Summary: Set THREADS=CPUS+1 in circleci.

Reviewers: bgamari

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4415

Previously, we were extracting the free variables from a
GADT constructor in an incorrect order, which caused the type
variables for the constructor's type signature to end up in
non-toposorted order. Thankfully, rearranging the order of types
during renaming makes swift work of this bug.

This fixes a regression introduced in commit
fa29df02.
For whatever reason, that commit also commented out a
significant portion of the `T13123` test. This code appears
to work, so I've opted to uncomment it.

Test Plan: make test TEST=T14808

Reviewers: simonpj, bgamari

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

GHC Trac Issues: #14808

Differential Revision: https://phabricator.haskell.org/D4413

- Remove all type checks
- Check two STG invariants (no unboxed let bindings, variables defined
  before used) and post-unarisation invariants.

See the module header and #14787.

This version validates with `-dstg-lint` added to `GhcStage2HcOpts` and
`GhcLibHcOpts` and `EXTRA_HC_OPTS`.

Unarise changes:

- `unariseConArgBinder` and `unariseFunArgBinder` functions were almost
  the same; only difference was when unarising fun args we keep void
  args while in con args we drop them. A new function `unariseArgBinder`
  added with a `Bool` argument for whether we're unarising a con arg.
  `unariseConArgBinder` and `unariseFunArgBinder` are now defined as

      unariseConArgBinder = unarsieArgBinder True  -- data con
      unariseFunArgBinder = unariseArgBinder False -- not data con

- A bug in `unariseConArgBinder` and `unariseFunArgBinder` (which are
  just calls to `unariseArgBinder` now) that invalidated the
  post-unarise invariants when the argument has single type rep (i.e.
  `length (typePrimRep x) == 1`) fixed. This isn't a correctness issue
  (it's fine not to unarise if a variable is already represented as
  single value), but it triggers StgLint.

Test Plan:
- Pass testsuite with `-dstg-lint` [done]
- Boot stage2 (including libraries) with `-dstg-lint` [done]

Reviewers: simonpj, bgamari

Reviewed By: bgamari

Subscribers: duog, rwbarton, thomie, carter

GHC Trac Issues: #14787

Differential Revision: https://phabricator.haskell.org/D4404

Print different error message for improper UNPACK and strictness
annotations.  Fix Trac #14761.

Signed-off-by: HE, Tao <sighingnow@gmail.com>

Test Plan: make test TEST="T7210 T14761a T14761b"

Reviewers: goldfire, bgamari, RyanGlScott, simonpj

Reviewed By: RyanGlScott, simonpj

Subscribers: simonpj, goldfire, rwbarton, thomie, carter

GHC Trac Issues: #14761

Differential Revision: https://phabricator.haskell.org/D4397

Douglas Wilson authored 7 years ago and Ben Gamari committed 7 years ago

Reviewers: bgamari

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4389

Michal Terepeta authored 7 years ago and Ben Gamari committed 7 years ago

During some recent work on CBE we discovered that `zipWith` is used to
check for equality, but that doesn't quite work if lists are of
different lengths! This was fixed by bgamari, but unfortunately the fix
had to be rolled back due to other changes in CBE in
50adbd7c. Since I wanted to have another
look at CBE anyway, we agreed that the first thing to do would be to
re-introduce the fix.

Sadly I don't have any actual test case that would exercise this.

Signed-off-by: Michal Terepeta <michal.terepeta@gmail.com>

Test Plan: ./validate

Reviewers: bgamari, simonmar

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

GHC Trac Issues: #14226

Differential Revision: https://phabricator.haskell.org/D4387

Simon Marlow authored 7 years ago and Ben Gamari committed 7 years ago

The pattern `threadCapability =<< myThreadId` is used a lot in code
that uses `hs_try_putmvar`, I want to make it cheaper.

Test Plan: validate

Reviewers: bgamari, erikd

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4381

Simon Marlow authored 7 years ago and Ben Gamari committed 7 years ago

Test Plan: validate

Reviewers: bgamari, erikd

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4380

adam authored 7 years ago and Ben Gamari committed 7 years ago

Reviewers: bgamari

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4368

Ben Gamari authored 7 years ago and Ben Gamari committed 7 years ago

By request of @alexbiehl.
CCing @snowleopard and @alpmestan as the same should be done in Hadrian.

