Named struct without body is enough

Author: lucic71

cpp2rust/converter/converter.cpp

@@ -53,12 +53,12 @@ use std::rc::Rc;
 )");
 }
 
-std::string Converter::EmitOpaqueRecordMarkers() {
+std::string Converter::EmitOpaqueRecords() {
   std::string out;
   record_decls_.ForEachUndefined([&](const std::string &name) {
-    out += "#[repr(C)] pub struct ";
+    out += "pub struct ";
     out += name;
-    out += " { _opaque: [u8; 0] }\n";
+    out += ";\n";
   });
   return out;
 }

cpp2rust/converter/converter.h

@@ -51,7 +51,7 @@ class Converter : public clang::RecursiveASTVisitor<Converter> {
 
   virtual void EmitFilePreamble();
 
-  static std::string EmitOpaqueRecordMarkers();
+  static std::string EmitOpaqueRecords();
 
   virtual bool VisitBuiltinType(clang::BuiltinType *type);
 

cpp2rust/cpp2rust_lib.cpp

@@ -30,7 +30,7 @@ std::string TranspileSrc(std::string_view cc_code, Model model,
                                        rules_dir),
       cc_code, tool_args, std::filesystem::path(filename).filename().string(),
       filename.ends_with(".c") ? CLANG_C_COMPILER : CLANG_CXX_COMPILER);
-  rs_code += Converter::EmitOpaqueRecordMarkers();
+  rs_code += Converter::EmitOpaqueRecords();
   return rs_code;
 }
 
@@ -70,7 +70,7 @@ std::string TranspileDir(std::string_view build_dir, Model model,
   std::string rs_code;
   FrontendActionFactory factory(rs_code, model, rules_dir);
   Tool.run(&factory);
-  rs_code += Converter::EmitOpaqueRecordMarkers();
+  rs_code += Converter::EmitOpaqueRecords();
   return rs_code;
 }
 } // namespace cpp2rust

tests/multi-file/opaque_forward_decl/out/refcount/opaque_forward_decl.rs

@@ -32,7 +32,4 @@ pub fn touch_0(c: Ptr<container>) {
     let c: Value<Ptr<container>> = Rc::new(RefCell::new(c));
     (*(*(*c.borrow()).upgrade().deref()).p.borrow()).clone();
 }
-#[repr(C)]
-pub struct opaque {
-    _opaque: [u8; 0],
-}
+pub struct opaque;

tests/multi-file/opaque_forward_decl/out/unsafe/opaque_forward_decl.rs

@@ -33,7 +33,4 @@ unsafe fn main_0() -> i32 {
 pub unsafe fn touch_0(mut c: *mut container) {
     &((*c).p);
 }
-#[repr(C)]
-pub struct opaque {
-    _opaque: [u8; 0],
-}
+pub struct opaque;

tests/unit/out/refcount/opaque_forward_decl.rs

@@ -23,7 +23,4 @@ fn main_0() -> i32 {
     (*(*c.borrow()).p.borrow()).clone();
     return ((*(*c.borrow()).x.borrow()) - 42);
 }
-#[repr(C)]
-pub struct opaque {
-    _opaque: [u8; 0],
-}
+pub struct opaque;

tests/unit/out/unsafe/opaque_forward_decl.rs

@@ -25,7 +25,4 @@ unsafe fn main_0() -> i32 {
     &(c.p);
     return ((c.x) - (42));
 }
-#[repr(C)]
-pub struct opaque {
-    _opaque: [u8; 0],
-}
+pub struct opaque;