How to compile and use objc runtime from Apple source code?

Question

As we know, objc runtime is open source and can be downloaded from: http://www.opensource.apple.com/tarballs/objc4/

After loading the tarball, remove it. I open objc.xcodeprojwith xcode. However, when I create it, there are a lot of erros, for example, they cannot find headers. I looked at all the missing headers, downloaded them, put them in /tmp/objc.dst/usr/include. But with no luck, there are still mistakes.

I searched on the Internet, but I can find several documents or instructions about:

• how to compile apple objc executable from source code?
• After compilation, I should get libobjc.A.dylibhow to use it (as a replacement for the libobjc.A.dylib system)?

I really appreciate any help you can provide.

Answer 1

Compile without errors in accordance with 10.10.2 (14C1514), Xcode 6.2 (6C131e).

• You need the OSX 10.8 SDK, which you can get from the early Xcode install dmg or this repository https://github.com/phracker/MacOSX-SDKs (when downloading sdk from this repo, you may need to fix the soft links using this script http://blog.jeswang.org/blog/2014/10/26/fix-slash-soft-slash-links-slash-in-slash-an-slash-archived-slash-file/ , you may need to run a script twice for link recursion)

• Over 10.8 sdk to /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs

• https://github.com/Jeswang/objc4-532.2

• debug-objc

• .