coverage: Re-land "Enlarge empty spans during MIR instrumentation" by Zalathar · Pull Request #144663 · rust-lang/rust (original) (raw)

rust-timer added a commit that referenced this pull request

Jul 31, 2025

@rust-timer

Rollup merge of #144663 - Zalathar:empty-span, r=petrochenkov

coverage: Re-land "Enlarge empty spans during MIR instrumentation"

This allows us to assume that coverage spans will only be discarded during codegen in very unusual situations.


This seemingly-simple change has a rather messy history:

Since then, a number of related changes have landed that should make it reasonable to try again:

In particular, we have multiple fixes/mitigations, and a confirmed regression test for the original bug that is not triggered by re-landing the changes in this PR.