diff --git a/CMakeLists.txt b/CMakeLists.txt
index 77e5398b6a..4e5fdba791 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -164,6 +164,8 @@ if(TARGET_ARCH MATCHES "^(ARM|arm|aarch)")
   else()
     add_definitions(-DPNG_ARM_NEON_OPT=0)
   endif()
+else()
+  add_definitions(-DPNG_ARM_NEON_OPT=0)
 endif()
 
 # Set definitions and sources for PowerPC.