diff --git a/CMakeLists.txt b/CMakeLists.txt
index d8958bf9d..b9656ea50 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -179,9 +179,6 @@ add_definitions(-DSINGLETHREADED)
 set_property(DIRECTORY APPEND PROPERTY
     COMPILE_DEFINITIONS $<$<CONFIG:Debug>:_DEBUG> $<$<NOT:$<CONFIG:Debug>>:NDEBUG>)
 
-math(EXPR EMU_ARCH_BITS ${CMAKE_SIZEOF_VOID_P}*8)
-add_definitions(-DEMU_ARCH_BITS=${EMU_ARCH_BITS})
-
 # System imported libraries
 # ======================