The Lost Atomic Update on Loongson CPU
What happened
In February 2026, Wang Miao ran into something strange while packaging normaliz for Debian on a LoongArch server: the math software's built-in test kept timing out, stuck in an infinite loop that it could not escape. Following the code, the problem pointed to a very ordinary operation: OpenMP's #pragma omp atomic accumulating into a shared variable. The loop's exit condition required the accumulated value to equal a…
Summary assembled by rule from the sources below
Why it's spreading
Timeline
- First appeared on Hacker NewsHacker News
- Discussion started on LobstersLobsters