Touch up PR 1997

serde/build.rs

@@ -76,7 +76,7 @@ fn main() {
         println!("cargo:rustc-cfg=serde_derive");
     }
 
-    // TryFrom, Atomic types, non-zero signed integers, and `SystemTime::checked_add`
+    // TryFrom, Atomic types, non-zero signed integers, and SystemTime::checked_add
     // stabilized in Rust 1.34:
     // https://blog.rust-lang.org/2019/04/11/Rust-1.34.0.html#tryfrom-and-tryinto
     // https://blog.rust-lang.org/2019/04/11/Rust-1.34.0.html#library-stabilizations

serde/src/de/impls.rs

@@ -2130,7 +2130,7 @@ impl<'de> Deserialize<'de> for SystemTime {
         #[cfg(systemtime_checked_add)]
         let ret = UNIX_EPOCH
             .checked_add(duration)
-            .ok_or(D::Error::custom("overflow deserializing SystemTime"));
+            .ok_or_else(|| D::Error::custom("overflow deserializing SystemTime"));
         #[cfg(not(systemtime_checked_add))]
         let ret = Ok(UNIX_EPOCH + duration);
         ret