Only full shared or full static build

[JohanMabille]

This PR simplifies the cmake and removes an hybrid build that might be problematic because of mixing different runtimes.

• Removed the BUILD_STATIC_DEPS option
• The BUILD_STATIC option is now equivalent to the old BUILD_STATIC_DEPS
• Target linkage is now the same as the build type (so we do not mix static and shared anymore)
• In case we build both shared and static libraries, binaries (micromamba and mamba-package) will link with the shared libraries by default. To change that, the options MICROMAMBA_LINKAGE and MAMBA_PACKAGE_LINKAGE can be set to STATIC

[jonashaag]

fyi @pavelzw

[wolfv]

Looks good to me!

[AntoinePrv]

Should we take this opportunity to introduce an prefix on options: MAMBA_BUILD_STATIC etc. ?

[JohanMabille]

I don't know, MAMBA_BUILD_MICROMAMBA sounds a bit weird. And there is already a lot to type to build micromamba for instance

[AntoinePrv]

MAMBA_BUILD_MICRO?

[JohanMabille]

still weird. And I don't think we need this prefix as long as this is not used as a framework in another repo building with cmake.

[AntoinePrv]

Should there be s single option, where true means static, false means shared?

[wolfv]

yeah I think we should default to SHARED

[JohanMabille]

I think BUILD_SHARED and BUILD_STATIC are more expressive. And you may want to build both at the same time.

[AntoinePrv]

Ha right, it's too target, not one that transmute

[JohanMabille]

yeah I think we should default to SHARED

But in that case if you want to build the static version only, you need to pass two options ( BUILD_SHARED=OFF and BUILD_STATIC=ON) instead of a single one

[JohanMabille]

I can add options like:

• BUILD_ALL_SHARED
• BUILD_ALL_STATIC

The only question is should we build tests with these targets? (sometimes you just want to build micromamba for reproducing an issue or debugging, and you don't want tot build the tests).