Duncan Coutts pushed to branch wip/dcoutts/issue-26717 at Glasgow Haskell Compiler / GHC Commits: 40f43b89 by Duncan Coutts at 2026-05-06T14:45:56+01:00 Add a changelog entry - - - - - 1 changed file: - + changelog.d/T26716 Changes: ===================================== changelog.d/T26716 ===================================== @@ -0,0 +1,15 @@ +section: rts +synopsis: Fix a use-after-free bug in the poll I/O manager +issues: #26716 #26717 +mrs: !15519 +description: { + Experimental work on ASAN support for GHC (MR !15168) revealed a + use-after-free bug when using the combination of the new poll I/O + manager with the compacting GC. The ultimate cause is that a TSO's + `block_info` (used by I/O managers and many other parts of the RTS) + is sometimes a GC pointer and sometimes not, but without a consistent + and easy-to-follow rule for when this is the case. The solution has + been to clean up and enforce that the TSO's `why_blocked` enumeration + is a proper tag for the `block_info`, and to use an encoding that + determines precisely when the `block_info` is a pointer or not. +} View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/40f43b8952e55d497b046491a0a97189... -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/40f43b8952e55d497b046491a0a97189... You're receiving this email because of your account on gitlab.haskell.org.