#14998: Sort out the strictness mess for exceptions -------------------------------------+------------------------------------- Reporter: simonpj | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.4.3 Component: Compiler | Version: 8.2.2 Resolution: | Keywords: Exceptions Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by sgraf): There's no binary difference in `dump-cmm` for the hello world example (as expected) and there is no binary difference in the object files generated for GHC.IO.Handle.Text either, after `strip`ping. The only difference in GHC.IO.Handle.Internals seems to be in `do_operation` (no wonder, that was the only place Core differed). Here's the [https://www.diffchecker.com/w0h8gImt diff]. You can see that HEAD on the right somehow can jump to cbPP directly, whereas the patched version on the left needs to allocate a closure for actually calling the `act`ion (which I presume got ripped out into the `sat_entry` at the top). I'm not proficient enough with Stg/Cmm to tell why the single bang leads to better code, while the diff in Core is boring. Maybe a suprise hides in the way `catch#` is lowered? So, what should a Note look like that explains Phab:D4574? Just 'plugging a space leak'? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14998#comment:15 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler