We want to only run the check if ld is gold.

Fixes the fix to #17962.

(cherry picked from commit d589ef25)

Previously the code generator could produce corrupt C call sequences due
to register overlap between MachOp lowerings and the platform's calling
convention. We fix this using a hack described in Note [Evaluate C-call
arguments before placing in destination registers].

(cherry picked from commit a647bae8)

Previously to merge a set of object files we would invoke the linker as
usual, adding -r to the command-line. However, this can result in
non-sensical command-lines which causes lld to balk (#17962).

To avoid this we introduce a new tool setting into GHC, -pgmlm, which is
the linker which we use to merge object files.

This reverts commit 2290eb02.

(cherry picked from commit f9b7497d)

Leon Schoorl authored 4 years ago and Ben Gamari committed 4 years ago

Fixes #18070

GHC_STAGE is the stage of the compiler we're building, it should be 1,2(,3?).
But make was generating 0 and 1.

Hadrian does this correctly using a similar `+ 1`:
https://gitlab.haskell.org/ghc/ghc/-/blob/eb8115a8c4cbc842b66798480fefc7ab64d31931/hadrian/src/Rules/Generate.hs#L245

(cherry picked from commit a481afef354ca0383477fd20891c2e8eb9ef4449)

Otherwise we use ld.lld, which fails with

  ld.lld: error: -r and --export-dynamic may not be used together

It appears that this was incorrectly reverted in
4186c713.

Stefan Schulze Frielinghaus authored 4 years ago and Ben Gamari committed 4 years ago

Fixes #18266

(cherry picked from commit fc0f6fbc)

Moritz Angermann authored 4 years ago and Ben Gamari committed 4 years ago

mmap may return address all over the place. mmap_next will ensure we get
the next free page after the requested address.

This is especially important for linking on aarch64, where the memory model with PIC
admits relocations in the +-4GB range, and as such we can't work with
arbitrary object locations in memory.

Of note: we map the rts into process space, so any mapped objects must
not be ouside of the 4GB from the processes address space.

(cherry picked from commit aedfeb0b)

When specialising a DFun we must take care to saturate the
unfolding.  See Note [Specialising DFuns] in Specialise.

Fixes #18120

(cherry picked from commit 88e3c815)

This patch is joint work of Alexis King and Simon PJ.  It does some
significant refactoring of the type-class specialiser.  Main highlights:

* We can specialise functions with types like
     f :: Eq a => a -> Ord b => b => blah
  where the classes aren't all at the front (#16473).  Here we can
  correctly specialise 'f' based on a call like
     f @Int @Bool dEqInt x dOrdBool
  This change really happened in an earlier patch
     commit 2d0cf625
     Author: Sandy Maguire <sandy@sandymaguire.me>
     Date:   Thu May 16 12:12:10 2019 -0400
  work that this new patch builds directly on that work, and refactors
  it a bit.

* We can specialise functions with implicit parameters (#17930)
     g :: (?foo :: Bool, Show a) => a -> String
  Previously we could not, but now they behave just like a non-class
  argument as in 'f' above.

* We can specialise under-saturated calls, where some (but not all of
  the dictionary arguments are provided (#17966).  For example, we can
  specialise the above 'f' based on a call
     map (f @Int dEqInt) xs
  even though we don't (and can't) give Ord dictionary.

  This may sound exotic, but #17966 is a program from the wild, and
  showed significant perf loss for functions like f, if you need
  saturation of all dictionaries.

* We fix a buglet in which a floated dictionary had a bogus demand
  (#17810), by using zapIdDemandInfo in the NonRec case of specBind.

* A tiny side benefit: we can drop dead arguments to specialised
  functions; see Note [Drop dead args from specialisations]

* Fixed a bug in deciding what dictionaries are "interesting"; see
  Note [Keep the old dictionaries interesting]

This is all achieved by by building on Sandy Macguire's work in
defining SpecArg, which mkCallUDs uses to describe the arguments of
the call. Main changes:

* Main work is in specHeader, which marched down the [InBndr] from the
  function definition and the [SpecArg] from the call site, together.

* specCalls no longer has an arity check; the entire mechanism now
  handles unders-saturated calls fine.

* mkCallUDs decides on an argument-by-argument basis whether to
  specialise a particular dictionary argument; this is new.
  See mk_spec_arg in mkCallUDs.

It looks as if there are many more lines of code, but I think that
all the extra lines are comments!

(cherry picked from commit 7052d7c7)

This patch is just refactoring: no change in
behaviour.

I removed the rather complicated
    checkConstraintsTcS
    checkTvConstraintsTcS

in favour of simpler functions
    emitImplicationTcS
    emitTvImplicationTcS
    pushLevelNoWorkList

The last of these is a little strange, but overall
it's much better I think.

(cherry picked from commit 9d87ced6)

Ticket #17841 showed that we can get a kind error
in a class signature, but lack an enclosing implication
that binds its skolems.

This patch

* Adds the wrapping implication: the new call to
  checkTvConstraints in tcClassDecl1

* Simplifies the API to checkTvConstraints, which
  was not otherwise called at all.

* Simplifies TcErrors.report_unsolved by *not*
  initialising the TidyEnv from the typechecker lexical
  envt.  It's enough to do so from the free vars of the
  unsolved constraints; and we get silly renamings if
  we add variables twice: once from the lexical scope
  and once from the implication constraint.

