`include-what-you-use` diagnostics, in practice, are specific to
the environment's compiler and standard library. Update includes
to satisfy IWYU for our CI job under Debian 13. Some patterns:
* Types named in virtual `override` signatures no longer require
includes since the overridden signature already names them.
* A function argument's type needs to be included even if its constructor
is called only by implicit conversion. For example, constructing a
`std::function` from a lambda now requires `<functional>`.
* Some prior mysterious `<type_traits>` inclusions are no longer required.
The generator does a lot of tricks in order to make the "rebuild-bff"
target up-to-date immediately after the generation. We can skip all of
those during "TryCompile" runs, which should reduce configure time.
When CMAKE_FASTBUILD_USE_RELATIVE_PATHS is set -
use relative paths for Unity nodes as well as for include directories.
It makes it possible to share cache across different location of
the same repo (or potentially across different machines)
Right now, all IDE projects are located at the top level which makes it pretty messy when there are a lot of them.
With this change the generated IDE project will more closely mimic existing folder structure in the project.
List of changes:
1. Remove unneeded aliases
2. Don't write VS Solution on Apple
3. Use external script to perform clean
4. Fix small bug when empty environment was
resulting in invalid file.
It greatly reduces the size of .fdb file and
makes FASTBuild run much faster in different cases.
There's no control over the object base name implemented in the
FASTBuild generator. Rather than expecting some half-supported behavior,
just ignore it completely there.
Similarly, Xcode ends up making its own object paths internally
regardless of what CMake would like.
Compilation is complicated. Caching / distribution is even more
complicated. Sometimes there are bugs (in compilers as well as in
FASTBuild), so export the option to disable those features for CMake
targets.
