Use of external C++ headers in Objective-C

Question

In my iOS project I need to use an external library written in C++. The C++ header files are all in one directory.

I\'ve added these C++ headers to my Xcode project

Answer 1

In Xcode 9, I need to add header files path to the Header Search Paths build setting, not User Header Search Paths.

Xcode will append User Header Search Paths to compile command as -iquote options, but append Header Search Paths as -I options. That's the key difference.