Some parts of the build system require that paths are what msys2 calls
"mixed style":
  * forwards slashes
  * absolute paths starting with a drive letter followed by a colon
    (e.g. "C:")

The removal of ghc-pwd in 4c56ad36 changed $(TOP) from mixed style to
unix style, resulting in a broken Windows build for some.

Differential Revision: https://phabricator.haskell.org/D1752

niteria authored 9 years ago and Ben Gamari committed 9 years ago

This was non-obvious to me when reading the sources and the
paper provides the motivation and explores the design space.

Test Plan: just a comment

Reviewers: simonpj, austin, ezyang, bgamari

Reviewed By: bgamari

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1749

Summary:
Was broken by ce1f1607.  I've added a
test so that hopefully it won't break again.

Test Plan: validate & new test case

Reviewers: bgamari, austin, erikd

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1746

GHC Trac Issues: #11304

Jonas Scholl authored 9 years ago and Ben Gamari committed 9 years ago

Speed up GHC.Event.IntTable.lookup by removing the IO context from the
go helper function. This generates a little bit better code as we can
avoid repeating the stack check.

Remove unused parameter from GHC.Event.IntTable.updateWith.go and
directly return a bool instead of a maybe and then checking that whether
it is a Nothing.

Test Plan: validate

Reviewers: austin, hvr, bgamari

Reviewed By: bgamari

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1742

GHC Trac Issues: #8793

This is the second (and hopefully last) fix needed to make TH handle
GADTs properly (after D1465). This Diff addresses some issues with infix
GADT constructors, specifically:

* Before, you could not determine if a GADT constructor was declared
  infix because TH did not give you the ability to determine if there is
  a //user-specified// fixity declaration for that constructor. The
  return type of `reifyFixity` was changed to `Maybe Fixity` so that it
  yields `Just` the fixity is there is a fixity declaration, and
  `Nothing` otherwise (indicating it has `defaultFixity`).
* `DsMeta`/`Convert` were changed so that infix GADT constructors are
  turned into `GadtC`, not `InfixC` (which should be reserved for
  Haskell98 datatype declarations).
* Some minor fixes to the TH pretty-printer so that infix GADT
  constructors will be parenthesized in GADT signatures.

Fixes #11345.

Test Plan: ./validate

Reviewers: goldfire, austin, bgamari, jstolarek

Reviewed By: jstolarek

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1744

GHC Trac Issues: #11345

Summary: This completes the support for TH with -fexternal-interpreter.

Test Plan: validate

Reviewers: bgamari, ezyang, austin, niteria, goldfire, erikd

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1748

GHC Trac Issues: #11100

Summary:
The main goal here is enable stack traces in GHCi.  After this change,
if you start GHCi like this:

  ghci -fexternal-interpreter -prof

(which requires packages to be built for profiling, but not GHC
itself) then the interpreter manages cost-centre stacks during
execution and can produce a stack trace on request.  Call locations
are available for all interpreted code, and any compiled code that was
built with the `-fprof-auto` familiy of flags.

There are a couple of ways to get a stack trace:

* `error`/`undefined` automatically get one attached
* `Debug.Trace.traceStack` can be used anywhere, and prints the current
  stack

Because the interpreter is running in a separate process, only the
interpreted code is running in profiled mode and the compiler itself
isn't slowed down by profiling.

The GHCi debugger still doesn't work with -fexternal-interpreter,
although this patch gets it a step closer.  Most of the functionality
of breakpoints is implemented, but the runtime value introspection is
still not supported.

Along the way I also did some refactoring and added type arguments to
the various remote pointer types in `GHCi.RemotePtr`, so there's
better type safety and documentation in the bridge code between GHC
and ghc-iserv.

Test Plan: validate

Reviewers: bgamari, ezyang, austin, hvr, goldfire, erikd

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1747

GHC Trac Issues: #11047, #11100

As Trac #11222, and #10712 note, the strictness analyser
needs to be rather careful about exceptions.  Previously
it treated them as identical to divergence, but that
won't quite do.

See Note [Exceptions and strictness] in Demand, which
explains the deal.

Getting more strictness in 'catch' and friends is a
very good thing.  Here is the nofib summary, keeping
only the big ones.

--------------------------------------------------------------------------------
        Program           Size    Allocs   Runtime   Elapsed  TotalMem
--------------------------------------------------------------------------------
          fasta          -0.1%     -6.9%     -3.0%     -3.0%     +0.0%
            hpg          -0.1%     -2.0%     -6.2%     -6.2%     +0.0%
       maillist          -0.1%     -0.3%      0.08      0.09     +1.2%
reverse-complem          -0.1%    -10.9%     -6.0%     -5.9%     +0.0%
         sphere          -0.1%     -4.3%      0.08      0.08     +0.0%
           x2n1          -0.1%     -0.0%      0.00      0.00     +0.0%
--------------------------------------------------------------------------------
            Min          -0.2%    -10.9%    -17.4%    -17.3%     +0.0%
            Max          -0.0%     +0.0%     +4.3%     +4.4%     +1.2%
 Geometric Mean          -0.1%     -0.3%     -2.9%     -3.0%     +0.0%

On the way I did quite a bit of refactoring in Demand.hs

This change tidies up and simplifies (a bit) the knot-tying
when kind-checking groups of type and class declarations.