Bumps haddock submodule.

Reviewers: alexbiehl

Reviewed By: alexbiehl

Subscribers: rwbarton, thomie, carter, snowleopard, alpmestan, alexbiehl

Differential Revision: https://phabricator.haskell.org/D4365

Matthías Páll Gissurarson authored 7 years ago and Ben Gamari committed 7 years ago

This adds valid refinement substitution suggestions for typed holes and
documentation thereof.

Inspired by Agda's refinement facilities, this extends the typed holes
feature to be able to search for valid refinement substitutions, which
are substitutions that have one or more holes in them.

When the flag `-frefinement-level-substitutions=n` where `n > 0` is
passed, we also look for valid refinement substitutions, i.e.
substitutions that are valid, but adds more holes. Consider the
following:

  f :: [Integer] -> Integer
  f = _

Here the valid substitutions suggested will be (with the new
`-funclutter-valid-substitutions` flag for less verbosity set):

```
  Valid substitutions include
    f :: [Integer] -> Integer
    product :: forall (t :: * -> *).
              Foldable t => forall a. Num a => t a -> a
    sum :: forall (t :: * -> *).
          Foldable t => forall a. Num a => t a -> a
    maximum :: forall (t :: * -> *).
              Foldable t => forall a. Ord a => t a -> a
    minimum :: forall (t :: * -> *).
              Foldable t => forall a. Ord a => t a -> a
    head :: forall a. [a] -> a
    (Some substitutions suppressed; use -fmax-valid-substitutions=N or
-fno-max-valid-substitutions)
```

When the `-frefinement-level-substitutions=1` flag is given, we
additionally compute and report valid refinement substitutions:

```
  Valid refinement substitutions include
    foldl1 _ :: forall (t :: * -> *).
                Foldable t => forall a. (a -> a -> a) -> t a -> a
    foldr1 _ :: forall (t :: * -> *).
                Foldable t => forall a. (a -> a -> a) -> t a -> a
    head _ :: forall a. [a] -> a
    last _ :: forall a. [a] -> a
    error _ :: forall (a :: TYPE r).
                GHC.Stack.Types.HasCallStack => [Char] -> a
    errorWithoutStackTrace _ :: forall (a :: TYPE r). [Char] -> a
    (Some refinement substitutions suppressed; use
-fmax-refinement-substitutions=N or -fno-max-refinement-substitutions)
```

Which are substitutions with holes in them. This allows e.g. beginners
to discover the fold functions and similar.

We find these refinement suggestions by considering substitutions that
don't fit the type of the hole, but ones that would fit if given an
additional argument. We do this by creating a new type variable with
newOpenFlexiTyVarTy (e.g. `t_a1/m[tau:1]`), and then considering
substitutions of the type `t_a1/m[tau:1] -> v` where `v` is the type of
the hole. Since the simplifier is free to unify this new type variable
with any type (and it is cloned before each check to avoid
side-effects), we can now discover any identifiers that would fit if
given another identifier of a suitable type. This is then generalized
so that we can consider any number of additional arguments by setting
the `-frefinement-level-substitutions` flag to any number, and then
considering substitutions like e.g. `foldl _ _` with two additional
arguments.

This can e.g. help beginners discover the `fold` functions.
This could also help more advanced users figure out which morphisms
they can use when arrow chasing.
Then you could write `m = _ . m2 . m3` where `m2` and `m3` are some
morphisms, and not only get exact fits, but also help in finding
morphisms that might get you a little bit closer to where you want to
go in the diagram.

Reviewers: bgamari

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4357

It turns out that one can produce ill-formed Core by
combining `GeneralizedNewtypeDeriving`, `TypeInType`, and
`TypeFamilies`, as demonstrated in #14728. The root of the problem
is allowing the last parameter of a class to appear in a //kind// of
an associated type family, as our current approach to deriving
associated type family instances simply doesn't work well for that
situation.

Although it might be possible to properly implement this feature
today (see https://ghc.haskell.org/trac/ghc/ticket/14728#comment:3
for a sketch of how this might work), there does not currently exist
a performant implementation of the algorithm needed to accomplish
this. Until such an implementation surfaces, we will make this corner
case of `GeneralizedNewtypeDeriving` an error.

