[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
+//
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MaskRay wrote:

Drop `^//$` lines. The conventional style doesn't add these markers for otherwise blank lines. Without them, we can navigate among the tests using vim-style `{` `}` .

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