llvm-project

4b9d7e16 - Reapply "[libc] Return errno from OFD failure paths in fcntl." (#166658) (#166846)

Reapply "[libc] Return errno from OFD failure paths in fcntl." (#166658) (#166846) The previous implementation in #166252 (rolled back in #166658) caused buildbot failures due to a bug in an added test. The modified `UseAfterClose` did not pass a `struct flock` value to `fcntl`: https://github.com/llvm/llvm-project/blob/2d5170594147b42a37698760d6e0194eec4f1390/libc/test/src/fcntl/fcntl_test.cpp#L175 Which ASAN caught and errored in the `fcntl` implementation when the unspecified argument was accessed: https://github.com/llvm/llvm-project/blob/c12cb2892c808af459eaa270b8738a2b375ecc9b/libc/src/__support/OSUtil/linux/fcntl.cpp#L59