[clang] [Driver] Add the --gcc-triple option (PR #73214)

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,8 @@
+// UNSUPPORTED: system-windows
+//
+// RUN: %clang --target=x86_64-redhat-linux-gnu \
+// RUN: --sysroot=%S/Inputs/fedora_39_tree --gcc-triple=x86_64-redhat-linux -v 2>&1 | \
+// RUN: FileCheck %s
+//
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MaskRay wrote:

Add another test when `--gcc-triple=` specifies a triple where the associated path does not exist.

https://github.com/llvm/llvm-project/pull/73214