From 0dca34e1191b59795023ea7ddc0ca7119098adf0 Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Wed, 24 Jun 2026 11:32:53 +0100
Subject: [PATCH 01/15] Use C size when size_of diverges between C and Rust

---
 cpp2rust/converter/converter_lib.cpp          | 36 +++++++++++++++++++
 cpp2rust/converter/converter_lib.h            |  4 +++
 .../converter/models/converter_refcount.cpp   | 14 ++++++++
 .../converter/models/converter_refcount.h     |  3 ++
 4 files changed, 57 insertions(+)

diff --git a/cpp2rust/converter/converter_lib.cpp b/cpp2rust/converter/converter_lib.cpp
index 43e380f1..4c4901a4 100644
--- a/cpp2rust/converter/converter_lib.cpp
+++ b/cpp2rust/converter/converter_lib.cpp
@@ -200,6 +200,42 @@ bool IsMut(clang::QualType qual_type) {
            qual_type->getPointeeType().isConstQualified());
 }
 
+bool TypeImplementsByteRepr(clang::QualType qt) {
+  if (qt->isEnumeralType()) {
+    return false;
+  }
+  if (qt->isIntegerType() || qt->isFloatingType()) {
+    return true;
+  }
+  if (const auto *arr = qt->getAsArrayTypeUnsafe()) {
+    return TypeImplementsByteRepr(arr->getElementType());
+  }
+  if (const auto *rd = qt->getAsRecordDecl()) {
+    if (rd->isUnion()) {
+      return true;
+    }
+    for (const auto *field : rd->fields()) {
+      if (!TypeImplementsByteRepr(field->getType())) {
+        return false;
+      }
+    }
+    return true;
+  }
+  return false;
+}
+
+bool RustSizeDivergesFromC(clang::QualType qt) {
+  qt = qt.getCanonicalType();
+  // Records have Rc<RefCell<>> fields that diverge from the C size
+  if (qt->isRecordType()) {
+    return true;
+  }
+  if (auto *arr = qt->getAsArrayTypeUnsafe()) {
+    return RustSizeDivergesFromC(arr->getElementType());
+  }
+  return false;
+}
+
 bool IsMutatingCall(const clang::CallExpr *expr) {
   if (auto *callee = expr->getDirectCallee()) {
     if (auto *method = clang::dyn_cast<clang::CXXMethodDecl>(callee)) {
diff --git a/cpp2rust/converter/converter_lib.h b/cpp2rust/converter/converter_lib.h
index 25c84210..d652735e 100644
--- a/cpp2rust/converter/converter_lib.h
+++ b/cpp2rust/converter/converter_lib.h
@@ -52,6 +52,10 @@ bool IsUnsignedArithOp(const clang::BinaryOperator *expr);
 
 bool IsMut(clang::QualType qual_type);
 
+bool TypeImplementsByteRepr(clang::QualType qt);
+
+bool RustSizeDivergesFromC(clang::QualType qt);
+
 bool IsMutatingCall(const clang::CallExpr *expr);
 
 bool IsOverloadedFunction(const clang::FunctionDecl *decl);
diff --git a/cpp2rust/converter/models/converter_refcount.cpp b/cpp2rust/converter/models/converter_refcount.cpp
index eb89d496..b167b26a 100644
--- a/cpp2rust/converter/models/converter_refcount.cpp
+++ b/cpp2rust/converter/models/converter_refcount.cpp
@@ -1322,6 +1322,20 @@ bool ConverterRefCount::VisitExplicitCastExpr(clang::ExplicitCastExpr *expr) {
   }
 }
 
+bool ConverterRefCount::VisitUnaryExprOrTypeTraitExpr(
+    clang::UnaryExprOrTypeTraitExpr *expr) {
+  if (expr->getKind() == clang::UnaryExprOrTypeTrait::UETT_SizeOf) {
+    auto arg_type = expr->isArgumentType() ? expr->getArgumentType()
+                                           : expr->getArgumentExpr()->getType();
+    if (RustSizeDivergesFromC(arg_type)) {
+      StrCat(std::format("{}usize", ctx_.getTypeSize(arg_type) / 8));
+      computed_expr_type_ = ComputedExprType::FreshValue;
+      return false;
+    }
+  }
+  return Converter::VisitUnaryExprOrTypeTraitExpr(expr);
+}
+
 bool ConverterRefCount::VisitStmtExpr(clang::StmtExpr *expr) {
   PushConversionKind push(*this, ConversionKind::FullRefCount);
   return Converter::VisitStmtExpr(expr);
diff --git a/cpp2rust/converter/models/converter_refcount.h b/cpp2rust/converter/models/converter_refcount.h
index 1a3634a3..7737a244 100644
--- a/cpp2rust/converter/models/converter_refcount.h
+++ b/cpp2rust/converter/models/converter_refcount.h
@@ -43,6 +43,9 @@ class ConverterRefCount final : public Converter {
 
   void AddByteReprTrait(const clang::EnumDecl *decl) override;
 
+  bool
+  VisitUnaryExprOrTypeTraitExpr(clang::UnaryExprOrTypeTraitExpr *expr) override;
+
   void AddDefaultTrait(const clang::RecordDecl *decl) override;
 
   void AddDefaultTraitForUnion(const clang::RecordDecl *decl) override;

From 8fa8bec3c0789d0ddbd21b11ac1f7dc1afcce18e Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Wed, 24 Jun 2026 11:34:07 +0100
Subject: [PATCH 02/15] Add byte_size in ByteRepr to capture C size

---
 .../converter/models/converter_refcount.cpp   |  6 +-
 libcc2rs/src/rc.rs                            | 97 +++++++++++--------
 libcc2rs/src/reinterpret.rs                   | 14 ++-
 3 files changed, 69 insertions(+), 48 deletions(-)

diff --git a/cpp2rust/converter/models/converter_refcount.cpp b/cpp2rust/converter/models/converter_refcount.cpp
index b167b26a..d104e4b9 100644
--- a/cpp2rust/converter/models/converter_refcount.cpp
+++ b/cpp2rust/converter/models/converter_refcount.cpp
@@ -566,7 +566,8 @@ static bool recordImplementsByteRepr(const clang::RecordDecl *decl) {
 void ConverterRefCount::AddByteReprTrait(const clang::RecordDecl *decl) {
   auto struct_name = GetRecordName(decl);
 
-  if (!recordImplementsByteRepr(decl)) {
+
+  if (!TypeImplementsByteRepr(ctx_.getCanonicalTagType(decl))) {
     StrCat(std::format("impl ByteRepr for {}", struct_name));
     PushBrace brace(*this);
     return;
@@ -577,6 +578,9 @@ void ConverterRefCount::AddByteReprTrait(const clang::RecordDecl *decl) {
 
   const auto &layout = ctx_.getASTRecordLayout(decl);
 
+  StrCat(std::format("fn byte_size() -> usize {{ {} }}",
+                     ctx_.getTypeSize(ctx_.getCanonicalTagType(decl)) / 8));
+
   StrCat("fn to_bytes(&self, buf: &mut [u8])");
   {
     PushBrace fn_brace(*this);
diff --git a/libcc2rs/src/rc.rs b/libcc2rs/src/rc.rs
index ccf2f991..6a643d6f 100644
--- a/libcc2rs/src/rc.rs
+++ b/libcc2rs/src/rc.rs
@@ -16,6 +16,13 @@ use crate::reinterpret::{ByteRepr, OriginalAlloc, SingleOriginalAlloc, SliceOrig
 
 pub type Value<T> = Rc<RefCell<T>>;
 
+struct ReinterpretedView {
+    // Pointer to the source of reinterpret
+    alloc: Rc<dyn OriginalAlloc>,
+    // C++ size of the reinterpreted view
+    elem_byte_size: usize,
+}
+
 #[derive(Default)]
 enum PtrKind<T> {
     #[default]
@@ -25,7 +32,7 @@ enum PtrKind<T> {
     HeapSingle(Weak<RefCell<T>>),
     HeapArray(Weak<RefCell<Box<[T]>>>),
     Vec(Weak<RefCell<Vec<T>>>),
-    Reinterpreted(Rc<dyn OriginalAlloc>),
+    Reinterpreted(Rc<ReinterpretedView>),
 }
 
