Derive Default for function pointers

Author: Jethro Beekman

src/ir/analysis/derive.rs

@@ -194,11 +194,7 @@ impl<'ctx> CannotDerive<'ctx> {
                 let inner_type =
                     self.ctx.resolve_type(inner).canonical_type(self.ctx);
                 if let TypeKind::Function(ref sig) = *inner_type.kind() {
-                    if let DeriveTrait::Default = self.derive_trait {
-                        return CanDerive::No
-                    } else {
-                        return self.derive_trait.can_derive_fnptr(sig)
-                    }
+                    return self.derive_trait.can_derive_fnptr(sig)
                 } else {
                     return self.derive_trait.can_derive_pointer();
                 }

tests/expectations/tests/derive-fn-ptr.rs

@@ -1,8 +1,11 @@
 /* automatically generated by rust-bindgen */
 
-
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
-
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 pub type my_fun_t = ::std::option::Option<
     unsafe extern "C" fn(
@@ -25,7 +28,7 @@ pub type my_fun_t = ::std::option::Option<
     ),
 >;
 #[repr(C)]
-#[derive(Copy, Clone)]
+#[derive(Default, Copy, Clone)]
 pub struct Foo {
     pub callback: my_fun_t,
 }
@@ -52,11 +55,6 @@ fn bindgen_test_layout_Foo() {
         )
     );
 }
-impl Default for Foo {
-    fn default() -> Self {
-        unsafe { ::std::mem::zeroed() }
-    }
-}
 pub type my_fun2_t = ::std::option::Option<
     unsafe extern "C" fn(
         arg1: ::std::os::raw::c_int,
@@ -74,7 +72,7 @@ pub type my_fun2_t = ::std::option::Option<
     ),
 >;
 #[repr(C)]
-#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
+#[derive(Debug, Default, Copy, Clone, Hash, PartialEq, Eq)]
 pub struct Bar {
     pub callback: my_fun2_t,
 }
@@ -101,8 +99,3 @@ fn bindgen_test_layout_Bar() {
         )
     );
 }
-impl Default for Bar {
-    fn default() -> Self {
-        unsafe { ::std::mem::zeroed() }
-    }
-}

tests/expectations/tests/func_ptr_in_struct.rs

@@ -1,14 +1,19 @@
 /* automatically generated by rust-bindgen */
 
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 #[repr(i32)]
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 pub enum baz {
     __bindgen_cannot_repr_c_on_empty_enum = 0,
 }
 #[repr(C)]
-#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
+#[derive(Debug, Default, Copy, Clone, Hash, PartialEq, Eq)]
 pub struct Foo {
     pub bar: ::std::option::Option<
         unsafe extern "C" fn(x: ::std::os::raw::c_int, y: ::std::os::raw::c_int) -> baz,
@@ -32,8 +37,3 @@ fn bindgen_test_layout_Foo() {
         concat!("Offset of field: ", stringify!(Foo), "::", stringify!(bar))
     );
 }
-impl Default for Foo {
-    fn default() -> Self {
-        unsafe { ::std::mem::zeroed() }
-    }
-}

tests/expectations/tests/issue-1216-variadic-member.rs

@@ -1,12 +1,17 @@
 /* automatically generated by rust-bindgen */
 
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 extern "C" {
     pub fn f(a: ::std::os::raw::c_int, ...);
 }
 #[repr(C)]
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug, Default, Copy, Clone)]
 pub struct Foo {
     pub f: ::std::option::Option<
         unsafe extern "C" fn(
@@ -35,8 +40,3 @@ fn bindgen_test_layout_Foo() {
         concat!("Offset of field: ", stringify!(Foo), "::", stringify!(f))
     );
 }
-impl Default for Foo {
-    fn default() -> Self {
-        unsafe { ::std::mem::zeroed() }
-    }
-}

