Installation/compilation warnings involving `clang`, `cdhit`, `pansim`

[jananiravi]

Hello @thomasp85 Thanks for releasing this package. Looking forward to using it for microbial pangenome analysis! I encountered the following warnings while installing the package from GitHub.

Here's the gist of the warnings w/ the session info: https://gist.github.com/jananiravi/2dc460fa3c1fd6c57ec6e58cdeaa293e Here are further details on the environment used: https://gist.github.com/jananiravi/1136d342ee2b837eed3d6c6dccfb8f23 My R Make files: https://gist.github.com/jananiravi/1702e9bc1be61b4602a3e2aa285b3238

(FYI: I see the same warnings with R v3.5.3 as well, although the current attempt was with R v3.6.0)

Any suggestions on how to avoid these? thanks!