[llvm-dev] Asan in nightlies?

[William Cummings via llvm-dev]

I'm running debian jessie and added the nightly repos and installed
clang-3.8. When trying to build with -fsanitize=address clang can't find
an asan lib: 

/usr/bin/ld: cannot find
/usr/lib/llvm-3.8/bin/../lib/clang/3.8.0/lib/linux/libclang_rt.asan-x86_64.a:
No such file or directory

The apt page says the packages include compiler-rt which I thought
included asan. Am I missing a package?

Cheers,
Will