Debug the frontend

Time: About 150 minutes: 30 reading, 90 lab, 20 testing, 10 notes.
Prerequisites: Day 18: Study one C++ semantic rule

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

Breakpoints, call stacks and a small reproducer.

Read Reading

R11 · Hacking on Clang
Debugging guidance · 15 min
Your learning notes
Review your day 18 source map · 15 min

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

Build Build or investigate

Using a build with debug symbols, stop in the checking function for a minimal example.
Inspect the relevant expression or type and record the call stack.
If symbols or memory block debugging, trace the same path manually and schedule a narrow debug build.

Done when

A debugger transcript or an explicit manual trace with the unresolved debugging limitation recorded.

Recall question

What extra information did the stack reveal beyond a text search?

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