[PATCH 28/46] scripts, lto: re-add gcc-ld

[Jiri Slaby (SUSE)]

From: Andi Kleen <ak@xxxxxxxxxxxxxxx>

The primary goal of the script is to mangle linker command line arguments
into something which gcc understands. Such as converting "-z now" into
"-Wl,-z,now".

The script was removed by commit 86879fd277e8 (scripts: remove obsolete
gcc-ld script) as there was no use in the kernel. It had been added long
time ago to support exactly these lto patches, so we need to add it back
now.

Since the removed version, it is improved a bit:
* some missing linker and gcc command line arguments were added, and
* when V=1 is specified, it prints the final gcc command line

[js] rebase + commit message massage

Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Cc: Michal Marek <michal.lkml@xxxxxxxxxxx>
Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Cc: linux-kbuild@xxxxxxxxxxxxxxx
Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Signed-off-by: Martin Liska <mliska@xxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
 scripts/gcc-ld | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100755 scripts/gcc-ld

diff --git a/scripts/gcc-ld b/scripts/gcc-ld
new file mode 100755
index 000000000000..13e85ece8d04
--- /dev/null
+++ b/scripts/gcc-ld
@@ -0,0 +1,40 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# run gcc with ld options
+# used as a wrapper to execute link time optimizations
+# yes virginia, this is not pretty
+
+ARGS="-nostdlib"
+
+for j in "$@" ; do
+	if [ "$j" = -v ] ; then
+		exec `$CC -print-prog-name=ld` -v
+	fi
+done
+
+while [ "$1" != "" ] ; do
+	case "$1" in
+	-save-temps*|-m32|-m64) N="$1" ;;
+	-r) N="$1" ;;
+	-flinker-output*) N="$1" ;;
+	-[Wg]*) N="$1" ;;
+	-[olv]|-[Ofd]*|-nostdlib) N="$1" ;;
+	--end-group|--start-group|--whole-archive|--no-whole-archive|\
+--no-undefined|--hash-style*|--build-id*|--eh-frame-hdr|-Bsymbolic)
+		 N="-Wl,$1" ;;
+	-[RTFGhIezcbyYu]*|\
+--script|--defsym|-init|-Map|--oformat|-rpath|\
+-rpath-link|--sort-section|--section-start|-Tbss|-Tdata|-Ttext|-soname|\
+--version-script|--dynamic-list|--version-exports-symbol|--wrap|-m|-z)
+		A="$1" ; shift ; N="-Wl,$A,$1" ;;
+	-[m]*) N="$1" ;;
+	-*) N="-Wl,$1" ;;
+	*)  N="$1" ;;
+	esac
+	ARGS="$ARGS $N"
+	shift
+done
+
+[ -n "$V" ] && echo >&2 $CC $ARGS
+
+exec $CC $ARGS
-- 
2.38.1