Flaky test RegexMatchTests.Match_TestThatTimeoutHappens(engine: SourceGenerated) #128201

Build Information

Build: https://dev.azure.com/dnceng-public/cbb18261-c48f-4abb-8651-8cdcb5474649/_build/results?buildId=1420477
Build error leg or test failing: System.Text.RegularExpressions.Tests.RegexMatchTests.Match_TestThatTimeoutHappens
Pull request: #128072

Error Message

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Fill the error message using step by step known issues guidance.

{
  "ErrorMessage": "System.Text.RegularExpressions.Tests.RegexMatchTests.Match_TestThatTimeoutHappens(engine: SourceGenerated) [FAIL]",
  "BuildRetry": true,
  "ExcludeConsoleLog": false
}

Previous issues about this test: #117111, #106096, #88418

    System.Text.RegularExpressions.Tests.RegexMatchTests.Match_TestThatTimeoutHappens(engine: SourceGenerated) [FAIL]
      Assert.Throws() Failure: No exception was thrown
      Expected: typeof(System.Text.RegularExpressions.RegexMatchTimeoutException)
      Stack Trace:
        /_/src/libraries/System.Text.RegularExpressions/tests/FunctionalTests/Regex.Match.Tests.cs(1600,0): at System.Text.RegularExpressions.Tests.RegexMatchTests.Match_TestThatTimeoutHappens(RegexEngine engine)
        --- End of stack trace from previous location ---
        --- End of stack trace from previous location ---

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1420477
Error message validated: [System.Text.RegularExpressions.Tests.RegexMatchTests.Match_TestThatTimeoutHappens(engine: SourceGenerated) [FAIL]]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 5/14/2026 3:03:26 PM UTC

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