Implemented barrier synchronization for pthreads
- Uses condition variables internally for platform independence
(platform-specific work is handled by the condition variable
implementation)
- Does NOT currently handle barrierattr pshared, this is a goal for a
future patch
Fixes:
llvm-project/libc/test/integration/src/pthread/pthread_rwlock_test.cpp:59:29:
warning: missing field '__preference' initializer
[-Wmissing-field-initializers]
59 | pthread_rwlock_t rwlock = PTHREAD_RWLOCK_INITIALIZER;
| ^
Also, add a test that demonstrates the same issue for
PTHREAD_MUTEX_INITIALIZER, and fix that, too.
PTHREAD_ONCE_INIT does not have this issue and does have test coverage.
so that docgen can find our definitions.
Also eliminate the enums. POSIX is careful to call these "symbolic constants"
rather than specifically whether they are preprocessor macro defines or not.
Enums are useful to expressing mutual exclusion when the enum values are in
distinct enums which can improve type safety. Our enum values weren't using
that pattern though; they were all in one big anonymous enum.
Link:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/pthread.h.htmlFixes: #88997
