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Joined 1 year ago
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Cake day: July 13th, 2023

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  • Mem stomps are the worst. At least nowadays we have address sanitizer to find em. We recently had one where the same 4 byte pattern was being written randomly in different places in memory, would happen all over the place. Always the same 4 byte pattern, just different places. Eventually, it would write to a spot that was being used and cause a crash. Different callstacks almost every time, but the same memory footprint wherever the crash happened. An array size, a memory address, a string mangled, etc. Eventually we got our ASan build working after about a month of trying to track it down, digging through callstacks and core dumps. We found that it was a dangling pointer in our AI system, when an AI was removed, there was a situation where the pointer wouldn’t always be cleaned up, then later when another AI was removed, a boolean and an enum were written to the address of the dangling pointer, always the same format/value. which had haunted us for so long.









  • Some astronomers are looking at JWST data and claiming they are seeing galaxies with red shifts in the range of 11-20, which if accurate, correspond to ages older than we’d expect to see galaxies of such size formed. Other astronomers disagree, and believe that the results aren’t so clear. This the “hubble tension” or “crisis in cosmology” maybe still live on.

    It is exciting, either we get more data to confirm our current understanding or we need to discover be physics and form new theories that align with the data. Either way is great, imo.