- _LIBCPP_ENABLE_THREAD_SAFETY_ANNOTATIONS: This macro is used to enable -Wthread-safety annotations on libc++’s std::mutex and std::lock_guard.
- _LIBCPP_ENABLE_HARDENED_MODE to enable the hardened mode.
these have a slight runtime hit (like fortify-source), but help find
bugs early, by making programs crash on invariants that would corrupt
memory and lead to hard to debug crashes/bugs later.
these are mostly useless and redundant given the other flags. all they
do is spam more flags onto every invocation line- things don't "only"
pass cppflags for anything in the general case.
this is a good thing to have and we should reinstate it after 3.18,
however it requires fixing a million things, which is a bit too much for
a sudden release build.
i forgot the implications of this aside from fixing strerror_r and how
much work it was, so put this back after 3.18 branch.
jvoisin
ptrcnull
psykose
Natanael Copa