[clang] [llvm] [Utils] add --update-tests flag to llvm-lit (PR #97369)

[Nicolai Hähnle via cfe-commits]

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@@ -0,0 +1,10 @@
+// RUN: %clang_cc1 -verify %s
+// RUN: diff %s %s.expected
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nhaehnle wrote:

The way I understand it, the update-verify-tests plugin in lit will overwrite this source file, which may end up overwriting this RUN line if there is a bug. Basically, there is a weird circularity here.

Therefore, it seems to me that the RUN lines for the `diff` against expected ought to be in the `lit-plugin.test` file instead.

https://github.com/llvm/llvm-project/pull/97369