Hi all, I have created the analog to rust-gc crate library: [image] GitHub - redradist/ferris-gc: FerrisGC is a thread safe Garbage Collector... FerrisGC is a thread safe Garbage Collector implementation for Global (between threads) and Local (per thread) Garbage Collector - GitHub - r…

The link above explains that different pointers to the same trait object are not guaranteed to be equal because the compiler may generate multiple copies of the vtable. This is just an unfortunate fact of how trait objects are compiled currently. See my earlier comments for how to work around this…

What are you using for the hashmap key? It may be that the Hash and Eq implementations don't match up, or the key gets mutated while it is in the map. Both of these will break your map in weird and wonderful ways. (from the HashMap docs ) It is required that the keys implement the Eq and Hash …

[image] Michael-F-Bryan: What are you using for the hashmap key? It may be that the Hash and Eq implementations don't match up, or the key gets mutated while it is in the map. Both of these will break your map in weird and wonderful ways. (from the HashMap docs ) It is required that the keys i…

The key has type *const dyn Trace, which is a fat pointer (data pointer + vtable pointer). Unfortunately, in some circumstances, two different fat pointers to the same trait object can have different vtable pointers, and thus different hashes: https://github.com/rust-lang/rust/issues/46139 You cou…

[image] mbrubeck: The key has type *const dyn Trace, which is a fat pointer (data pointer + vtable pointer). Unfortunately, in some circumstances, two different fat pointers to the same trait object can have different vtable pointers, and thus different hashes: Consider warning when comparing w…

But ... I think this is exactly what I need that two different objects have different trait object pointers ... Maybe there are some issue with Hasher and PartialEq for trait object ?

If your objects all occupy disjoint locations in memory, then different objects will always have different pointers. The only problem is if you might have two objects occupying the same or overlapping locations. (For example, if one of your objects is a struct, and another object stored inline in …

[image] mbrubeck: If your objects all occupy disjoint locations in memory, then different objects will always have different pointers. The only problem is if you might have two objects occupying the same or overlapping locations. (For example, if one of your objects is a struct, and another ob…

How are you checking the key during iteration? If you are printing it out using dbg! or println! then you will only see half of the fat pointer, the "data" part. For example: let x: *const dyn Debug = &"hello"; dbg!(x); // prints "x = 0x000055a6d15c84c8" // For debugging purposes only; don't do t…

[image] mbrubeck: How are you checking the key during iteration? If you are printing it out using dbg! or println! then you will only see half of the fat pointer, the "data" part. For example: let x: *const dyn Debug = &"hello"; dbg!(x); // prints "x = 0x000055a6d15c84c8" // For debugging pur…

The interesting fact is that: let mut trs = self.trs.write().unwrap(); dbg!("tracer = {}", tracer); dbg!("trs.len = {}", trs.len()); for trc in (&*trs).into_iter() { dbg!("trc = {}", trc.0); if *trc.0 == tracer { dbg!("Key is found, trc = {}", trc.0); } else { dbg!("tracer{} != …

RwLock<HashMap> no entry found!

help

redradist May 11, 2020, 5:19pm 15

Okay, I got the idea ...

But will be it fixed later ?
... because it is very strange behavior ...

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RwLock<HashMap> no entry found!

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