--- embree-3.12.0/CMakeLists.txt.orig	2020-10-08 13:06:09.573257200 +0300
+++ embree-3.12.0/CMakeLists.txt	2020-10-08 13:07:16.344816300 +0300
@@ -198,10 +198,15 @@
     MESSAGE("Intel Compiler detected")
     INCLUDE (intel)
   ELSE()
+    IF(MINGW)
+      MESSAGE("GCC detected")
+      INCLUDE (gnu)
+    ELSE()
-    IF (EMBREE_ISA_AVX512KNL OR EMBREE_ISA_AVX512SKX)
-      MESSAGE(FATAL_ERROR "Microsoft Visual C++ Compiler does not support AVX512. Please use Intel Compiler or Clang.")
-    ENDIF()
-    INCLUDE (msvc)
+      IF (EMBREE_ISA_AVX512KNL OR EMBREE_ISA_AVX512SKX)
+        MESSAGE(FATAL_ERROR "Microsoft Visual C++ Compiler does not support AVX512. Please use Intel Compiler or Clang.")
+      ENDIF()
+      INCLUDE (msvc)
+    ENDIF()
   ENDIF()
 
 ELSE (WIN32)
--- embree-3.12.0/common/math/math.h.orig	2020-10-08 13:23:56.732826200 +0300
+++ embree-3.12.0/common/math/math.h	2020-10-08 13:24:09.816659600 +0300
@@ -13,7 +13,7 @@
 #include <immintrin.h>
 
 #if defined(__WIN32__)
-#if (__MSV_VER <= 1700)
+#if defined(_MSC_VER) && (_MSC_VER <= 1700)
 namespace std
 {
   __forceinline bool isinf ( const float x ) { return _finite(x) == 0; }
@@ -40,7 +40,7 @@
   __forceinline int   toInt  (const float& a) { return int(a); }
   __forceinline float toFloat(const int&   a) { return float(a); }
 
-#if defined(__WIN32__)
+#if defined(_MSC_VER)
   __forceinline bool finite ( const float x ) { return _finite(x) != 0; }
 #endif
 
@@ -86,7 +86,7 @@
     return _mm_cvtss_f32(c);
   }
 
-#if defined(__WIN32__) && (__MSC_VER <= 1700)
+#if defined(_MSC_VER) && (_MSC_VER <= 1700)
   __forceinline float nextafter(float x, float y) { if ((x<y) == (x>0)) return x*(1.1f+float(ulp)); else return x*(0.9f-float(ulp)); }
   __forceinline double nextafter(double x, double y) { return _nextafter(x, y); }
   __forceinline int roundf(float f) { return (int)(f + 0.5f); }
--- embree-3.12.0/common/sys/library.cpp.orig	2020-10-08 13:25:49.035618400 +0300
+++ embree-3.12.0/common/sys/library.cpp	2020-10-08 13:27:18.700305300 +0300
@@ -27,7 +27,7 @@
 
   /* returns address of a symbol from the library */
   void* getSymbol(lib_t lib, const std::string& sym) {
-    return GetProcAddress(HMODULE(lib),sym.c_str());
+    return (void *)GetProcAddress(HMODULE(lib),sym.c_str());
   }
 
   /* closes the shared library */
--- embree-3.12.0/common/sys/intrinsics.h.orig	2020-10-08 13:46:29.816139700 +0300
+++ embree-3.12.0/common/sys/intrinsics.h	2020-10-08 13:47:04.718594900 +0300
@@ -30,7 +30,9 @@
 #endif
 
 #if defined(__WIN32__)
+#  if !defined(NOMINMAX)
 #  define NOMINMAX
+#  endif
 #  include <windows.h>
 #endif
 
--- embree-3.12.0/include/embree3/rtcore_common.h.orig	2020-10-08 13:45:45.391426500 +0300
+++ embree-3.12.0/include/embree3/rtcore_common.h	2020-10-08 13:45:56.064816000 +0300
@@ -19,7 +19,7 @@
 #endif
 #endif
 
-#ifdef _WIN32
+#ifdef _MSC_VER
 #  define RTC_ALIGN(...) __declspec(align(__VA_ARGS__))
 #else
 #  define RTC_ALIGN(...) __attribute__((aligned(__VA_ARGS__)))
--- embree-3.12.0/common/tasking/taskschedulertbb.h.orig	2020-10-08 13:54:46.957437800 +0300
+++ embree-3.12.0/common/tasking/taskschedulertbb.h	2020-10-08 13:55:28.620373200 +0300
@@ -12,7 +12,9 @@
 #include "../sys/ref.h"
 
 #if defined(__WIN32__)
+#  if !defined(NOMINMAX)
 #  define NOMINMAX
+#  endif
 #endif
 
 // We need to define these to avoid implicit linkage against
--- embree-3.12.0/common/sys/sysinfo.cpp.orig	2020-10-08 14:04:36.119217500 +0300
+++ embree-3.12.0/common/sys/sysinfo.cpp	2020-10-08 14:05:22.213153600 +0300
@@ -177,7 +177,7 @@
 
