Reviewing files that changed from the base of the PR and between 020ff30 and fc800b7.

• Lib/test/test_inspect/test_inspect.py is excluded by !Lib/**
• Lib/test/test_unittest/test_case.py is excluded by !Lib/**

• crates/vm/src/frame.rs
• crates/vm/src/vm/compile.rs

crates/vm/src/frame.rs (2)

1767-1772: LGTM: Precise frame equality check.

The pointer equality check correctly identifies exceptions whose traceback references this specific frame, ensuring only local reference cycles are broken while preserving tracebacks for exceptions from outer frames.

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1742-1777: Add context for the performance impact and clarify the frame pointer comparison safety.

The exception traceback cleanup logic is sound and properly safeguarded. Three important notes:

1. Frame pointer comparison: The core::ptr::eq::<Py<Frame>>(&*tb.frame, self.object) safely compares frame pointers—self.object is a valid current frame reference, and pointer equality comparison is safe in Rust.

2. Reference cycle prevention: The logic correctly breaks cycles by only clearing tracebacks where the exception's traceback top frame is THIS frame, preserving both the return value and active exception.

3. Performance consideration: This adds O(n) iteration on every function return where n = number of local variables. While most functions have few locals (minimal impact), functions with many locals or in hot paths may see measurable overhead. Consider documenting the expected performance characteristics or add a comment noting this is acceptable for correctness given RustPython's lack of tracing GC.

crates/vm/src/vm/compile.rs (1)

118-125: Correctly filters pseudo-paths when setting __file__.

The conditional check that skips __file__ for pseudo-paths like <string>, <stdin>, and <embedded> is correct and aligns with CPython's behavior. The simple string-based pattern !(source_path.starts_with('<') && source_path.ends_with('>')) effectively distinguishes synthetic sources from real file paths.