Rust 1.98.1 has been released to fix a critical soundness bug from the previous version 1.98.0, which could lead to the compiler emitting null function pointers in trait-object vtables, causing safe code to crash. This issue was discovered by a developer while using the Rama HTTP proxy framework, where it resulted in segmentation faults during execution. The vtable generation bug is part of a pattern of similar issues that have caused problems in previous releases, where silently miscompiled code could lead to runtime failures without any compiler warnings. Users are strongly advised to update to version 1.98.1 immediately to avoid potential crashes in production environments
Rust 1.98.1 Released: Fixing Critical Vtable Miscompilation That Triggers Segfaults
The Rust 1.98.1 update is addressing a critical soundness bug in 1.98.0 where the compiler could emit null function pointers in trait-object vtables. The miscompilation causes safe code to crash with undefined behavior, a issue discovered by GlenDC while running the Rama HTTP proxy framework on aarch64-apple-darwin. This bug belongs to a recurring class of vtable generation issues in rustc, following related soundness holes in earlier 2026 releases involving boxed async services and impossible predicates. The Rust team shipped the fix just two weeks after the stable release, and users are advised to update immediately to prevent runtime failures in production.
