[clang] [Clang][Driver] Add option to provide path for multilib's YAML config file (PR #109640)

[Oliver Stannard via cfe-commits]

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@@ -1,79 +1,79 @@
-// RUN: %clang -print-multi-flags-experimental --target=aarch64-linux -fc++-abi=itanium -fsanitize=address | FileCheck --check-prefix=CHECK-LINUX %s
+// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-linux -fc++-abi=itanium -fsanitize=address | FileCheck --check-prefix=CHECK-LINUX %s
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ostannard wrote:

This is needed since #105684 allows reporting errors from multilib.yaml for option combination there is no library for. This causes the tests to fail when building clang as part of https://github.com/ARM-software/LLVM-embedded-toolchain-for-Arm, which has a multilib.yaml which uses that feature. Adding the option here makes the tests independent of other parts of the toolchain it is built into.

https://github.com/llvm/llvm-project/pull/109640