UINT_MAX not expanded to typemax(Cuint)

[vchuravy]

https://github.com/flux-framework/flux-core/blob/ed8a7d2f14320fa8b2d5f5377f117eceb205b065/src/common/libidset/idset.h#L32

got expanded to:

const IDSET_INVALID_ID = UINT_MAX - 1

on current master

[Gnimuc]

This is possible if we also do a dependency analysis on those macro identifiers.

[melonedo]

It seems that UINT_MAX depends on __INT_MAX__, which is not defined in the headers. Maybe we have to add default macro definitions too.
https://stackoverflow.com/questions/58111142/where-is-the-macro-int-max-defined

[Gnimuc]

For now, macros are skipped in the dependency searching for identifiers.

https://github.com/JuliaInterop/Clang.jl/blob/master/src/generator/macro.jl#L174-L179

In general, macro support is hard to be done in an elegant way with libclang. The main reason is libclang doesn't expose enough info about tokens.

I think we should not invest too much time in this. Once ClangCompiler.jl hits a good coverage rate of Clang API, we can make full use of Clang's parser/preprocessor/lexer API. As for the OSPP project, it's OK to ignore those macro-related goals.

[JBlaschke]

I see the same for INT_MAX: #401