[llvm] [FileCheck]: Fix diagnostic for trailing CHECK-NOT (PR #78412)

[Thomas Preud'homme via llvm-commits]

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@@ -0,0 +1,12 @@
+; RUN: rm %t && \
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RoboTux wrote:

That fails for me when the file does not already exists. If works if I add a -f

https://github.com/llvm/llvm-project/pull/78412