Viewing the code generated by @synthesize for getter/setter

Question

Is it possible to view the exact code generated by @synthesize?

Answer 1

Sure it is. Go to the .m file where you've @synthesized the property, then from the Build menu, choose "Show Assembly Code". The compiler conveniently puts in stuff like:

    .align  4, 0x90
"-[Foo setStr:]":
Leh_func_begin2:
Lfunc_begin2:
....

And

    .align  4, 0x90
"-[Foo answer]":
Leh_func_begin3:
Lfunc_begin3:
....

Oh, you wanted Objective-C code? Sorry, this is done by the compiler, and the compiler reads Objective-C, but writes in Assembly.

Answer 2

You can read the Clang compiler source to see the C++ code that generates the getter and setter methods:

http://llvm.org/svn/llvm-project/cfe/trunk/lib/CodeGen/CGObjC.cpp

It's pretty cryptic but that's the most accurate way of seeing the code generated.

You can also look at the objc_getProperty and objc_setProperty implementations in Apple's runtime implementation. While not literally the same as the code that is generated, this code is much easier to read and gives a clear indication of what a proper getter and setter should do.