 pub enum StrongPtr<T> {
@@ -59,7 +66,7 @@ impl<T: ByteRepr> StrongPtr<T> {
                 cell,
             } => {
                 // Read-through: always re-read from the original allocation.
-                let mut buf = vec![0u8; std::mem::size_of::<T>()];
+                let mut buf = vec![0u8; T::byte_size()];
                 alloc.read_bytes(*byte_offset, &mut buf);
                 *cell.borrow_mut() = Some(T::from_bytes(&buf));
                 Ref::map(cell.borrow(), |opt| opt.as_ref().unwrap())
@@ -77,8 +84,8 @@ impl<T> fmt::Debug for PtrKind<T> {
             PtrKind::HeapSingle(w) => write!(f, "HeapSingle({:?})", w.as_ptr()),
             PtrKind::StackArray(w) => write!(f, "StackArray({:?})", w.as_ptr()),
             PtrKind::HeapArray(w) => write!(f, "HeapArray({:?})", w.as_ptr()),
-            PtrKind::Reinterpreted(data) => {
-                write!(f, "Reinterpreted(0x{:x})", data.address())
+            PtrKind::Reinterpreted(view) => {
+                write!(f, "Reinterpreted(0x{:x})", view.alloc.address())
             }
         }
     }
@@ -93,7 +100,7 @@ impl<T> Clone for PtrKind<T> {
             PtrKind::HeapSingle(weak) => PtrKind::HeapSingle(weak.clone()),
             PtrKind::StackArray(weak) => PtrKind::StackArray(weak.clone()),
             PtrKind::HeapArray(weak) => PtrKind::HeapArray(weak.clone()),
-            PtrKind::Reinterpreted(data) => PtrKind::Reinterpreted(Rc::clone(data)),
+            PtrKind::Reinterpreted(view) => PtrKind::Reinterpreted(Rc::clone(view)),
         }
     }
 }
@@ -105,7 +112,7 @@ impl<T> PtrKind<T> {
             PtrKind::StackSingle(w) | PtrKind::HeapSingle(w) => w.as_ptr() as usize,
             PtrKind::Vec(w) => w.as_ptr() as usize,
             PtrKind::StackArray(w) | PtrKind::HeapArray(w) => w.as_ptr() as usize,
-            PtrKind::Reinterpreted(data) => data.address(),
+            PtrKind::Reinterpreted(view) => view.alloc.address(),
         }
     }
 }
@@ -251,40 +258,40 @@ impl<T> Ptr<T> {
     #[inline]
     fn elem_step(&self) -> usize {
         match &self.kind {
-            PtrKind::Reinterpreted(_) => std::mem::size_of::<T>(),
+            PtrKind::Reinterpreted(view) => view.elem_byte_size,
             _ => 1,
         }
     }
 
     #[inline]
     pub fn len(&self) -> usize {
-        match self.kind {
+        match &self.kind {
             PtrKind::Null => 0,
             PtrKind::StackSingle(_) | PtrKind::HeapSingle(_) => 1,
-            PtrKind::Vec(ref weak) => weak.upgrade().expect("ub: dangling pointer").borrow().len(),
-            PtrKind::StackArray(ref weak) | PtrKind::HeapArray(ref weak) => {
+            PtrKind::Vec(weak) => weak.upgrade().expect("ub: dangling pointer").borrow().len(),
+            PtrKind::StackArray(weak) | PtrKind::HeapArray(weak) => {
                 weak.upgrade().expect("ub: dangling pointer").borrow().len()
             }
-            PtrKind::Reinterpreted(ref data) => data.total_byte_len() / std::mem::size_of::<T>(),
+            PtrKind::Reinterpreted(view) => view.alloc.total_byte_len() / view.elem_byte_size,
         }
     }
 
     #[inline]
     pub fn is_empty(&self) -> bool {
-        match self.kind {
+        match &self.kind {
             PtrKind::Null => true,
             PtrKind::StackSingle(_) | PtrKind::HeapSingle(_) => false,
-            PtrKind::Vec(ref weak) => weak
+            PtrKind::Vec(weak) => weak
                 .upgrade()
                 .expect("ub: dangling pointer")
                 .borrow()
                 .is_empty(),
-            PtrKind::StackArray(ref weak) | PtrKind::HeapArray(ref weak) => weak
+            PtrKind::StackArray(weak) | PtrKind::HeapArray(weak) => weak
                 .upgrade()
                 .expect("ub: dangling pointer")
                 .borrow()
                 .is_empty(),
-            PtrKind::Reinterpreted(ref data) => self.offset >= data.total_byte_len(),
+            PtrKind::Reinterpreted(view) => self.offset >= view.alloc.total_byte_len(),
         }
     }
 
@@ -339,8 +346,8 @@ impl<T> Ptr<T> {
                 rc: weak.upgrade().expect("ub: dangling pointer"),
                 offset: self.offset,
             },
-            PtrKind::Reinterpreted(data) => StrongPtr::Reinterpreted {
-                alloc: Rc::clone(data),
+            PtrKind::Reinterpreted(view) => StrongPtr::Reinterpreted {
+                alloc: Rc::clone(&view.alloc),
                 byte_offset: self.offset,
                 cell: RefCell::new(None),
             },
@@ -365,10 +372,10 @@ impl<T> Ptr<T> {
                 let rc = weak.upgrade().expect("ub: dangling pointer");
                 rc.borrow_mut()[self.offset] = value;
             }
-            PtrKind::Reinterpreted(data) => {
-                let mut buf = vec![0u8; std::mem::size_of::<T>()];
+            PtrKind::Reinterpreted(view) => {
+                let mut buf = vec![0u8; T::byte_size()];
                 value.to_bytes(&mut buf);
-                data.write_bytes(self.offset, &buf);
+                view.alloc.write_bytes(self.offset, &buf);
             }
         }
     }
@@ -391,30 +398,34 @@ impl<T> Ptr<T> {
             return self_any.downcast_ref::<Ptr<U>>().unwrap().clone();
         }
 
-        if std::mem::size_of::<U>() == 0 {
+        if U::byte_size() == 0 {
             panic!("cannot reinterpret_cast to zero-sized type");
         }
 
+        let src_byte_off = self.offset.wrapping_mul(T::byte_size());
         let (alloc, abs_byte_off): (Rc<dyn OriginalAlloc>, usize) = match &self.kind {
             PtrKind::Null => return Ptr::null(),
             PtrKind::StackSingle(weak) | PtrKind::HeapSingle(weak) => (
                 Rc::new(SingleOriginalAlloc { weak: weak.clone() }),
-                self.byte_offset(),
+                src_byte_off,
             ),
             PtrKind::Vec(weak) => (
                 Rc::new(SliceOriginalAlloc { weak: weak.clone() }),
-                self.byte_offset(),
+                src_byte_off,
             ),
             PtrKind::StackArray(weak) | PtrKind::HeapArray(weak) => (
                 Rc::new(SliceOriginalAlloc { weak: weak.clone() }),
-                self.byte_offset(),
+                src_byte_off,
             ),
-            PtrKind::Reinterpreted(data) => (Rc::clone(data), self.offset),
+            PtrKind::Reinterpreted(view) => (Rc::clone(&view.alloc), self.offset),
         };
 
