Zcoin implementation bug enabled attacker to create over 500K Zcoins

Post by MrDosu » Tue, Mar 07, 2017, 8:50 PM UTC

anjc wrote: post #151

MrDosu wrote: post #45

I always wonder how these "five conditions ANDed together in an if" make it past code review in general (i know thats not where the actual bug was). I don't care how brilliant a programmer you are, but mistakes in those are very difficult to grasp.

As convoluted as they can be, what alternatives are there other than nested conditions, which are equally convoluted? Surely if you need to logically compare five variable then you'll be doing it in some variation of 5 chained operations.

Post by IA21 » Wed, Mar 08, 2017, 2:08 AM UTC

zuzun wrote: post #100

yjgyhj wrote: post #71

The point I'm about to make in this comment is so old and has been said so many times that we all are tired of hearing it. But why do we use a language like C++ to implement something where we don't wish to have bugs? C++ is not memory-safe (no GC or whatever Rust does), it's not type safe (in the ML sense), it relies on writing to memory a lot (instead of having pure functions). Had this program been written in Ocam…

You are looking at a 1k LOC function in a 7k LOC file with a bug that can be easily spotted by -Wall and you think it's the fault of the programming language? The only thing irresponsible is putting your hard-earned money into the 100th Bitcoin fork maintained by some guy with an Anime avatar. Once you stop trusting the developers it essentially becomes an underhanded ... contest and no language wins.

Post by aaronmdjones » Wed, Mar 08, 2017, 9:34 AM UTC

pacaro wrote: post #172

Sanddancer wrote: post #135

Earlier quoted context omitted.

Yep. I'd add that if it's a warning you're absolutely certain of, use the warning control pragmas to suppress them, and document why the warning's suppressed. Keep the compiler output clean so you can see where you need to examine.

Yup. I'm a big fan of -Wall -Wextra -Werror If these options are set before you write any code, then these problems don't arise.

  -Weverything

Post by CyberDildonics » Wed, Mar 08, 2017, 1:59 PM UTC

aij wrote: post #201

CyberDildonics wrote: post #194

Earlier quoted context omitted.

Hello world in Rust is still 2.5MB if you statically compile all the libraries in since it doesn't strip unused functions. The tools and ecosystem are nowhere near what they are for C++

> Hello world in Rust is still 2.5MB if you statically compile all the libraries in Still? Since when? Last I checked it was 661kB for Rust vs 829kB for C, and that was quite a while ago. http://stackoverflow.com/a/29461455/2343847

Post by igouy » Wed, Mar 08, 2017, 6:25 PM UTC

igouy wrote: post #192

hvidgaard wrote: post #81

Earlier quoted context omitted.

Properly unmanaged code will probably always be faster than managed code. But the point still stands. Code in a managed language, identify the hot spots and inject highly performant unmanaged code there. There is no need to go full C++ for 99.999% of all projects.

Like this? http://benchmarksgame.alioth.debian.org/u64q/program.php?tes... How should /unsafe be set with .Net CORE csproj ?

    "buildOptions": {
        "allowUnsafe": true
    }

    
        
            true