"Treat all warnings as errors except..." in Visual Studio

Question

You can add a WarningsNotAsErrors-tag in the project file.

<PropertyGroup>
    ...
    ...
    <WarningsNotAsErrors>618,1030,1701,1702</WarningsNotAsErrors>
</PropertyGroup>

Note: 612 and 618 are both warnings about Obsolete, don't know the difference but the project i'm working on is reporting Obsolete with warning 618.

/warnaserror /warnaserror-:618

or more specifically, in your case:

/warnaserror /warnaserror-:612,1030,1701,1702

this should treat all warnings as errors except for the ones in your comma separated list

In Visual Studio 2022 we have a new Project Properties UI which includes an editor for this.

Under Build | Errors and Warnings if you set Treat warnings as errors to All, then another property appears which allows you to exempt specific warnings from being treated as errors:

This will add the following property to your project:

<WarningsNotAsErrors>618,1030,1701,1702</WarningsNotAsErrors>

Why do you want to keep seeing warnings that you are not treating as errors? I am confused about why this is desirable - either you fix them or you don't.

Would two different build/solution files work - or a script to copy one and then so modify the warnings/warning level be suitable. It seems that perhaps you want some executions of the compiler to squawk, but others you want to keep going.

So different compiler switches seems like a good way to go. You could do this with different targets - one labeled debug or release and the others labeled suitably about the warnings.

I'm using treat warnings as errors.

In a rare cases, when some acceptable warning shows up (i.e. referencing obsolete member, or missing documentation on XML serialization classes), then it has to be explicitly suppressed with #pragma disable (and optionally reason for not having a clean code could be provided as a comment along).

Presence of this directive also allows to find out, who accepted this warning violation (by "blame" action of version control) in case there are some questions.