Xcode 4.6.3 Release was released on 12 Jun 2013 and requires macOS 10.7+.
It can be downloaded from https://download.developer.apple.com/Developer_Tools/xcode_4.6.3/xcode4630916281a.dmg.
Release notes are located at https://developer.apple.com/library/content/releasenotes/DeveloperTools/RN-Xcode/Chapters/Introduction.html#//apple_ref/doc/uid/TP40001051-CH1-SW600.
The SDKs it contains are:
- iOS 10B141
- macOS 11E52
- macOS 12D75
The compilers it contains are:
- clang 4.1 (Build 425.0.28)
- LLVM-GCC (Build 2336.11.00)