[Git][ghc/ghc][wip/marge_bot_batch_merge_job] 5 commits: DeriveFunctor: Check for last type variables using dataConUnivTyVars

Marge Bot (@marge-bot) gitlab at gitlab.haskell.org
Mon Sep 19 09:37:05 UTC 2022



Marge Bot pushed to branch wip/marge_bot_batch_merge_job at Glasgow Haskell Compiler / GHC


Commits:
8a666ad2 by Ryan Scott at 2022-09-18T08:00:44-04:00
DeriveFunctor: Check for last type variables using dataConUnivTyVars

Previously, derived instances of `Functor` (as well as the related classes
`Foldable`, `Traversable`, and `Generic1`) would determine which constraints to
infer by checking for fields that contain the last type variable. The problem
was that this last type variable was taken from `tyConTyVars`. For GADTs, the
type variables in each data constructor are _not_ the same type variables as
in `tyConTyVars`, leading to #22167.

This fixes the issue by instead checking for the last type variable using
`dataConUnivTyVars`. (This is very similar in spirit to the fix for #21185,
which also replaced an errant use of `tyConTyVars` with type variables from
each data constructor.)

Fixes #22167.

- - - - -
78037167 by Vladislav Zavialov at 2022-09-18T08:01:20-04:00
Lexer: pass updated buffer to actions (#22201)

In the lexer, predicates have the following type:
	{ ... } :: user       -- predicate state
		-> AlexInput  -- input stream before the token
		-> Int        -- length of the token
		-> AlexInput  -- input stream after the token
		-> Bool       -- True <=> accept the token
This is documented in the Alex manual.

There is access to the input stream both before and after the token.
But when the time comes to construct the token, GHC passes only the
initial string buffer to the lexer action. This patch fixes it:

	- type Action = PsSpan -> StringBuffer -> Int ->                 P (PsLocated Token)
	+ type Action = PsSpan -> StringBuffer -> Int -> StringBuffer -> P (PsLocated Token)

Now lexer actions have access to the string buffer both before and after
the token, just like the predicates. It's just a matter of passing an
additional function parameter throughout the lexer.

- - - - -
75746594 by Vladislav Zavialov at 2022-09-18T08:01:20-04:00
Lexer: define varsym without predicates (#22201)

Before this patch, the varsym lexing rules were defined as follows:

	<0> {
	  @varsym / { precededByClosingToken `alexAndPred` followedByOpeningToken } { varsym_tight_infix }
	  @varsym / { followedByOpeningToken }  { varsym_prefix }
	  @varsym / { precededByClosingToken }  { varsym_suffix }
	  @varsym                               { varsym_loose_infix }
	}

Unfortunately, this meant that the predicates 'precededByClosingToken' and
'followedByOpeningToken' were recomputed several times before we could figure
out the whitespace context.

With this patch, we check for whitespace context directly in the lexer
action:

	<0> {
	  @varsym { with_op_ws varsym }
	}

The checking for opening/closing tokens happens in 'with_op_ws' now,
which is part of the lexer action rather than the lexer predicate.

- - - - -
ffae25da by M Farkas-Dyck at 2022-09-19T05:36:45-04:00
Scrub partiality about `NewOrData`.

Rather than a list of constructors and a `NewOrData` flag, we define `data DataDefnCons a = NewTypeCon a | DataTypeCons [a]`, which enforces a newtype to have exactly one constructor.

Closes #22070.

Bump haddock submodule.

- - - - -
3f071471 by Cheng Shao at 2022-09-19T05:36:48-04:00
CmmToC: emit __builtin_unreachable() after noreturn ccalls

Emit a __builtin_unreachable() call after a foreign call marked as
CmmNeverReturns. This is crucial to generate correctly typed code for
wasm; as for other archs, this is also beneficial for the C compiler
optimizations.

- - - - -


30 changed files:

- compiler/GHC/CmmToC.hs
- compiler/GHC/Hs/Decls.hs
- compiler/GHC/Hs/Utils.hs
- compiler/GHC/HsToCore/Docs.hs
- compiler/GHC/HsToCore/Errors/Ppr.hs
- compiler/GHC/HsToCore/Errors/Types.hs
- compiler/GHC/HsToCore/Quote.hs
- compiler/GHC/Iface/Ext/Ast.hs
- compiler/GHC/Parser.y
- compiler/GHC/Parser/Errors/Ppr.hs
- compiler/GHC/Parser/Errors/Types.hs
- compiler/GHC/Parser/Lexer.x
- compiler/GHC/Parser/PostProcess.hs
- compiler/GHC/Parser/PostProcess/Haddock.hs
- compiler/GHC/Rename/Module.hs
- compiler/GHC/Rename/Names.hs
- compiler/GHC/Rename/Utils.hs
- compiler/GHC/Tc/Deriv/Functor.hs
- compiler/GHC/Tc/Deriv/Generics.hs
- compiler/GHC/Tc/Deriv/Infer.hs
- compiler/GHC/Tc/TyCl.hs
- compiler/GHC/Tc/TyCl/Instance.hs
- compiler/GHC/ThToHs.hs
- compiler/GHC/Types/Error/Codes.hs
- compiler/GHC/Utils/Monad.hs
- compiler/Language/Haskell/Syntax/Decls.hs
- + testsuite/tests/deriving/should_compile/T22167.hs
- testsuite/tests/deriving/should_compile/all.T
- testsuite/tests/ghc-api/exactprint/Test20239.stderr
- testsuite/tests/haddock/should_compile_flag_haddock/T17544.stderr


The diff was not included because it is too large.


View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/3f0c994cb7741b08470f187c67f237d039160708...3f0714717fa33beab9f36aeb32925f8af39d5d78

-- 
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/3f0c994cb7741b08470f187c67f237d039160708...3f0714717fa33beab9f36aeb32925f8af39d5d78
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