Xcode 12.0 Beta 5 was released on 18 Aug 2020 and requires macOS 10.15.4+.
It can be downloaded from https://download.developer.apple.com/Developer_Tools/Xcode_12_beta_5/Xcode_12_beta_5.xip.
Release notes are located at https://developer.apple.com/documentation/xcode-release-notes/xcode-12-beta-release-notes.
The SDKs it contains are:
- iOS 14.0 (Build 18A5351d)
- macOS 11.0 (Build 20A5354g)
- tvOS 14.0 (Build 18J5364d)
- watchOS 7.0 (Build 18R5361c)
The compilers it contains are:
- clang 12.0.0 (Build 1200.0.31.1)
- swift 5.3 (Build 1200.0.28.1)