Ensure that inliner inserts lifetime markers if they have been emitted during
codegen. Otherwise if allocas from inlined functions are merged together,
lifetime markers from one function might invalidate load & stores performed
by the other one.
Although `stack_overflow::init` runs very early in the process, even
before `main`, there may already be signal handlers installed for things
like the address sanitizer. In that case, just leave it alone, and don't
bother trying to allocate our own signal stacks either.
Compile address sanitizer test with debuginfo
This makes error-pattern to match regardless of current
configuration of `rust.debuginfo-level-tests` in `config.toml`.
Additionally verify that the current implementation of LLVM version
check (which uses lexicographic ordering) is good enough to exclude
versions before LLVM 9, where the new LLVM pass manager is unsupported.