[cfe-dev] Executing multiple FrontendActions on a CompilerInstance

[via cfe-dev]

I came to learn that somehow, without any extra setup, only one 
FrontendAction can be executed on a CompilerInstance. See my question 
here [1] on stackoverflow for the details. What I'd like to know is: is 
it possible to run more than one FrontendAction on a CompilerInstance 
and if so, how? If not, why is this not possible?

Note that the second time a FrontendAction is run, an assert failure 
occurs somewhere in SourceManager and/or FileManager regarding FileIDs 
or something. This makes me think that I need to reset some state 
somewhere in SourceManager or FileManager attached to the 
CompilerInstance, but I am not a clang developer so I wouldn't know 
right away what the correct course of action is.