Rip out object splitting

The splitter is an evil Perl script that processes assembler code.
Its job can be done better by the linker's --gc-sections flag. GHC
passes this flag to the linker whenever -split-sections is passed on
the command line.

This is based on @DemiMarie's D2768.

Fixes Trac #11315
Fixes Trac #9832
Fixes Trac #8964
Fixes Trac #8685
Fixes Trac #8629

4 files changed, 8 insertions, 21 deletions

diff --git a/docs/storage-mgt/rp.tex b/docs/storage-mgt/rp.tex
index 2f83532893..199b284b19 100644
--- a/docs/storage-mgt/rp.tex
+++ b/docs/storage-mgt/rp.tex
@@ -173,7 +173,6 @@ Installing the GHC is done as follows:
 \begin{code}
 ./fptools/mk    vi build.mk
     GhcHcOpts = -O -fasm -Rghc-timing
-    SplitObjs = NO
     GhcRtsHcOpts = 
     GhcRtsCcOpts = -g
     STRIP_CMD =:
diff --git a/docs/users_guide/8.8.1-notes.rst b/docs/users_guide/8.8.1-notes.rst
index c5bc89a586..8ca0433ba4 100644
--- a/docs/users_guide/8.8.1-notes.rst
+++ b/docs/users_guide/8.8.1-notes.rst
@@ -92,6 +92,11 @@ Compiler
   taking advantage of :extension:`DerivingStrategies`. The warning is supplied at each
   ``deriving`` site.
 
+- Support for object splitting with the flag ``-split-objs`` is removed.  Using
+  this flag now results in a warning and does nothing.  Use
+  :ghc-flag:`-split-sections` instead.
+
+
 Runtime system
 ~~~~~~~~~~~~~~
 
diff --git a/docs/users_guide/packages.rst b/docs/users_guide/packages.rst
index 632162f6c8..9383b8ad68 100644
--- a/docs/users_guide/packages.rst
+++ b/docs/users_guide/packages.rst
@@ -1023,9 +1023,9 @@ extra indirection).
    ``HSfoo.o`` file that has been pre-linked. Loading the ``.o`` file is
    slightly quicker, but at the expense of having another copy of the
    compiled package. The rule of thumb is that if the modules of the
-   package were compiled with :ghc-flag:`-split-objs` then building the
+   package were compiled with :ghc-flag:`-split-sections` then building the
    ``HSfoo.o`` is worthwhile because it saves time when loading the
-   package into GHCi. Without :ghc-flag:`-split-objs`, there is not much
+   package into GHCi. Without :ghc-flag:`-split-sections`, there is not much
    difference in load time between the ``.o`` and ``.a`` libraries, so
    it is better to save the disk space and only keep the ``.a`` around.
    In a GHC distribution we provide ``.o`` files for most packages
diff --git a/docs/users_guide/phases.rst b/docs/users_guide/phases.rst
index f5f735b81b..0f70368047 100644
--- a/docs/users_guide/phases.rst
+++ b/docs/users_guide/phases.rst
@@ -732,21 +732,6 @@ for example).
     option for Apple's Linker (``-F`` already means something else for
     GHC).
 
-.. ghc-flag:: -split-objs
-    :shortdesc: Split objects (for libraries)
-    :type: dynamic
-    :category: linking
-
-    Tell the linker to split the single object file that would normally
-    be generated into multiple object files, one per top-level Haskell
-    function or type in the module. This only makes sense for libraries,
-    where it means that executables linked against the library are
-    smaller as they only link against the object files that they need.
-    However, assembling all the sections separately is expensive, so
-    this is slower than compiling normally. Additionally, the size of
-    the library itself (the ``.a`` file) can be a factor of 2 to 2.5
-    larger.
-
 .. ghc-flag:: -split-sections
     :shortdesc: Split sections for link-time dead-code stripping
     :type: dynamic
@@ -758,9 +743,7 @@ for example).
     output file.
 
     When linking, the linker can automatically remove all unreferenced sections
-    and thus produce smaller executables. The effect is similar to
-    :ghc-flag:`-split-objs`, but somewhat more efficient - the generated library
-    files are about 30% smaller than with :ghc-flag:`-split-objs`.
+    and thus produce smaller executables.
 
 .. ghc-flag:: -static
     :shortdesc: Use static Haskell libraries