This saved my day

export C_INCLUDE_PATH=/usr/lib/llvm-6.0/lib/clang/6.0.0/include"${C_INCLUDE_PATH+:}${C_INCLUDE_PATH-}"

Looks like that should be detected automatically by clang-sys though... What system are you on?

@emilio Ubuntu 10.x

@trsh thank you you comment saved me after hours trying to debug this!
@emilio btw this still happens to my during a docker build using debian buster trying to build bindings for rocksdb in the librocksdb-sys crate

Update: nvm it didn't really fix the problem :/
Update 2: omg I was missing the clang package, I wonder why it wasn't complaining about the missing binary...

(FWIW, comment edits don't arrive to my email notifications, so you were just lucky that I saw your mention :))

I think it's resolved now per your latest edits, but if it still happens when there's a usable clang / libclang in the system it should be filed upstream in https://github.com/kylemayes/clang-sys, which is what bindgen uses to find the library.

@emilio woops sorry :) Anyway, it is solved because I've installed the clang binary package, you think is still worth opening an issue on clang-sys? I'm a rust beginner so I'm not exactly sure what to do here but if it's something that's supposed to work maybe I should open one