         Ptr {
             offset: abs_byte_off,
-            kind: PtrKind::Reinterpreted(alloc),
+            kind: PtrKind::Reinterpreted(Rc::new(ReinterpretedView {
+                alloc,
+                elem_byte_size: U::byte_size(),
+            })),
         }
     }
 }
@@ -441,13 +452,13 @@ impl<T> Ptr<T> {
                 let mut borrow = rc.borrow_mut();
                 f(&mut borrow[self.offset])
             }
-            PtrKind::Reinterpreted(data) => {
-                let mut buf = vec![0u8; std::mem::size_of::<T>()];
-                data.read_bytes(self.offset, &mut buf);
+            PtrKind::Reinterpreted(view) => {
+                let mut buf = vec![0u8; T::byte_size()];
+                view.alloc.read_bytes(self.offset, &mut buf);
                 let mut val = T::from_bytes(&buf);
                 let ret = f(&mut val);
                 val.to_bytes(&mut buf);
-                data.write_bytes(self.offset, &buf);
+                view.alloc.write_bytes(self.offset, &buf);
                 ret
             }
         }
@@ -474,9 +485,9 @@ impl<T> Ptr<T> {
                 let borrow = rc.borrow();
                 f(&borrow[self.offset])
             }
-            PtrKind::Reinterpreted(data) => {
-                let mut buf = vec![0u8; std::mem::size_of::<T>()];
-                data.read_bytes(self.offset, &mut buf);
+            PtrKind::Reinterpreted(view) => {
+                let mut buf = vec![0u8; T::byte_size()];
+                view.alloc.read_bytes(self.offset, &mut buf);
                 let val = T::from_bytes(&buf);
                 f(&val)
             }
@@ -501,9 +512,9 @@ impl<T: Clone + ByteRepr> Ptr<T> {
             PtrKind::StackArray(ref weak) | PtrKind::HeapArray(ref weak) => {
                 weak.upgrade().expect("ub: dangling pointer").borrow()[self.offset].clone()
             }
-            PtrKind::Reinterpreted(ref data) => {
-                let mut buf = vec![0u8; std::mem::size_of::<T>()];
-                data.read_bytes(self.offset, &mut buf);
+            PtrKind::Reinterpreted(ref view) => {
+                let mut buf = vec![0u8; T::byte_size()];
+                view.alloc.read_bytes(self.offset, &mut buf);
                 T::from_bytes(&buf)
             }
         }
@@ -535,7 +546,7 @@ impl<T: std::cmp::Ord> Ptr<T> {
                 let strong = weak.upgrade().expect("ub: dangling pointer");
                 (*strong.borrow_mut())[self.get_offset()..last].sort();
             }
-            PtrKind::Reinterpreted(..) => {
+            PtrKind::Reinterpreted(_) => {
                 panic!("sorting not supported for reinterpreted pointers")
             }
         }
@@ -580,7 +591,7 @@ impl<T: Clone> Ptr<T> {
                 let mut borrow = strong.borrow_mut();
                 sort(&mut borrow, self.get_offset(), last, &mut cmp);
             }
-            PtrKind::Reinterpreted(..) => {
+            PtrKind::Reinterpreted(_) => {
                 panic!("sorting not supported for reinterpreted pointers")
             }
         }
@@ -856,7 +867,7 @@ impl<T> ToOwnedOption<T, T> for Ptr<T> {
             }
             PtrKind::Vec(_) => panic!("Can't own a vector"),
             PtrKind::HeapArray(_) => panic!("Can't own an array variable as single"),
-            PtrKind::Reinterpreted(..) => panic!("Can't own a reinterpreted pointer"),
+            PtrKind::Reinterpreted(_) => panic!("Can't own a reinterpreted pointer"),
         }
     }
 }
@@ -882,7 +893,7 @@ impl<T> ToOwnedOption<T, Box<[T]>> for Ptr<T> {
             }
             PtrKind::Vec(_) => panic!("Can't own a vector"),
             PtrKind::HeapSingle(_) => panic!("Can't own a single variable as an array"),
-            PtrKind::Reinterpreted(..) => panic!("Can't own a reinterpreted pointer"),
+            PtrKind::Reinterpreted(_) => panic!("Can't own a reinterpreted pointer"),
         }
     }
 }
@@ -898,7 +909,7 @@ impl<T> fmt::Debug for Ptr<T> {
                 (Weak::as_ptr(w) as usize).wrapping_add(self.byte_offset())
             }
             PtrKind::Vec(w) => (Weak::as_ptr(w) as usize).wrapping_add(self.byte_offset()),
-            PtrKind::Reinterpreted(data) => data.address().wrapping_add(self.byte_offset()),
+            PtrKind::Reinterpreted(view) => view.alloc.address().wrapping_add(self.byte_offset()),
         };
         write!(f, "0x{:x}", addr)
     }
@@ -994,9 +1005,9 @@ impl Ptr<u8> {
                 let raw = strong.borrow();
                 raw[start..end].to_vec()
             }
-            PtrKind::Reinterpreted(ref data) => {
+            PtrKind::Reinterpreted(ref view) => {
                 let mut buf = vec![0u8; end.wrapping_sub(start)];
-                data.read_bytes(start, &mut buf);
+                view.alloc.read_bytes(start, &mut buf);
                 buf
             }
         }
diff --git a/libcc2rs/src/reinterpret.rs b/libcc2rs/src/reinterpret.rs
index 452b35de..c554814f 100644
--- a/libcc2rs/src/reinterpret.rs
+++ b/libcc2rs/src/reinterpret.rs
@@ -4,6 +4,12 @@
 use std::{cell::RefCell, rc::Weak};
 
 pub trait ByteRepr: 'static {
+    fn byte_size() -> usize
+    where
+        Self: Sized,
+    {
+        std::mem::size_of::<Self>()
+    }
     fn to_bytes(&self, _buf: &mut [u8]) {
         panic!("ByteRepr not supported for this type");
     }
@@ -83,7 +89,7 @@ pub trait OriginalAlloc {
 // Only serializes the overlapping elements, not the whole slice.
 fn slice_read_bytes<S: ByteRepr>(slice: &[S], byte_offset: usize, buf: &mut [u8]) {
     let len = buf.len();
-    let elem_size = std::mem::size_of::<S>();
+    let elem_size = S::byte_size();
     let first_elem = byte_offset / elem_size;
     let last_elem = (byte_offset + len).div_ceil(elem_size);
     let tmp_len = (last_elem - first_elem) * elem_size;
@@ -98,7 +104,7 @@ fn slice_read_bytes<S: ByteRepr>(slice: &[S], byte_offset: usize, buf: &mut [u8]
 // Write `data` at `byte_offset` into a slice of S elements.
 // Only deserializes/reserializes the overlapping elements.
 fn slice_write_bytes<S: ByteRepr>(slice: &mut [S], byte_offset: usize, data: &[u8]) {
-    let elem_size = std::mem::size_of::<S>();
+    let elem_size = S::byte_size();
     let mut elem_buf = vec![0u8; elem_size];
     let first_elem = byte_offset / elem_size;
     let num_elem = data.len().div_ceil(elem_size);
@@ -136,7 +142,7 @@ impl<T: ByteRepr> OriginalAlloc for SingleOriginalAlloc<T> {
     }
 
     fn total_byte_len(&self) -> usize {
-        std::mem::size_of::<T>()
+        T::byte_size()
     }
 
     fn address(&self) -> usize {
@@ -190,7 +196,7 @@ impl<T: AsSlice + 'static> OriginalAlloc for SliceOriginalAlloc<T> {
     fn total_byte_len(&self) -> usize {
         let rc = self.weak.upgrade().expect("ub: dangling pointer");
         let val = rc.borrow();
-        std::mem::size_of_val(val.as_slice())
+        val.as_slice().len() * <T::Elem as ByteRepr>::byte_size()
     }
 
     fn address(&self) -> usize {

From a07a40fbc050743d06c68de5a60f7113a6142b4a Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Thu, 25 Jun 2026 15:06:31 +0100
Subject: [PATCH 03/15] Delete unused function

---
 .../converter/models/converter_refcount.cpp   | 19 -------------------
 1 file changed, 19 deletions(-)

diff --git a/cpp2rust/converter/models/converter_refcount.cpp b/cpp2rust/converter/models/converter_refcount.cpp
index d104e4b9..3b142ca2 100644
--- a/cpp2rust/converter/models/converter_refcount.cpp
+++ b/cpp2rust/converter/models/converter_refcount.cpp
@@ -545,28 +545,9 @@ void ConverterRefCount::AddDropTrait(const clang::CXXRecordDecl *decl) {
   StrCat('}');
 }
 
-static bool recordImplementsByteRepr(const clang::RecordDecl *decl) {
-  if (decl->isUnion()) {
-    return false;
-  }
-
-  // ByteRepr is only supported for user-defined structs that contain ByteRepr
-  // fields.
-  for (auto *f : decl->fields()) {
-    auto qt = f->getType();
-    if (!qt->isIntegerType() && !qt->isFloatingType() &&
-        !qt->isEnumeralType()) {
-      return false;
-    }
-  }
-
-  return true;
-}
-
 void ConverterRefCount::AddByteReprTrait(const clang::RecordDecl *decl) {
   auto struct_name = GetRecordName(decl);
 
-
   if (!TypeImplementsByteRepr(ctx_.getCanonicalTagType(decl))) {
     StrCat(std::format("impl ByteRepr for {}", struct_name));
     PushBrace brace(*this);

From 7db50020b618fdff2b9b1a6a4cae91db10b91f35 Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Thu, 25 Jun 2026 15:06:55 +0100
Subject: [PATCH 04/15] Add correct from_bytes type

---
 cpp2rust/converter/models/converter_refcount.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/cpp2rust/converter/models/converter_refcount.cpp b/cpp2rust/converter/models/converter_refcount.cpp
index 3b142ca2..fa484685 100644
--- a/cpp2rust/converter/models/converter_refcount.cpp
+++ b/cpp2rust/converter/models/converter_refcount.cpp
@@ -585,9 +585,12 @@ void ConverterRefCount::AddByteReprTrait(const clang::RecordDecl *decl) {
     for (auto *field : decl->fields()) {
       auto byte_off = layout.getFieldOffset(idx) / 8;
       auto byte_size = ctx_.getTypeSize(field->getType()) / 8;
+      PushConversionKind push(*this, ConversionKind::FullRefCount);
+      std::string storage_ty = ToString(field->getType());
+      Unwrap(storage_ty, "Value<", ">");
       StrCat(std::format(
           "{}: Rc::new(RefCell::new(<{}>::from_bytes(&buf[{}..{}]))),",
-          GetNamedDeclAsString(field), Mapper::Map(field->getType()), byte_off,
+          GetNamedDeclAsString(field), storage_ty, byte_off,
           byte_off + byte_size));
       ++idx;
     }

From c66a712327ddb386baea49e68099049c2162e017 Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Thu, 25 Jun 2026 15:07:43 +0100
Subject: [PATCH 05/15] Update tests

