diff --git a/tools/hc-gen/CMakeLists.txt b/tools/hc-gen/CMakeLists.txt
index 1075c8cfeeed740fe3dd60bb6f8a0333665ab2e5..6ec32032f66d19604d0a5a38a3dd62cca1808006 100644
--- a/tools/hc-gen/CMakeLists.txt
+++ b/tools/hc-gen/CMakeLists.txt
@@ -6,10 +6,9 @@ set(CMAKE_CXX_STANDARD 14)
 set(CMAKE_CXX_FLAGS "-Wall")
 
 if (CMAKE_SYSTEM_NAME MATCHES "Linux")
-    add_definitions(-D OS_LINUX)
+    add_definitions(-D OS_UNIX)
 elseif (CMAKE_SYSTEM_NAME MATCHES "Windows")
-    add_definitions(-D OS_WIN)
-    add_definitions(-D MINGW32)
+    add_definitions(-D OS_MINGW)
 endif (CMAKE_SYSTEM_NAME MATCHES "Linux")
 
 set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O2 -s")