The trouble (shown by Trac #11356) was that we wanted an error message
(a kind-mismatch) that involved a type mentioned a (AThing k), which
blew up.

Since we now seem to have TcTyCons, I decided to use them here.
It's still not great, but it's easier to understand and more robust.

Trac #11437 showed that erroneous constraints from a 'deriving'
clause need to be wrapped in an Implication to properly scope
their skolems.

The main change is in TcDeriv.simplifyDeriv; the call to
buildImplicationFor is new.

simpl_top was being polluted with Safe Haskell stuff which was only
used in one of its four calls.  This moves the Safe Haskell stuff
to the place it is actually used

It was only called in one place; easier to inline it

Previously tidySkolemInfo used tidyOpenType, and returned a new
TidyEnv.  But that's not needed any more, because all the skolems
should be in scope in the constraint tree.

I also removed a (now-unnecessary) field of UnifyForAllSkol

Incredibly enough this hasn't been touched since 6.10.1

Reviewers: austin, hvr, bgamari, thomie

Reviewed By: thomie

Differential Revision: https://phabricator.haskell.org/D1721

Ben Gamari authored 9 years ago and Ben Gamari committed 9 years ago

Reviewers: hvr, thomie, austin

Reviewed By: austin

Subscribers: duncan

Differential Revision: https://phabricator.haskell.org/D1741

GHC Trac Issues: #8176, #4437

Bump Cabal and Haddock submodules such that they both support GCC-style
response files on Windows.

Previous representation of GADTs in TH was not expressive enough
to express possible GADT return types. See #11341

Test Plan: ./validate

Reviewers: goldfire, austin, bgamari

Subscribers: thomie, RyanGlScott

Differential Revision: https://phabricator.haskell.org/D1738

GHC Trac Issues: #11341

Phab:D493 accidentally changed the way GHC generics looks up `Fixity`
information when deriving `Generic` or `Generic1`. Before, a `Fixity` of
`Infix` would be given only if a data constructor was declared infix,
but now, `Infix` is given to any data constructor that has a fixity
declaration (not to be confused with being declared infix!). This commit
reverts back to the original behavior for consistency's sake.

Fixes #11358.

Test Plan: ./validate

Reviewers: kosmikus, dreixel, austin, bgamari

Reviewed By: bgamari

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1740

GHC Trac Issues: #11358

Duncan Coutts authored 9 years ago and Ben Gamari committed 9 years ago

A set of changes to enable local ghc env files to be useful for tools
like cabal. Ultimately it will allow cabal to maintain a ghc env file so
that users can simple run ghc or ghci in a project directory and get the
expected environment of the project.

Change the name of .ghc.environment files to include the platform and
ghc version, e.g. .ghc.environment.x86_64-linux-7.6.3, since their
content is version specific. Strictly speaking this is not backwards
compatible, but we think this feature is not widely used yet.

"Look up" for a local env file, like the behaviour of git/darcs etc. So
you can be anywhere within a project and get the expected environment.

Don't look for local env files when -hide-all-packages is given.

Extend the syntax of env files to allow specifying package dbs too.

Test Plan:
Currently completely untested. Compiles, that is all.
Sorry, have to disappear for the hols.

Reviewers: hvr, ezyang, austin, bgamari

Reviewed By: ezyang, bgamari

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1668

GHC Trac Issues: #11268

Ben Gamari authored 9 years ago and Ben Gamari committed 9 years ago

The interfaces to {save,load}ThreadState were quite messy due to the
need to pass in local registers (produced with draws from a unique
supply) since they were used from both FCode and UniqSM.

This, however, is entirely unnecessary as we already have an
abstraction to capture this effect: MonadUnique. Use it.

This is part of an effort to properly represent stack unwinding
information
for foreign calls.

Test Plan: validate

Reviewers: austin, simonmar

Reviewed By: simonmar

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1733

Ben Gamari authored 9 years ago and Ben Gamari committed 9 years ago

Various people (myself included) have complained about the lack of
useful descriptions for the various packages included in GHC's source
tree. Fix this.

Test Plan: Validate

Reviewers: austin, thomie

Reviewed By: thomie

Subscribers: angerman, ezyang

Differential Revision: https://phabricator.haskell.org/D1736

Georgios Karachalias authored 9 years ago and Ben Gamari committed 9 years ago

Since #11316 indicates that having flag `-Wtoo-many-guards`
enabled by default causes issues, the simplest thing is to
remove it. This patch removes it from the default list, it
updates the docs and removes the suppression flags for
`T783` and `types/OptCoercion.hs`

Test Plan: validate

Reviewers: bgamari, austin, goldfire

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1737

GHC Trac Issues: #11316

Unfortunately, I could not add the expected error message, so if someone
accidentally fixes this bug, this test will still be failing (no harm).
But maybe someone stumbles over it then and can update the expected
output.