Es sind zwei Patches für 10.4.2 verfügbar. Am einfachsten installiert man die über GetIt unter Kategorie Patches and Hotfixes.

Delphi 10.4.2 Compiler Patch fixt:
RSP-33425 Internal error AV0C793340(0C770000)-R00000018-0
RSP-33232 64bit Dll Debugging broken with runtime packages
RSP-32768 F2046 out of memory

RAD Studio 10.4.2 General Patch fixt:
RSP-33406 E2213 Falsches gepacktes Unit-Format: c:\program files (x86)\embarcadero\studio\21.0\lib\Win32\debug\rtl. dcp.System.SysUtils - Erwartete Version: 34.0, Windows Unicode(x86) Gefundene Version: 110.105, Unk(ARM)
RSP-33117 Critical: TRY..FINALLY block is broken for non-Windows platforms
RSP-32951 C++64: Debugger fatal error: debug kernel not responding. The debug process willl be terminated.
RSP-32939 Debugging of DLL with runtime packages is not possible at all
RSP-32043 Fatal linker error: Type index XXX is bad in module YYY when using clang compiler

Blog Artikel: RAD Studio 10.4.2 General Patch and Delphi Compiler Patch