Boost Libraries and Dropping C++ Language Support

From: Glen Fernandes (glen.fernandes_at_[hidden])
Date: 2023-02-22 23:10:39

*Boost library authors and maintainers are free to drop support for old C++
standards in their libraries, at any time. *
This includes libraries that other Boost libraries depend on. It even
includes core libraries like Boost.Core or Boost.Static_Assert.

We ask that maintainers do the right thing by all our users (which may
include other Boost libraries) by announcing a future breakage *at least
two Boost releases in advance*.

When that eventual release time arrives, if Boost libraries are broken in
older standards modes due to another Boost library dropping support, it
will not block the Boost release.

This means that we do not need to announce "Boost is dropping C++03"
because Boost doesn't "support C++03" now as it is.

It means that you, maintainer of Boost.X, should realize that you are free
to announce that "Boost.X is dropping C++XY in version 1.Z" as you see fit.

Boost in its infancy thrived because its libraries were on the cutting
edge. Boost libraries today should similarly not be confined simply because
other Boost libraries have chosen to depend on them.

Furthermore, as Boost release managers we support authors exercising this
freedom, and do not intend to impose any restrictions on what language
support they must maintain.

We will add a page to the Boost website stating the above formally.

-- The release team (Glen Fernandes, Marshall Clow)