#10245: panic in new integer switch logic with "out-of-range" literals -------------------------------------+------------------------------------- Reporter: rwbarton | Owner: AndreasK Type: bug | Status: closed Priority: normal | Milestone: 8.2.1 Component: Compiler | Version: 7.11 (CodeGen) | Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: x86_64 Type of failure: Incorrect result | (amd64) at runtime | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4218 Wiki Page: | -------------------------------------+------------------------------------- Changes (by AndreasK): * status: patch => closed * resolution: => fixed Comment: Replying to [comment:15 AndreasK]:
In MatchLit [https://ghc.haskell.org/trac/ghc/browser/ghc/compiler/deSugar/MatchLit.hs#L7... dsLit] doesn't use the `mkMachInt` functions resulting in potentially faulty code.
`y = I# 0x8000000000000000# :: Int` compiles without warning with -Wall for example.
Fixing this would incur a overhead when compiling Code which generates Prim Literals. As these use the same code Path as user specified Literals we can't skip the checks on these even when we know these will not be out of bounds. Closing this after a discussion on IRC and it's not deemed a big enough issue to warrant the overhead. (wontfix as to not confuse this issue with the original one) -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10245#comment:18 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler