Fix beta build warnings / errors. (#1603)

Fixes #1598

src/codegen/error.rs

@@ -20,7 +20,7 @@ impl fmt::Display for Error {
 }
 
 impl error::Error for Error {
-    fn cause(&self) -> Option<&error::Error> {
+    fn cause(&self) -> Option<&dyn error::Error> {
         None
     }
 

src/codegen/mod.rs

@@ -742,7 +742,7 @@ impl CodeGenerator for Type {
                     .all(|c| match c {
                         // These are the only characters allowed in simple
                         // paths, eg `good::dogs::Bront`.
-                        'A'...'Z' | 'a'...'z' | '0'...'9' | ':' | '_' | ' ' => true,
+                        'A'..='Z' | 'a'..='z' | '0'..='9' | ':' | '_' | ' ' => true,
                         _ => false,
                     }) &&
                     outer_params.is_empty() &&

src/ir/context.rs

@@ -661,7 +661,7 @@ If you encounter an error missing from this list, please file an issue or a PR!"
     }
 
     /// Get the user-provided callbacks by reference, if any.
-    pub fn parse_callbacks(&self) -> Option<&ParseCallbacks> {
+    pub fn parse_callbacks(&self) -> Option<&dyn ParseCallbacks> {
         self.options().parse_callbacks.as_ref().map(|t| &**t)
     }
 

src/lib.rs

@@ -1146,7 +1146,7 @@ impl Builder {
     /// [`ParseCallbacks`](./callbacks/trait.ParseCallbacks.html) documentation.
     pub fn parse_callbacks(
         mut self,
-        cb: Box<callbacks::ParseCallbacks>,
+        cb: Box<dyn callbacks::ParseCallbacks>,
     ) -> Self {
         self.options.parse_callbacks = Some(cb);
         self
@@ -1500,7 +1500,7 @@ struct BindgenOptions {
 
     /// A user-provided visitor to allow customizing different kinds of
     /// situations.
-    parse_callbacks: Option<Box<callbacks::ParseCallbacks>>,
+    parse_callbacks: Option<Box<dyn callbacks::ParseCallbacks>>,
 
     /// Which kind of items should we generate? By default, we'll generate all
     /// of them.
@@ -1853,7 +1853,7 @@ impl Bindings {
     /// Convert these bindings into source text (with raw lines prepended).
     pub fn to_string(&self) -> String {
         let mut bytes = vec![];
-        self.write(Box::new(&mut bytes) as Box<Write>)
+        self.write(Box::new(&mut bytes) as Box<dyn Write>)
             .expect("writing to a vec cannot fail");
         String::from_utf8(bytes)
             .expect("we should only write bindings that are valid utf-8")
@@ -1871,7 +1871,7 @@ impl Bindings {
     }
 
     /// Write these bindings as source text to the given `Write`able.
-    pub fn write<'a>(&self, mut writer: Box<Write + 'a>) -> io::Result<()> {
+    pub fn write<'a>(&self, mut writer: Box<dyn Write + 'a>) -> io::Result<()> {
         writer.write(
             "/* automatically generated by rust-bindgen */\n\n".as_bytes(),
         )?;

src/options.rs

@@ -8,7 +8,7 @@ use std::str::FromStr;
 /// Construct a new [`Builder`](./struct.Builder.html) from command line flags.
 pub fn builder_from_flags<I>(
     args: I,
-) -> Result<(Builder, Box<io::Write>, bool), io::Error>
+) -> Result<(Builder, Box<dyn io::Write>, bool), io::Error>
 where
     I: Iterator<Item = String>,
 {
@@ -600,9 +600,9 @@ where
 
     let output = if let Some(path) = matches.value_of("output") {
         let file = File::create(path)?;
-        Box::new(io::BufWriter::new(file)) as Box<io::Write>
+        Box::new(io::BufWriter::new(file)) as Box<dyn io::Write>
     } else {
-        Box::new(io::BufWriter::new(io::stdout())) as Box<io::Write>
+        Box::new(io::BufWriter::new(io::stdout())) as Box<dyn io::Write>
     };
 
     if matches.is_present("dump-preprocessed-input") {