Auto merge of #889 - photoszzt:fix_recursive_whitelist_opaque, r=fitzgen

Fix recursive whitelisting and handling of opaque for derive default

Fix regression of derive default analysis.
Also fix opaque handing exposed by the above fix. r? @fitzgen

Author: bors-servo

src/ir/analysis/derive_default.rs

@@ -158,7 +158,7 @@ impl<'ctx, 'gen> MonotoneFramework for CannotDeriveDefault<'ctx, 'gen> {
             }
         };
 
-        if ty.is_opaque(self.ctx, item) {
+        if item.is_opaque(self.ctx, &()) {
             let layout_can_derive = ty.layout(self.ctx).map_or(true, |l| {
                 l.opaque().can_trivially_derive_default()
             });
@@ -265,7 +265,8 @@ impl<'ctx, 'gen> MonotoneFramework for CannotDeriveDefault<'ctx, 'gen> {
 
                 let bases_cannot_derive = info.base_members()
                     .iter()
-                    .any(|base| self.cannot_derive_default.contains(&base.ty));
+                    .any(|base| !self.ctx.whitelisted_items().contains(&base.ty) ||
+                         self.cannot_derive_default.contains(&base.ty));
                 if bases_cannot_derive {
                     trace!("    base members cannot derive Default, so we can't \
                             either");
@@ -277,12 +278,14 @@ impl<'ctx, 'gen> MonotoneFramework for CannotDeriveDefault<'ctx, 'gen> {
                     .any(|f| {
                         match *f {
                             Field::DataMember(ref data) => {
-                                self.cannot_derive_default.contains(&data.ty())
+                                !self.ctx.whitelisted_items().contains(&data.ty()) ||
+                                    self.cannot_derive_default.contains(&data.ty())
                             }
                             Field::Bitfields(ref bfu) => {
                                 bfu.bitfields()
                                     .iter().any(|b| {
-                                        self.cannot_derive_default.contains(&b.ty())
+                                        !self.ctx.whitelisted_items().contains(&b.ty()) ||
+                                            self.cannot_derive_default.contains(&b.ty())
                                     })
                             }
                         }

tests/expectations/tests/no-derive-debug.rs

@@ -9,7 +9,7 @@
 /// and replacement for another type that doesn't implement it would prevent it
 /// from building if --no-derive-debug didn't work.
 #[repr(C)]
-#[derive(Default, Copy)]
+#[derive(Copy)]
 pub struct bar {
     pub foo: foo,
     pub baz: ::std::os::raw::c_int,
@@ -34,3 +34,6 @@ fn bindgen_test_layout_bar() {
 impl Clone for bar {
     fn clone(&self) -> Self { *self }
 }
+impl Default for bar {
+    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
+}

tests/expectations/tests/no-recursive-whitelisting.rs

@@ -6,7 +6,7 @@
 pub enum Bar {}
 
 #[repr(C)]
-#[derive(Debug, Default, Copy)]
+#[derive(Debug, Copy)]
 pub struct Foo {
     pub baz: *mut Bar,
 }
@@ -25,3 +25,6 @@ fn bindgen_test_layout_Foo() {
 impl Clone for Foo {
     fn clone(&self) -> Self { *self }
 }
+impl Default for Foo {
+    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
+}

tests/expectations/tests/opaque-template-inst-member-2.rs

@@ -5,12 +5,9 @@
 
 
 #[repr(C)]
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug, Default, Copy, Clone)]
 pub struct OpaqueTemplate {
 }
-impl Default for OpaqueTemplate {
-    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
-}
 #[repr(C)]
 #[derive(Debug, Default, Copy)]
 pub struct ContainsOpaqueTemplate {

tests/expectations/tests/opaque-template-inst-member.rs

@@ -5,12 +5,9 @@
 
 
 #[repr(C)]
-#[derive(Copy, Clone)]
+#[derive(Default, Copy, Clone)]
 pub struct OpaqueTemplate {
 }
-impl Default for OpaqueTemplate {
-    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
-}
 #[repr(C)]
 pub struct ContainsOpaqueTemplate {
     pub mBlah: [u32; 101usize],

tests/expectations/tests/opaque_pointer.rs

@@ -22,12 +22,9 @@ impl Clone for OtherOpaque {
 }
 /// <div rustbindgen opaque></div>
 #[repr(C)]
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug, Default, Copy, Clone)]
 pub struct Opaque {
 }
-impl Default for Opaque {
-    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
-}
 #[repr(C)]
 #[derive(Debug, Copy)]
 pub struct WithOpaquePtr {

tests/expectations/tests/template.rs

@@ -171,12 +171,9 @@ impl Default for PODButContainsDtor {
 }
 /// <div rustbindgen opaque>
 #[repr(C)]
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug, Default, Copy, Clone)]
 pub struct Opaque {
 }
-impl Default for Opaque {
-    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
-}
 #[repr(C)]
 #[derive(Debug, Default, Copy)]
 pub struct POD {