"Use of old GNU field designator" build failure(s) — clang 3.6.0

This piece of code is triggering a warning by clang on purpose while gcc does not complain. -Werror is failing the build.
struct Point { int x; }
p = { x: 10 };
PackageVersionSupposed error messageFull log Bug report
filtergen 0.12.4-5.1fg-iptables.c:338:2: error: use of GNU old-style field designator extension [-Werror,-Wgnu-designator] Log 751443
indicator-session 0.3.96-1session-dbus.c:51:8: error: use of GNU old-style field designator extension [-Werror,-Wgnu-designator] Log 751444
libappindicator 0.4.92-3.1app-indicator.c:199:2: error: use of GNU old-style field designator extension [-Werror,-Wgnu-designator] Log 751445
libdbusmenu 12.10.2-1menuitem.c:977:23: error: use of GNU old-style field designator extension [-Werror,-Wgnu-designator] Log
libindicate 0.6.92-2server.c:214:2: error: use of GNU old-style field designator extension [-Werror,-Wgnu-designator] Log 751446
libindicator 0.5.0-2indicator-service.c:103:2: error: use of GNU old-style field designator extension [-Werror,-Wgnu-designator] Log 751447

6 errors