The kernel that ships with the new Ubuntu 22.04 CI image seems to have a
PIE slide that is bigger than the sanitizer runtimes can handle.
It makes ASan fail with thousands of "AddressSanitizer:DEADLYSIGNAL"
warnings, and MSan error with complaints about memory accesses outside
known ranges. Disabling address space layout randomization fixes both.
This commit also fixes a small bug in the platform_output test where
the cgroups v1 logic did not handle the "unlimited quota" special case
properly. Ubuntu 20.04 still uses cgroups v1.
Fixes a detected error: incompatible pointer to integer conversion
passing 'uv_os_fd_t' (aka 'void *') to parameter of type 'SOCKET' (aka
'unsigned long long').
Use upstream llvm to work-around broken VS2022 clang unable to link.
- unpoison results from linux system call wrappers
- unpoison results from stat/fstat/lstat to pacify clang 14
(fixed in later versions)
- add MSAN build option
- turn on MSAN CI build
Previously they were just being run incorrectly, but nothing wrong with
the test itself. We were also interpreting an ASAN failure as TEST_SKIP,
so test failures would not actually be reported as CI failures.