/usr/lib/ocaml/llvm-3.0/libLLVMX86Info.a is in libllvm-3.0-ocaml-dev 3.0-4ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ocaml/llvm-3.0/../../llvm-3.0/lib/libLLVMX86Info.a
/usr/lib/ocaml/llvm-3.0/../../llvm-3.0/lib/libLLVMX86Info.a