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Make UInt panic on overflow if overflow_checks
is enabled
#408
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Is there a reason that using the |
As I said this requires me to depend on special clippy lints. But okay, this is your project, so feel free to close this issue if you want |
when writing consensus code, I would strongly recommend always using checked arithmetic, even with primitive number types, rather than panicking. Accidentally leaving reachable panics in consensus code can lead to network-wide DOS for now, closing this as |
Would it be possible to reassess this as I don't think it's the correct behaviour. I fully agree that people shouldn't be relying on behaviour like this to catch errors, but I was running into issues with overflows and had a hard time debugging the issue as the assumption was that the behaviour here would be the same as the standard rust types. I think the decision of the way to do things should not made here as it has already been decided by the rust team with the standard types. I would argue that replicating the default rust behaviour is far more important than trying to enforce good practice with a different behaviour in this library that nobody will know about unless they are hit by this case wile debugging and end up on this issue like I did. I think the above comment for using checked arithmetic is a very reasonable thing to say as an argument against the rust standard types behaviour, but here it's far more important to have consistent behaviour with those types and to panic in debug. |
For reference, the issue I had debugging was that I was debugging under the rust assumption that in debug mode, overflows will panic. It took a long time checking many other parts of the code before I realised that it was overflowing, and it was the different behaviour in this library that broke that assumption. |
Currently
UInt
wraps on overflow. Please, make it panic on overflow ifcfg(overflow_checks)
is enabled, i. e. exactly same thing rustc does with standard numbers. Here is why.First and foremost,
ruint
is used mainly for representing monetary values. Wrapping behavior is unnatural for monetary values. So,UInt
should panic on overflow. But still some users may want to skip checks for speed reasons. So, we should provide way to configure behavior. The most natural thing to do is to makeUInt
panic when standard numbers panic and wrap when standard types wrap. So, we should usecfg(overflow_checks)
.Of course, this is breaking change, so it should be done in 2.0.0.
I use
alloy
for managing my cryptocurrency, i. e. for transferring it around. Unnoticed overflows may cause loss of money, I absolutely don't want this.alloy
directly usesruint
'sUInt
. So, I plan to create my wrapper aroundU256
, which will panic on overflow. And I also will useclippy::arithmetic_side_effects
to make sure that I will not use arithmetic directly onruint
/alloy
'sU256
. But ideally this should be fixed inruint
itselfThe text was updated successfully, but these errors were encountered: