diff --git a/src/form_urlencoded.rs b/src/form_urlencoded.rs
index c75ab8b8..cb18aad4 100644
--- a/src/form_urlencoded.rs
+++ b/src/form_urlencoded.rs
@@ -118,7 +118,7 @@ pub fn serialize_with_encoding<'a, I>(pairs: I, encoding_override: Option<::enco
     serialize_internal(pairs, EncodingOverride::from_opt_encoding(encoding_override))
 }
 
-fn serialize_internal<'a, I>(mut pairs: I, encoding_override: EncodingOverride) -> String
+fn serialize_internal<'a, I>(pairs: I, encoding_override: EncodingOverride) -> String
                              where I: Iterator<Item = (&'a str, &'a str)> {
     #[inline]
     fn byte_serialize(input: &str, output: &mut String,
diff --git a/src/parser.rs b/src/parser.rs
index 2ca8f1cf..cc40929a 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -515,7 +515,7 @@ fn parse_path<'a>(base_path: &[String], input: &'a str, context: Context,
         let mut path_part = String::new();
         let mut ends_with_slash = false;
         end = input.len();
-        for (i, c, next_i) in iter {
+        while let Some((i, c, next_i)) = iter.next() {
             match c {
                 '/' => {
                     ends_with_slash = true;
diff --git a/src/tests.rs b/src/tests.rs
index acc10a29..fb4fbb19 100644
--- a/src/tests.rs
+++ b/src/tests.rs
@@ -184,7 +184,7 @@ fn unescape(input: &str) -> String {
                             hex.push(chars.next().unwrap());
                             hex.push(chars.next().unwrap());
                             hex.push(chars.next().unwrap());
-                            from_str_radix(hex.as_slice(), 16)
+                            from_str_radix(hex.as_slice(), 16).ok()
                                 .and_then(char::from_u32).unwrap()
                         }
                         _ => panic!("Invalid test data input"),