diff --git a/NEWS.md b/NEWS.md
index c6bcce74e338f2..0b622064720f22 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -182,9 +182,11 @@ The following default gems are updated.
 
 * RubyGems 4.0.0.dev
 * bundler 4.0.0.dev
+* date 3.5.0
 * erb 5.1.3
 * etc 1.4.6
 * fcntl 1.3.0
+* fileutils 1.8.0
 * io-console 0.8.1
 * io-nonblock 0.3.2
 * io-wait 0.3.2
@@ -197,6 +199,7 @@ The following default gems are updated.
 * resolv 0.6.2
 * stringio 3.1.8.dev
 * strscan 3.1.6.dev
+* timeout 0.4.4
 * uri 1.0.4
 * weakref 0.1.4
 * zlib 3.2.2
diff --git a/doc/maintainers.md b/doc/maintainers.md
index fdd7697ee6b370..244912cb20c9ca 100644
--- a/doc/maintainers.md
+++ b/doc/maintainers.md
@@ -622,6 +622,12 @@ It may needs to make consensus on ruby-core/ruby-dev before making major changes
 * https://github.com/ruby/fiddle
 * https://rubygems.org/gems/fiddle
 
+#### repl_type_completor
+
+* Tomoya Ishida ([tompng])
+* https://github.com/ruby/repl_type_completor
+* https://rubygems.org/gems/repl_type_completor
+
 ## Platform Maintainers
 
 ### mswin64 (Microsoft Windows)
diff --git a/ext/date/lib/date.rb b/ext/date/lib/date.rb
index aa630eb6d172b5..b33f6e65f466b0 100644
--- a/ext/date/lib/date.rb
+++ b/ext/date/lib/date.rb
@@ -4,7 +4,7 @@
 require 'date_core'
 
 class Date
-  VERSION = "3.4.1" # :nodoc:
+  VERSION = "3.5.0" # :nodoc:
 
   # call-seq:
   #   infinite? -> false
diff --git a/ext/io/wait/wait.c b/ext/io/wait/wait.c
index 88e6dd2af1fb58..bec04cb727e054 100644
--- a/ext/io/wait/wait.c
+++ b/ext/io/wait/wait.c
@@ -84,7 +84,7 @@ io_nread(VALUE io)
     ioctl_arg n;
 
     GetOpenFile(io, fptr);
-    rb_io_check_readable(fptr);
+    rb_io_check_char_readable(fptr);
     len = rb_io_read_pending(fptr);
     if (len > 0) return INT2FIX(len);
 
@@ -143,7 +143,7 @@ io_ready_p(VALUE io)
 #endif
 
     GetOpenFile(io, fptr);
-    rb_io_check_readable(fptr);
+    rb_io_check_char_readable(fptr);
     if (rb_io_read_pending(fptr)) return Qtrue;
 
 #ifndef HAVE_RB_IO_WAIT
@@ -178,7 +178,7 @@ io_wait_readable(int argc, VALUE *argv, VALUE io)
 #endif
 
     GetOpenFile(io, fptr);
-    rb_io_check_readable(fptr);
+    rb_io_check_char_readable(fptr);
 
 #ifndef HAVE_RB_IO_WAIT
     tv = get_timeout(argc, argv, &timerec);
@@ -252,7 +252,7 @@ io_wait_priority(int argc, VALUE *argv, VALUE io)
     rb_io_t *fptr = NULL;
 
     RB_IO_POINTER(io, fptr);
-    rb_io_check_readable(fptr);
+    rb_io_check_char_readable(fptr);
 
     if (rb_io_read_pending(fptr)) return Qtrue;
 
diff --git a/io.c b/io.c
index d412d14963bded..78ac0bb2c65d9e 100644
--- a/io.c
+++ b/io.c
@@ -9832,7 +9832,7 @@ io_wait_readable(int argc, VALUE *argv, VALUE io)
     rb_io_t *fptr;
 
     RB_IO_POINTER(io, fptr);
-    rb_io_check_readable(fptr);
+    rb_io_check_char_readable(fptr);
 
     if (rb_io_read_pending(fptr)) return Qtrue;
 