tests/expectations/tests/layout_cmdline_token.rs

@@ -72,7 +72,7 @@ pub type cmdline_parse_token_hdr_t = cmdline_token_hdr;
 /// get_help() fills the dstbuf with the help for the token. It returns
 /// -1 on error and 0 on success.
 #[repr(C)]
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug, Default, Copy, Clone)]
 pub struct cmdline_token_ops {
     /// parse(token ptr, buf, res pts, buf len)
     pub parse: ::std::option::Option<
@@ -162,11 +162,6 @@ fn bindgen_test_layout_cmdline_token_ops() {
         )
     );
 }
-impl Default for cmdline_token_ops {
-    fn default() -> Self {
-        unsafe { ::std::mem::zeroed() }
-    }
-}
 #[repr(u32)]
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 pub enum cmdline_numtype {

tests/expectations/tests/libclang-3.8/call-conv-field.rs

@@ -1,16 +1,18 @@
 /* automatically generated by rust-bindgen */
 
-
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 #![cfg(not(test))]
 
-
 #[repr(C)]
-#[derive(Copy, Clone)]
+#[derive(Default, Copy, Clone)]
 pub struct JNINativeInterface_ {
     pub GetVersion: ::std::option::Option<
-        unsafe extern "stdcall" fn(env: *mut ::std::os::raw::c_void)
-            -> ::std::os::raw::c_int,
+        unsafe extern "stdcall" fn(env: *mut ::std::os::raw::c_void) -> ::std::os::raw::c_int,
     >,
     pub __hack: ::std::os::raw::c_ulonglong,
 }
@@ -47,11 +49,6 @@ fn bindgen_test_layout_JNINativeInterface_() {
         )
     );
 }
-impl Default for JNINativeInterface_ {
-    fn default() -> Self {
-        unsafe { ::std::mem::zeroed() }
-    }
-}
 extern "C" {
     #[link_name = "\u{1}_bar@0"]
     pub fn bar();

tests/expectations/tests/libclang-3.9/call-conv-field.rs

@@ -6,7 +6,7 @@
 
 
 #[repr(C)]
-#[derive(Copy, Clone)]
+#[derive(Default, Copy, Clone)]
 pub struct JNINativeInterface_ {
     pub GetVersion: ::std::option::Option<
         unsafe extern "stdcall" fn(env: *mut ::std::os::raw::c_void)
@@ -47,11 +47,6 @@ fn bindgen_test_layout_JNINativeInterface_() {
         )
     );
 }
-impl Default for JNINativeInterface_ {
-    fn default() -> Self {
-        unsafe { ::std::mem::zeroed() }
-    }
-}
 extern "stdcall" {
     #[link_name = "\u{1}_bar@0"]
     pub fn bar();

tests/expectations/tests/libclang-4/call-conv-field.rs

@@ -6,7 +6,7 @@
 
 
 #[repr(C)]
-#[derive(Copy, Clone)]
+#[derive(Default, Copy, Clone)]
 pub struct JNINativeInterface_ {
     pub GetVersion: ::std::option::Option<
         unsafe extern "stdcall" fn(env: *mut ::std::os::raw::c_void)
@@ -47,11 +47,6 @@ fn bindgen_test_layout_JNINativeInterface_() {
         )
     );
 }
-impl Default for JNINativeInterface_ {
-    fn default() -> Self {
-        unsafe { ::std::mem::zeroed() }
-    }
-}
 extern "stdcall" {
     #[link_name = "\u{1}_bar@0"]
     pub fn bar();

tests/expectations/tests/libclang-5/call-conv-field.rs

@@ -9,7 +9,7 @@
 #![cfg(not(test))]
 
 #[repr(C)]
-#[derive(Copy, Clone)]
+#[derive(Default, Copy, Clone)]
 pub struct JNINativeInterface_ {
     pub GetVersion: ::std::option::Option<
         unsafe extern "stdcall" fn(env: *mut ::std::os::raw::c_void) -> ::std::os::raw::c_int,
@@ -50,11 +50,6 @@ fn bindgen_test_layout_JNINativeInterface_() {
         )
     );
 }
-impl Default for JNINativeInterface_ {
-    fn default() -> Self {
-        unsafe { ::std::mem::zeroed() }
-    }
-}
 extern "stdcall" {
     #[link_name = "\u{1}_bar@0"]
     pub fn bar();