diff --git a/compiler-rt/lib/msan/tests/CMakeLists.txt b/compiler-rt/lib/msan/tests/CMakeLists.txt
--- a/compiler-rt/lib/msan/tests/CMakeLists.txt
+++ b/compiler-rt/lib/msan/tests/CMakeLists.txt
@@ -26,7 +26,6 @@
   )
 set(MSAN_UNITTEST_COMMON_CFLAGS
   -nostdinc++
-  -isystem ${COMPILER_RT_LIBCXX_PATH}/include
   ${COMPILER_RT_UNITTEST_CFLAGS}
   ${COMPILER_RT_GTEST_CFLAGS}
   -I${COMPILER_RT_SOURCE_DIR}/include
@@ -67,7 +66,8 @@
     KIND ${kind}
     COMPILE_DEPS ${MSAN_UNITTEST_HEADERS}
     DEPS gtest msan
-    CFLAGS ${MSAN_UNITTEST_INSTRUMENTED_CFLAGS} ${cflags}
+    CFLAGS -isystem ${CMAKE_CURRENT_BINARY_DIR}/../libcxx_msan_${arch}/include/c++/v1
+           ${MSAN_UNITTEST_INSTRUMENTED_CFLAGS} ${cflags}
   )
 endmacro()