Need card #200 · Relevance High · Status New

Debuggers that mislead developers

Updated 9/26/2026, 22:06:50

Problem

Multiple developers report that debuggers display incorrect or stale information about variables, control flow, and function calls, causing confusion, wasted time, and potential safety issues especially in low‑level or JIT environments.

Pain points

Questions to verify

Evidence

quote · @Anonymous
Reminds me of the time when visual studio would show one value of a variable, but print would show a different one. Never trusted VS again after that.
quote · @Anonymous
WinDbg has the same stale-cache trap on live Windows targets.
quote · @Anonymous
Once upon a time I had to figure out an issue where I forgot a `return` statement at the end of a non-`void` function, so the C++ compiler happily omitted both RETs for some reason and let the program go straight into illegal instructions. That was fun to debug (not fun, I practically had to single-step through the entire program) because every time this happened the debugger was incredibly confused about what the fuck was going on and nothing made any sense.
quote · @Anonymous
Debuggers can lie pretty often. Especially if you are just doing things with ASM. I had some issues with V8 debugging and the debugger just saying that a function got called which for sure wasn't. Even with the option that V8 should emit gdb info /

Disclaimer: this card is distilled by AI from community discussions as “pain point evidence”. It is a starting point for need analysis and validation, not a “validated market need”. AI has analytical limits; please open the original discussion above to manually verify before key decisions.