Since LIBCXX_ENABLE_FILESYSTEM now truly represents whether the
platform supports a filesystem (as opposed to whether the <filesystem>
library is provided), we can provide a few additional classes from
the <filesystem> library even when the platform does not have support
for a filesystem. For example, this allows performing path manipulations
using std::filesystem::path even on platforms where there is no actual
filesystem.
rdar://107061236
Differential Revision: https://reviews.llvm.org/D152382
Instead of writing something like `XFAIL: use_system_cxx_lib && target=...`
to XFAIL back-deployment tests, introduce named Lit features like
`availability-shared_mutex-missing` to represent those. This makes the
XFAIL annotations leaner, and solves the problem of XFAIL comments
potentially getting out of sync. This would also make it easier for
another vendor to add their own annotations to the test suite by simply
changing how the feature is defined for their OS releases, instead
of having to modify hundreds of tests to add repetitive annotations.
This doesn't touch *all* annotations -- only annotations that were widely
duplicated are given named features (e.g. when filesystem or shared_mutex
were introduced). I still think it probably doesn't make sense to have a
named feature for every single fix we make to the dylib.
This is in essence a revert of 2659663, but since then the test suite
has changed significantly. Back when I did 2659663, the configuration
files we have for the test suite right now were being bootstrapped and
it wasn't clear how to provide these features for back-deployment in
that context. Since then, we have a streamlined way of defining these
features in `features.py` and that doesn't impact the ability for a
configuration file to stay minimal.
The original motivation for this change was that I am about to propose
a change that would touch essentially all XFAIL annotations for back-deployment
in the test suite, and this greatly reduces the number of lines changed
by that upcoming change, in addition to making the test suite generally
better.
Differential Revision: https://reviews.llvm.org/D146359
Since those features are general properties of the environment, it makes
sense to use them from libc++abi too, and so the name libcpp-has-no-xxx
doesn't make sense.
Differential Revision: https://reviews.llvm.org/D126482
It turns out that D105040 broke `std::rel_ops`; we actually do need
both a one-template-parameter and a two-template-parameter version of
all the comparison operators, because if we have only the heterogeneous
two-parameter version, then `x > x` is ambiguous:
template<class T, class U> int f(S<T>, S<U>) { return 1; }
template<class T> int f(T, T) { return 2; } // rel_ops
S<int> s; f(s,s); // ambiguous between #1 and #2
Adding the one-template-parameter version fixes the ambiguity:
template<class T, class U> int f(S<T>, S<U>) { return 1; }
template<class T> int f(T, T) { return 2; } // rel_ops
template<class T> int f(S<T>, S<T>) { return 3; }
S<int> s; f(s,s); // #3 beats both #1 and #2
We have the same problem with `reverse_iterator` as with `__wrap_iter`.
But so do libstdc++ and Microsoft, so we're not going to worry about it.
Differential Revision: https://reviews.llvm.org/D105894
