Ocaml doesn't compile to C. Sometimes having translated C source is major gain.

I'm not Ocaml implementation expert, but I suppose Ocaml exception handling and garbage collector could be tricky to aware about when one extend or embed Ocaml.

To be honestly, my fellow did Ocaml embedding once. He made able to load natively-compiled plugins written in Ocaml into C based software. And it worked. I didn't dig into details, though. There was at least one bug regarding garbage collection (and it happens that I fixed it).