[cfe-dev] Chaining clang::Modules

[Axel Naumann]

Hi!

I know I am walking on fragile grounds. But they are just too
interesting, so let me ask nonetheless :-)

I have a module core.pcm that contains Core.h. When generating big.pcm
(which contains Big.h which in turn #include-s Core.h) I want the
Preprocessor and the ASTWriter to make use of core.pcm - for instance to
not have to merge the modules when loading.

What's the best approach here? I don't manage to convince the ASTWriter
to use the chaining mechanism (in analogy to the chaining of PCHs); the
amount of registered "sub-"modules (core and big = 2) does not
correspond to the amount of modules written - which is only big.pcm
which does not have submodules and thus 1, as defined by ASTWriter's
getNumberOfModules().

It seems the ASTWriter expects me to create big.pcm as a super-module
with core.pcm as its submodule. The problem is that I will also generate
bigger.pcm and huge.pcm that would all like to reuse core.pcm, meaning
core.pcm is the submodule of many.

So is the submodule layout really appropriate here?

Cheers, Axel.