diff --git a/include/etl/nullptr.h b/include/etl/nullptr.h
index 2e200787..9a0bffe7 100644
--- a/include/etl/nullptr.h
+++ b/include/etl/nullptr.h
@@ -33,7 +33,7 @@ SOFTWARE.
 
 #include "platform.h"
 
-#if defined(ARDUINO) || defined(AVR)
+#if defined(ARDUINO) || defined(__AVR__)
   #include <stddef.h>
 #else
   #include <cstddef>
diff --git a/test/vs2019/etl.vcxproj.filters b/test/vs2019/etl.vcxproj.filters
index 36af486d..3bc8262b 100644
--- a/test/vs2019/etl.vcxproj.filters
+++ b/test/vs2019/etl.vcxproj.filters
@@ -888,12 +888,12 @@
     <ClInclude Include="..\..\include\etl\flags.h">
       <Filter>ETL\Utilities</Filter>
     </ClInclude>
-    <ClInclude Include="..\..\include\etl\buffer_descriptors.h">
-      <Filter>ETL\Utilities</Filter>
-    </ClInclude>
     <ClInclude Include="..\..\include\etl\atomic\atomic_clang_sync.h">
       <Filter>ETL\Utilities\Atomic</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\include\etl\buffer_descriptors.h">
+      <Filter>ETL\Containers</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\main.cpp">