diff --git a/compiler-rt/CMakeLists.txt b/compiler-rt/CMakeLists.txt
--- a/compiler-rt/CMakeLists.txt
+++ b/compiler-rt/CMakeLists.txt
@@ -124,7 +124,7 @@
 endif()
 pythonize_bool(ANDROID)
 
-set(ANDROID_NDK_VERSION 18
+set(ANDROID_NDK_VERSION 21
     CACHE STRING "Set this to the Android NDK version that you are using")
 
 set(COMPILER_RT_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR})