Due to a compiler warning, ALPM fails to compile. It's because when PkPackageId *id is initialized, it's with the declaration. Thus, GCC thinks id is unused.

Below is the git diff since I don't see how to add a patch file:
diff --git a/backends/alpm/pk-backend-alpm.c b/backends/alpm/pk-backend-alpm.c
index 95e6d30..c23a4e5 100644
--- a/backends/alpm/pk-backend-alpm.c
+++ b/backends/alpm/pk-backend-alpm.c
@@ -392,7 +392,8 @@ static void
 backend_get_description (PkBackend *backend, const gchar *package_id)
 {
        g_return_if_fail (backend != NULL);
-       PkPackageId *id = pk_package_id_new_from_string (package_id);
+       PkPackageId *id;
+       id = pk_package_id_new_from_string (package_id);
        //pk_backend_description (backend, package_id, "unknown", PK_GROUP_ENUM_PROGRAMMING, "sdgd");
        pk_backend_finished (backend);
 }