Developer reports
LLVM lit feature gate trace
Explain supplied REQUIRES, UNSUPPORTED and XFAIL literal-feature gates.
Your inputs
Start with an exampleYour result
Example resultHow it works
Evaluate case-sensitive literal features with !, &&, || and parentheses. The feature true is implicit; false is an ordinary feature name. All REQUIRES must pass, any matching UNSUPPORTED disables, and any matching XFAIL only marks expected failure if the test runs.
The captured Linux/asserts/target features satisfy both example requirements. Darwin is absent, so the supplied gates are enabled. Linux XFAIL changes a hypothetical pass/fail to XPASS/XFAIL; it does not skip the test.
Limits
Extracted arrays only: at most 10000 feature strings, 500 total expressions, 4096 characters per expression, depth 64, 50000 tokens, 500000 input characters and a 4 MiB report. Literal identifiers use ASCII letters, digits and -+=._; target triples match complete feature names. Python regex fragments, whole test files, comma splitting, continuations, config discovery, custom keywords and runner overrides are outside scope. Only exact * in XFAIL is a wildcard. Every supplied expression is validated. No host probing, RUN execution or actual test-status prediction.