# Valgrind

29 Hacker News commenters recommended Valgrind and 8 criticized it, November 2025 to November 2026. It was recommended in 13 of 13 months. It meets the Hacker Approved badge rule.

**Verdict:** Free tool that finds memory errors and leaks in native code, recommended as a routine check. Caveats: it is slow and sometimes reports false positives.

## Why people recommend it

- Catches memory errors and leaks (4 comments): "Leaks are trapped with tooling, and all you need is one dev in the team to be diligant to run valgrind" ([source](https://news.ycombinator.com/item?id=46931707)) "Tools like valgrind can be user to validate that you won't have any memory errors" ([source](https://news.ycombinator.com/item?id=46031409)) "use ASAN or Valgrind then leak detection is not difficult" ([source](https://news.ycombinator.com/item?id=46524907))
- Routine check alongside tests (5 comments): "I use valgrind or the sanitizers quite heavily to save myself from them" ([source](https://news.ycombinator.com/item?id=46435806)) "it's really worth adding all of them to a project if you can" ([source](https://news.ycombinator.com/item?id=46468358)) "a mandatory test pass running with UBSan/ASan/Valgrind" ([source](https://news.ycombinator.com/item?id=50201093))
- Underused and under-appreciated (3 comments): "Valgrind is a friend a lot of people haven't heard of for c/c++." ([source](https://news.ycombinator.com/item?id=50330427)) "even good old Valgrind is under-appreciated and under-used" ([source](https://news.ycombinator.com/item?id=46169166)) "take advantage of all the older tools like valgrind" ([source](https://news.ycombinator.com/item?id=48147940))
- Saves headaches, useful starting point (3 comments): "it helps immensely as a starting point same as valgrind helped in the past" ([source](https://news.ycombinator.com/item?id=46228351)) "saves a lot of headaches down the line" ([source](https://news.ycombinator.com/item?id=45782177)) "Valgrind and similar tools also help." ([source](https://news.ycombinator.com/item?id=49673911))

## What people warn about

- Slow, too slow for realtime (3 comments): "For realtime applications, Valgrind and friends are pretty much a non-starter." ([source](https://news.ycombinator.com/item?id=46640202)) "Valgrind is dramatically slower." ([source](https://news.ycombinator.com/item?id=49042277)) "Valgrind can be pretty rough!" ([source](https://news.ycombinator.com/item?id=47998805))
- False positives and buggy behavior (3 comments): "valgrind is super buggy and we spend quite a bunch of time working around valgrind false positives" ([source](https://news.ycombinator.com/item?id=45788904)) "valgrind not handling a valid optimization correclty" ([source](https://news.ycombinator.com/item?id=49990859)) "which is a bit too strict with uninitialized values" ([source](https://news.ycombinator.com/item?id=49979671))
- Misses some bugs and AVX512 instructions (2 comments): "Valgrind and asan will allow a buggy access (like an OOB) to succeed if the resulting address is valid at all" ([source](https://news.ycombinator.com/item?id=49294105)) "the lack of Valgrind support for many of the AVX512 instructions frustrates me almost daily" ([source](https://news.ycombinator.com/item?id=47238156))

## Alternatives hackers recommend

- [Miri](https://hackerapproved.com/p/miri.md): 26 recommend
- [AddressSanitizer](https://hackerapproved.com/p/addresssanitizer.md): 21 recommend
- [UndefinedBehaviorSanitizer](https://hackerapproved.com/p/undefinedbehaviorsanitizer.md): 12 recommend
- [Go race detector](https://hackerapproved.com/p/go-race-detector.md): 5 recommend
- [ThreadSanitizer](https://hackerapproved.com/p/threadsanitizer.md): 5 recommend

## Cite as

Hacker Approved, "Valgrind", https://hackerapproved.com/p/valgrind/ (counts from 1,795,640 Hacker News comments, November 2025 to November 2026).