XcodeNueve 🛠 9️⃣

A hack allowing the use of Xcode 9's toolchain on macOS Catalina, Big Sur, Monterey, Ventura, Sonoma, and Sequoia.

Why?

Xcode 9.4.1 and the macOS 10.13 SDK are the last versions capable of building 32-bit Intel (i386) binaries.

Due to internal frameworks that reference private AppKit instance variables (removed in macOS Catalina), Xcode 9 and its included toolchain fail to run on any macOS version past Mojave.

For projects which need to build i386 binaries to support macOS 10.14 and earlier (like Wine), this requires keeping around a 10.14 build machine, which is undesirable for a number of reasons (no more security updates, requires older hardware, can't also run latest Xcode, etc.)

Xcode 9 also may be useful for building old Swift projects.

What doesn't work?

Xcode.app itself does open, but crashes when trying to open a project (I think trying to access more private AppKit variables). This may be fixable, but isn't a priority for me.

Tell me how!

1. Download Xcode 9.4.1 from Apple Developer and extract it. I recommend renaming it to Xcode9.app and moving to /Applications.
2. Create a code signing signature (instructions courtesy of the XVim project):
   1. Open Keychain Access.app and select login in the left pane.
   2. In the menu bar, select Keychain Access -> Certificate Assistant -> Create a Certificate...
   3. For the Name I recommend "XcodeSigner", for Identity Type select "Self Signed Root", and for Certificate Type choose "Code Signing". Then click "Create", and continue through the warning.
   4. You should now have a self-signed code signing certificate in the "login" keychain.
3. On macOS Ventura and later, you will need to give Terminal.app "App Management" permissions in the Privacy & Security pane of System Settings. This permission can be removed after the script is successfully run.
4. Run the script from this repository and follow the prompts:
   /bin/sh -c "$(curl -fsSL https://raw.githubusercontent.com/mrpippy/XcodeNueve/master/XcodeNueve.sh)"

How do I use it?

• You'll need to set DEVELOPER_DIR=/Applications/Xcode9.app and SDKROOT=/Applications/Xcode9.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk, then run clang/gcc/xcrun/xcodebuild/whatever.
• The env command can be used to run this as a single command, like env DEVELOPER_DIR=/Applications/Xcode9.app SDKROOT=/Applications/Xcode9.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk clang -arch i386 ...
• Also, on Apple Silicon, you will need to explicitly run the command emulated under Rosetta, using arch -x86_64. I usually find it easier to just run the entire shell emulated: arch -x86_64 zsh.
• Building i386 binaries is considered cross-compiling, and may need additional options passed to a configure script/build system.
• For example, here's a typical invocation of configure on Apple Silicon:
  arch -x86_64 ./configure --host=i386-apple-darwin CC="env DEVELOPER_DIR=/Applications/Xcode9.app SDKROOT=/Applications/Xcode9.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk clang -arch i386"

Details

Here's the error you get when trying to run unmodified Xcode 9 (either the IDE itself or its command-line tools) under macOS Catalina and later:

% DEVELOPER_DIR=/Applications/Xcode9.app xcrun clang -v
dyld[83886]: Symbol not found: _OBJC_IVAR_$_NSFont._fFlags
  Referenced from: /Applications/Xcode9.app/Contents/SharedFrameworks/DVTKit.framework/Versions/A/DVTKit
  Expected in: /System/Library/Frameworks/AppKit.framework/Versions/C/AppKit

Who's reponsible for this?

Brendan Shanks
CodeWeavers