At Oxide, we sell cloud computers that run on Helios, a distribution of illumos, a Unix-based OS. Recently, I encountered a segmentation fault in the Rust compiler and used powerful debugging tools provided by illumos to track it down. During a “Rust @ Oxide” meetup, my colleagues and I turned this issue into a debugging session. The crash occurred during the bootstrap process of the Rust compiler, a self-hosting compiler, causing concern. Through examining core files with mdb, we found the cause of the crash to be related to memory permissions, leading to a theory about the stack space exhaustion.
https://sunshowers.io/posts/rustc-segfault-illumos/