"Use of old GNU field designator" build failure(s) — clang 3.8.1

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
libdbusmenu 12.10.2-1menuitem.c:977:23: error: use of GNU old-style field designator extension [-Werror,-Wgnu-designator] Log

1 errors