@@ -9879,7 +9879,7 @@ io_wait_priority(int argc, VALUE *argv, VALUE io)
     rb_io_t *fptr = NULL;
 
     RB_IO_POINTER(io, fptr);
-    rb_io_check_readable(fptr);
+    rb_io_check_char_readable(fptr);
 
     if (rb_io_read_pending(fptr)) return Qtrue;
 
diff --git a/lib/fileutils.rb b/lib/fileutils.rb
index 6ef71d75ef39f3..0706e007ca4979 100644
--- a/lib/fileutils.rb
+++ b/lib/fileutils.rb
@@ -181,7 +181,7 @@
 #
 module FileUtils
   # The version number.
-  VERSION = "1.7.3"
+  VERSION = "1.8.0"
 
   def self.private_module_function(name)   #:nodoc:
     module_function name
diff --git a/lib/timeout.rb b/lib/timeout.rb
index f5f232ad2ae072..e1f0a4a78c6f59 100644
--- a/lib/timeout.rb
+++ b/lib/timeout.rb
@@ -20,7 +20,7 @@
 
 module Timeout
   # The version
-  VERSION = "0.4.3"
+  VERSION = "0.4.4"
 
   # Internal error raised to when a timeout is triggered.
   class ExitException < Exception
diff --git a/test/date/test_date_conv.rb b/test/date/test_date_conv.rb
index 772fbee9a4e6ce..8d810844355956 100644
--- a/test/date/test_date_conv.rb
+++ b/test/date/test_date_conv.rb
@@ -82,21 +82,17 @@ def test_to_time__from_datetime
     assert_equal([1582, 10, 13, 1, 2, 3, 456789],
 		 [t.year, t.mon, t.mday, t.hour, t.min, t.sec, t.usec])
 
-    if Time.allocate.respond_to?(:nsec)
-      d = DateTime.new(2004, 9, 19, 1, 2, 3, 0) + 456789123.to_r/86400000000000
-      t = d.to_time.utc
-      assert_equal([2004, 9, 19, 1, 2, 3, 456789123],
-		   [t.year, t.mon, t.mday, t.hour, t.min, t.sec, t.nsec])
-    end
+    d = DateTime.new(2004, 9, 19, 1, 2, 3, 0) + 456789123.to_r/86400000000000
+    t = d.to_time.utc
+    assert_equal([2004, 9, 19, 1, 2, 3, 456789123],
+		 [t.year, t.mon, t.mday, t.hour, t.min, t.sec, t.nsec])
 
     # TruffleRuby does not support more than nanoseconds
     unless RUBY_ENGINE == 'truffleruby'
-      if Time.allocate.respond_to?(:subsec)
-        d = DateTime.new(2004, 9, 19, 1, 2, 3, 0) + 456789123456789123.to_r/86400000000000000000000
-        t = d.to_time.utc
-        assert_equal([2004, 9, 19, 1, 2, 3, Rational(456789123456789123,1000000000000000000)],
-         [t.year, t.mon, t.mday, t.hour, t.min, t.sec, t.subsec])
-      end
+      d = DateTime.new(2004, 9, 19, 1, 2, 3, 0) + 456789123456789123.to_r/86400000000000000000000
+      t = d.to_time.utc
+      assert_equal([2004, 9, 19, 1, 2, 3, Rational(456789123456789123,1000000000000000000)],
+                   [t.year, t.mon, t.mday, t.hour, t.min, t.sec, t.subsec])
     end
   end
 
diff --git a/test/io/wait/test_io_wait_uncommon.rb b/test/io/wait/test_io_wait_uncommon.rb
index 0f922f4e24b34f..0f97ac35d9124e 100644
--- a/test/io/wait/test_io_wait_uncommon.rb
+++ b/test/io/wait/test_io_wait_uncommon.rb
@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 require 'test/unit'
+require 'io/wait'
 
