From 2e715844bb14f57ce7f9db9ac957046b916853ee Mon Sep 17 00:00:00 2001
From: Howard Hinnant <howard.hinnant@gmail.com>
Date: Sat, 1 Aug 2015 16:41:03 -0400
Subject: [PATCH] Restrict the range of year: to within the range of
 chrono::minutes. * This prevents overflow when adding minutes to day_point  
 when minutes is stored in 32 bits. * Also added static checks on the range of
 hours and seconds.   If these static checks fire, the range of year should be
   further reduced. * This does not impact gcc at all.  It impacts clang only 
  when targeting 32 bit architectures.  And it fixes   overflow on Visual
 Studio. * Thanks much to https://github.com/gmcode for the herculean   effort
 in tracking this down.

---
 date.h | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/date.h b/date.h
index 89a159f..6b771f2 100644
--- a/date.h
+++ b/date.h
@@ -6,6 +6,7 @@
 // http://creativecommons.org/licenses/by/4.0/
 
 #include <chrono>
+#include <climits>
 #if !(__cplusplus >= 201402)
 #  include <cmath>
 #endif
@@ -1161,7 +1162,12 @@ inline
 year
 year::min() noexcept
 {
-    return year{std::numeric_limits<short>::min()};
+    using namespace std::chrono;
+    static_assert(sizeof(seconds)*CHAR_BIT >= 41, "seconds may overflow");
+    static_assert(sizeof(hours)*CHAR_BIT >= 30, "hours may overflow");
+    return sizeof(minutes)*CHAR_BIT < 34 ?
+        year{1970} + duration_cast<years>(minutes::min()) :
+        year{std::numeric_limits<short>::min()};
 }
 
 CONSTCD11
@@ -1169,7 +1175,12 @@ inline
 year
 year::max() noexcept
 {
-    return year{std::numeric_limits<short>::max()};
+    using namespace std::chrono;
+    static_assert(sizeof(seconds)*CHAR_BIT >= 41, "seconds may overflow");
+    static_assert(sizeof(hours)*CHAR_BIT >= 30, "hours may overflow");
+    return sizeof(minutes)*CHAR_BIT < 34 ?
+        year{1969} + duration_cast<years>(minutes::max()) :
+        year{std::numeric_limits<short>::max()};
 }
 
 CONSTCD11