[PATCH] ld-version: Fix awk regex compile failure

[James Hogan]

The ld-version.sh script fails on some versions of awk with the
following error, resulting in build failures for MIPS:

awk: scripts/ld-version.sh: line 4: regular expression compile failed (missing '(')

This is due to the regular expression ".*)", meant to strip off the
beginning of the ld version string up to the close bracket, however
brackets have a meaning in regular expressions, so lets escape it so
that awk doesn't expect a corresponding open bracket.

Fixes: ccbef1674a15 ("Kbuild, lto: add ld-version and ld-ifversion ...")
Reported-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Signed-off-by: James Hogan <james.hogan@xxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: Michal Marek <mmarek@xxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
Cc: linux-kbuild@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: <stable@xxxxxxxxxxxxxxx> # 4.4.x-
---
I've only tested this with GNU Awk 4.0.2, which seems a bit more
lenient than whatever version of awk Geert's build machine is using.

I'd appreciated if somebody experiencing the error could give this patch
a spin to check it fixes it.
---
 scripts/ld-version.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/ld-version.sh b/scripts/ld-version.sh
index d154f0877fd8..7bfe9fa1c8dc 100755
--- a/scripts/ld-version.sh
+++ b/scripts/ld-version.sh
@@ -1,7 +1,7 @@
 #!/usr/bin/awk -f
 # extract linker version number from stdin and turn into single number
 	{
-	gsub(".*)", "");
+	gsub(".*\\)", "");
 	gsub(".*version ", "");
 	gsub("-.*", "");
 	split($1,a, ".");
-- 
2.4.10