redis: Fix build with clang/x86

Need to link with libatomics for 64bit atomics support
Fixes
i686-yoe-linux/i686-yoe-linux-ld: networking.o: in function `createClient':
| /usr/src/debug/redis/4.0.14-r0/redis-4.0.14/src/networking.c:103: undefined reference to `__atomic_fetch_add_8'

Signed-off-by: Khem Raj <raj.khem@gmail.com>
(cherry picked from commit 2b49254d61ca817799a206cd022617854aa5bc0b)
Signed-off-by: Armin Kuster <akuster808@gmail.com>

meta-oe/recipes-extended/redis/redis/0001-src-Do-not-reset-FINAL_LIBS.patch

@@ -0,0 +1,32 @@
+From 97584e1eb78dc18599534b47b6670c20c63f5ee2 Mon Sep 17 00:00:00 2001
+From: Khem Raj <raj.khem@gmail.com>
+Date: Tue, 10 Sep 2019 20:04:26 -0700
+Subject: [PATCH] src: Do not reset FINAL_LIBS
+
+This helps case where additional libraries are needed to be passed from
+environment to get it going
+
+e.g. -latomic is needed on clang/x86 to provide for 64bit atomics
+
+Upstream-Status: Pending
+Signed-off-by: Khem Raj <raj.khem@gmail.com>
+---
+ src/Makefile | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/Makefile b/src/Makefile
+index 7f7c625..c71dd3b 100644
+--- a/src/Makefile
++++ b/src/Makefile
+@@ -66,7 +66,7 @@ endif
+ 
+ FINAL_CFLAGS=$(STD) $(WARN) $(OPT) $(DEBUG) $(CFLAGS) $(REDIS_CFLAGS)
+ FINAL_LDFLAGS=$(LDFLAGS) $(REDIS_LDFLAGS) $(DEBUG)
+-FINAL_LIBS=-lm
++FINAL_LIBS+=-lm
+ DEBUG=-g -ggdb
+ 
+ ifeq ($(uname_S),SunOS)
+-- 
+2.23.0
+

meta-oe/recipes-extended/redis/redis_4.0.14.bb

@@ -11,6 +11,7 @@ SRC_URI = "http://download.redis.io/releases/${BP}.tar.gz \
            file://lua-update-Makefile-to-use-environment-build-setting.patch \
            file://oe-use-libc-malloc.patch \
            file://Fixed-stack-trace-generation-on-aarch64.patch \
+           file://0001-src-Do-not-reset-FINAL_LIBS.patch \
            file://redis.conf \
            file://init-redis-server \
            file://redis.service \
@@ -25,11 +26,13 @@ SRC_URI[sha256sum] = "1e1e18420a86cfb285933123b04a82e1ebda20bfb0a289472745a08758
 
 inherit autotools-brokensep update-rc.d systemd useradd
 
+FINAL_LIBS_x86_toolchain-clang = "-latomic"
+export FINAL_LIBS
+
 USERADD_PACKAGES = "${PN}"
 USERADD_PARAM_${PN}  = "--system --home-dir /var/lib/redis -g redis --shell /bin/false redis"
 GROUPADD_PARAM_${PN} = "--system redis"
 
-
 REDIS_ON_SYSTEMD = "${@bb.utils.contains('DISTRO_FEATURES', 'systemd', 'true', 'false', d)}"
 
 do_compile_prepend() {