Add prelude imports to nested content modules

serde/src/private/de.rs

@@ -216,6 +216,10 @@ mod content {
 
     use crate::lib::*;
 
+    // Explicit prelude import for wasm32v1-none and other no_std targets
+    #[allow(unused_imports)]
+    use ::core::prelude::rust_2021::*;
+
     use crate::de::{
         self, Deserialize, DeserializeSeed, Deserializer, EnumAccess, Expected, IgnoredAny,
         MapAccess, SeqAccess, Unexpected, Visitor,

serde/src/private/ser.rs

@@ -343,6 +343,10 @@ where
 mod content {
     use crate::lib::*;
 
+    // Explicit prelude import for wasm32v1-none and other no_std targets
+    #[allow(unused_imports)]
+    use ::core::prelude::rust_2021::*;
+
     use crate::ser::{self, Serialize, Serializer};
 
     pub struct SerializeTupleVariantAsMapValue<M> {