How can I look at class/struct layout in VS?

Development Platform & Builds Debugging, Optimization, & Profiling
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I’m currently working on some optimizations for async IO and I need to look at the layout of some structs. To do that I usually use the /d1reportSingleClassLayout compiler switch, see Bing . Is there any easy way to add that to Engine\Source\Runtime\Core\Private\Serialization\AsyncIOSystemBase.cpp or its unity build file with UBT?

Thanks.

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On Engine\Source\Programs\UnrealBuildTool\Windows\VCToolChain.cs the compiler flags are set. For every CompileAction the CommandArguments string contains all the arguments. If you add for example if you convert this:
CompileAction.CommandArguments = Arguments + FileArguments + CompileEnvironment.Config.AdditionalArguments;
To this it will print the layout of the FAsyncIORequest struct:
CompileAction.CommandArguments = Arguments + FileArguments + " /d1reportSingleClassLayoutFAsyncIORequest" + CompileEnvironment.Config.AdditionalArguments;

This is a horrible hack and proper way should be devised but it works for my purpose. Part of the issue this isn’t so easy to integrate is that every CompileAction is related to a unity build file so you would have to know ahead of time what is the unity build file that contains the cpp you can to add the argument to.