---
 .../out/refcount/cross_tu_tag_collision.rs    |  3 +
 tests/unit/out/refcount/addr_of_global.rs     |  3 +
 tests/unit/out/refcount/anonymous-struct.rs   | 61 ++++++++++++++++++-
 tests/unit/out/refcount/anonymous-struct_c.rs | 61 ++++++++++++++++++-
 tests/unit/out/refcount/anonymous_enum.rs     | 56 ++---------------
 tests/unit/out/refcount/anonymous_enum_c.rs   | 56 ++---------------
 tests/unit/out/refcount/array_const_init.rs   | 18 +++++-
 .../out/refcount/array_of_noncopy_struct.rs   | 16 ++++-
 tests/unit/out/refcount/bounded_struct_ptr.rs |  3 +
 tests/unit/out/refcount/c_struct.rs           | 30 ++++++---
 tests/unit/out/refcount/class.rs              | 19 +++++-
 tests/unit/out/refcount/class_templates.rs    | 42 ++++++++++++-
 tests/unit/out/refcount/clone_vs_move.rs      |  3 +
 tests/unit/out/refcount/complex_function.rs   |  3 +
 tests/unit/out/refcount/exprs.rs              |  3 +
 tests/unit/out/refcount/fft.rs                |  3 +
 tests/unit/out/refcount/fn_ptr_stable_sort.rs |  3 +
 .../refcount/foreach_disjoint_field_borrow.rs | 16 ++++-
 .../unit/out/refcount/function_overloading.rs |  3 +
 .../refcount/global_without_initializer.rs    |  3 +
 .../out/refcount/goto_aggregate_default.rs    |  3 +
 tests/unit/out/refcount/huffman.rs            | 26 +++++++-
 .../refcount/immutable-deref-on-func-call.rs  |  3 +
 tests/unit/out/refcount/implicit_autoref.rs   | 14 ++++-
 tests/unit/out/refcount/init.rs               |  3 +
 tests/unit/out/refcount/kruskal.rs            | 45 +++++++++++++-
 .../refcount/local_anon_struct_collision.rs   |  6 ++
 .../unit/out/refcount/memcpy_struct_struct.rs |  7 ++-
 tests/unit/out/refcount/nested_structs.rs     | 18 ++++++
 tests/unit/out/refcount/new_struct.rs         |  3 +
 tests/unit/out/refcount/operator_less_than.rs |  3 +
 tests/unit/out/refcount/pod.rs                |  3 +
 tests/unit/out/refcount/pointers.rs           |  3 +
 tests/unit/out/refcount/polymorphism.rs       |  6 ++
 tests/unit/out/refcount/push_emplace_back.rs  | 21 ++++++-
 tests/unit/out/refcount/random.rs             |  3 +
 .../out/refcount/reinterpret_cast_struct.rs   |  3 +
 .../reinterpret_cast_struct_to_struct.rs      |  6 ++
 tests/unit/out/refcount/reserved_keywords.rs  |  3 +
 .../unit/out/refcount/static_var_in_class.rs  |  6 ++
 tests/unit/out/refcount/struct_ctor.rs        |  3 +
 tests/unit/out/refcount/struct_ptr.rs         |  3 +
 .../unit/out/refcount/typedef-anon-struct.rs  | 17 +++++-
 tests/unit/out/refcount/unique_ptr.rs         | 17 +++++-
 .../out/refcount/unique_ptr_const_deref.rs    | 14 ++++-
 tests/unit/out/refcount/unique_ptr_nested.rs  | 17 +++++-
 tests/unit/out/refcount/unique_ptr_struct.rs  |  3 +
 tests/unit/out/refcount/va_arg_struct_ctx.rs  |  3 +
 tests/unit/out/refcount/void_cast.rs          | 17 +++++-
 49 files changed, 547 insertions(+), 137 deletions(-)

