#12752: GHC should be able to warn on usafe CPP usage -------------------------------------+------------------------------------- Reporter: erikd | Owner: Type: feature | Status: new request | Priority: normal | Milestone: Component: Compiler | Version: 8.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Other Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- GCC has a warning `-Wundef` that catches unsafe CPP usage like: {{{#!c #if variable_does_not_exist // something #endif }}} The GCC man page says about `-Wundef`: {{{ -Wundef Warn if an undefined identifier is evaluated in an "#if" directive. }}} Following GCC's lead, GHC should have a similar warning flag to detect and warn about this problem in Haskell code that uses CPP. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12752 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler