codegen: Add an option to skip comment generation.

This is mostly a work around rust-lang#426,
until we implement the proper fix.

Author: emilio

Cargo.toml

@@ -13,7 +13,7 @@ name = "bindgen"
 readme = "README.md"
 repository = "https://github.com/servo/rust-bindgen"
 documentation = "https://docs.rs/bindgen"
-version = "0.20.2"
+version = "0.20.3"
 build = "build.rs"
 
 [badges]

src/codegen/mod.rs

@@ -534,8 +534,10 @@ impl CodeGenerator for Type {
                 let rust_name = ctx.rust_ident(&name);
                 let mut typedef = aster::AstBuilder::new().item().pub_();
 
-                if let Some(comment) = item.comment() {
-                    typedef = typedef.attr().doc(comment);
+                if ctx.options().generate_comments {
+                    if let Some(comment) = item.comment() {
+                        typedef = typedef.attr().doc(comment);
+                    }
                 }
 
                 // We prefer using `pub use` over `pub type` because of:
@@ -808,8 +810,10 @@ impl CodeGenerator for CompInfo {
 
         let mut attributes = vec![];
         let mut needs_clone_impl = false;
-        if let Some(comment) = item.comment() {
-            attributes.push(attributes::doc(comment));
+        if ctx.options().generate_comments {
+            if let Some(comment) = item.comment() {
+                attributes.push(attributes::doc(comment));
+            }
         }
         if self.packed() {
             attributes.push(attributes::repr_list(&["C", "packed"]));
@@ -1007,8 +1011,10 @@ impl CodeGenerator for CompInfo {
             };
 
             let mut attrs = vec![];
-            if let Some(comment) = field.comment() {
-                attrs.push(attributes::doc(comment));
+            if ctx.options().generate_comments {
+                if let Some(comment) = field.comment() {
+                    attrs.push(attributes::doc(comment));
+                }
             }
             let field_name = match field.name() {
                 Some(name) => ctx.rust_mangle(name).into_owned(),
@@ -1705,8 +1711,10 @@ impl CodeGenerator for Enum {
             builder = builder.with_attr(attributes::repr("C"));
         }
 
-        if let Some(comment) = item.comment() {
-            builder = builder.with_attr(attributes::doc(comment));
+        if ctx.options().generate_comments {
+            if let Some(comment) = item.comment() {
+                builder = builder.with_attr(attributes::doc(comment));
+            }
         }
 
         if !is_constified_enum {
@@ -2166,8 +2174,10 @@ impl CodeGenerator for Function {
 
         let mut attributes = vec![];
 
-        if let Some(comment) = item.comment() {
-            attributes.push(attributes::doc(comment));
+        if ctx.options().generate_comments {
+            if let Some(comment) = item.comment() {
+                attributes.push(attributes::doc(comment));
+            }
         }
 
         if let Some(mangled) = mangled_name {

src/lib.rs

@@ -175,6 +175,19 @@ impl Builder {
         self
     }
 
+    /// Whether the generated bindings should contain documentation comments or
+    /// not.
+    ///
+    /// This ideally will always be true, but it may need to be false until we
+    /// implement some processing on comments to work around issues as described
+    /// in:
+    ///
+    /// https://github.com/servo/rust-bindgen/issues/426
+    pub fn generate_comments(mut self, doit: bool) -> Self {
+        self.options.generate_comments = doit;
+        self
+    }
+
     /// Generate a C/C++ file that includes the header and has dummy uses of
     /// every type defined in the header.
     pub fn dummy_uses<T: Into<String>>(mut self, dummy_uses: T) -> Builder {
@@ -495,6 +508,7 @@ pub struct BindgenOptions {
     /// The input header file.
     pub input_header: Option<String>,
 
+
     /// Generate a dummy C/C++ file that includes the header and has dummy uses
     /// of all types defined therein. See the `uses` module for more.
     pub dummy_uses: Option<String>,
@@ -511,6 +525,10 @@ pub struct BindgenOptions {
     ///
     /// See the builder method description for more details.
     pub conservative_inline_namespaces: bool,
+
+    /// Wether to keep documentation comments in the generated output. See the
+    /// documentation for more details.
+    pub generate_comments: bool,
 }
 
 impl BindgenOptions {
@@ -555,6 +573,7 @@ impl Default for BindgenOptions {
             type_chooser: None,
             codegen_config: CodegenConfig::all(),
             conservative_inline_namespaces: false,
+            generate_comments: true,
         }
     }
 }

src/options.rs

@@ -42,6 +42,10 @@ pub fn builder_from_flags<I>(args: I)
             Arg::with_name("no-derive-debug")
                 .long("no-derive-debug")
                 .help("Avoid deriving Debug on any type."),
+            Arg::with_name("no-doc-comments")
+                .long("no-doc-comments")
+                .help("Avoid including doc comments in the output, see: \
+                      https://github.com/servo/rust-bindgen/issues/426"),
             Arg::with_name("builtins")
                 .long("builtins")
                 .help("Output bindings for builtin definitions, e.g. \
@@ -271,6 +275,10 @@ pub fn builder_from_flags<I>(args: I)
         builder = builder.no_convert_floats();
     }
 
+    if matches.is_present("no-doc-comments") {
+        builder = builder.generate_comments(false);
+    }
+
     if let Some(opaque_types) = matches.values_of("opaque-type") {
         for ty in opaque_types {
             builder = builder.opaque_type(ty);

tests/expectations/tests/no-comments.rs

@@ -0,0 +1,19 @@
+/* automatically generated by rust-bindgen */
+
+
+#![allow(non_snake_case)]
+
+
+#[repr(C)]
+#[derive(Debug, Copy)]
+pub struct Foo {
+    pub s: ::std::os::raw::c_int,
+}
+#[test]
+fn bindgen_test_layout_Foo() {
+    assert_eq!(::std::mem::size_of::<Foo>() , 4usize);
+    assert_eq!(::std::mem::align_of::<Foo>() , 4usize);
+}
+impl Clone for Foo {
+    fn clone(&self) -> Self { *self }
+}

tests/headers/no-comments.h

@@ -0,0 +1,5 @@
+// bindgen-flags: --no-doc-comments
+
+struct Foo {
+    int s; /*!< Including this will prevent rustc for compiling it */
+};