Getting "an unspecified error has occurred" or "identifier 'result' is undefined" in Visual studio

Question

Hello, my project is working and do everything I need, but when i'm debugging it, in one of the locals I can't see the value but those messeges and a rex X from the left, I can see that the valuses in the "result" changed after the function but while the function is running it's like the watch/autos aren't recognize"result". i'd like for some help to understand what's wrong

Answer 1

Hi @Noa Halali , 

Welcome to Microsoft Q&A! 

Please try to disable Optimization: right-click on Project > Properties > Configuration Properties > C/C++ > Optimization > Optimization: Disabled (/Od). 

Sincerely,

Anna

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Answer 2

I have the same problem. For whatever reason it only happens with structs.
And even weirder: Only with the struct I return.

So in OPs example if in the function I do something like this:

Student unScramble(List lst){
    Student result;
    Student working;

    ...

    return result;
}

If I return result I can't debug result. But I can debug working.

If I return working it's vice versa.

I'm running in Debug mode.

Sincerly,

Kevin

Answer 3

The exact behavior described by @Kevin Mayrhofer still happens as of VS2022 17.7.5.

It's not possible to introspect on the values of returned struct objects using the debugger.