Move `/includes` to `/rts/include`, sort per package betterwip/organize-headers

In order to make the packages in this repo "reinstallable", we need to
associate source code with a specific packages. Having a top level
`/includes` dir that mixes concerns (which packages' includes?) gets in
the way of this.

To start, I have moved everything to `rts/`, which is mostly correct.
There are a few things however that really don't belong in the rts (like
the generated constants haskell type, `CodeGen.Platform.h`). Those
needed to be manually adjusted.

Things of note:

 - No symlinking for sake of windows, so we hard-link at configure time.

 - `CodeGen.Platform.h` no longer as `.hs` extension (in addition to
   being moved to `compiler/`) so as not to confuse anyone, since it is
   next to Haskell files.

 - Blanket `-Iincludes` is gone in both build systems, include paths now
   more strictly respect per-package dependencies.

 - `deriveConstants` has been taught to not require a `--target-os` flag
   when generating the platform-agnostic Haskell type. Make takes
   advantage of this, but Hadrian has yet to.

4 files changed, 7 insertions, 7 deletions

diff --git a/libraries/ghc-heap/GHC/Exts/Heap/ClosureTypes.hs b/libraries/ghc-heap/GHC/Exts/Heap/ClosureTypes.hs
index 1d25abee51..5eefe02d0d 100644
--- a/libraries/ghc-heap/GHC/Exts/Heap/ClosureTypes.hs
+++ b/libraries/ghc-heap/GHC/Exts/Heap/ClosureTypes.hs
@@ -12,7 +12,7 @@ import GHC.Generics
 {- ---------------------------------------------
 -- Enum representing closure types
 -- This is a mirror of:
--- includes/rts/storage/ClosureTypes.h
+-- rts/include/rts/storage/ClosureTypes.h
 -- ---------------------------------------------}
 
 data ClosureType
diff --git a/libraries/ghc-heap/GHC/Exts/Heap/Closures.hs b/libraries/ghc-heap/GHC/Exts/Heap/Closures.hs
index 3b51b22ceb..e15ae7008b 100644
--- a/libraries/ghc-heap/GHC/Exts/Heap/Closures.hs
+++ b/libraries/ghc-heap/GHC/Exts/Heap/Closures.hs
@@ -98,7 +98,7 @@ areBoxesEqual (Box a) (Box b) = case reallyUnsafePtrEqualityUpToTag# a b of
 type Closure = GenClosure Box
 
 -- | This is the representation of a Haskell value on the heap. It reflects
--- <https://gitlab.haskell.org/ghc/ghc/blob/master/includes/rts/storage/Closures.h>
+-- <https://gitlab.haskell.org/ghc/ghc/blob/master/rts/include/rts/storage/Closures.h>
 --
 -- The data type is parametrized by `b`: the type to store references in.
 -- Usually this is a 'Box' with the type synonym 'Closure'.
diff --git a/libraries/ghc-heap/GHC/Exts/Heap/InfoTable/Types.hsc b/libraries/ghc-heap/GHC/Exts/Heap/InfoTable/Types.hsc
index 943a234391..667301157a 100644
--- a/libraries/ghc-heap/GHC/Exts/Heap/InfoTable/Types.hsc
+++ b/libraries/ghc-heap/GHC/Exts/Heap/InfoTable/Types.hsc
@@ -28,7 +28,7 @@ type HalfWord = Word16
 type EntryFunPtr = FunPtr (Ptr () -> IO (Ptr ()))
 
 -- | This is a somewhat faithful representation of an info table. See
--- <https://gitlab.haskell.org/ghc/ghc/blob/master/includes/rts/storage/InfoTables.h>
+-- <https://gitlab.haskell.org/ghc/ghc/blob/master/rts/include/rts/storage/InfoTables.h>
 -- for more details on this data structure.
 data StgInfoTable = StgInfoTable {
    entry  :: Maybe EntryFunPtr, -- Just <=> not TABLES_NEXT_TO_CODE
diff --git a/libraries/ghc-heap/GHC/Exts/Heap/ProfInfo/Types.hs b/libraries/ghc-heap/GHC/Exts/Heap/ProfInfo/Types.hs
index 579d29098c..5ff030d923 100644
--- a/libraries/ghc-heap/GHC/Exts/Heap/ProfInfo/Types.hs
+++ b/libraries/ghc-heap/GHC/Exts/Heap/ProfInfo/Types.hs
@@ -7,14 +7,14 @@ import Data.Word
 import GHC.Generics
 
 -- | This is a somewhat faithful representation of StgTSOProfInfo. See
--- <https://gitlab.haskell.org/ghc/ghc/blob/master/includes/rts/storage/TSO.h>
+-- <https://gitlab.haskell.org/ghc/ghc/blob/master/rts/include/rts/storage/TSO.h>
 -- for more details on this data structure.
 data StgTSOProfInfo = StgTSOProfInfo {
     cccs :: Maybe CostCentreStack
 } deriving (Show, Generic, Eq, Ord)
 
 -- | This is a somewhat faithful representation of CostCentreStack. See
--- <https://gitlab.haskell.org/ghc/ghc/blob/master/includes/rts/prof/CCS.h>
+-- <https://gitlab.haskell.org/ghc/ghc/blob/master/rts/include/rts/prof/CCS.h>
 -- for more details on this data structure.
 data CostCentreStack = CostCentreStack {
     ccs_ccsID :: Int,
@@ -32,7 +32,7 @@ data CostCentreStack = CostCentreStack {
 } deriving (Show, Generic, Eq, Ord)
 
 -- | This is a somewhat faithful representation of CostCentre. See
--- <https://gitlab.haskell.org/ghc/ghc/blob/master/includes/rts/prof/CCS.h>
+-- <https://gitlab.haskell.org/ghc/ghc/blob/master/rts/include/rts/prof/CCS.h>
 -- for more details on this data structure.
 data CostCentre = CostCentre {
     cc_ccID :: Int,
@@ -46,7 +46,7 @@ data CostCentre = CostCentre {
 } deriving (Show, Generic, Eq, Ord)
 
 -- | This is a somewhat faithful representation of IndexTable. See
--- <https://gitlab.haskell.org/ghc/ghc/blob/master/includes/rts/prof/CCS.h>
+-- <https://gitlab.haskell.org/ghc/ghc/blob/master/rts/include/rts/prof/CCS.h>
 -- for more details on this data structure.
 data IndexTable = IndexTable {
     it_cc :: CostCentre,