#14522: GHC recompilation checker doesn't take account of deprecated pragmas -------------------------------------+------------------------------------- Reporter: NeilMitchell | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Incorrect Unknown/Multiple | error/warning at compile-time Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Given the sources: {{{#!hs -- A.hs -------------------- module A -- {-# DEPRECATED "bad" #-} where a = 1 }}} {{{#!hs -- B.hs -------------------- module B where import A }}} I get the interactions: {{{ $ ghc B [1 of 2] Compiling A ( A.hs, A.o ) [2 of 2] Compiling B ( B.hs, B.o ) $ manually edit A.hs to uncomment the deprecated line $ ghc B [1 of 2] Compiling A ( A.hs, A.o ) $ touch B.hs $ ghc B [2 of 2] Compiling B ( B.hs, B.o ) B.hs:2:1: warning: [-Wdeprecations] Module `A' is deprecated: bad | 2 | import A | ^^^^^^^^ }}} Observe that after editing the deprecated pragma in {{{A.hs}}} GHC didn't recompile {{{B.hs}}}, meaning that the warning only appeared after I touch'd {{{B.hs}}}. Turning on {{{-Werror}}} turns the problem from one of incorrectly missing warnings to one of incorrect compilation results. I was also got the same results when adding a deprecated pragma to an individual function. My guess is whatever {{{.hi}}} hash you take for recompilation checking should include deprecated pragmas. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14522 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler