965 UTC = Mon Aug  9 00:00:00 1965 SGT isdst=0 gmtoff=27000
+ Asia/Singapore  Thu Dec 31 16:29:59 1981 UTC = Thu Dec 31 23:59:59 1981 SGT isdst=0 gmtoff=27000
+ Asia/Singapore  Thu Dec 31 16:30:00 1981 UTC = Fri Jan  1 00:30:00 1982 SGT isdst=0 gmtoff=28800
+-Asia/Tokyo  Sat May  5 16:59:59 1951 UTC = Sun May  6 01:59:59 1951 JST isdst=0 gmtoff=32400
+-Asia/Tokyo  Sat May  5 17:00:00 1951 UTC = Sun May  6 03:00:00 1951 JDT isdst=1 gmtoff=36000
+-Asia/Tokyo  Fri Sep  7 15:59:59 1951 UTC = Sat Sep  8 01:59:59 1951 JDT isdst=1 gmtoff=36000
+-Asia/Tokyo  Fri Sep  7 16:00:00 1951 UTC = Sat Sep  8 01:00:00 1951 JST isdst=0 gmtoff=32400
++#Asia/Tokyo  Sat May  5 16:59:59 1951 UTC = Sun May  6 01:59:59 1951 JST isdst=0 gmtoff=32400
++#Asia/Tokyo  Sat May  5 17:00:00 1951 UTC = Sun May  6 03:00:00 1951 JDT isdst=1 gmtoff=36000
++#Asia/Tokyo  Fri Sep  7 15:59:59 1951 UTC = Sat Sep  8 01:59:59 1951 JDT isdst=1 gmtoff=36000
++#Asia/Tokyo  Fri Sep  7 16:00:00 1951 UTC = Sat Sep  8 01:00:00 1951 JST isdst=0 gmtoff=32400
+ America/St_Johns  Sun Mar 11 03:30:59 2007 UTC = Sun Mar 11 00:00:59 2007 NST isdst=0 gmtoff=-12600
+ America/St_Johns  Sun Mar 11 03:31:00 2007 UTC = Sun Mar 11 01:01:00 2007 NDT isdst=1 gmtoff=-9000
+ America/St_Johns  Sun Nov  4 02:30:59 2007 UTC = Sun Nov  4 00:00:59 2007 NDT isdst=1 gmtoff=-9000
diff --git a/ruby.spec b/ruby.spec
index a4fecc0..268aacd 100644
--- a/ruby.spec
+++ b/ruby.spec
@@ -139,6 +139,9 @@ Patch10: ruby-2.5.0-Add-Gem.operating_system_defaults.patch
 # Fix segfault during generating documentation.
 # https://bugs.ruby-lang.org/issues/14343
 Patch11: ruby-2.5.0-parse.y-assignable_error.patch
+# Recent tzdata change breaks Ruby test suite.
+# https://bugs.ruby-lang.org/issues/14438
+Patch12: ruby-2.5.0-Disable-Tokyo-TZ-tests.patch
 
 Requires: %{name}-libs%{?_isa} = %{version}-%{release}
 Suggests: rubypick
@@ -523,6 +526,7 @@ rm -rf ext/fiddle/libffi*
 %patch9 -p1
 %patch10 -p1
 %patch11 -p1
+%patch12 -p1
 
 # Provide an example of usage of the tapset:
 cp -a %{SOURCE3} .