Suppress MSVC warning about unsigned negation

PiperOrigin-RevId: 306583087
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2e55557..c84804a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,6 +31,11 @@
   ADD_DEFINITIONS(-DXNN_ENABLE_ASSEMBLY=0)
 ENDIF()
 
+IF(MSVC)
+  # Disable "unary minus operator applied to unsigned type, result still unsigned" warning
+  ADD_COMPILE_OPTIONS("/wd4146")
+ENDIF()
+
 # ---[ Build flags
 IF(NOT CMAKE_SYSTEM_PROCESSOR)
   IF(IOS)