Loading CLR 2.0 dlls in to CLR 4.0 process, any downsides?

Are 开发者_运维技巧there any downsides, like perf, or debugging capability reduction if I'm shoving in a dll linked with the 2.0 CLR?

I'd love to move all our sources to .NET 4.0, but some of our partners are using our base code in 2.0, which is forcing us to either keep multiple binaries of our stuff, or stay within 2.0 realms.

Any ideas on how to use MSBuild to make multiple copies of the same project in 2.0 and 4.0 would be awesome as well.

No, perf and debuggability is not going to be affected.

The only downside is that the assembly will run with .NET framework assemblies that it has never been tested with. The odds that this causes problems is very small but not nil. The .NET 4 assemblies have a handful of obscure bug fixes that alter behavior. And add a few bugs itself. These cases are way too obscure to list or take seriously.