Auto merge of #367 - emilio:auto-redux, r=upsuper

ir: More generic handling of non-deductible auto types.

Also, merge auto-related tests in `auto.hpp`.

r? @upsuper

Author: bors-servo

libbindgen/src/ir/comp.rs

@@ -748,9 +748,9 @@ impl CompInfo {
                         return CXChildVisit_Continue;
                     }
 
-                    let item = Item::parse(cur, Some(potential_id), ctx)
-                        .expect("VarDecl");
-                    ci.inner_vars.push(item);
+                    if let Ok(item) = Item::parse(cur, Some(potential_id), ctx) {
+                        ci.inner_vars.push(item);
+                    }
                 }
                 // Intentionally not handled
                 CXCursor_CXXAccessSpecifier |

libbindgen/src/ir/ty.rs

@@ -776,8 +776,11 @@ impl Type {
                 }
             }
             CXType_Auto => {
-                // We don't want to blow the stack.
-                assert!(canonical_ty != *ty, "Couldn't find deduced type");
+                if canonical_ty == *ty {
+                    debug!("Couldn't find deduced type: {:?}", ty);
+                    return Err(ParseError::Continue);
+                }
+
                 return Self::from_clang_ty(potential_id,
                                            &canonical_ty,
                                            location,

libbindgen/src/ir/var.rs

@@ -186,8 +186,15 @@ impl ClangSubItemParser for Var {
                 // XXX this is redundant, remove!
                 let is_const = ty.is_const();
 
-                let ty = Item::from_ty(&ty, Some(cursor), None, ctx)
-                    .expect("Unable to resolve constant type?");
+                let ty = match Item::from_ty(&ty, Some(cursor), None, ctx) {
+                    Ok(ty) => ty,
+                    Err(e) => {
+                        assert_eq!(ty.kind(), CXType_Auto,
+                                   "Couldn't resolve constant type, and it \
+                                   wasn't an nondeductible auto type!");
+                        return Err(e);
+                    }
+                };
 
                 // Note: Ty might not be totally resolved yet, see
                 // tests/headers/inner_const.hpp

libbindgen/tests/expectations/tests/auto.rs

@@ -9,7 +9,7 @@
 pub struct Foo {
     pub _address: u8,
 }
-pub const Foo_kBar: bool = true;
+pub const Foo_kFoo: bool = true;
 #[test]
 fn bindgen_test_layout_Foo() {
     assert_eq!(::std::mem::size_of::<Foo>() , 1usize);
@@ -18,3 +18,13 @@ fn bindgen_test_layout_Foo() {
 impl Clone for Foo {
     fn clone(&self) -> Self { *self }
 }
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct Bar<T> {
+    pub _address: u8,
+    pub _phantom_0: ::std::marker::PhantomData<T>,
+}
+extern "C" {
+    #[link_name = "_Z5Test2v"]
+    pub fn Test2() -> ::std::os::raw::c_uint;
+}

libbindgen/tests/expectations/tests/template_function_with_auto.rs

@@ -1,6 +1,19 @@
-// bindgen-flags: -- -std=c++11
+// bindgen-flags: -- -std=c++14
 // bindgen-unstable
 
 class Foo {
-  static constexpr auto kBar = 2 == 2;
+  static constexpr auto kFoo = 2 == 2;
 };
+
+template<typename T>
+class Bar {
+  static const constexpr auto kBar = T(1);
+};
+
+template<typename T> auto Test1() {
+  return T(1);
+}
+
+auto Test2() {
+  return Test1<unsigned int>();
+}