What does adding masm targets do under the hood

If in Visual Studio when you right-click a C/C++-project in the Solution Explorer, you choose Build Customizations…, the following dialog will be presented:

If you check the item for masm, the following changes will be done to your .vcxproj file:

<!-- inside the ImportGroup labeled ExtensionSettings adds: -->
<ImportGroup Label="ExtensionSettings">
  <Import Project="$(VCTargetsPath)\BuildCustomizations\masm.props" />
</ImportGroup>
<!-- inside the ImportGroup labeled ExtensionTargets adds: -->
<ImportGroup Label="ExtensionTargets">
  <Import Project="$(VCTargetsPath)\BuildCustomizations\masm.targets" />
</ImportGroup>

The items will then appear as:

<ItemGroup>
  <MASM Include="foobar.asm" />
</ItemGroup>

// Oliver

PS: Mostly meant as a reminder for myself.