[clang] [clang][modules] Print library module manifest path. (PR #76451)

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,40 @@
+// Test that -print-library-module-manifest-path finds the correct file.
+
+// RUN: rm -rf %t
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MaskRay wrote:

You can remove `mkdir -p %t` and simplify this to `rm -rf %t && split-file %s %t && cd %t`. This does place 3 commands on one line, but is pretty common.

https://github.com/llvm/llvm-project/pull/76451