diff --git a/tests/multi-file/cross_tu_tag_collision/out/refcount/cross_tu_tag_collision.rs b/tests/multi-file/cross_tu_tag_collision/out/refcount/cross_tu_tag_collision.rs
index 90529368..981fa9ae 100644
--- a/tests/multi-file/cross_tu_tag_collision/out/refcount/cross_tu_tag_collision.rs
+++ b/tests/multi-file/cross_tu_tag_collision/out/refcount/cross_tu_tag_collision.rs
@@ -11,6 +11,9 @@ pub struct widget {
     pub id: Value<i32>,
 }
 impl ByteRepr for widget {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.id.borrow()).to_bytes(&mut buf[0..4]);
     }
diff --git a/tests/unit/out/refcount/addr_of_global.rs b/tests/unit/out/refcount/addr_of_global.rs
index 01ddb7f7..0d03ca3b 100644
--- a/tests/unit/out/refcount/addr_of_global.rs
+++ b/tests/unit/out/refcount/addr_of_global.rs
@@ -19,6 +19,9 @@ impl Clone for Inner {
     }
 }
 impl ByteRepr for Inner {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.value.borrow()).to_bytes(&mut buf[0..4]);
     }
diff --git a/tests/unit/out/refcount/anonymous-struct.rs b/tests/unit/out/refcount/anonymous-struct.rs
index fcd7db80..ad257c16 100644
--- a/tests/unit/out/refcount/anonymous-struct.rs
+++ b/tests/unit/out/refcount/anonymous-struct.rs
@@ -21,6 +21,9 @@ impl Clone for Outer_Named {
     }
 }
 impl ByteRepr for Outer_Named {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.a.borrow()).to_bytes(&mut buf[0..4]);
         (*self.b.borrow()).to_bytes(&mut buf[4..8]);
@@ -47,6 +50,9 @@ impl Clone for anon_0 {
     }
 }
 impl ByteRepr for anon_0 {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.c.borrow()).to_bytes(&mut buf[0..4]);
         (*self.d.borrow()).to_bytes(&mut buf[4..8]);
@@ -73,6 +79,9 @@ impl Clone for anon_1 {
     }
 }
 impl ByteRepr for anon_1 {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.g.borrow()).to_bytes(&mut buf[0..4]);
         (*self.h.borrow()).to_bytes(&mut buf[4..8]);
@@ -99,6 +108,9 @@ impl Clone for anon_2 {
     }
 }
 impl ByteRepr for anon_2 {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.e.borrow()).to_bytes(&mut buf[0..4]);
         (*self.f.borrow()).to_bytes(&mut buf[4..8]);
@@ -123,6 +135,9 @@ impl Clone for anon_4 {
     }
 }
 impl ByteRepr for anon_4 {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.j.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -145,6 +160,9 @@ impl Clone for anon_5 {
     }
 }
 impl ByteRepr for anon_5 {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.k.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -170,7 +188,23 @@ impl Clone for anon_3 {
         this
     }
 }
-impl ByteRepr for anon_3 {}
+impl ByteRepr for anon_3 {
+    fn byte_size() -> usize {
+        12
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.i.borrow()).to_bytes(&mut buf[0..4]);
+        (*self.inner_named.borrow()).to_bytes(&mut buf[4..8]);
+        (*self.anon_5.borrow()).to_bytes(&mut buf[8..12]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            i: Rc::new(RefCell::new(<i32>::from_bytes(&buf[0..4]))),
+            inner_named: Rc::new(RefCell::new(<anon_4>::from_bytes(&buf[4..8]))),
+            anon_5: Rc::new(RefCell::new(<anon_5>::from_bytes(&buf[8..12]))),
+        }
+    }
+}
 #[derive(Default)]
 pub struct Outer {
     pub named: Value<Outer_Named>,
@@ -191,7 +225,27 @@ impl Clone for Outer {
         this
     }
 }
-impl ByteRepr for Outer {}
+impl ByteRepr for Outer {
+    fn byte_size() -> usize {
+        44
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.named.borrow()).to_bytes(&mut buf[0..8]);
+        (*self.anonymous_named_0.borrow()).to_bytes(&mut buf[8..16]);
+        (*self.anonymous_named_1.borrow()).to_bytes(&mut buf[16..24]);
+        (*self.anon_2.borrow()).to_bytes(&mut buf[24..32]);
+        (*self.anon_3.borrow()).to_bytes(&mut buf[32..44]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            named: Rc::new(RefCell::new(<Outer_Named>::from_bytes(&buf[0..8]))),
+            anonymous_named_0: Rc::new(RefCell::new(<anon_0>::from_bytes(&buf[8..16]))),
+            anonymous_named_1: Rc::new(RefCell::new(<anon_1>::from_bytes(&buf[16..24]))),
+            anon_2: Rc::new(RefCell::new(<anon_2>::from_bytes(&buf[24..32]))),
+            anon_3: Rc::new(RefCell::new(<anon_3>::from_bytes(&buf[32..44]))),
+        }
+    }
+}
 pub fn main() {
     std::process::exit(main_0());
 }
@@ -274,6 +328,9 @@ fn main_0() -> i32 {
         }
     }
     impl ByteRepr for anon_6 {
+        fn byte_size() -> usize {
+            8
+        }
         fn to_bytes(&self, buf: &mut [u8]) {
             (*self.x.borrow()).to_bytes(&mut buf[0..4]);
             (*self.z.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/anonymous-struct_c.rs b/tests/unit/out/refcount/anonymous-struct_c.rs
index 23ce8df8..970d6e99 100644
--- a/tests/unit/out/refcount/anonymous-struct_c.rs
+++ b/tests/unit/out/refcount/anonymous-struct_c.rs
@@ -12,6 +12,9 @@ pub struct Named {
     pub b: Value<i32>,
 }
 impl ByteRepr for Named {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.a.borrow()).to_bytes(&mut buf[0..4]);
         (*self.b.borrow()).to_bytes(&mut buf[4..8]);
@@ -29,6 +32,9 @@ pub struct anon_0 {
     pub d: Value<i32>,
 }
 impl ByteRepr for anon_0 {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.c.borrow()).to_bytes(&mut buf[0..4]);
         (*self.d.borrow()).to_bytes(&mut buf[4..8]);
@@ -46,6 +52,9 @@ pub struct anon_1 {
     pub h: Value<i32>,
 }
 impl ByteRepr for anon_1 {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.g.borrow()).to_bytes(&mut buf[0..4]);
         (*self.h.borrow()).to_bytes(&mut buf[4..8]);
@@ -63,6 +72,9 @@ pub struct anon_2 {
     pub f: Value<i32>,
 }
 impl ByteRepr for anon_2 {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.e.borrow()).to_bytes(&mut buf[0..4]);
         (*self.f.borrow()).to_bytes(&mut buf[4..8]);
@@ -79,6 +91,9 @@ pub struct anon_4 {
     pub j: Value<i32>,
 }
 impl ByteRepr for anon_4 {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.j.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -93,6 +108,9 @@ pub struct anon_5 {
     pub k: Value<i32>,
 }
 impl ByteRepr for anon_5 {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.k.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -108,7 +126,23 @@ pub struct anon_3 {
     pub inner_named: Value<anon_4>,
     pub anon_5: Value<anon_5>,
 }
-impl ByteRepr for anon_3 {}
+impl ByteRepr for anon_3 {
+    fn byte_size() -> usize {
+        12
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.i.borrow()).to_bytes(&mut buf[0..4]);
+        (*self.inner_named.borrow()).to_bytes(&mut buf[4..8]);
+        (*self.anon_5.borrow()).to_bytes(&mut buf[8..12]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            i: Rc::new(RefCell::new(<i32>::from_bytes(&buf[0..4]))),
+            inner_named: Rc::new(RefCell::new(<anon_4>::from_bytes(&buf[4..8]))),
+            anon_5: Rc::new(RefCell::new(<anon_5>::from_bytes(&buf[8..12]))),
+        }
+    }
+}
 #[derive(Default)]
 pub struct Outer {
     pub named: Value<Named>,
@@ -117,7 +151,27 @@ pub struct Outer {
     pub anon_2: Value<anon_2>,
     pub anon_3: Value<anon_3>,
 }
-impl ByteRepr for Outer {}
+impl ByteRepr for Outer {
+    fn byte_size() -> usize {
+        44
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.named.borrow()).to_bytes(&mut buf[0..8]);
+        (*self.anon0.borrow()).to_bytes(&mut buf[8..16]);
+        (*self.anon1.borrow()).to_bytes(&mut buf[16..24]);
+        (*self.anon_2.borrow()).to_bytes(&mut buf[24..32]);
+        (*self.anon_3.borrow()).to_bytes(&mut buf[32..44]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            named: Rc::new(RefCell::new(<Named>::from_bytes(&buf[0..8]))),
+            anon0: Rc::new(RefCell::new(<anon_0>::from_bytes(&buf[8..16]))),
+            anon1: Rc::new(RefCell::new(<anon_1>::from_bytes(&buf[16..24]))),
+            anon_2: Rc::new(RefCell::new(<anon_2>::from_bytes(&buf[24..32]))),
+            anon_3: Rc::new(RefCell::new(<anon_3>::from_bytes(&buf[32..44]))),
+        }
+    }
+}
 pub fn main() {
     std::process::exit(main_0());
 }
@@ -176,6 +230,9 @@ fn main_0() -> i32 {
         pub z: Value<i32>,
     }
     impl ByteRepr for anon_6 {
+        fn byte_size() -> usize {
+            8
+        }
         fn to_bytes(&self, buf: &mut [u8]) {
             (*self.x.borrow()).to_bytes(&mut buf[0..4]);
             (*self.z.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/anonymous_enum.rs b/tests/unit/out/refcount/anonymous_enum.rs
index 9fbf91ed..f63deffd 100644
--- a/tests/unit/out/refcount/anonymous_enum.rs
+++ b/tests/unit/out/refcount/anonymous_enum.rs
@@ -22,14 +22,6 @@ impl From<i32> for anon_0 {
     }
 }
 libcc2rs::impl_enum_inc_dec!(anon_0);
-impl ByteRepr for anon_0 {
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self as i32).to_bytes(buf);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        <anon_0>::from(i32::from_bytes(buf))
-    }
-}
 #[derive(Clone, Copy, PartialEq, Debug, Default)]
 enum anon_1 {
     #[default]
@@ -46,14 +38,6 @@ impl From<i32> for anon_1 {
