fix: rust-2018-idioms

Author: mkroening

Cargo.toml

@@ -31,3 +31,6 @@ mmio = []
 nightly = []
 pci = ["dep:pci_types"]
 zerocopy = ["dep:zerocopy", "dep:zerocopy-derive", "endian-num/zerocopy"]
+
+[lints.rust]
+rust_2018_idioms = "warn"

src/bitflags.rs

@@ -84,7 +84,7 @@ macro_rules! virtio_bitflags {
 macro_rules! impl_fmt {
     ($Trait:ident for $SelfT:ty) => {
         impl ::core::fmt::$Trait for $SelfT {
-            fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
+            fn fmt(&self, f: &mut ::core::fmt::Formatter<'_>) -> ::core::fmt::Result {
                 self.0.fmt(f)
             }
         }