Patch for c++20 modules raw support

[ChemistAion]

This is work of @Cheaterdev, details are in:
#145
#146

[ChemistAion]

This one-liner (by @Cheaterdev) allows to work with c++20 modules flawlessly, could you please do some regression tests on this?
...since @belkiss (involved in these discussions) stopped responding :|

[jspelletier]

belkiss is no longer working at ubisoft, sadly. I will take a look at this in the next few days.

[ChemistAion]

@jspelletier: ack, I appreciate it... waiting for yours analysis

[jspelletier]

this modifies a bunch of vcxproj and adds a lots of unwanted project reference to our vcxproj.

Why don't you instead set ExportAdditionalLibrariesEvenForStaticLib to true in your configurations? Would be equivalent to the if condition that you removed(I think). Or if this is not possible and doesn't work, would need to hide this new behavior behind some feature flag(possibly a new bool in Project.Configuration)

[ChemistAion]

I will conduct some tests based on your recommendation, give me a few hours.

[Cheaterdev]

this modifies a bunch of vcxproj and adds a lots of unwanted project reference to our vcxproj.

Why don't you instead set ExportAdditionalLibrariesEvenForStaticLib to true in your configurations? Would be equivalent to the if condition that you removed(I think). Or if this is not possible and doesn't work, would need to hide this new behavior behind some feature flag(possibly a new bool in Project.Configuration)

Because when having multiple projects with modules it starts exporting lib files as well and linker is going crazy - a lot of duplicates. We just need proper references between projects, nothing more.

[Cheaterdev]

Thought it was merged... still I struggle with the official version. I really need to have the dependencies between projects. Just dependencies, nothing more. ExportAdditionalLibrariesEvenForStaticLib has side effect - it exports the same code in every lib that uses it and in the end - there is a lot of linker messages with multiple symbols.

I believe you don't want to have the dependencies between libraries so code could compile in parallel without need of waiting of compilation results from dependency projects. But its an optimization of specific case. I believe it shouldn't be by default.

If you don't want break current behavior - maybe its better to introduce conf.ForceProjectDependencies for that?

Edit: Just saw other topics and even forgot I had the same proposition before. Still hoping for other MR submit :)