Re: A proposal for a modern build-system

From: Boris Kolpackov (boris_at_[hidden])
Date: 2024-03-22 06:00:17

Hassan Sajjad via Boost <boost_at_[hidden]> writes:

> It supports drop-in header-files to header-units replacement. While
> compilers support processing a header-file as header-unit, no other
> build-system supports this feature.

That's incorrect: build2 had support for header units (with include
translation) from 2021:

https://build2.org/blog/build2-cxx20-modules-gcc.xhtml

(Funny enough that support was announced in Feb 2021 while I see the
first commit in the HMake repository was also made in Feb 2021, so
build2 had header unit support for as long as HMake existed ;-)).

And speaking of compilers, currently only GCC provides enough
build system integration (in the form of the module mapper) to
allow accurately supporting header units without making the
user specify the dependencies manually (or imposing equivalent
requirements like pre-compiling all the header units used by
the project upfront). For background, see:

https://developercommunity.visualstudio.com/t/scanDependencies-does-not-take-into-acc/10029154