GitLab

We also need to update `stgBindHasCafRefs` assertion with this change,
as we no longer have the pre-computed SRT, LiveVars etc. We rename it to
`topStgBindHasCafRefs` and implement it like this:

A non-updatable top-level binding may refer to a CAF by referring to a
top-level definition with CAFs. A top-level definition may have CAFs if
it's updatable. At this point (because this is done after TidyPgm)
top-level Ids (whether imported or defined in this module) are
GlobalIds, so the top-levelness test is easy. (see also comments in the
code)

Reviewers: bgamari, simonpj, austin

Reviewed By: simonpj

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1889

GHC Trac Issues: #11550

tyConRolesRepresentational is just a version of tyConRolesX, but
specialised for a Representational argument. Saves a bit of extra
argument passing and pattern matching, and tyConRolesX was often
called when we knew the argument role was Representational.

Rather to my surprise this made the compiler allocate 5% less
for tests T9872{b,c,d}.  At least I think it's this commit.
Good thing, regardless.

   mkTvSubst :: InScopeSet -> TvSubstEnv -> TCvSubst
produces a TCvSubst with an empty CvSubstEnv

..around newtype deriving instances.

See esp the new Note [Newtype-deriving instances]

No change in behaviour

This patch fixes Trac #11523.

* The basic problem was that TcRnTypes.superClassesMightHelp was
  returning True of a Derived constraint, and that led to us
  expanding Given superclasses, which produced the same Derived
  constraint again, and so on infinitely.  We really want to do
  this only if there are unsolve /Wanted/ contraints!

* On the way I made TcSMonad.getUnsolvedInerts a bit more
  discriminating about which Derived equalities it returns;
  see Note [Unsolved Derived equalities] in TcSMonad

* Lots of new comments in TcSMonad.

This is a small refactoring, no change in behaviour.

If we fail to typecheck by blowing the constraint simplifier
iteration limit, we want to see the limit-blowing meessage.
Previously it was being suppressed by the type /error/, which
suppress the iteration-limit /warning/.  Solution: make the
iteration-limit message into an error.

They were excessively verbose.  I've commented them out rather than
deleting so that they can easily be restored.

When investigating Trac #11523 I found that superclass
expansion was a little over-aggressive; we were sort of
unrolling each loop twice.

This patch corrects that, and adds explanatory comments.

Flag up the problem highlighted in Trac #11518 comment:15

This is a more stressful example of T11480.

I missed this on my previous commit, somehow
   2cf3ca Allow foralls in instance decls
Apologies.

This patch finally makes it possible to have explicit
foralls in an instance decl
   instance forall (a :: *). Eq a => Eq [a] where ...

This is useful to allow kind signatures or indeed
explicicit kind for-alls; see Trac #11519

I thought it would be really easy, because an instance
declaration already contains an actual HsSigType, so all
the syntactic baggage is there.  But in fact it turned
out that instance declarations were kind-checked a
little differently, because the body kind of the forall
is 'Constraint' rather than '*'.

So I fixed that.  There a slight kludge
(see Note [Body kind of a HsQualTy], but it's still a
significant improvement.

I also did the usual other round of refactoring,
improved a few error messages, tidied up comments etc.
The only significant aspect of all that was

  * Kill mkNakedSpecSigmaTy, mkNakedPhiTy, mkNakedFunTy
    These function names suggest that they do something
    complicated, but acutally they do nothing. So I
    killed them.

  * Swap the arg order of mkNamedBinder, just so that it is
    convenient to say 'map (mkNamedBinder Invisible) tvs'

  * I had to improve isPredTy, to deal with (illegal)
    types like
       (Eq a => Eq [a]) => blah
    See Note [isPeredTy complications] in Type.hs

Still to come: user manual documentation for the
instance-decl change.

..namely buildImplication.

Plus white space in TcDeriv

Noticed by uselex.rb:
    last_free_capability: [R]: exported from:
        ./rts/dist/build/Capability.o
    shutdownCapability: [R]: exported from:
        ./rts/dist/build/Capability.o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Not used since:

    commit f361281c


    Author: Simon Marlow <marlowsd@gmail.com>
    Date:   Wed Dec 7 11:32:35 2011 +0000

        Do not emit the THREAD_RUNNABLE event; it has no useful semantic content

Noticed by uselex.rb:
    traceEventThreadRunnable: [R]: exported from:
        ./rts/dist/build/Inlines.o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Noticed by uselex.rb:
    ccs_mutex: [R]: exported from:
        ./rts/dist/build/Profiling.thr_p_o
    prof_arena: [R]: exported from:
        ./rts/dist/build/Profiling.p_o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Noticed by uselex.rb:
    blockedThrowTo: [R]: exported from:
        ./rts/dist/build/RaiseAsync.o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

While at is mark 'printRetainer' as 'static'.

Noticed by uselex.rb:
    printRetainer: [R]: exported from:
        ./rts/dist/build/RetainerSet.p_o
    traverseAllRetainerSet: [R]: exported from:
        ./rts/dist/build/RetainerSet.p_o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Noticed by uselex.rb:
    setProgName: [R]: exported from:
        ./rts/dist/build/RtsFlags.o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Noticed by uselex.rb:
    removeFromRunQueue: [R]: exported from:
        ./rts/dist/build/Schedule.o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Was never used looking at history available in git.

While at it marked 'mut_user_time_during_RP' as 'static'.

Noticed by uselex.rb:
    mut_user_time_during_heap_census: [R]: exported from:
        ./rts/dist/build/Stats.p_o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Noticed by uselex.rb:
    wakeBlockingQueue: [R]: exported from:
        ./rts/dist/build/Threads.o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Use of this helper function was removed in:

    commit 3c9fc104


    Author: Brian Brooks <brooks.brian@gmail.com>
    Date:   Thu Jul 10 02:55:33 2014 -0500

        Avoid unnecessary clock_gettime() syscalls in GC stats.

Noticed by uselex.rb:
    getThreadCPUTime: [R]: exported from:
        ./rts/dist/build/posix/GetTime.p_o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Noticed by uselex.rb:
    copied: [R]: exported from:
        ./rts/dist/build/sm/GC.o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Noticed by uselex.rb:
    scavenge_mutable_list: [R]: exported from:
        ./rts/dist/build/sm/Scav.o
    scavenge_mutable_list1: [R]: exported from:
        ./rts/dist/build/sm/Scav.thr_o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Use of these helper functions was removed by
  commit 18896fa2


  Author: Simon Marlow <marlowsd@gmail.com>
  Date:   Wed Feb 2 15:49:55 2011 +0000

Noticed by uselex.rb:
    calcLiveBlocks: [R]: exported from:
        ./rts/dist/build/sm/Storage.o
    calcLiveWords: [R]: exported from:
        ./rts/dist/build/sm/Storage.o
Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Since the whole point of validation is to test the compiler, assertions
should be enabled at least for some part of the build. Previously
assertions were only enabled (1) in stage 2 compiler (2) when "slow"
setting is used. With this patch we enable assertions in stage 1
compiler in all settings, to test them on (1) the compiler itself (2)
the libraries, even with the "fast" setting.

This will make "fast" setting slower, but the difference should be quite
modest - I didn't realize a significant difference in validation times.

Reviewers: bgamari, austin, thomie

Reviewed By: thomie

Differential Revision: https://phabricator.haskell.org/D1890

Fixes #11419

Fixes #11419.

Signed-off-by: Sergei Trofimovich <siarheit@google.com>