“dynamic_cast From Scratch”
summary
Builds a complete, bug‑free reimplementation of dynamic_cast using the Itanium C++ ABI and a small set of nonportable helpers, exposes where compilers waste work (e.g. missed final optimizations), and replaces the library graph search with hand-crafted RTTI tables plus a tiny dispatch function. Tests use a Python fuzzer and end-to-end benchmarks; results show identical void* codegen and faster results for many real casts, with source and examples on GitHub.
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chapters (12)
- 0:00Introduction
- 0:26Polymorphism basics
- 4:21Multiple & virtual inheritance
- 7:03Object layout & v-tables
- 12:17RTTI and v-table data
- 19:24Visualizing class hierarchies
- 25:12Dynamic cast behavior
- 31:44Implementing casting
- 37:50Runtime graph algorithms
- 42:06Accessibility and finalization
- 52:24Performance benchmarks
- 56:04Q&A and conclusion
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