Index: cmake/OpenMPTesting.cmake
===================================================================
--- cmake/OpenMPTesting.cmake
+++ cmake/OpenMPTesting.cmake
@@ -99,7 +99,7 @@
   # project is built which is too late for detecting the compiler...
   file(MAKE_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/DetectTestCompiler)
   execute_process(
-    COMMAND ${CMAKE_COMMAND} ${CMAKE_CURRENT_LIST_DIR}/DetectTestCompiler
+    COMMAND ${CMAKE_COMMAND} -G${CMAKE_GENERATOR} ${CMAKE_CURRENT_LIST_DIR}/DetectTestCompiler
       -DCMAKE_C_COMPILER=${OPENMP_TEST_C_COMPILER}
       -DCMAKE_CXX_COMPILER=${OPENMP_TEST_CXX_COMPILER}
     WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/DetectTestCompiler
Index: runtime/cmake/LibompHandleFlags.cmake
===================================================================
--- runtime/cmake/LibompHandleFlags.cmake
+++ runtime/cmake/LibompHandleFlags.cmake
@@ -50,6 +50,7 @@
   libomp_append(flags_local /GS LIBOMP_HAVE_GS_FLAG)
   libomp_append(flags_local /EHsc LIBOMP_HAVE_EHSC_FLAG)
   libomp_append(flags_local /Oy- LIBOMP_HAVE_OY__FLAG)
+  libomp_append(flags_local -mrtm LIBOMP_HAVE_MRTM_FLAG)
   # Intel(R) C Compiler flags
   libomp_append(flags_local /Qsafeseh LIBOMP_HAVE_QSAFESEH_FLAG)
   libomp_append(flags_local -Qoption,cpp,--extended_float_types LIBOMP_HAVE_EXTENDED_FLOAT_TYPES_FLAG)
Index: runtime/cmake/config-ix.cmake
===================================================================
--- runtime/cmake/config-ix.cmake
+++ runtime/cmake/config-ix.cmake
@@ -73,13 +73,18 @@
 libomp_check_architecture_flag(-mmic LIBOMP_HAVE_MMIC_FLAG)
 libomp_check_architecture_flag(-m32 LIBOMP_HAVE_M32_FLAG)
 if(WIN32)
-  # Check Windows MSVC style flags.
-  check_c_compiler_flag(/TP LIBOMP_HAVE_TP_FLAG)
-  check_cxx_compiler_flag(/EHsc LIBOMP_HAVE_EHSC_FLAG)
-  check_cxx_compiler_flag(/GS LIBOMP_HAVE_GS_FLAG)
-  check_cxx_compiler_flag(/Oy- LIBOMP_HAVE_Oy__FLAG)
-  check_cxx_compiler_flag(/arch:SSE2 LIBOMP_HAVE_ARCH_SSE2_FLAG)
-  check_cxx_compiler_flag(/Qsafeseh LIBOMP_HAVE_QSAFESEH_FLAG)
+  if(MSVC)
+    # Check Windows MSVC style flags.
+    check_c_compiler_flag(/TP LIBOMP_HAVE_TP_FLAG)
+    check_cxx_compiler_flag(/EHsc LIBOMP_HAVE_EHSC_FLAG)
+    check_cxx_compiler_flag(/GS LIBOMP_HAVE_GS_FLAG)
+    check_cxx_compiler_flag(/Oy- LIBOMP_HAVE_Oy__FLAG)
+    check_cxx_compiler_flag(/arch:SSE2 LIBOMP_HAVE_ARCH_SSE2_FLAG)
+    check_cxx_compiler_flag(/Qsafeseh LIBOMP_HAVE_QSAFESEH_FLAG)
+  endif()
+  if(CMAKE_C_COMPILER_ID STREQUAL "Clang")
+    check_c_compiler_flag(-mrtm LIBOMP_HAVE_MRTM_FLAG)
+  endif()
   # It is difficult to create a dummy masm assembly file
   # and then check the MASM assembler to see if these flags exist and work,
   # so we assume they do for Windows.
Index: runtime/src/dllexports
===================================================================
--- runtime/src/dllexports
+++ runtime/src/dllexports
@@ -558,9 +558,6 @@
     omp_thread_mem_alloc                   DATA
 %endif # OMP_50
 
