Xcode (Universal) 12.0 Beta 2 was released on 7 Jul 2020 and requires macOS 10.15.4+.
It can be downloaded from https://download.developer.apple.com/Developer_Tools/Xcode_12_for_macOS_Universal_Apps_beta_2/Xcode_12_for_macOS_Universal_Apps_beta_2.xip.
Release notes are located at https://developer.apple.com/documentation/xcode-release-notes/xcode-12-for-macos-universal-apps-beta-release-notes.
The SDKs it contains are:
- iOS 14.0 (Build 18A5319g)
- macOS 11.0 (Build 20A5299v)
The compilers it contains are:
- clang 12.0.0 (Build 1200.0.22.41)
- swift 5.3 (Build 1200.0.16.15)