     }
 }
 libcc2rs::impl_enum_inc_dec!(anon_1);
-impl ByteRepr for anon_1 {
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self as i32).to_bytes(buf);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        <anon_1>::from(i32::from_bytes(buf))
-    }
-}
 #[derive(Default)]
 pub struct S {
     pub a: Value<i32>,
@@ -67,6 +51,9 @@ impl Clone for S {
     }
 }
 impl ByteRepr for S {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.a.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -92,14 +79,6 @@ impl From<i32> for TdEnum {
     }
 }
 libcc2rs::impl_enum_inc_dec!(TdEnum);
-impl ByteRepr for TdEnum {
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self as i32).to_bytes(buf);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        <TdEnum>::from(i32::from_bytes(buf))
-    }
-}
 #[derive(Clone, Copy, PartialEq, Debug, Default)]
 enum anon_2 {
     #[default]
@@ -116,14 +95,6 @@ impl From<i32> for anon_2 {
     }
 }
 libcc2rs::impl_enum_inc_dec!(anon_2);
-impl ByteRepr for anon_2 {
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self as i32).to_bytes(buf);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        <anon_2>::from(i32::from_bytes(buf))
-    }
-}
 #[derive(Default)]
 pub struct WithAnonField {
     pub a: Value<i32>,
@@ -138,18 +109,7 @@ impl Clone for WithAnonField {
         this
     }
 }
-impl ByteRepr for WithAnonField {
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.a.borrow()).to_bytes(&mut buf[0..4]);
-        (*self.field.borrow()).to_bytes(&mut buf[4..8]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            a: Rc::new(RefCell::new(<i32>::from_bytes(&buf[0..4]))),
-            field: Rc::new(RefCell::new(<anon_2>::from_bytes(&buf[4..8]))),
-        }
-    }
-}
+impl ByteRepr for WithAnonField {}
 pub fn main() {
     std::process::exit(main_0());
 }
@@ -170,14 +130,6 @@ fn main_0() -> i32 {
         }
     }
     libcc2rs::impl_enum_inc_dec!(anon_3);
-    impl ByteRepr for anon_3 {
-        fn to_bytes(&self, buf: &mut [u8]) {
-            (*self as i32).to_bytes(buf);
-        }
-        fn from_bytes(buf: &[u8]) -> Self {
-            <anon_3>::from(i32::from_bytes(buf))
-        }
-    };
     assert!(((anon_0::FIRST_A as i32) != (anon_0::FIRST_B as i32)));
     assert!(((anon_1::SECOND_A as i32) != (anon_1::SECOND_B as i32)));
     assert!(((anon_3::THIRD_A as i32) != (anon_3::THIRD_B as i32)));
diff --git a/tests/unit/out/refcount/anonymous_enum_c.rs b/tests/unit/out/refcount/anonymous_enum_c.rs
index 199dc233..43dc943b 100644
--- a/tests/unit/out/refcount/anonymous_enum_c.rs
+++ b/tests/unit/out/refcount/anonymous_enum_c.rs
@@ -22,14 +22,6 @@ impl From<i32> for anon_0 {
     }
 }
 libcc2rs::impl_enum_inc_dec!(anon_0);
-impl ByteRepr for anon_0 {
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self as i32).to_bytes(buf);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        <anon_0>::from(i32::from_bytes(buf))
-    }
-}
 #[derive(Clone, Copy, PartialEq, Debug, Default)]
 enum anon_1 {
     #[default]
@@ -46,19 +38,14 @@ impl From<i32> for anon_1 {
     }
 }
 libcc2rs::impl_enum_inc_dec!(anon_1);
-impl ByteRepr for anon_1 {
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self as i32).to_bytes(buf);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        <anon_1>::from(i32::from_bytes(buf))
-    }
-}
 #[derive(Default)]
 pub struct S {
     pub a: Value<i32>,
 }
 impl ByteRepr for S {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.a.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -84,14 +71,6 @@ impl From<i32> for TdEnum_enum {
     }
 }
 libcc2rs::impl_enum_inc_dec!(TdEnum_enum);
-impl ByteRepr for TdEnum_enum {
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self as i32).to_bytes(buf);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        <TdEnum_enum>::from(i32::from_bytes(buf))
-    }
-}
 #[derive(Clone, Copy, PartialEq, Debug, Default)]
 enum anon_2 {
     #[default]
@@ -108,31 +87,12 @@ impl From<i32> for anon_2 {
     }
 }
 libcc2rs::impl_enum_inc_dec!(anon_2);
-impl ByteRepr for anon_2 {
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self as i32).to_bytes(buf);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        <anon_2>::from(i32::from_bytes(buf))
-    }
-}
 #[derive(Default)]
 pub struct WithAnonField {
     pub a: Value<i32>,
     pub field: Value<anon_2>,
 }
-impl ByteRepr for WithAnonField {
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.a.borrow()).to_bytes(&mut buf[0..4]);
-        (*self.field.borrow()).to_bytes(&mut buf[4..8]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            a: Rc::new(RefCell::new(<i32>::from_bytes(&buf[0..4]))),
-            field: Rc::new(RefCell::new(<anon_2>::from_bytes(&buf[4..8]))),
-        }
-    }
-}
+impl ByteRepr for WithAnonField {}
 pub fn main() {
     std::process::exit(main_0());
 }
@@ -153,14 +113,6 @@ fn main_0() -> i32 {
         }
     }
     libcc2rs::impl_enum_inc_dec!(anon_3);
-    impl ByteRepr for anon_3 {
-        fn to_bytes(&self, buf: &mut [u8]) {
-            (*self as i32).to_bytes(buf);
-        }
-        fn from_bytes(buf: &[u8]) -> Self {
-            <anon_3>::from(i32::from_bytes(buf))
-        }
-    };
     assert!(((((anon_0::FIRST_A as i32) != (anon_0::FIRST_B as i32)) as i32) != 0));
     assert!(((((anon_1::SECOND_A as i32) != (anon_1::SECOND_B as i32)) as i32) != 0));
     assert!(((((anon_3::THIRD_A as i32) != (anon_3::THIRD_B as i32)) as i32) != 0));
diff --git a/tests/unit/out/refcount/array_const_init.rs b/tests/unit/out/refcount/array_const_init.rs
index 784f3a73..7a2cf78d 100644
--- a/tests/unit/out/refcount/array_const_init.rs
+++ b/tests/unit/out/refcount/array_const_init.rs
@@ -25,7 +25,23 @@ impl Default for S {
         }
     }
 }
-impl ByteRepr for S {}
+impl ByteRepr for S {
+    fn byte_size() -> usize {
+        20
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.head.borrow()).to_bytes(&mut buf[0..4]);
+        (*self.tail.borrow()).to_bytes(&mut buf[4..16]);
+        (*self.buf.borrow()).to_bytes(&mut buf[16..20]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            head: Rc::new(RefCell::new(<i32>::from_bytes(&buf[0..4]))),
+            tail: Rc::new(RefCell::new(<Box<[i32]>>::from_bytes(&buf[4..16]))),
+            buf: Rc::new(RefCell::new(<Box<[u8]>>::from_bytes(&buf[16..20]))),
+        }
+    }
+}
 thread_local!(
     pub static s_0: Value<S> = Rc::new(RefCell::new(S {
         head: Rc::new(RefCell::new(5)),
diff --git a/tests/unit/out/refcount/array_of_noncopy_struct.rs b/tests/unit/out/refcount/array_of_noncopy_struct.rs
index 4af56349..0c91af6d 100644
--- a/tests/unit/out/refcount/array_of_noncopy_struct.rs
+++ b/tests/unit/out/refcount/array_of_noncopy_struct.rs
@@ -20,7 +20,21 @@ impl Clone for NonCopy {
         this
     }
 }
-impl ByteRepr for NonCopy {}
+impl ByteRepr for NonCopy {
+    fn byte_size() -> usize {
+        32
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.data.borrow()).to_bytes(&mut buf[0..24]);
+        (*self.tag.borrow()).to_bytes(&mut buf[24..28]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            data: Rc::new(RefCell::new(<Vec<i32>>::from_bytes(&buf[0..24]))),
+            tag: Rc::new(RefCell::new(<i32>::from_bytes(&buf[24..28]))),
+        }
+    }
+}
 pub fn main() {
     std::process::exit(main_0());
 }
diff --git a/tests/unit/out/refcount/bounded_struct_ptr.rs b/tests/unit/out/refcount/bounded_struct_ptr.rs
index 477a71a6..6da5e2fb 100644
--- a/tests/unit/out/refcount/bounded_struct_ptr.rs
+++ b/tests/unit/out/refcount/bounded_struct_ptr.rs
@@ -21,6 +21,9 @@ impl Clone for Foo {
     }
 }
 impl ByteRepr for Foo {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x1.borrow()).to_bytes(&mut buf[0..4]);
         (*self.x2.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/c_struct.rs b/tests/unit/out/refcount/c_struct.rs
index 36ebdeb4..a0985ec8 100644
--- a/tests/unit/out/refcount/c_struct.rs
+++ b/tests/unit/out/refcount/c_struct.rs
@@ -12,6 +12,9 @@ pub struct Point {
     pub y: Value<i32>,
 }
 impl ByteRepr for Point {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
         (*self.y.borrow()).to_bytes(&mut buf[4..8]);
@@ -28,7 +31,21 @@ pub struct Line {
     pub start: Value<Point>,
     pub end: Value<Point>,
 }
-impl ByteRepr for Line {}
+impl ByteRepr for Line {
+    fn byte_size() -> usize {
+        16
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.start.borrow()).to_bytes(&mut buf[0..8]);
+        (*self.end.borrow()).to_bytes(&mut buf[8..16]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            start: Rc::new(RefCell::new(<Point>::from_bytes(&buf[0..8]))),
+            end: Rc::new(RefCell::new(<Point>::from_bytes(&buf[8..16]))),
+        }
+    }
+}
 #[derive(Default)]
 pub struct Node {
     pub value: Value<i32>,
@@ -53,20 +70,15 @@ impl From<i32> for Color {
     }
 }
 libcc2rs::impl_enum_inc_dec!(Color);
-impl ByteRepr for Color {
