1. 16 Jan, 2016 3 commits
    • Simon Peyton Jones's avatar
      Fix a number of subtle solver bugs · 9308c736
      Simon Peyton Jones authored
      As a result of some other unrelated changes I found that
      IndTypesPerf was failing, and opened Trac #11408.  There's
      a test in indexed-types/should-compile/T11408.
      
      The bug was that a type like
       forall t. (MT (UL t) (UR t) ~ t) => UL t -> UR t -> Int
      is in fact unambiguous, but it's a bit subtle to prove
      that it is unambiguous.
      
      In investigating, Dimitrios and I found several subtle
      bugs in the constraint solver, fixed by this patch
      
      * canRewrite was missing a Derived/Derived case.  This was
        lost by accident in Richard's big kind-equality patch.
      
      * Interact.interactTyVarEq would discard [D] a ~ ty if there
        was a [W] a ~ ty in the inert set.  But that is wrong because
        the former can rewrite things that the latter cannot.
        Fix: a new function eqCanDischarge
      
      * In TcSMonad.addInertEq, the process was outright wrong for
        a Given/Wanted in the (GWModel) case.  We were adding a new
        Derived without kicking out things that it could rewrite.
        Now the code is simpler (no special GWModel case), and works
        correctly.
      
      * The special case in kickOutRewritable for [W] fsk ~ ty,
        turns out not to be needed.  (We emit a [D] fsk ~ ty which
        will do the job.
      
      I improved comments and documentation, esp in TcSMonad.
      9308c736
    • Alan Zimmerman's avatar
      Work SourceText in for all integer literals · 3a1babd6
      Alan Zimmerman authored
      Summary:
      Certain syntactic elements have integers in them, such as fixity
      specifications, SPECIALISE pragmas and so on.
      
      The lexer will accept mult-radix literals, with arbitrary leading zeros
      in these.
      
      Bring in a SourceText field to each affected AST element to capture the
      original literal text for use with API Annotations.
      
      Affected hsSyn elements are
      
      ```
           -- See note [Pragma source text]
           data Activation = NeverActive
                           | AlwaysActive
                           | ActiveBefore SourceText PhaseNum
                                -- Active only *strictly before* this phase
                           | ActiveAfter SourceText PhaseNum
                                 -- Active in this phase and later
                           deriving( Eq, Data, Typeable )
                                     -- Eq used in comparing rules in HsDecls
      
           data Fixity = Fixity SourceText Int FixityDirection
             -- Note [Pragma source text]
             deriving (Data, Typeable)
       ```
      
      and
      
      ```
            | HsTickPragma         -- A pragma introduced tick
               SourceText           -- Note [Pragma source text] in BasicTypes
               (StringLiteral,(Int,Int),(Int,Int))
                                                -- external span for this tick
               ((SourceText,SourceText),(SourceText,SourceText))
                  -- Source text for the four integers used in the span.
                  -- See note [Pragma source text] in BasicTypes
               (LHsExpr id)
      ```
      
      Updates haddock submodule
      
      Test Plan: ./validate
      
      Reviewers: goldfire, bgamari, austin
      
      Reviewed By: bgamari
      
      Subscribers: thomie, mpickering
      
      Differential Revision: https://phabricator.haskell.org/D1781
      
      GHC Trac Issues: #11430
      3a1babd6
    • Rik Steenkamp's avatar
      Fix some typos · 148a50b5
      Rik Steenkamp authored
      Differential Revision: https://phabricator.haskell.org/D1785
      148a50b5
  2. 15 Jan, 2016 22 commits
  3. 14 Jan, 2016 12 commits
  4. 13 Jan, 2016 3 commits