Behind the Scenes: Debugging Kotlin/Wasm

on YouTube ↗25m

" summary

Kotlin compiles IR directly to Wasm binaries (no LLVM) and the toolchain relies on GC and reference types plus optional exception handling; debug UX comes from name and extended name sections and Source Map v3 with a generated sourceMappingURL custom section so browsers can map instructions back to Kotlin sources. Variable views use Chrome/Firefox custom formatters; an ignore list is used to hide intrinsics (now merged into V8). Outside the browser, toolchain emits DWARF (debug_info/debug_line) for lldb and aims to support Wasmtime and WAMR.

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" chapters (11)

1. 0:00Kotlin/Wasm debugging intro
2. 2:34In-browser debugging with DevTools
3. 6:50Enhancing debug info with name sections
4. 7:54Mapping instructions to source with Source Maps
5. 10:45Customizing variable views in debuggers
6. 14:16Improving debug experience with ignore lists
7. 15:44Exploring Source Maps scope proposal
8. 16:47Challenges with expression evaluation
9. 18:30Outside-browser debugging with LLDB
10. 20:23Generating DWARF debug info
11. 23:13Future work and collaboration

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