diff --git a/src/od/parse_formats.rs b/src/od/parse_formats.rs
index f8c3659f0..d9731e78d 100644
--- a/src/od/parse_formats.rs
+++ b/src/od/parse_formats.rs
@@ -272,7 +272,7 @@ fn is_format_dump_char(ch: Option<char>, show_ascii_dump: &mut bool) -> bool {
     }
 }
 
-fn parse_type_string(params: &String) -> Result<Vec<ParsedFormatterItemInfo>, String> {
+fn parse_type_string(params: &str) -> Result<Vec<ParsedFormatterItemInfo>, String> {
     let mut formats = Vec::new();
 
     let mut chars = params.chars();
diff --git a/src/od/parse_inputs.rs b/src/od/parse_inputs.rs
index b1ab17427..81409732e 100644
--- a/src/od/parse_inputs.rs
+++ b/src/od/parse_inputs.rs
@@ -131,7 +131,7 @@ pub fn parse_inputs_traditional(input_strings: Vec<String>) -> Result<CommandLin
 }
 
 /// parses format used by offset and label on the commandline
-pub fn parse_offset_operand(s: &String) -> Result<usize, &'static str> {
+pub fn parse_offset_operand(s: &str) -> Result<usize, &'static str> {
     let mut start = 0;
     let mut len = s.len();
     let mut radix = 8;
diff --git a/src/od/parse_nrofbytes.rs b/src/od/parse_nrofbytes.rs
index c934de9c5..766e0924d 100644
--- a/src/od/parse_nrofbytes.rs
+++ b/src/od/parse_nrofbytes.rs
@@ -1,4 +1,4 @@
-pub fn parse_number_of_bytes(s: &String) -> Result<usize, &'static str> {
+pub fn parse_number_of_bytes(s: &str) -> Result<usize, &'static str> {
     let mut start = 0;
     let mut len = s.len();
     let mut radix = 10;
diff --git a/src/printf/memo.rs b/src/printf/memo.rs
index e006f22b5..00d3c6300 100644
--- a/src/printf/memo.rs
+++ b/src/printf/memo.rs
@@ -74,9 +74,9 @@ impl Memo {
             tkn.print(pf_args_it);
         }
     }
-    pub fn run_all(pf_string: &String, pf_args: &[String]) {
+    pub fn run_all(pf_string: &str, pf_args: &[String]) {
         let mut arg_it = pf_args.iter().peekable();
-        let pm = Memo::new(pf_string, &mut arg_it);
+        let pm = Memo::new(&pf_string.to_string(), &mut arg_it);
         loop {
             if arg_it.peek().is_none() {
                 break;
diff --git a/src/printf/tokenize/num_format/num_format.rs b/src/printf/tokenize/num_format/num_format.rs
index 23ca72936..4289ec842 100644
--- a/src/printf/tokenize/num_format/num_format.rs
+++ b/src/printf/tokenize/num_format/num_format.rs
@@ -83,7 +83,7 @@ fn get_provided(str_in_opt: Option<&String>) -> Option<u8> {
 // a base,
 // and an offset for index after all
 //  initial spacing, sign, base prefix, and leading zeroes
-fn get_inprefix(str_in: &String, field_type: &FieldType) -> InPrefix {
+fn get_inprefix(str_in: &str, field_type: &FieldType) -> InPrefix {
     let mut str_it = str_in.chars();
     let mut ret = InPrefix {
         radix_in: Base::Ten,
diff --git a/src/printf/tokenize/sub.rs b/src/printf/tokenize/sub.rs
index 6e5311bf1..fb604bf35 100644
--- a/src/printf/tokenize/sub.rs
+++ b/src/printf/tokenize/sub.rs
@@ -15,12 +15,12 @@ use super::num_format::format_field::{FieldType, FormatField};
 use super::num_format::num_format;
 // use std::collections::HashSet;
 
-fn err_conv(sofar: &String) {
+fn err_conv(sofar: &str) {
     cli::err_msg(&format!("%{}: invalid conversion specification", sofar));
     exit(cli::EXIT_ERR);
 }
 
-fn convert_asterisk_arg_int(asterisk_arg: &String) -> isize {
+fn convert_asterisk_arg_int(asterisk_arg: &str) -> isize {
     // this is a costly way to parse the
     // args used for asterisk values into integers
     // from various bases. Actually doing it correctly
@@ -32,11 +32,11 @@ fn convert_asterisk_arg_int(asterisk_arg: &String) -> isize {
     let field_info = FormatField {
         min_width: Some(0),
         second_field: Some(0),
-        orig: asterisk_arg,
+        orig: &asterisk_arg.to_string(),
         field_type: &field_type,
         field_char: &field_char,
     };
-    num_format::num_format(&field_info, Some(asterisk_arg))
+    num_format::num_format(&field_info, Some(&asterisk_arg.to_string()))
         .unwrap()
         .parse::<isize>()
         .unwrap()
diff --git a/src/sort/sort.rs b/src/sort/sort.rs
index 1bfa13122..54680b8a7 100644
--- a/src/sort/sort.rs
+++ b/src/sort/sort.rs
@@ -49,7 +49,7 @@ struct Settings {
     unique: bool,
     check: bool,
     ignore_case: bool,
-    compare_fns: Vec<fn(&String, &String) -> Ordering>,
+    compare_fns: Vec<fn(&str, &str) -> Ordering>,
 }
 