   __noinline int64_t get_xcr0() 
   {
-#if defined (__WIN32__)
+#if defined (_MSC_VER)
     int64_t xcr0 = 0; // int64_t is workaround for compiler bug under VS2013, Win32
     xcr0 = _xgetbv(0);
     return xcr0;
@@ -211,7 +211,7 @@
     int cpuid_leaf_e1[4] = { 0,0,0,0 };
     if (nIds >= 1) __cpuid (cpuid_leaf_1,0x00000001);
 #if _WIN32
-#if _MSC_VER && (_MSC_FULL_VER < 160040219)
+#if defined(_MSC_VER) && (_MSC_FULL_VER < 160040219)
 #else
     if (nIds >= 7) __cpuidex(cpuid_leaf_7,0x00000007,0);
 #endif
--- embree-3.12.0/tutorials/common/tutorial/CMakeLists.txt.orig	2020-10-08 15:10:28.601395100 +0300
+++ embree-3.12.0/tutorials/common/tutorial/CMakeLists.txt	2020-10-08 15:10:32.753196700 +0300
@@ -26,7 +26,7 @@
   SET_PROPERTY(TARGET noise_ispc APPEND PROPERTY COMPILE_FLAGS " ${FLAGS_LOWEST}")
 ENDIF()
 
-IF (WIN32 AND NOT EMBREE_EXTERNAL_GLFW)
+IF (MSVC AND NOT EMBREE_EXTERNAL_GLFW)
 
   GET_FILENAME_COMPONENT(GLFW_DIR ${GLFW_LIBRARY} PATH)
   ADD_CUSTOM_COMMAND(TARGET tutorial POST_BUILD
--- embree-3.12.0/common/cmake/gnu.cmake.orig	2020-10-08 20:26:40.332913400 +0300
+++ embree-3.12.0/common/cmake/gnu.cmake	2020-10-08 20:30:01.359024200 +0300
@@ -39,8 +39,9 @@
 SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fvisibility-inlines-hidden") # makes all inline symbols hidden by default
 SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-strict-aliasing")        # disables strict aliasing rules
 SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-tree-vectorize")         # disable auto vectorizer
-SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D_FORTIFY_SOURCE=2")         # perform extra security checks for some standard library calls
+SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D_USE_MATH_DEFINES")
 IF (EMBREE_STACK_PROTECTOR)
+  SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D_FORTIFY_SOURCE=2")         # perform extra security checks for some standard library calls
   SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fstack-protector")           # protects against return address overrides
 ENDIF()
 MACRO(DISABLE_STACK_PROTECTOR_FOR_FILE file)
@@ -69,10 +70,12 @@
   SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")             # link against libc++ which supports C++11 features
 ELSE(APPLE)
   SET(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,--no-undefined") # issues link error for undefined symbols in shared library
+  IF (NOT MINGW)
   SET(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -z noexecstack")     # we do not need an executable stack
   SET(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -z relro -z now")    # re-arranges data sections to increase security
   SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -z noexecstack")           # we do not need an executable stack
   SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -z relro -z now")          # re-arranges data sections to increase security
   SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -pie")                     # enables position independent execution for executable
+  ENDIF ()
 ENDIF(APPLE)
 
--- embree-3.12.0/common/cmake/package.cmake.orig	2020-10-08 20:43:01.906336600 +0300
+++ embree-3.12.0/common/cmake/package.cmake	2020-10-08 20:45:40.283140100 +0300
@@ -24,7 +24,7 @@
 # Install MSVC runtime
 ##############################################################
 
-IF (WIN32)
+IF (MSVC)
   SET(CMAKE_INSTALL_SYSTEM_RUNTIME_LIBS_SKIP TRUE)
   INCLUDE(InstallRequiredSystemLibraries)
   LIST(FILTER CMAKE_INSTALL_SYSTEM_RUNTIME_LIBS INCLUDE REGEX ".*msvcp[0-9]+\.dll|.*vcruntime[0-9]+\.dll|.*vcruntime[0-9]+_[0-9]+\.dll")
@@ -36,7 +36,7 @@
 ##############################################################
 
 INSTALL(DIRECTORY include/embree3 DESTINATION ${CMAKE_INSTALL_INCLUDEDIR} COMPONENT devel)
-IF (NOT WIN32)
+IF (NOT MSVC)
   INSTALL(DIRECTORY man/man3 DESTINATION ${CMAKE_INSTALL_MANDIR} COMPONENT devel)
 ENDIF()
 
@@ -106,7 +106,7 @@
   ENDIF()
 ENDIF()
 
-IF (WIN32 OR EMBREE_ZIP_MODE)
+IF (MSVC OR EMBREE_ZIP_MODE)
   # for local "installs" and on Windows we want the cmake config files placed
   # in the install root, such that users can point the CMake variable
   # embree_DIR just to the install folder
@@ -116,7 +116,11 @@
 ELSE()
   SET(EMBREE_CMAKECONFIG_DIR "${CMAKE_INSTALL_LIBDIR}/cmake/embree-${EMBREE_VERSION}")
   SET(EMBREE_CMAKEEXPORT_DIR "${CMAKE_INSTALL_LIBDIR}/cmake/embree-${EMBREE_VERSION}")
-  FILE(RELATIVE_PATH EMBREE_RELATIV_ROOT_DIR "/${EMBREE_CMAKECONFIG_DIR}" "/")
+  IF (WIN32)
+    SET(EMBREE_RELATIV_ROOT_DIR "../../../")
+  ELSE()
+    FILE(RELATIVE_PATH EMBREE_RELATIV_ROOT_DIR "/${EMBREE_CMAKECONFIG_DIR}" "/")
+  ENDIF()
 ENDIF()
 
 CONFIGURE_FILE(common/cmake/embree-config.cmake embree-config-install.cmake @ONLY)
--- embree-3.12.0/common/math/constants.h.orig	2020-10-08 20:54:58.498103100 +0300
+++ embree-3.12.0/common/math/constants.h	2020-10-08 20:55:08.724746100 +0300
@@ -7,8 +7,7 @@
 
 #include <limits>
 
-#define _USE_MATH_DEFINES
-#include <math.h> // using cmath causes issues under Windows
+#include <cmath> // using cmath causes issues under Windows
 #include <cfloat>
 #include <climits>