[llvm] [FileCheck] Create test to highlight the "more than 9 back-references" issue. (PR #173501)

[Thomas Symalla via llvm-commits]

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@@ -0,0 +1,8 @@
+; RUN: FileCheck -input-file %s %s
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tsymalla wrote:

I don't see it that way. The docs state:

Conversely, XFAIL actually runs the test but expects a failure output

And this is what is happening here.
In reality, we do not seem to have any test coverage for this case so I don't think we should waste time  on discussing whether XFAIL or not is appropriate here. It fits the case and the intend is to fix this issue, not to highlight there is an issue that is actually intended behavior.

https://github.com/llvm/llvm-project/pull/173501