How Debuggers Work

on YouTube ↗20m

" summary

Covers how native debuggers on Linux map DWARF data to running code, read memory with ptrace PEEKDATA returning 64 bits, and set breakpoints either by writing 0xCC INT3 into code or using hardware watchpoints limited to four debug registers on x64. Shows how variable bytes are interpreted from DWARF type info, how a debugger fabricates calls via the platform ABI, and describes dynamic debugging that swaps optimized functions for unoptimized copies to restore stepping and visibility.

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" chapters (10)

1. 0:00Intro
2. 0:33What kind of debugger
3. 1:10Agenda
4. 1:43Debug Scenario Architecture
5. 3:33Memory Manipulation
6. 4:25Prace
7. 6:08Setting a breakpoint
8. 13:13Reading a variable
9. 15:53Calling a function
10. 17:51Debugging optimized code

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