-%ifdef OMP_50
-    omp_control_tool                        891
-%endif # OMP_50
 %ifndef stub
     # Ordinals between 900 and 999 are reserved
 
Index: runtime/src/kmp.h
===================================================================
--- runtime/src/kmp.h
+++ runtime/src/kmp.h
@@ -560,7 +560,7 @@
 
 // GROUP_AFFINITY is already defined for _MSC_VER>=1600 (VS2010 and later).
 #if KMP_OS_WINDOWS
-#if _MSC_VER < 1600
+#if _MSC_VER < 1600 && !defined(__MINGW32__)
 typedef struct GROUP_AFFINITY {
   KAFFINITY Mask;
   WORD Group;
Index: runtime/src/kmp_dispatch.cpp
===================================================================
--- runtime/src/kmp_dispatch.cpp
+++ runtime/src/kmp_dispatch.cpp
@@ -24,7 +24,7 @@
 #include "kmp_itt.h"
 #include "kmp_stats.h"
 #include "kmp_str.h"
-#if KMP_OS_WINDOWS && KMP_ARCH_X86
+#if KMP_OS_WINDOWS && KMP_ARCH_X86 && !defined(__clang__)
 #include <float.h>
 #endif
 #include "kmp_lock.h"
@@ -478,7 +478,7 @@
         /* commonly used term: (2 nproc - 1)/(2 nproc) */
         DBL x;
 
-#if KMP_OS_WINDOWS && KMP_ARCH_X86
+#if KMP_OS_WINDOWS && KMP_ARCH_X86 && !defined(__clang__)
         /* Linux* OS already has 64-bit computation by default for long double,
            and on Windows* OS on Intel(R) 64, /Qlong_double doesn't work. On
            Windows* OS on IA-32 architecture, we need to set precision to 64-bit
@@ -573,7 +573,7 @@
         pr->u.p.count = tc - __kmp_dispatch_guided_remaining(
                                  tc, GUIDED_ANALYTICAL_WORKAROUND, cross) -
                         cross * chunk;
-#if KMP_OS_WINDOWS && KMP_ARCH_X86
+#if KMP_OS_WINDOWS && KMP_ARCH_X86 && !defined(__clang__)
         // restore FPCW
         _control87(oldFpcw, _MCW_PC);
 #endif
@@ -1625,7 +1625,7 @@
   case kmp_sch_guided_analytical_chunked: {
     T chunkspec = pr->u.p.parm1;
     UT chunkIdx;
-#if KMP_OS_WINDOWS && KMP_ARCH_X86
+#if KMP_OS_WINDOWS && KMP_ARCH_X86 && !defined(__clang__)
     /* for storing original FPCW value for Windows* OS on
        IA-32 architecture 8-byte version */
     unsigned int oldFpcw;
@@ -1662,7 +1662,7 @@
    Windows* OS.
    This check works around the possible effect that init != 0 for chunkIdx == 0.
  */
-#if KMP_OS_WINDOWS && KMP_ARCH_X86
+#if KMP_OS_WINDOWS && KMP_ARCH_X86 && !defined(__clang__)
         /* If we haven't already done so, save original
            FPCW and set precision to 64-bit, as Windows* OS
            on IA-32 architecture defaults to 53-bit */
@@ -1690,7 +1690,7 @@
         } // if
       } // if
     } // while (1)
-#if KMP_OS_WINDOWS && KMP_ARCH_X86
+#if KMP_OS_WINDOWS && KMP_ARCH_X86 && !defined(__clang__)
     /* restore FPCW if necessary
        AC: check fpcwSet flag first because oldFpcw can be uninitialized here
     */
Index: runtime/src/kmp_lock.cpp
===================================================================
--- runtime/src/kmp_lock.cpp
+++ runtime/src/kmp_lock.cpp
@@ -1716,7 +1716,7 @@
 
 /* RTM Adaptive locks */
 
-#if KMP_COMPILER_ICC && __INTEL_COMPILER >= 1300
+#if (KMP_COMPILER_ICC && __INTEL_COMPILER >= 1300) || defined(__clang__)
 
 #include <immintrin.h>
 #define SOFT_ABORT_MASK (_XABORT_RETRY | _XABORT_CONFLICT | _XABORT_EXPLICIT)
Index: runtime/src/kmp_os.h
===================================================================
--- runtime/src/kmp_os.h
+++ runtime/src/kmp_os.h
@@ -246,7 +246,7 @@
 
 #define KMP_EXPORT extern /* export declaration in guide libraries */
 
-#if __GNUC__ >= 4
+#if __GNUC__ >= 4 && !defined(__MINGW32__)
 #define __forceinline __inline
 #endif
 
@@ -296,7 +296,7 @@
 #define KMP_NORETURN __attribute__((noreturn))
 #endif
 
-#if KMP_OS_WINDOWS
+#if KMP_OS_WINDOWS && !defined(__clang__)
 #define KMP_ALIGN(bytes) __declspec(align(bytes))
 #define KMP_THREAD_LOCAL __declspec(thread)
 #define KMP_ALIAS /* Nothing */
Index: runtime/src/kmp_platform.h
===================================================================
--- runtime/src/kmp_platform.h
+++ runtime/src/kmp_platform.h
@@ -82,7 +82,7 @@
 #define KMP_ARCH_MIPS64 0
 
 #if KMP_OS_WINDOWS
-#if defined _M_AMD64
+#if defined(_M_AMD64) || defined(__x86_64)
 #undef KMP_ARCH_X86_64
 #define KMP_ARCH_X86_64 1
 #else
Index: runtime/src/kmp_safe_c_api.h
===================================================================
--- runtime/src/kmp_safe_c_api.h
+++ runtime/src/kmp_safe_c_api.h
@@ -15,7 +15,7 @@
 
 // Not every unsafe call listed here is handled now, but keeping everything
 // in one place should be handy for future maintenance.
-#if KMP_OS_WINDOWS
+#if KMP_OS_WINDOWS && !defined(__MINGW32__)
 
 #define RSIZE_MAX_STR (4UL << 10) // 4KB
 
Index: runtime/src/kmp_wrapper_getpid.h
===================================================================
--- runtime/src/kmp_wrapper_getpid.h
+++ runtime/src/kmp_wrapper_getpid.h
@@ -39,7 +39,9 @@
 // "process.h".
 #include <process.h>
 // Let us simulate Unix.
+#ifndef __MINGW32__
 typedef int pid_t;
+#endif
 #define getpid _getpid
 #define __kmp_gettid() GetCurrentThreadId()
 
Index: runtime/src/kmp_wrapper_malloc.h
===================================================================
--- runtime/src/kmp_wrapper_malloc.h
+++ runtime/src/kmp_wrapper_malloc.h
@@ -93,7 +93,9 @@
 // Include alloca() declaration.
 #if KMP_OS_WINDOWS
 #include <malloc.h> // Windows* OS: _alloca() declared in "malloc.h".
+#ifndef __MINGW32__
 #define alloca _alloca // Allow to use alloca() with no underscore.
+#endif
 #elif KMP_OS_FREEBSD || KMP_OS_NETBSD
 // Declared in "stdlib.h".
 #elif KMP_OS_UNIX
Index: runtime/src/libomp.rc.var
===================================================================
--- runtime/src/libomp.rc.var
+++ runtime/src/libomp.rc.var
@@ -11,7 +11,7 @@
 ////===----------------------------------------------------------------------===//
 //
 
-#include "winres.h"
+#include "winresrc.h"
 #include "kmp_config.h"
 
 LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US    // English (U.S.) resources
Index: runtime/src/z_Windows_NT_util.cpp
===================================================================
--- runtime/src/z_Windows_NT_util.cpp
+++ runtime/src/z_Windows_NT_util.cpp
@@ -887,6 +887,7 @@
   return 1e9 * __kmp_win32_tick * now.QuadPart;
 }
 
+extern "C"
 void *__stdcall __kmp_launch_worker(void *arg) {
   volatile void *stack_data;
   void *exit_val;