From 4ec95d621ada1ffe9df742e0afee00679ce137ad Mon Sep 17 00:00:00 2001
From: Martijn Berger <martijn.berger@gmail.com>
Date: Thu, 31 Mar 2016 13:45:33 +0200
Subject: [PATCH] CMAKE / msvc openmp, delay loading of openmp dll so we can
 set environment variable before it is loaded

---
 CMakeLists.txt           | 11 +++++++++++
 source/creator/creator.c |  5 +++++
 2 files changed, 16 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4a03e8fa86e..99c07996598 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1308,6 +1308,17 @@ elseif(WIN32)
 
 		set(PLATFORM_LINKFLAGS_DEBUG "/IGNORE:4099 /NODEFAULTLIB:libcmt.lib /NODEFAULTLIB:libc.lib")
 
+		# Use dynamic loading for OpenMP
+		if(WITH_OPENMP)
+			if(MSVC_VERSION EQUAL 1800)
+				set(OPENMP_DLL_NAME "vcomp120")
+			else()
+				set(OPENMP_DLL_NAME "vcomp140")
+			endif()
+			set(PLATFORM_LINKFLAGS "${PLATFORM_LINKFLAGS} /DELAYLOAD:${OPENMP_DLL_NAME}.dll delayimp.lib")
+			set(PLATFORM_LINKFLAGS_DEBUG "${PLATFORM_LINKFLAGS_DEBUG} /DELAYLOAD::${OPENMP_DLL_NAME}d.dll delayimp.lib")
+		endif()
+
 		if(NOT DEFINED LIBDIR)
 
 			# Setup 64bit and 64bit windows systems
diff --git a/source/creator/creator.c b/source/creator/creator.c
index 2c2af7c199a..1010c9f06c8 100644
--- a/source/creator/creator.c
+++ b/source/creator/creator.c
@@ -205,6 +205,11 @@ int main(
 
 
 #ifdef WIN32
+	/* We delay loading of openmp so we can set the policy here. */
+# if defined(_MSC_VER)
+	_putenv_s("OMP_WAIT_POLICY", "PASSIVE");
+# endif
+
 	/* FMA3 support in the 2013 CRT is broken on Vista and Windows 7 RTM (fixed in SP1). Just disable it. */
 #  if defined(_MSC_VER) && defined(_M_X64)
 	_set_FMA3_enable(0);