diff --git a/compiler-rt/lib/profile/CMakeLists.txt b/compiler-rt/lib/profile/CMakeLists.txt
--- a/compiler-rt/lib/profile/CMakeLists.txt
+++ b/compiler-rt/lib/profile/CMakeLists.txt
@@ -1,11 +1,11 @@
 
 CHECK_CXX_SOURCE_COMPILES("
-#ifdef _MSC_VER
+#ifdef _WIN32
 #include <Intrin.h> /* Workaround for PR19898. */
 #include <windows.h>
 #endif
 int main() {
-#ifdef _MSC_VER
+#ifdef _WIN32
         volatile LONG val = 1;
         MemoryBarrier();
         InterlockedCompareExchange(&val, 0, 1);
diff --git a/compiler-rt/lib/profile/InstrProfilingPort.h b/compiler-rt/lib/profile/InstrProfilingPort.h
--- a/compiler-rt/lib/profile/InstrProfilingPort.h
+++ b/compiler-rt/lib/profile/InstrProfilingPort.h
@@ -53,7 +53,7 @@
 #endif
 
 #if COMPILER_RT_HAS_ATOMICS == 1
-#ifdef _MSC_VER
+#ifdef _WIN32
 #include <windows.h>
 #if _MSC_VER < 1900
 #define snprintf _snprintf
@@ -73,7 +73,7 @@
   (DomType *)InterlockedExchangeAdd((LONG volatile *)&PtrVar,                  \
                                     (LONG)sizeof(DomType) * PtrIncr)
 #endif
-#else /* !defined(_MSC_VER) */
+#else /* !defined(_WIN32) */
 #define COMPILER_RT_BOOL_CMPXCHG(Ptr, OldV, NewV)                              \
   __sync_bool_compare_and_swap(Ptr, OldV, NewV)
 #define COMPILER_RT_PTR_FETCH_ADD(DomType, PtrVar, PtrIncr)                    \