#10337: One-shot module loops have hard to understand messages -------------------------------------+------------------------------------- Reporter: ezyang | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.11 (Type checker) | Operating System: Unknown/Multiple Keywords: | Type of failure: None/Unknown Architecture: | Blocked By: Unknown/Multiple | Related Tickets: Test Case: | Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Consider these two modules: {{{ -- A.hs module A where -- B.hs module B where import A }}} `ghc --make B.hs` will compile this fine. Now edit `A.hs` to be circular: {{{ -- A.hs module A where import B }}} and attempt to one-shot compile it with `ghc -c A.hs`. You will now get an uninformative error message: {{{ A.hs:1:1: Circular imports: module `A' depends on itself }}} You can get a more informative message with `--make`: {{{ Module imports form a cycle: module `A' (A.hs) imports `B' (./B.hs) which imports `A' (A.hs) }}} We should either suggest users try again with `--make`, or try harder to give a useful message in one-shot mode. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10337 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler