I had gotten this set of error and could not figure out where the problems were:
I was trying to run Build in Xcode for iOS using libpd-ios.a but wonder why the architecture is i386 while the architecture in the setting is set to ARM 64 ARM6 and ARM7.

Undefined symbols for architecture i386:
"OBJC_CLASS$_PdBase", referenced from:
objc-class-ref in GTViewController.o
"OBJC_CLASS$_PdDispatcher", referenced from:
objc-class-ref in GTViewController.o
"_fiddle_tilde_setup", referenced from:
-[GTViewController viewDidLoad] in GTViewController.o
"OBJC_CLASS$_PdAudioController", referenced from:
objc-class-ref in GTAppDelegate.o
ld: symbol(s) not found for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)