Allow switching between build-in and Clang Code Model per project

I have some legacy microcontroller projects that use proprietary compiler extensions like @far or @inline as function modifiers.

I can work with them really good with the build-in code model, like I have done for years.

Last year I started working with the Clang Code Model, which works quite well if it understands the whole source code. The proprietary extensions make the Clang Code Model quite useless: Semantic highlighting, Find Usages, Goto Definition work very restricted, if at all.

It would really help me, if I could just switch back to the build-in code model for these projects, as I could work quite good with it. I know similar requests from the forum, but for now the only way is to turn off Clang completely.