Xcode 3.2.5 Release was released on 18 Nov 2010 and requires macOS 10.6.4+.
It can be downloaded from https://download.developer.apple.com/ios/ios_sdk_4.2__final/xcode_3.2.5_and_ios_sdk_4.2_final.dmg.
Release notes are located at https://download.developer.apple.com/ios/ios_sdk_4.2__final/readme_xcode_3.2.5_and_ios_4.2.pdf.
The SDKs it contains are:
- iOS 4.2
The compilers it contains are:
- clang 1.6 (Build 70)
- LLVM-GCC (Build 2333.4)
- GCC 4.0 (Build 5494)
- GCC 4.2 (Build 5664)