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

From: James Hogan
Date: Tue Mar 08 2016 - 11:48:45 EST

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, ".");