(cherry picked from commit 3f431587)

Joshua Price authored 4 years ago and Ben Gamari committed 4 years ago

(cherry picked from commit d6203f24)

Travis Whitaker authored 4 years ago and Ben Gamari committed 4 years ago

(cherry picked from commit 67738db1)
(cherry picked from commit a228d0a83db06fbe81b1c74fe3b1aea3133cee50)

This adopts a patch from NetBSD's packaging fixing the `GhcThreaded`
option of the make build system. In addition we introduce a `ghcThreaded`
option in hadrian's `Flavour` type.

Also fix Hadrian's treatment of the `Use Threaded` entry in `settings`.
Previously it would incorrectly claim `Use Threaded = True` if we were
building the `threaded` runtime way. However, this is inconsistent with
the `make` build system, which defines it to be whether the `ghc`
executable is linked against the threaded runtime.

Fixes #17692.

Metric Decrease:
    T12150
    T12234

(cherry picked from commit aa54d1a2b2d2c89107cfa77d8c14a50d6ee9c140)

(cherry picked from commit 9bdc2a056f459b0e05ddbc49d978dfed547ecc13)

Previously, if a .cmm file *not in the RTS* contained something like:

```cmm
section "rodata" { msg : bits8[] "Test\n"; }
```

It would get compiled by CmmToC into:

```c
ERW_(msg);
const char msg[] = "Test\012";
```

and fail with:

```
/tmp/ghc32129_0/ghc_4.hc:5:12: error:
     error: conflicting types for \u2018msg\u2019
     const char msg[] = "Test\012";
                ^~~

In file included from /tmp/ghc32129_0/ghc_4.hc:3:0: error:

/tmp/ghc32129_0/ghc_4.hc:4:6: error:
     note: previous declaration of \u2018msg\u2019 was here
     ERW_(msg);
          ^

/builds/hsyl20/ghc/_build/install/lib/ghc-8.11.0.20200605/lib/../lib/x86_64-linux-ghc-8.11.0.20200605/rts-1.0/include/Stg.h:253:46: error:
     note: in definition of macro \u2018ERW_\u2019
     #define ERW_(X)   extern       StgWordArray (X)
                                                  ^
```

See the rationale for this on https://gitlab.haskell.org/ghc/ghc/-/wikis/commentary/compiler/backends/ppr-c#prototypes

Now we don't generate these extern declarations (ERW_, etc.) for
top-level data. It shouldn't change anything for the RTS (the only place
we use .cmm files) as it is already special cased in
`GHC.Cmm.CLabel.needsCDecl`. And hand-written Cmm can use explicit
extern declarations when needed.

Note that it allows `cgrun069` test to pass with CmmToC (cf #15467).

(cherry picked from commit 499f3a2829d7c5a047c2ee87377d71ab2ea8c6d9)

We don't want to save both Fn and Dn register sets on x86-64 as they are
aliased to the same arch register (XMMn).

Moreover, when SAVE_STGREGS was used in conjunction with `jump foo [*]`
which makes a set of Cmm registers alive so that they cover all arch
registers used to pass parameter, we could have Fn, Dn and XMMn alive at
the same time. It made the LLVM code generator choke (see #17920).

Now `SAVE_REGS/RESTORE_REGS` and `jump foo [*]` use the same set of
registers.

(cherry picked from commit 54b595c1)

Moritz Angermann authored 4 years ago and Ben Gamari committed 4 years ago

Some platforms (musl, aarch64) do not have a working dynamic linker
implemented in the libc, even though we might see dlopen.  It will
ultimately just return that this is not supported.  Hence we'll add
a flag to the compiler to flat our disable loading dlls.  This is
needed as we will otherwise try to load the shared library even
if this will subsequently fail.  At that point we have given up
looking for static options though.

(cherry picked from commit aef523ea)

Fixes #18281.

(cherry picked from commit 750a1595)

Strangely, the comment next to this code already alluded to the fact
that even simply eta-expanding will sacrifice laziness. It's quite
unclear how we regressed so far.

See #18151.

(cherry picked from commit b1dbd625)

(cherry picked from commit 95a9eb73)

(cherry picked from commit bd9f5589)

Moritz Angermann authored 4 years ago and Ben Gamari committed 4 years ago

See also: https://static.docs.arm.com/ihi0056/g/aaelf64.pdf

(cherry picked from commit f2446ff1)

Moritz Angermann authored 4 years ago and Ben Gamari committed 4 years ago

Some archives contain so called linker objects, with the affectionate
.lo suffic.  For example the musl libc.a will come in that form.  We
still want to load those objects, hence we should not discard them and
look for .lo as well.  Ultimately we might want to fix this proerly by
looking at the file magic.

(cherry picked from commit 3fd12af1)

Moritz Angermann authored 4 years ago and Ben Gamari committed 4 years ago

libm is just an empty shell on musl, and all the math functions are contained in
libc.

(cherry picked from commit b4550748)

Artem Pelenitsyn authored 4 years ago and Ben Gamari committed 4 years ago

author: claude (https://gitlab.haskell.org/trac-claude)

The correct threshold for log1mexp is -(log 2) with the current specification
of log1mexp. This change improves accuracy for large negative inputs.

To avoid code duplication, a small helper function is added;
it isn't the default implementation in Floating because it needs Ord.

This patch does nothing to address that the Haskell specification is
different from that in common use in other languages.

(cherry picked from commit af5e3a88)

Moritz Angermann authored 4 years ago and Ben Gamari committed 4 years ago

Mostly symbols needed for aarch64/armv7l
and in combination with musl, where we have
to rely on loading *all* objects/archives

- __stack_chk_* only when not DYNAMIC

(cherry picked from commit 5bc6082f)

I also took the liberty to do away the fixed buffer size for escaping.
Using a fixed size here can only lead to issues down the line.

Fixes #18438.

(cherry picked from commit fecafac8)