Test Plan: make test TEST="T14728a T14728b"

Reviewers: bgamari

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

GHC Trac Issues: #14728

Differential Revision: https://phabricator.haskell.org/D4402

This change is present in 4.11.0.0.

Ryan Scott authored 7 years ago and David Feuer committed 7 years ago

Previously, we were skipping over `$tcUnit#` entirely when
wiring in `Typeable` tycons, resulting in #14811. Easily fixed.

Test Plan: make test TEST=T14811

Reviewers: bgamari, dfeuer

Reviewed By: dfeuer

Subscribers: dfeuer, rwbarton, thomie, carter

GHC Trac Issues: #14811

Differential Revision: https://phabricator.haskell.org/D4414

This is done for consistency. We usually call the package file the same name the
folder has.  The move into `utils` is done so that we can move the library into
`libraries/iserv` and the proxy into `utils/iserv-proxy` and then break the
`iserv.cabal` apart.  This will make building the cross compiler with TH
simpler, because we can build the library and proxy as separate packages.

Reviewers: bgamari, simonmar, goldfire, erikd

Reviewed By: simonmar

Subscribers: tdammers, rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4377

GHC didn't inline `eqTypeRep`, presumably because it ended up
being too big. This was unfortunate because it produces a
`Maybe`, which will almost always be scrutinized immediately.

Split `eqTypeRep` into a worker and a tiny wrapper, and mark the
wrapper `INLINABLE`. This change actually seems to reduce Core size,
at least in a small test.

Reviewers: hvr, bgamari, mpickering

Reviewed By: mpickering

Subscribers: mpickering, rwbarton, thomie, carter

GHC Trac Issues: #14790

Differential Revision: https://phabricator.haskell.org/D4405

Alp Mestanogullari authored 7 years ago and Moritz Angermann committed 7 years ago

The make build system appears to be doing a bit of magic in order to supply
the profiled flavours of libHSrts and libCffi, as they're not advertised in
the 'extra-library-flavours' field of rts.cabal.in. This patch explicitly
advertises _p and _thr_p flavours of the RTS library and libCffi, but only
when the RTS is configured with the (newly introduced) 'profiling' flag.

This is necessary for Hadrian, as a branch (soon to be merged) does away with
ghc-cabal and relies just on Cabal to get package information. Without this
patch, Cabal can never inform us that _p and _thr_p flavours should be
built (and registered in the package db) as well, which obviously prevents us
from building a profiled GHC.

Reviewers: bgamari, erikd, simonmar

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4409

cabal introduces SPDX identifier, and as such we need to change the
BSD3 license name. Also the >= qualifier is no longer prefered.

Test Plan: ./validate

Reviewers: bgamari, erikd, simonmar

Reviewed By: bgamari

Subscribers: alpmestan, rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4406

Reviewers: bgamari, erikd, simonmar

Reviewed By: simonmar

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4393

Reviewers: bgamari, hvr

Reviewed By: bgamari

Subscribers: erikd, hvr, rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4378

Sergey Vinokurov authored 7 years ago and Ben Gamari committed 7 years ago

 * Fix missing code example in changelog for 8.4.1

 * List 'setEnv' as opposite of 'getEnv'

   It seems best to direct users to use 'System.Environment.setEnv'
   rather than 'System.Posix.Env.putEnv'. This is due to 'setEnv' being
   located in the same module as 'getEnv' and my virtue of working on
   Windows platform, whereas 'putEnv' does not have that quality because
   it's part of the 'unix' package.

 * Reflect in docs the fact that 'readMVar' is not a composition of
   'takeMVVar' and 'putMVar' any more

Empty GADTs data declarations can't be identified in type checker. This
patch adds additional checks in parser and raise a parse error when
encounter empty GADTs declarations but extension `GADTs` is not enabled.

Only empty declarations are checked in parser to avoid affecting
existing
error messages related to missing GADTs extension.

This patch should fix issue 8258.

Signed-off-by: HE, Tao <sighingnow@gmail.com>

Test Plan: make test TEST="T8258 T8258NoGADTs"

Reviewers: bgamari, mpickering, alanz, RyanGlScott

Reviewed By: bgamari, RyanGlScott

Subscribers: adamse, RyanGlScott, rwbarton, thomie, mpickering, carter

GHC Trac Issues: #8258

Differential Revision: https://phabricator.haskell.org/D4350

This patch includes two changes:

1. Move cost centre collection from `SCCfinal` to `CorePrep`, to be able
   to collect cost centres in unfoldings. `CorePrep` drops unfoldings, so
   that's the latest stage in the compilation pipeline for this.

