diff --git a/pyo3-derive-backend/Cargo.toml b/pyo3-derive-backend/Cargo.toml
index 8466d992..73b61e88 100644
--- a/pyo3-derive-backend/Cargo.toml
+++ b/pyo3-derive-backend/Cargo.toml
@@ -15,7 +15,7 @@ log="0.4"
 quote="0.6"
 
 [dependencies.proc-macro2]
-version = "0.4"
+version = "0.4.9"
 features = ["nightly"]
 
 [dependencies.syn]
diff --git a/pyo3cls/Cargo.toml b/pyo3cls/Cargo.toml
index 775689df..9854b570 100644
--- a/pyo3cls/Cargo.toml
+++ b/pyo3cls/Cargo.toml
@@ -25,5 +25,5 @@ path = "../pyo3-derive-backend"
 version = "0.3.2"
 
 [dependencies.proc-macro2]
-version = "0.4"
+version = "0.4.9"
 features= ["nightly"]