diff --git a/cmake/cpu.cmake b/cmake/cpu.cmake
index c7d19b63..8843133b 100644
--- a/cmake/cpu.cmake
+++ b/cmake/cpu.cmake
@@ -2,7 +2,7 @@ if (NOT CMAKE_SYSTEM_PROCESSOR)
     message(WARNING "CMAKE_SYSTEM_PROCESSOR not defined")
 endif()
 
-if (CMAKE_SYSTEM_PROCESSOR MATCHES "^(x86_64|AMD64)$")
+if (CMAKE_SYSTEM_PROCESSOR MATCHES "^(x86_64|AMD64)$" AND CMAKE_SIZEOF_VOID_P EQUAL 8)
     add_definitions(/DRAPIDJSON_SSE2)
 else()
     set(WITH_SSE4_1 OFF)