[Bug]: vast-front with -cc1 fails to report unknown argument

[Jezurko]

VAST version

$ vast-front --version clang version 18.1.6 (git@github.com:llvm/llvm-project.git 1118c2e05e67a36ed8ca250524525cdb66a55256) Target: x86_64-unknown-linux-gnu Thread model: posix InstalledDir: /home/jezko/src/vast/builds/default/tools/vast-front/Debug

LLVM version

18.1.6

Operating system

Linux Solus

Description

When running vast-front -cc1 with an invalid option, it fails to report a problem and just silently ends with non-zero return code.

Steps to Reproduce

Run e.g. vast-front -cc1 -m16 test.c and clang -cc1 -m16 test.c for comparison. (-m16 can be replace by any random string that is not a valid option)