Use the gold linker for linux/ARM and android/ARM targets.

Fixes #8976 and #9873 by making use of the Binutils ld.gold
linker explicit whenever the target is linux/ARM or android/ARM.
This does not affect iOS where Apple provides its own linker.

In order to achieve this, we need to add `-fuse-ld=gold` to
the SettingsCCompilerLinkFlags setting and set
SettingsLdCommand to `ld.gold` (or `${target}-ld.gold` when
cross-compiling). In addition, simplifying the use of
`$(CONF_GCC_LINKER_OPTS_STAGEn)`.

This patch was tested by ensuring that the following worked
as expected:

  * Native builds on linux/x86_64 (nothing changed).
  * Native builds on linux/arm (and uses the gold linker).
  * Linux to linux/arm cross compiles (and uses the cross
    gold linker).

Contributions by Ben Gamari, Joachim Breitner and Reid Barton.

Reviewers: nomeata, bgamari, austin, rwbarton

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D715

GHC Trac Issues: #8976 #9873

1 files changed, 5 insertions, 0 deletions

diff --git a/aclocal.m4 b/aclocal.m4
index a4944c1357..871dacc370 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -565,6 +565,11 @@ AC_DEFUN([FPTOOLS_SET_C_LD_FLAGS],
         $3="$$3 -D_HPUX_SOURCE"
         $5="$$5 -D_HPUX_SOURCE"
         ;;
+    arm*linux*)
+        # On arm/linux and arm/android, tell gcc to link using the gold linker.
+        # Forcing LD to be ld.gold is done in configre.ac.
+        $3="$$3 -fuse-ld=gold"
+        ;;
     esac
 
     # If gcc knows about the stack protector, turn it off.