Fix lint errors in primitives

diff --git a/primitives/src/script/builder.rs b/primitives/src/script/builder.rs
index 8703b9e6..f903a2e5 100644
--- a/primitives/src/script/builder.rs
+++ b/primitives/src/script/builder.rs
@@ -31,6 +31,7 @@ impl<T> Builder<T> {
     /// If your pushes should be interpreted as numbers, ensure your input does
     /// not have any leading zeros. In particular, the number 0 should be encoded
     /// as an empty string rather than as a single 0 byte.
+    #[must_use]
     pub fn push_slice<D: AsRef<PushBytes>>(mut self, data: D) -> Self {
         self.0.push_slice(data);
         self
@@ -41,12 +42,14 @@ impl<T> Builder<T> {
     /// Standardness rules require push minimality according to [CheckMinimalPush] of core.
     ///
     /// [CheckMinimalPush]: <https://github.com/bitcoin/bitcoin/blob/99a4ddf5ab1b3e514d08b90ad8565827fda7b63b/src/script/script.cpp#L366>
+    #[must_use]
     pub fn push_slice_non_minimal<D: AsRef<PushBytes>>(mut self, data: D) -> Self {
         self.0.push_slice_non_minimal(data);
         self
     }
 
     /// Adds a single opcode to the script.
+    #[must_use]
     pub fn push_opcode(mut self, data: Opcode) -> Self {
         self.0.push_opcode(data);
         self
diff --git a/primitives/src/script/owned.rs b/primitives/src/script/owned.rs
index 4236323c..81e51883 100644
--- a/primitives/src/script/owned.rs
+++ b/primitives/src/script/owned.rs
@@ -250,7 +250,7 @@ impl<T> ScriptBuf<T> {
                 this.push((n % 0x100) as u8);
                 this.push(((n / 0x100) % 0x100) as u8);
                 this.push(((n / 0x10000) % 0x100) as u8);
-                this.push((n / 0x1000000) as u8);
+                this.push((n / 0x0100_0000) as u8);
             }
         }
         // Then push the raw bytes