Add lock annotations to the header files of our threading libraries.

This change extends all of the functions present in the <pthread.h> and
<threads.h> headers to have lock annotations. This will allow Clang to
warn about the following:

- Locking a function twice,
- Unlocking a function without a mutex being locked,
- Forgetting to unlock a mutex before returning,
- Destroying or reinitializing a mutex that is currenty locked,
- Using an unlocked mutex in combination with a condition variable.

Enabling these annotations already allowed me to catch a bug in one of
our userspace tools (r270749).

0 files changed, 0 insertions, 0 deletions