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self as i32).to_bytes(buf);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        <Color>::from(i32::from_bytes(buf))
-    }
-}
 #[derive(Default)]
 pub struct Inner {
     pub a: Value<i32>,
     pub b: Value<i32>,
 }
 impl ByteRepr for Inner {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.a.borrow()).to_bytes(&mut buf[0..4]);
         (*self.b.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/class.rs b/tests/unit/out/refcount/class.rs
index a0c1f970..ff1c3cf4 100644
--- a/tests/unit/out/refcount/class.rs
+++ b/tests/unit/out/refcount/class.rs
@@ -54,6 +54,9 @@ impl Clone for Pair {
     }
 }
 impl ByteRepr for Pair {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.first.borrow()).to_bytes(&mut buf[0..4]);
         (*self.second.borrow()).to_bytes(&mut buf[4..8]);
@@ -87,7 +90,21 @@ impl Clone for Route {
         this
     }
 }
-impl ByteRepr for Route {}
+impl ByteRepr for Route {
+    fn byte_size() -> usize {
+        16
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.path.borrow()).to_bytes(&mut buf[0..8]);
+        (*self.cost.borrow()).to_bytes(&mut buf[8..16]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            path: Rc::new(RefCell::new(<Pair>::from_bytes(&buf[0..8]))),
+            cost: Rc::new(RefCell::new(<f64>::from_bytes(&buf[8..16]))),
+        }
+    }
+}
 pub fn RandomRoute_0(route: Ptr<Route>) -> i32 {
     if (((*(*(*route.upgrade().deref()).path.borrow()).first.borrow()) % 2) != 0) {
         return ({
diff --git a/tests/unit/out/refcount/class_templates.rs b/tests/unit/out/refcount/class_templates.rs
index 3cbce86e..183fbd41 100644
--- a/tests/unit/out/refcount/class_templates.rs
+++ b/tests/unit/out/refcount/class_templates.rs
@@ -42,7 +42,19 @@ impl Clone for MyContainer_int_ {
         this
     }
 }
-impl ByteRepr for MyContainer_int_ {}
+impl ByteRepr for MyContainer_int_ {
+    fn byte_size() -> usize {
+        24
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.vec_.borrow()).to_bytes(&mut buf[0..24]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            vec_: Rc::new(RefCell::new(<Vec<i32>>::from_bytes(&buf[0..24]))),
+        }
+    }
+}
 #[derive(Default)]
 pub struct MyContainer_char_ {
     vec_: Value<Vec<u8>>,
@@ -79,7 +91,19 @@ impl Clone for MyContainer_char_ {
         this
     }
 }
-impl ByteRepr for MyContainer_char_ {}
+impl ByteRepr for MyContainer_char_ {
+    fn byte_size() -> usize {
+        24
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.vec_.borrow()).to_bytes(&mut buf[0..24]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            vec_: Rc::new(RefCell::new(<Vec<u8>>::from_bytes(&buf[0..24]))),
+        }
+    }
+}
 #[derive(Default)]
 pub struct MyContainer_float_ {
     vec_: Value<Vec<f32>>,
@@ -116,7 +140,19 @@ impl Clone for MyContainer_float_ {
         this
     }
 }
-impl ByteRepr for MyContainer_float_ {}
+impl ByteRepr for MyContainer_float_ {
+    fn byte_size() -> usize {
+        24
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.vec_.borrow()).to_bytes(&mut buf[0..24]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            vec_: Rc::new(RefCell::new(<Vec<f32>>::from_bytes(&buf[0..24]))),
+        }
+    }
+}
 pub fn main() {
     std::process::exit(main_0());
 }
diff --git a/tests/unit/out/refcount/clone_vs_move.rs b/tests/unit/out/refcount/clone_vs_move.rs
index 9f6ee411..1953e3d9 100644
--- a/tests/unit/out/refcount/clone_vs_move.rs
+++ b/tests/unit/out/refcount/clone_vs_move.rs
@@ -19,6 +19,9 @@ impl Clone for Bar {
     }
 }
 impl ByteRepr for Bar {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.w.borrow()).to_bytes(&mut buf[0..4]);
     }
diff --git a/tests/unit/out/refcount/complex_function.rs b/tests/unit/out/refcount/complex_function.rs
index 861fee9f..737edc12 100644
--- a/tests/unit/out/refcount/complex_function.rs
+++ b/tests/unit/out/refcount/complex_function.rs
@@ -30,6 +30,9 @@ impl Clone for X1 {
     }
 }
 impl ByteRepr for X1 {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.v.borrow()).to_bytes(&mut buf[0..4]);
     }
diff --git a/tests/unit/out/refcount/exprs.rs b/tests/unit/out/refcount/exprs.rs
index 6a4a1646..e8a9eed6 100644
--- a/tests/unit/out/refcount/exprs.rs
+++ b/tests/unit/out/refcount/exprs.rs
@@ -19,6 +19,9 @@ impl Clone for X {
     }
 }
 impl ByteRepr for X {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
     }
diff --git a/tests/unit/out/refcount/fft.rs b/tests/unit/out/refcount/fft.rs
index 55e71cd7..12551ddb 100644
--- a/tests/unit/out/refcount/fft.rs
+++ b/tests/unit/out/refcount/fft.rs
@@ -21,6 +21,9 @@ impl Clone for Complex {
     }
 }
 impl ByteRepr for Complex {
+    fn byte_size() -> usize {
+        16
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.re.borrow()).to_bytes(&mut buf[0..8]);
         (*self.img.borrow()).to_bytes(&mut buf[8..16]);
diff --git a/tests/unit/out/refcount/fn_ptr_stable_sort.rs b/tests/unit/out/refcount/fn_ptr_stable_sort.rs
index 5182170f..da7b2e8a 100644
--- a/tests/unit/out/refcount/fn_ptr_stable_sort.rs
+++ b/tests/unit/out/refcount/fn_ptr_stable_sort.rs
@@ -21,6 +21,9 @@ impl Clone for Item {
     }
 }
 impl ByteRepr for Item {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.key.borrow()).to_bytes(&mut buf[0..4]);
         (*self.value.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/foreach_disjoint_field_borrow.rs b/tests/unit/out/refcount/foreach_disjoint_field_borrow.rs
index 66c9e892..57c56051 100644
--- a/tests/unit/out/refcount/foreach_disjoint_field_borrow.rs
+++ b/tests/unit/out/refcount/foreach_disjoint_field_borrow.rs
@@ -20,7 +20,21 @@ impl Clone for S {
         this
     }
 }
-impl ByteRepr for S {}
+impl ByteRepr for S {
+    fn byte_size() -> usize {
+        32
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.v.borrow()).to_bytes(&mut buf[0..24]);
+        (*self.a.borrow()).to_bytes(&mut buf[24..28]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            v: Rc::new(RefCell::new(<Vec<i32>>::from_bytes(&buf[0..24]))),
+            a: Rc::new(RefCell::new(<i32>::from_bytes(&buf[24..28]))),
+        }
+    }
+}
 pub fn main() {
     std::process::exit(main_0());
 }
diff --git a/tests/unit/out/refcount/function_overloading.rs b/tests/unit/out/refcount/function_overloading.rs
index 7110cd08..4e39bf8f 100644
--- a/tests/unit/out/refcount/function_overloading.rs
+++ b/tests/unit/out/refcount/function_overloading.rs
@@ -63,6 +63,9 @@ impl Clone for Foo {
     }
 }
 impl ByteRepr for Foo {
+    fn byte_size() -> usize {
+        1
+    }
     fn to_bytes(&self, buf: &mut [u8]) {}
     fn from_bytes(buf: &[u8]) -> Self {
         Self {}
diff --git a/tests/unit/out/refcount/global_without_initializer.rs b/tests/unit/out/refcount/global_without_initializer.rs
index 51fce351..f1dd9e2a 100644
--- a/tests/unit/out/refcount/global_without_initializer.rs
+++ b/tests/unit/out/refcount/global_without_initializer.rs
@@ -19,6 +19,9 @@ impl Clone for S {
     }
 }
 impl ByteRepr for S {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.a.borrow()).to_bytes(&mut buf[0..4]);
     }
diff --git a/tests/unit/out/refcount/goto_aggregate_default.rs b/tests/unit/out/refcount/goto_aggregate_default.rs
index 1043512f..c2c6d4d4 100644
--- a/tests/unit/out/refcount/goto_aggregate_default.rs
+++ b/tests/unit/out/refcount/goto_aggregate_default.rs
@@ -12,6 +12,9 @@ pub struct Point {
     pub y: Value<i32>,
 }
 impl ByteRepr for Point {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
         (*self.y.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/huffman.rs b/tests/unit/out/refcount/huffman.rs
index f320d46a..c36e85e0 100644
--- a/tests/unit/out/refcount/huffman.rs
+++ b/tests/unit/out/refcount/huffman.rs
@@ -200,7 +200,31 @@ impl MinHeap {
         }
     }
 }
-impl ByteRepr for MinHeap {}
+impl ByteRepr for MinHeap {
+    fn byte_size() -> usize {
+        32
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.size.borrow()).to_bytes(&mut buf[0..4]);
+        (*self.capacity.borrow()).to_bytes(&mut buf[4..8]);
+        (*self.arr.borrow()).to_bytes(&mut buf[8..16]);
+        (*self.next.borrow()).to_bytes(&mut buf[16..20]);
+        (*self.alloc.borrow()).to_bytes(&mut buf[24..32]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            size: Rc::new(RefCell::new(<i32>::from_bytes(&buf[0..4]))),
+            capacity: Rc::new(RefCell::new(<i32>::from_bytes(&buf[4..8]))),
+            arr: Rc::new(RefCell::new(
+                <Option<Value<Box<[Ptr<MinHeapNode>]>>>>::from_bytes(&buf[8..16]),
+            )),
+            next: Rc::new(RefCell::new(<i32>::from_bytes(&buf[16..20]))),
+            alloc: Rc::new(RefCell::new(
+                <Option<Value<Box<[MinHeapNode]>>>>::from_bytes(&buf[24..32]),
+            )),
+        }
+    }
+}
 pub fn AllocMinHeap_1(capacity: i32) -> Option<Value<MinHeap>> {
     let capacity: Value<i32> = Rc::new(RefCell::new(capacity));
     let minHeap: Value<Option<Value<MinHeap>>> =
diff --git a/tests/unit/out/refcount/immutable-deref-on-func-call.rs b/tests/unit/out/refcount/immutable-deref-on-func-call.rs
