This aims to replace the different decorators we've had on each libc++
test with a single solution. Each libc++ will be assigned to the
"libc++" category and a single central piece of code will decide whether
we are actually able to run libc++ test in the given configuration by
enabling or disabling the category (while giving the user the
opportunity to override this).
I started this effort because I wanted to get libc++ tests running on
android, and none of the existing decorators worked for this use case:
- skipIfGcc - incorrect, we can build libc++ executables on android with gcc (in fact, after this, we can now do it on linux as well)
- lldbutil.skip_if_library_missing - this checks whether libc++.so is loaded in the proces, which fails in case of a statically linked libc++ (this makes copying executables to the remote target easier to manage).
To make this work I needed to split out the pseudo_barrier code from the
force-included file, as libc++'s atomic does not play well with gcc on
linux, and this made every test fail, even though we need the code only
in the threading tests.
So far, I am only annotating one of the tests with this category. If
this does not break anything, I'll proceed to update the rest.