[clang] [Driver][SYCL] Treat stdin as C++ when -fsycl is active (PR #204968)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,12 @@
+// UNSUPPORTED: system-windows
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AaronBallman wrote:

Why is this unsupported on Windows?

https://github.com/llvm/llvm-project/pull/204968