Xcode 4.6 Release was released on 28 Jan 2013 and requires macOS 10.7+.
It can be downloaded from https://download.developer.apple.com/Developer_Tools/xcode_4.6/xcode460417218a.dmg.
Release notes are located at https://download.developer.apple.com/Developer_Tools/xcode_4.6/release_notes_xcode46gm.pdf.
The SDKs it contains are:
- iOS 10B141
- macOS 11E52
- macOS 12D75
The compilers it contains are:
- clang 4.1 (Build 425.0.24)
- LLVM-GCC (Build 2336.11.00)