 # test uncommon device types to check portability problems
 # We may optimize IO#wait_*able for non-Linux kernels in the future
@@ -74,4 +75,33 @@ def test_wait_readable_zero
   def test_wait_writable_null
     check_dev(IO::NULL, :wait_writable)
   end
+
+  def test_after_ungetc_ready?
+    check_dev(IO::NULL, mode: "r") {|fp|
+      assert_respond_to fp, :ready?
+      fp.ungetc(?a)
+      assert_predicate fp, :ready?
+    }
+  end
+
+  def test_after_ungetc_wait_readable
+    check_dev(IO::NULL, mode: "r") {|fp|
+      fp.ungetc(?a)
+      assert_predicate fp, :wait_readable
+    }
+  end
+
+  def test_after_ungetc_in_text_ready?
+    check_dev(IO::NULL, mode: "rt") {|fp|
+      fp.ungetc(?a)
+      assert_predicate fp, :ready?
+    }
+  end
+
+  def test_after_ungetc_in_text_wait_readable
+    check_dev(IO::NULL, mode: "rt") {|fp|
+      fp.ungetc(?a)
+      assert_predicate fp, :wait_readable
+    }
+  end
 end
diff --git a/test/ruby/test_namespace.rb b/test/ruby/test_namespace.rb
index bfbbe38e051ab2..5a014ad7148a51 100644
--- a/test/ruby/test_namespace.rb
+++ b/test/ruby/test_namespace.rb
@@ -690,5 +690,9 @@ def test_root_and_main_methods
       assert !$LOADED_FEATURES.include?("/tmp/barbaz")
       assert !Object.const_defined?(:FooClass)
     end;
+  ensure
+    tmp = ENV["TMPDIR"] || ENV["TMP"] || Etc.systmpdir || "/tmp"
+    pat = "_ruby_ns_*."+RbConfig::CONFIG["DLEXT"]
+    File.unlink(*Dir.glob(pat, base: tmp).map {|so| "#{tmp}/#{so}"})
   end
 end
diff --git a/win32/win32.c b/win32/win32.c
index c13c4e17320268..e7dfe2b065975a 100644
--- a/win32/win32.c
+++ b/win32/win32.c
@@ -4724,27 +4724,36 @@ waitpid(rb_pid_t pid, int *stat_loc, int options)
 
 #include <sys/timeb.h>
 
+/* License: Ruby's */
+#define filetime_unit (10UL * 1000 * 1000)
+#define filetime_diff_days ((1970-1601)*3652425UL/10000)
+#define filetime_diff_secs (filetime_diff_days * (24ULL * 60 * 60))
+#define unix_to_filetime(sec) (((sec) + filetime_diff_secs) * filetime_unit)
+#define filetime_unix_offset unix_to_filetime(0ULL)
+
+/* License: Ruby's */
+typedef union {
+    /* FILETIME and ULARGE_INTEGER::u are the same layout */
+    FILETIME ft;
+    ULARGE_INTEGER i;
+} FILETIME_INTEGER;
+
 /* License: Ruby's */
 /* split FILETIME value into UNIX time and sub-seconds in NT ticks */
 static time_t
 filetime_split(const FILETIME* ft, long *subsec)
 {
-    ULARGE_INTEGER tmp;
-    unsigned LONG_LONG lt;
-    const unsigned LONG_LONG subsec_unit = (unsigned LONG_LONG)10 * 1000 * 1000;
-
-    tmp.LowPart = ft->dwLowDateTime;
-    tmp.HighPart = ft->dwHighDateTime;
-    lt = tmp.QuadPart;
+    FILETIME_INTEGER fi = {.ft = *ft};
+    ULONGLONG lt = fi.i.QuadPart;
 
     /* lt is now 100-nanosec intervals since 1601/01/01 00:00:00 UTC,
        convert it into UNIX time (since 1970/01/01 00:00:00 UTC).
        the first leap second is at 1972/06/30, so we doesn't need to think
        about it. */
-    lt -= (LONG_LONG)((1970-1601)*365.2425) * 24 * 60 * 60 * subsec_unit;
+    lt -= unix_to_filetime(0);
 
-    *subsec = (long)(lt % subsec_unit);
-    return (time_t)(lt / subsec_unit);
+    *subsec = (long)(lt % filetime_unit);
+    return (time_t)(lt / filetime_unit);
 }
 
