Xcode - unidentified symbols for architecture archs in libpjmedia-codec-arm-apple-darwin9.a(opencore.o)

I really having a hard time to figure out the problem. i'm using PJSIP and also opencore-amr.

1. successfully compiled opencore-amr to arm64 (lipo -info told me)
2. successfully integrate opencore-amr (arm64) with PJSIP (arm64),configure it, make dep, make clean and make without any error.
3. when i try to compile it with XCode. it says

Undefined symbols for architecture arm64: "_Decoder_Interface_Decode", referenced from: _amr_codec_decode in libpjmedia-codec-arm-apple-darwin9.a(opencore_amr.o)

4. I did ar-t libpjmedia-codec-arm-apple-darwin9.a and the opencore.o inside the library is arm64.

I really have no clue to solve this. please help me, thanks

FYI : I've tried open core with pjsip for android, and no issue at all.

This is the linker error, you probably forgot to link some library. Go to Project settings -> Build phases -> Link Binary with Libraries section and review it. Try to google which framework contains the classes mentioned in error log and then add it to frameworks list.