 impl Default for Settings {
@@ -352,13 +352,13 @@ fn sort_by(lines: &mut Vec<String>, settings: &Settings) {
     lines.sort_by(|a, b| compare_by(a, b, &settings))
 }
 
-fn compare_by(a: &String, b: &String, settings: &Settings) -> Ordering {
+fn compare_by(a: &str, b: &str, settings: &Settings) -> Ordering {
     // Convert to uppercase if necessary
     let (a_upper, b_upper): (String, String);
     let (a, b) = if settings.ignore_case {
         a_upper = a.to_uppercase();
         b_upper = b.to_uppercase();
-        (&a_upper, &b_upper)
+        (&*a_upper, &*b_upper)
     } else {
         (a, b)
     };
@@ -402,7 +402,7 @@ fn default_compare(a: &str, b: &str) -> Ordering {
 /// Compares two floating point numbers, with errors being assumed to be -inf.
 /// Stops coercing at the first whitespace char, so 1e2 will parse as 100 but
 /// 1,000 will parse as -inf.
-fn numeric_compare(a: &String, b: &String) -> Ordering {
+fn numeric_compare(a: &str, b: &str) -> Ordering {
     let fa = permissive_f64_parse(a);
     let fb = permissive_f64_parse(b);
     // f64::cmp isn't implemented because NaN messes with it
@@ -416,7 +416,7 @@ fn numeric_compare(a: &String, b: &String) -> Ordering {
     }
 }
 
-fn human_numeric_convert(a: &String) -> f64 {
+fn human_numeric_convert(a: &str) -> f64 {
     let int_iter = a.chars();
     let suffix_iter = a.chars();
     let int_str: String = int_iter.take_while(|c| c.is_numeric()).collect();
@@ -438,7 +438,7 @@ fn human_numeric_convert(a: &String) -> f64 {
 
 /// Compare two strings as if they are human readable sizes.
 /// AKA 1M > 100k
-fn human_numeric_size_compare(a: &String, b: &String) -> Ordering {
+fn human_numeric_size_compare(a: &str, b: &str) -> Ordering {
     let fa = human_numeric_convert(a);
     let fb = human_numeric_convert(b);
     if fa > fb {
@@ -468,7 +468,7 @@ enum Month {
 }
 
 /// Parse the beginning string into a Month, returning Month::Unknown on errors.
-fn month_parse(line: &String) -> Month {
+fn month_parse(line: &str) -> Month {
     match line.split_whitespace()
         .next()
         .unwrap()
@@ -491,11 +491,11 @@ fn month_parse(line: &String) -> Month {
     }
 }
 
-fn month_compare(a: &String, b: &String) -> Ordering {
+fn month_compare(a: &str, b: &str) -> Ordering {
     month_parse(a).cmp(&month_parse(b))
 }
 
-fn version_compare(a: &String, b: &String) -> Ordering {
+fn version_compare(a: &str, b: &str) -> Ordering {
     let ver_a = Version::parse(a);
     let ver_b = Version::parse(b);
     if ver_a > ver_b {
diff --git a/src/tsort/tsort.rs b/src/tsort/tsort.rs
index dc1dd7192..b24ce5007 100644
--- a/src/tsort/tsort.rs
+++ b/src/tsort/tsort.rs
@@ -135,12 +135,12 @@ impl Graph {
         self.in_edges.get(to).unwrap().contains(from)
     }
 
-    fn init_node(&mut self, n: &String) {
-        self.in_edges.insert(n.clone(), HashSet::new());
-        self.out_edges.insert(n.clone(), vec![]);
+    fn init_node(&mut self, n: &str) {
+        self.in_edges.insert(n.to_string(), HashSet::new());
+        self.out_edges.insert(n.to_string(), vec![]);
     }
 
-    fn add_edge(&mut self, from: &String, to: &String) {
+    fn add_edge(&mut self, from: &str, to: &str) {
         if !self.has_node(to) {
             self.init_node(to);
         }
@@ -150,8 +150,8 @@ impl Graph {
         }
 
         if from != to && !self.has_edge(from, to) {
-            self.in_edges.get_mut(to).unwrap().insert(from.clone());
-            self.out_edges.get_mut(from).unwrap().push(to.clone());
+            self.in_edges.get_mut(to).unwrap().insert(from.to_string());
+            self.out_edges.get_mut(from).unwrap().push(to.to_string());
         }
     }