On 11/3/20 2:15 PM, Nathan Sidwell wrote:
> Here are the new options, along with the C++ lang-spec changes.
>
> Modules is enabled by -fmodules-ts, it is not implicitly enabled by
> -std=c++20. Usually that's the only option you need to add for a
> module-aware build.
>
> to build a header unit you can either add -fmodule-header to a c++
> build, or you can set the language to be c++-header and add -fmodules-ts:
>
> g++ -x c++-header -fmodules-ts my-header-file
>
> to search the user or system include paths select c++-user-header of
> c++-system-header as the language.
>
> enabling -fmodules-ts will disable PCH, they do not play well
> together. There is a potential issue down the road when we implicitly
> enable modules. At that point building a header-unit could become
> indistinguishable from building a PCH. Perhaps we should consider
> phasing in an explicit PCH option?
In a modules capable world, how much value still exists with the old PCH
scheme? The old PCH scheme can't work in some enviroments anyway
(anyone using ASLR & PIE).
I'm going to assume the spec changs are OK. My brain always melts when
I start looking at them.
OK
Jeff
