No template named 'unary_function' in namespace 'std'; did you mean '__unary_function'?

Issue

Just upgraded my Xcode to 15.0, and suddenly it started giving me the following error in RCT_Folly

No template named 'unary_function' in namespace 'std'; did you mean '__unary_function'?

this is the line where it fails:

struct hash_base : std::unary_function<T, std::size_t> {};

I tried removing cached data and derived data & cleaning build. Tried removing pods and node_modules as well. But nothing has helped.

Solution

In my case, I followed Xcode's suggestion after the build failed. I simply clicked on 'Fix,' and everything is working fine now.

I hope it will be fixed in the next updates.

Answered By - Alaa Kanaan