diff --git a/serde_codegen/Cargo.toml b/serde_codegen/Cargo.toml
index 4217841d..ca8b7581 100644
--- a/serde_codegen/Cargo.toml
+++ b/serde_codegen/Cargo.toml
@@ -25,5 +25,5 @@ clippy = { version = "^0.*", optional = true }
 quote = "0.3.8"
 serde_codegen_internals = { version = "=0.11.3", default-features = false, path = "../serde_codegen_internals" }
 syn = { version = "0.10", features = ["aster", "visit"] }
-syntex = { version = "^0.52.0", optional = true }
-syntex_syntax = { version = "^0.52.0", optional = true }
+syntex = { version = "^0.54.0", optional = true }
+syntex_syntax = { version = "^0.54.0", optional = true }
diff --git a/serde_codegen/src/lib.rs b/serde_codegen/src/lib.rs
index 797082b7..f920dda5 100644
--- a/serde_codegen/src/lib.rs
+++ b/serde_codegen/src/lib.rs
@@ -116,7 +116,7 @@ macro_rules! shim {
 
             use syntax::{attr, ast, visit};
             struct MarkSerdeAttributesUsed;
-            impl visit::Visitor for MarkSerdeAttributesUsed {
+            impl<'a> visit::Visitor<'a> for MarkSerdeAttributesUsed {
                 fn visit_attribute(&mut self, attr: &ast::Attribute) {
                     if attr.value.name == "serde" {
                         if let ast::MetaItemKind::List(..) = attr.value.node {