From 094ca0281e1ddbfcd9d7c36363cea2222885527b Mon Sep 17 00:00:00 2001
From: akr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Thu, 10 Jun 2010 14:10:25 +0000
Subject: [PATCH] * time.c (rb_localtime_r2): refine localtime overflow check
 for   FreeBSD 6.4.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@28256 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog                 |  5 +++++
 test/ruby/test_time_tz.rb |  6 ++++--
 time.c                    | 14 +++++++++++---
 3 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 20172e0c11..ed651ab396 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Jun 10 23:05:44 2010  Tanaka Akira  <akr@fsij.org>
+
+	* time.c (rb_localtime_r2): refine localtime overflow check for
+	  FreeBSD 6.4.
+
 Thu Jun 10 09:10:08 2010  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* io.c (rb_io_putc): documentation updated to mention putc would
diff --git a/test/ruby/test_time_tz.rb b/test/ruby/test_time_tz.rb
index ea7b51d5d2..4e781cd820 100644
--- a/test/ruby/test_time_tz.rb
+++ b/test/ruby/test_time_tz.rb
@@ -153,8 +153,10 @@ class TestTimeTZ < Test::Unit::TestCase
     sample.each {|tz, u, l, gmtoff|
       with_tz(tz) {
         expected = "%04d-%02d-%02d %02d:%02d:%02d %s" % (l+[format_gmtoff(gmtoff)])
-        t = Time.utc(*u).localtime
-        assert_equal(expected, time_to_s(t), "TZ=#{tz} Time.utc(#{u.map(&:inspect).join(', ')}).localtime")
+        mesg = "TZ=#{tz} Time.utc(#{u.map(&:inspect).join(', ')}).localtime"
+        t = nil
+        assert_nothing_raised(mesg) { t = Time.utc(*u).localtime }
+        assert_equal(expected, time_to_s(t), mesg)
         assert_equal(gmtoff, t.gmtoff)
       }
     }
diff --git a/time.c b/time.c
index 58d8475855..5acc64345c 100644
--- a/time.c
+++ b/time.c
@@ -870,9 +870,17 @@ rb_localtime_r2(const time_t *t, struct tm *result)
     result = rb_localtime_r(t, result);
 #if defined(HAVE_MKTIME) && defined(LOCALTIME_OVERFLOW_PROBLEM)
     if (result) {
-	time_t t2 = mktime(result);
-	if (*t != t2)
-	    result = NULL;
+        int gmtoff1 = 0;
+        int gmtoff2 = 0;
+#  if defined(HAVE_STRUCT_TM_TM_GMTOFF)
+        gmtoff1 = result->tm_gmtoff;
+#  endif
+        time_t t2 = mktime(result);
+#  if defined(HAVE_STRUCT_TM_TM_GMTOFF)
+        gmtoff2 = result->tm_gmtoff;
+#  endif
+        if (*t + gmtoff1 != t2 + gmtoff2)
+            result = NULL;
     }
 #endif
     return result;