#12469: Memory fence on writes to MutVar/Array missing on ARM -------------------------------------+------------------------------------- Reporter: rrnewton | Owner: trommler Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: memory model Operating System: Unknown/Multiple | Architecture: Type of failure: Incorrect result | Unknown/Multiple at runtime | Test Case: Blocked By: | Blocking: 12537 Related Tickets: | Differential Rev(s): Phab:D2495 Wiki Page: | -------------------------------------+------------------------------------- Changes (by trommler): * owner: => trommler Comment: It seems there is a write barrier missing here in `StgCmmPrim.hs`: {{{ emit (setInfo addr (CmmLit (CmmLabel mkMAP_DIRTY_infoLabel))) -- the write barrier. We must write a byte into the mark table: -- bits8[a + header_size + StgMutArrPtrs_size(a) + x >> N] emit $ mkStore ( }}} I am going to add it an see what it is doing to #12537. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12469#comment:15 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler