Reduce the reproducer and establish expected behavior

Time: About 150 minutes: 45 reading, 75 lab, 20 testing, 10 notes.
Prerequisites: Day 22: Choose a small useful contribution

Toolchain: current-main build

Use build/bin/clang++ and build/bin/llvm-lit from your llvm-main checkout, not whichever clang++ is first on PATH. Reproduce upstream behavior on current main and record the commit SHA. Setup guide

Learn

Minimal examples and language-rule evidence.

Read Reading

Your llvm-project checkout + R17
The selected issue, nearby tests and the relevant C++ rule or Clang documentation · up to 45 min

Reading budgets cover selected sections, not whole chapters. Link to the book; this site does not reproduce it.

Build Build or investigate

Reduce the failing program, remove unrelated includes, and record compiler SHA, target, flags and observed behavior.
Explain why the expected behavior is correct; another compiler is supporting evidence, not the specification.
For a documentation task, preserve the exact failing documented workflow.

Done when

A minimal reproducer and a reasoned expected-versus-actual note.

Recall question

Which remaining line is necessary to trigger the problem?

Completion checks

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Notes

Saved only in this browser. Keep it short enough to finish in ten minutes; none of the prompts are required. All notes, export and import