[all-commits] [llvm/llvm-project] 4e0275: [Driver] Mark -arch as TargetSpecific (#74365)

[Fangrui Song via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 4e0275a2c8f7f94cc1aacf4803fc827fad8f56d4
      https://github.com/llvm/llvm-project/commit/4e0275a2c8f7f94cc1aacf4803fc827fad8f56d4
  Author: Fangrui Song <i at maskray.me>
  Date:   2023-12-05 (Tue, 05 Dec 2023)

  Changed paths:
    M clang/include/clang/Driver/Options.td
    M clang/test/Driver/arc-exceptions.m
    M clang/test/Driver/arm-arch-darwin.c
    M clang/test/Frontend/darwin-eabi.c

  Log Message:
  -----------
  [Driver] Mark -arch as TargetSpecific (#74365)

`-arch` is a Darwin-specific option that is ignored for other targets
and not known by GCC.
```
% clang -arch arm64 -c a.c
clang: warning: argument unused during compilation: '-arch arm64' [-Wunused-command-line-argument]
```

We are utilizing TargetSpecific (from https://reviews.llvm.org/D151590)
to make more options lead to errors for unsupported targets.