ARMv6, ARMv7, armv7s in iOS

ARMv6, ARMv7, armv7s is the ARM CPU instruction set, in principle is backward-compatible, such as: IPHONE4SCPU support ARMV7, but it will be compatible with ARMV6, but the use of ARMV6 instructions may not be able to fully exploit its characteristics. IPHONE5CPU supports armv7s, and it is also compatible with ARMV7.

If you refer to a third-party library, you did not have a problem compiling iphone4s, but after switching to iphone5, you are prompted:

Undefined Symbols for Architecture armv7s:
"_objc_class_$_amapview", referenced from:
Objc-class-ref in Libmamapkit.a (MAMAPVIEW.O)
Ld:symbol (s) not found for architecture armv7s

The general meaning is: XX class referencing from xx.a Static library does not support armv7s directive

The reason is: you refer to the static library does not support armv7s, then you want to successfully compile, either notify the development changes, wait for support after the test, or in Target's build settings valid architectures will armv7s first temporarily removed, Compile to succeed. (After waiting for support, add it again)