From 6a427ac4b6be5406d2d42ff25f10121bb36835cd Mon Sep 17 00:00:00 2001
From: "Niall Douglas (s [underscore] sourceforge {at} nedprod [dot] com)"
 <spamtrap@nowhere.com>
Date: Mon, 16 Feb 2015 18:03:46 +0000
Subject: [PATCH] Fix physical_concurrency() on win32.

---
 src/win32/thread.cpp | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/src/win32/thread.cpp b/src/win32/thread.cpp
index aae37ccf..ded62056 100644
--- a/src/win32/thread.cpp
+++ b/src/win32/thread.cpp
@@ -529,11 +529,8 @@ namespace boost
 
     unsigned thread::physical_concurrency() BOOST_NOEXCEPT
     {
-// a bit too strict: Windows XP with SP3 would be sufficient
-#if BOOST_PLAT_WINDOWS_RUNTIME                                    \
-    || ( BOOST_USE_WINAPI_VERSION <= BOOST_WINAPI_VERSION_WINXP ) \
-    || ( defined(__MINGW32__) && !defined(__MINGW64__) )
-        return 0;
+#if BOOST_PLAT_WINDOWS_RUNTIME
+        return hardware_concurrency();
 #else
         unsigned cores = 0;
         DWORD size = 0;