this post was submitted on 08 Jun 2024
1040 points (98.5% liked)

Programmer Humor

18255 readers
24 users here now

Welcome to Programmer Humor!

This is a place where you can post jokes, memes, humor, etc. related to programming!

For sharing awful code theres also Programming Horror.

Rules

founded 1 year ago
MODERATORS
 
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 17 points 3 weeks ago (2 children)

Good Afternoon Sir, have you heard about our lord and savior pthreads?

[–] [email protected] 27 points 3 weeks ago* (last edited 3 weeks ago) (3 children)

I'm not saying you can't do multi-threading or concurrency in C++. The problem is that it's far too easy to get data races or deadlocks by making subtle syntactical mistakes that the compiler doesn't catch. pthreads does nothing to help with that.

If you don't need to share any data across threads then sure, everything is easy, but I've never seen such a simple use case in my entire professional career.

All these people talking about "C++ is easy, just don't use pointers!" must be writing the easiest applications of all time and also producing code that's so inefficient they'd probably get performance gains by switching to Python.

[–] [email protected] 7 points 3 weeks ago (1 children)

That's the problem of most general-use languages out there, including "safe" ones like Java or Go. They all require manual synchronization for shared mutable state.

[–] [email protected] 20 points 3 weeks ago* (last edited 3 weeks ago) (1 children)

There's a difference between "You have to decide when to synchronize your state" and "If you make any very small mistake that appears to be perfectly fine in the absence of extremely rigorous scrutiny then this code block will cause a crash or some other incomprehensible undefined behavior 1/10000 times that it gets run, leaving you with no indication of what went wrong or where the problem is."

[–] [email protected] 4 points 3 weeks ago

that's so inefficient they'd probably get performance gains by switching to Python.

Damn, this goes hard for no reason.

[–] [email protected] 1 points 3 weeks ago (1 children)

Well, threadsanitizer catches them in runtime. Not sure about GCC static analyser and other SA tools.

[–] [email protected] 3 points 3 weeks ago* (last edited 3 weeks ago) (1 children)

I use thread sanitizer and address sanitizer in my CI, and they have certainly helped in some cases, but they don't catch everything. In fact it's the cases that they miss which are by far the most subtle instances of undefined behavior of all.

They also slow down execution so severely that I can't use them when trying to recreate issues that occur in production.

[–] [email protected] 1 points 3 weeks ago

They caught lock inversion, that helped to fix obscure hangs, that I couldn't reproduce on my machine, but were constantly happening on machine with more cores.

[–] [email protected] 1 points 3 weeks ago (1 children)

Wasn't biggest part of pthreads added in C11/C++11?

[–] [email protected] 3 points 3 weeks ago

So... I'm old. All my time working in C++ was pre-C++11