diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9b394c3..87cd2ad 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -26,6 +26,10 @@
     set(CMAKE_C_FLAGS_CHECK       "-Werror -Os")
 endif(CMAKE_COMPILER_IS_CLANG)
 
+if(MSVC)
+    set(CMAKE_C_FLAGS_CHECK       "/WX")
+endif(MSVC)
+
 set(CMAKE_BUILD_TYPE ${CMAKE_BUILD_TYPE}
     CACHE STRING "Choose the type of build: None Debug Release Coverage ASan ASanDbg MemSan MemSanDbg Check CheckFull"
     FORCE)
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 068d715..8023803 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -33,6 +33,10 @@
     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-unused-function")
 endif(CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_CLANG)
 
+if(MSVC)
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} /w") # no warnings here
+endif(MSVC)
+
 add_test_suite(aes aes.ecb)
 add_test_suite(aes aes.cbc)
 add_test_suite(aes aes.cfb)