Re: [GHC] #14346: 8.2.1 regression: heap corruption after safe foreign calls

#14346: 8.2.1 regression: heap corruption after safe foreign calls -------------------------------------+------------------------------------- Reporter: andrewchen | Owner: (none) Type: bug | Status: new Priority: highest | Milestone: 8.6.1 Component: Compiler | Version: 8.5 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: Runtime crash | Test Case: Blocked By: | Blocking: Related Tickets: #15260 | Differential Rev(s): Phab:D5020 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Ben Gamari ): In [changeset:"56590db07a776ce81eb89d4a4d86bd0f953fb44e/ghc" 56590db/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="56590db07a776ce81eb89d4a4d86bd0f953fb44e" base: Make Foreign.Marshal.Alloc.allocBytes[Aligned] NOINLINE As noted in #14346, touch# may be optimized away when the simplifier can see that the continuation passed to allocaBytes will not return. Marking CPS- style functions with NOINLINE ensures that the simplier can't draw any unsound conclusions. Ultimately the right solution here will be to do away with touch# and instead introduce a scoped primitive as is suggested in #14375. Note: This was present in 8.2 but was never merged to 8.4 in hopes that we would have #14375 implemented in time. This meant that the issue regressed again in 8.4. Thankfully we caught it in time to fix it for 8.6. (cherry picked from commit 404bf05ed3193e918875cd2f6c95ae0da5989be2) }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14346#comment:37 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler