Set maximum Rust version to 1.31.0

By setting the minimum Rust version and enforcing it with CI, Alacritty
should hopefully make it possible for maintainers to package the
application even on distributions which are not rolling release.

The 1.31.0 target has been chosen here because it's the first version of
the Rust 2018 release. Bumping this version in the future should be
considered to be a breaking change and should only be done with caution
and in consideration of the supported Rust versions of the major
distributions available.

This fixes #2277.

1 files changed, 5 insertions, 7 deletions

diff --git a/font/src/ft/fc/object_set.rs b/font/src/ft/fc/object_set.rs
index 4ec15feb..2494b582 100644
--- a/font/src/ft/fc/object_set.rs
+++ b/font/src/ft/fc/object_set.rs
@@ -11,18 +11,16 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-use std::ptr::NonNull;
-
 use libc::c_char;
 
 use super::ffi::{FcObjectSet, FcObjectSetAdd, FcObjectSetCreate, FcObjectSetDestroy};
 use foreign_types::ForeignTypeRef;
 
 foreign_type! {
-    pub type ObjectSet {
-        type CType = FcObjectSet;
-        fn drop = FcObjectSetDestroy;
-    }
+    type CType = FcObjectSet;
+    fn drop = FcObjectSetDestroy;
+    pub struct ObjectSet;
+    pub struct ObjectSetRef;
 }
 
 impl ObjectSet {
@@ -33,7 +31,7 @@ impl ObjectSet {
 
 impl Default for ObjectSet {
     fn default() -> Self {
-        ObjectSet(unsafe { NonNull::new(FcObjectSetCreate()).unwrap() })
+        ObjectSet(unsafe { FcObjectSetCreate() })
     }
 }