[llvm] [FileCheck] improve prefix validation (PR #92248)

[James Henderson via llvm-commits]

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@@ -2486,6 +2489,14 @@ static bool ValidatePrefixes(StringRef Kind, StringSet<> &UniquePrefixes,
              << "check and comment prefixes: '" << Prefix << "'\n";
       return false;
     }
+    for (StringRef Directive : Directives) {
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jh7370 wrote:

What's the motivation for this part of the change? Has it caused issues?

If we are doing this, a test should be added to the FileCheck test suite.

https://github.com/llvm/llvm-project/pull/92248