fix-codegen

name	fix-codegen
description	Fix a codegen bug in the TML compiler. Use when the user says "fix codegen", "corrige codegen", "codegen bug", or when a test fails due to incorrect LLVM IR generation.
user-invocable	true
argument-hint	<description of the bug or failing test>

Delegation: Use the Agent tool to dispatch a codegen-debugger agent with model: opus for this task.

Codegen Bug Fix Workflow

1. Reproduce

If a test file is given, run it:

• Use mcp__tml__test with path, verbose: true, no_cache: true

If a description is given, write a minimal .tml reproducer in .sandbox/.

2. Emit IR

Use mcp__tml__emit-ir on the failing file to see the generated LLVM IR.

3. Trace the Bug

Identify which codegen phase produces the bad IR:

• Search compiler/src/codegen/ for the relevant emission code
• Trace the value through: Source → HIR → MIR → LLVM IR
• Compare with Rust's IR for the equivalent code

4. Fix

Edit the compiler C++ source to fix the codegen.

5. Verify

1. Rebuild: /build
2. Re-run the failing test
3. Run affected suites: /verify
4. Emit IR again to confirm the fix

IMPORTANT

• Follow CLAUDE.md Rust-as-Reference methodology
• NEVER simplify tests — fix the compiler
• Update memory with the fix details for future reference