[clang] [clang][Driver] Add a custom error option in multilib.yaml. (PR #105684)

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,63 @@
+# REQUIRES: shell
+# UNSUPPORTED: system-windows
+
+# RUN: rm -rf %T/baremetal_multilib
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MaskRay wrote:

do not use `%T`

https://llvm.org/docs/CommandGuide/lit.html#substitutions

just use `rm -rf %t && mkdir %t` for what you do with `%T/baremetal_multilib` ?

https://github.com/llvm/llvm-project/pull/105684