 /* License: Ruby's */
@@ -4762,15 +4771,6 @@ gettimeofday(struct timeval *tv, struct timezone *tz)
 }
 
 /* License: Ruby's */
-static FILETIME
-filetimes_plus(FILETIME t1, FILETIME t2)
-{
-    ULARGE_INTEGER i1 = {.u = {.LowPart = t1.dwLowDateTime, .HighPart = t1.dwHighDateTime}};
-    ULARGE_INTEGER i2 = {.u = {.LowPart = t2.dwLowDateTime, .HighPart = t2.dwHighDateTime}};
-    ULARGE_INTEGER i = {.QuadPart = i1.QuadPart + i2.QuadPart};
-    return (FILETIME){.dwLowDateTime = i.LowPart, .dwHighDateTime = i.HighPart};
-}
-
 static void
 filetime_to_timespec(FILETIME ft, struct timespec *sp)
 {
@@ -4800,11 +4800,11 @@ clock_gettime(clockid_t clock_id, struct timespec *sp)
         {
             LARGE_INTEGER freq;
             LARGE_INTEGER count;
-            if (!QueryPerformanceFrequency(&freq)) {
+            if (UNLIKELY(!QueryPerformanceFrequency(&freq))) {
                 errno = map_errno(GetLastError());
                 return -1;
             }
-            if (!QueryPerformanceCounter(&count)) {
+            if (UNLIKELY(!QueryPerformanceCounter(&count))) {
                 errno = map_errno(GetLastError());
                 return -1;
             }
@@ -4818,19 +4818,20 @@ clock_gettime(clockid_t clock_id, struct timespec *sp)
       case CLOCK_PROCESS_CPUTIME_ID:
       case CLOCK_THREAD_CPUTIME_ID:
         {
-            FILETIME ct, et, kt, ut;
+            FILETIME_INTEGER c, e, k, u, total;
             BOOL ok;
             if (clock_id == CLOCK_PROCESS_CPUTIME_ID) {
-                ok = GetProcessTimes(GetCurrentProcess(), &ct, &et, &kt, &ut);
+                ok = GetProcessTimes(GetCurrentProcess(), &c.ft, &e.ft, &k.ft, &u.ft);
             }
             else {
-                ok = GetThreadTimes(GetCurrentThread(), &ct, &et, &kt, &ut);
+                ok = GetThreadTimes(GetCurrentThread(), &c.ft, &e.ft, &k.ft, &u.ft);
             }
-            if (!ok) {
+            if (UNLIKELY(!ok)) {
                 errno = map_errno(GetLastError());
                 return -1;
             }
-            filetime_to_timespec(filetimes_plus(kt, ut), sp);
+            total.i.QuadPart = k.i.QuadPart + u.i.QuadPart;
+            filetime_to_timespec(total.ft, sp);
             return 0;
         }
       default:
@@ -7598,7 +7599,7 @@ unixtime_to_filetime(time_t time, FILETIME *ft)
 {
     ULARGE_INTEGER tmp;
 
-    tmp.QuadPart = ((LONG_LONG)time + (LONG_LONG)((1970-1601)*365.2425) * 24 * 60 * 60) * 10 * 1000 * 1000;
+    tmp.QuadPart = unix_to_filetime((ULONGLONG)time);
     ft->dwLowDateTime = tmp.LowPart;
     ft->dwHighDateTime = tmp.HighPart;
     return 0;
@@ -7611,7 +7612,7 @@ timespec_to_filetime(const struct timespec *ts, FILETIME *ft)
 {
     ULARGE_INTEGER tmp;
 
-    tmp.QuadPart = ((LONG_LONG)ts->tv_sec + (LONG_LONG)((1970-1601)*365.2425) * 24 * 60 * 60) * 10 * 1000 * 1000;
+    tmp.QuadPart = unix_to_filetime((ULONGLONG)ts->tv_sec);
     tmp.QuadPart += ts->tv_nsec / 100;
     ft->dwLowDateTime = tmp.LowPart;
     ft->dwHighDateTime = tmp.HighPart;