The Coverity compiler doesn't support C++2a yet, and thus doesn't
even recognize concept keywords. To allow serenity to be built and
analyzed on such compilers, add a fallback underdef to perform
the same template restriction based on AK::EnableIf<..> meta
programming.
Note: Coverity does seem to (annoyingly) define __cpp_concepts, even
though it doesn't support them, so we need to further check for
__COVERITY__ explicitly.
When using Userspace<T> there are certain syscalls where being able
to cast between types is needed. You should be able to easily cast
away the Userspace<T> wrapper, but it's perfectly safe to be able to
cast the internal type that is being wrapped.
This is a very cheesy patch and I don't like it, but as Qt Creator does
not grok C++20 concepts yet, this makes it possible to still use syntax
highlighting.
We'll remove this hack the moment it stops being a problem. Note that
it doesn't actually affect the build since we use GCC, not Clang.
It was a bit odd that you could create a Userspace<int> and that
Userspace<int>::ptr() returned an int instead of an int*.
Let's use C++20 concepts to only allow creating Userspace objects with
pointer types. :^)
Since we already have the type information in the Userspace template,
it was a bit silly to cast manually everywhere. Just add a sufficiently
scary-sounding getter for a typed pointer.
Thanks @alimpfard for pointing out that I was being silly with tossing
out the type.
In the future we may want to make this API non-public as well.
This will be used in the kernel to wrap pointers into userspace memory
without convenient direct access. The idea is to use the compiler to
enforce that we don't dereference userspace pointers.