   After this change `SCCfinal` no longer collects all cost centres, but
   it still generates & collects CAF cost centres + updates cost centre
   stacks of `StgRhsClosure` and `StgRhsCon`s.

   This fixes #5889.

2. Initialize cost centre stack fields of `StgRhs` in `coreToStg`. With
   this we no longer need to update cost centre stack fields in
   `SCCfinal`, so that module is removed.

   Cost centre initialization explained in Note [Cost-centre
   initialization plan].

   Because with -fcaf-all we need to attach a new cost-centre to each
   CAF, `coreTopBindToStg` now returns `CollectedCCs`.

Test Plan: validate

Reviewers: simonpj, bgamari, simonmar

Reviewed By: simonpj, bgamari

Subscribers: rwbarton, thomie, carter

GHC Trac Issues: #5889

Differential Revision: https://phabricator.haskell.org/D4325

Now that `($)` is representation-polymorphic, `($!)` should
surely follow suit.

Reviewers: hvr, bgamari, simonpj

Reviewed By: bgamari, simonpj

Subscribers: simonpj, rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4382

`NO_PROMOTE_THUNKS` is never defined

Reviewers: hvr, bgamari, RyanGlScott

Reviewed By: RyanGlScott

Subscribers: RyanGlScott, rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4401

When finishing up an implication constraint, it's a bit tricky to
decide which Derived constraints to retain (for error reporting) and
which to discard.  I got this wrong in commit
   f20cf982
   (Remove wc_insol from WantedConstraints)

The particular problem in Trac #14763 was that we were reporting as an
error a fundep-generated constraint
  (ex ~ T)
where 'ex' is an existentially-bound variable in a pattern match.
But this isn't really an error at all.

This patch fixes the problem. Indeed, since I had to understand
this rather tricky code, I took the opportunity to clean it up
and document better.  See
  isDroppableCt :: Ct -> Bool
and Note [Dropping derived constraints]

I also removed wl_deriv altogether from the WorkList data type.  It
was there in the hope of gaining efficiency by not even processing
lots of derived constraints, but it has turned out that most derived
constraints (notably equalities) must be processed anyway; see
Note [Prioritise equalities] in TcSMonad.

The two are coupled because to decide which constraints to put in
wl_deriv I was using another variant of isDroppableCt.  Now it's much
simpler -- and perhaps even more efficient too.

Douglas Wilson authored 7 years ago and Tamar Christina committed 7 years ago

Summary: See definition of PRINTF above the change

Reviewers: bgamari, erikd, simonmar, Phyx

Reviewed By: Phyx

Subscribers: Phyx, rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4392

This was an oversight from 2671cccd
as it wasn't obvious to assume one would go the trouble to manually
construct the pkg-db entries... :-)

This patch fixes the redundant superclass expansion
in Trac #14774.

The main change is to fix TcInterac.solveOneFromTheOther, so
that it does not prefer a work-item with a binding if that binding
transitively depends on the inert item we are comparing it with.

Explained in Note [Replacement vs keeping] in TcInert, esp
item (c) of the "Constraints coming from the same level" part.

To make this work I refactored out a new function
TcEvidence.findNeededEvVars, which was previously buried
inside TcSimplify.neededEvVars.

I added quite a few more comments and signposts about superclass
expansion.

In prelRules we had:

  tx_con_tte :: DynFlags -> AltCon -> AltCon
  tx_con_tte _      DEFAULT      = DEFAULT
  tx_con_tte dflags (DataAlt dc)
    | tag == 0  = DEFAULT   -- See Note [caseRules for tagToEnum]
    | otherwise = LitAlt (mkMachInt dflags (toInteger tag))

The tag==0 case is totally wrong, and led directly to Trac #14768.

See "Beware" in Note [caseRules for tagToEnum] (in the patch).

Easily fixed, though!

Douglas Wilson authored 7 years ago and Ben Gamari committed 7 years ago

Reviewers: bgamari, erikd, simonmar

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4390