index 416e1438..84ae55c9 100644
--- a/tests/unit/out/refcount/immutable-deref-on-func-call.rs
+++ b/tests/unit/out/refcount/immutable-deref-on-func-call.rs
@@ -25,6 +25,9 @@ impl Clone for Item {
     }
 }
 impl ByteRepr for Item {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.value.borrow()).to_bytes(&mut buf[0..4]);
     }
diff --git a/tests/unit/out/refcount/implicit_autoref.rs b/tests/unit/out/refcount/implicit_autoref.rs
index f9b022a4..bda4df7e 100644
--- a/tests/unit/out/refcount/implicit_autoref.rs
+++ b/tests/unit/out/refcount/implicit_autoref.rs
@@ -18,7 +18,19 @@ impl Clone for Holder {
         this
     }
 }
-impl ByteRepr for Holder {}
+impl ByteRepr for Holder {
+    fn byte_size() -> usize {
+        24
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.v.borrow()).to_bytes(&mut buf[0..24]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            v: Rc::new(RefCell::new(<Vec<i32>>::from_bytes(&buf[0..24]))),
+        }
+    }
+}
 pub fn write_through_0(p: Ptr<i32>) {
     let p: Value<Ptr<i32>> = Rc::new(RefCell::new(p));
     (*p.borrow()).write(42);
diff --git a/tests/unit/out/refcount/init.rs b/tests/unit/out/refcount/init.rs
index f74601da..2fed9750 100644
--- a/tests/unit/out/refcount/init.rs
+++ b/tests/unit/out/refcount/init.rs
@@ -19,6 +19,9 @@ impl Clone for X {
     }
 }
 impl ByteRepr for X {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
     }
diff --git a/tests/unit/out/refcount/kruskal.rs b/tests/unit/out/refcount/kruskal.rs
index e558cab3..e2e21b98 100644
--- a/tests/unit/out/refcount/kruskal.rs
+++ b/tests/unit/out/refcount/kruskal.rs
@@ -23,6 +23,9 @@ impl Clone for Edge {
     }
 }
 impl ByteRepr for Edge {
+    fn byte_size() -> usize {
+        16
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.u.borrow()).to_bytes(&mut buf[0..4]);
         (*self.v.borrow()).to_bytes(&mut buf[4..8]);
@@ -277,14 +280,52 @@ impl DisjointSet {
         }
     }
 }
-impl ByteRepr for DisjointSet {}
+impl ByteRepr for DisjointSet {
+    fn byte_size() -> usize {
+        24
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.rank.borrow()).to_bytes(&mut buf[0..8]);
+        (*self.parent.borrow()).to_bytes(&mut buf[8..16]);
+        (*self.n.borrow()).to_bytes(&mut buf[16..20]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            rank: Rc::new(RefCell::new(<Option<Value<Box<[i32]>>>>::from_bytes(
+                &buf[0..8],
+            ))),
+            parent: Rc::new(RefCell::new(<Option<Value<Box<[i32]>>>>::from_bytes(
+                &buf[8..16],
+            ))),
+            n: Rc::new(RefCell::new(<i32>::from_bytes(&buf[16..20]))),
+        }
+    }
+}
 #[derive(Default)]
 pub struct Graph {
     pub edges: Value<Option<Value<Box<[Edge]>>>>,
     pub V: Value<i32>,
     pub E: Value<i32>,
 }
-impl ByteRepr for Graph {}
+impl ByteRepr for Graph {
+    fn byte_size() -> usize {
+        16
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.edges.borrow()).to_bytes(&mut buf[0..8]);
+        (*self.V.borrow()).to_bytes(&mut buf[8..12]);
+        (*self.E.borrow()).to_bytes(&mut buf[12..16]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            edges: Rc::new(RefCell::new(<Option<Value<Box<[Edge]>>>>::from_bytes(
+                &buf[0..8],
+            ))),
+            V: Rc::new(RefCell::new(<i32>::from_bytes(&buf[8..12]))),
+            E: Rc::new(RefCell::new(<i32>::from_bytes(&buf[12..16]))),
+        }
+    }
+}
 pub fn MSTKruskal_2(graph: Ptr<Graph>) -> f64 {
     ({
         let _arr: Ptr<Option<Value<Box<[Edge]>>>> = (*graph.upgrade().deref()).edges.as_pointer();
diff --git a/tests/unit/out/refcount/local_anon_struct_collision.rs b/tests/unit/out/refcount/local_anon_struct_collision.rs
index c4b23e73..d69250d0 100644
--- a/tests/unit/out/refcount/local_anon_struct_collision.rs
+++ b/tests/unit/out/refcount/local_anon_struct_collision.rs
@@ -13,6 +13,9 @@ pub fn first_0() -> i32 {
         pub y: Value<i32>,
     }
     impl ByteRepr for anon_1 {
+        fn byte_size() -> usize {
+            8
+        }
         fn to_bytes(&self, buf: &mut [u8]) {
             (*self.x.borrow()).to_bytes(&mut buf[0..4]);
             (*self.y.borrow()).to_bytes(&mut buf[4..8]);
@@ -36,6 +39,9 @@ pub fn second_2() -> i32 {
         pub b: Value<i64>,
     }
     impl ByteRepr for anon_3 {
+        fn byte_size() -> usize {
+            16
+        }
         fn to_bytes(&self, buf: &mut [u8]) {
             (*self.a.borrow()).to_bytes(&mut buf[0..8]);
             (*self.b.borrow()).to_bytes(&mut buf[8..16]);
diff --git a/tests/unit/out/refcount/memcpy_struct_struct.rs b/tests/unit/out/refcount/memcpy_struct_struct.rs
index 5ccc910e..158e7cff 100644
--- a/tests/unit/out/refcount/memcpy_struct_struct.rs
+++ b/tests/unit/out/refcount/memcpy_struct_struct.rs
@@ -21,6 +21,9 @@ impl Clone for Entry {
     }
 }
 impl ByteRepr for Entry {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.bits.borrow()).to_bytes(&mut buf[0..1]);
         (*self.value.borrow()).to_bytes(&mut buf[2..4]);
@@ -77,9 +80,7 @@ fn main_0() -> i32 {
             .to_any()
             .memcpy(
                 &(((table.as_pointer() as Ptr<Entry>).offset(0 as isize)) as Ptr<Entry>).to_any(),
-                (((*table_size.borrow()) as u64)
-                    .wrapping_mul((::std::mem::size_of::<Entry>() as u64))
-                    as usize) as usize,
+                (((*table_size.borrow()) as u64).wrapping_mul((4usize as u64)) as usize) as usize,
             );
         (((table.as_pointer() as Ptr<Entry>).offset((*table_size.borrow()) as isize)) as Ptr<Entry>)
             .to_any()
diff --git a/tests/unit/out/refcount/nested_structs.rs b/tests/unit/out/refcount/nested_structs.rs
index 491cdf12..febf11a8 100644
--- a/tests/unit/out/refcount/nested_structs.rs
+++ b/tests/unit/out/refcount/nested_structs.rs
@@ -19,6 +19,9 @@ impl Clone for Level0_Level1_1_Level2_1_Level3_1 {
     }
 }
 impl ByteRepr for Level0_Level1_1_Level2_1_Level3_1 {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x1.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -43,6 +46,9 @@ impl Clone for Level0_Level1_1_Level2_1_Level3_2 {
     }
 }
 impl ByteRepr for Level0_Level1_1_Level2_1_Level3_2 {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x1.borrow()).to_bytes(&mut buf[0..4]);
         (*self.x2.borrow()).to_bytes(&mut buf[4..8]);
@@ -67,6 +73,9 @@ impl Clone for Level0_Level1_1_Level2_1 {
     }
 }
 impl ByteRepr for Level0_Level1_1_Level2_1 {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x1.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -89,6 +98,9 @@ impl Clone for Level0_Level1_1 {
     }
 }
 impl ByteRepr for Level0_Level1_1 {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x1.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -113,6 +125,9 @@ impl Clone for Level0_Level1_2 {
     }
 }
 impl ByteRepr for Level0_Level1_2 {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x1.borrow()).to_bytes(&mut buf[0..4]);
         (*self.x2.borrow()).to_bytes(&mut buf[4..8]);
@@ -133,6 +148,9 @@ impl Clone for Level0 {
     }
 }
 impl ByteRepr for Level0 {
+    fn byte_size() -> usize {
+        1
+    }
     fn to_bytes(&self, buf: &mut [u8]) {}
     fn from_bytes(buf: &[u8]) -> Self {
         Self {}
diff --git a/tests/unit/out/refcount/new_struct.rs b/tests/unit/out/refcount/new_struct.rs
index 9885653c..05ba3965 100644
--- a/tests/unit/out/refcount/new_struct.rs
+++ b/tests/unit/out/refcount/new_struct.rs
@@ -21,6 +21,9 @@ impl Clone for Pair {
     }
 }
 impl ByteRepr for Pair {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
         (*self.y.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/operator_less_than.rs b/tests/unit/out/refcount/operator_less_than.rs
index cbf3d70b..94102602 100644
--- a/tests/unit/out/refcount/operator_less_than.rs
+++ b/tests/unit/out/refcount/operator_less_than.rs
@@ -62,6 +62,9 @@ impl Clone for Pair {
     }
 }
 impl ByteRepr for Pair {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
         (*self.y.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/pod.rs b/tests/unit/out/refcount/pod.rs
index 9e62ffde..5db49891 100644
--- a/tests/unit/out/refcount/pod.rs
+++ b/tests/unit/out/refcount/pod.rs
@@ -23,6 +23,9 @@ impl Clone for POD {
     }
 }
 impl ByteRepr for POD {
+    fn byte_size() -> usize {
+        12
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x1.borrow()).to_bytes(&mut buf[0..4]);
         (*self.x2.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/pointers.rs b/tests/unit/out/refcount/pointers.rs
index 065eb4bd..bbfc53c9 100644
--- a/tests/unit/out/refcount/pointers.rs
+++ b/tests/unit/out/refcount/pointers.rs
@@ -35,6 +35,9 @@ impl Clone for Test {
     }
 }
 impl ByteRepr for Test {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
     }
diff --git a/tests/unit/out/refcount/polymorphism.rs b/tests/unit/out/refcount/polymorphism.rs
index b1f4297f..b50c4491 100644
--- a/tests/unit/out/refcount/polymorphism.rs
+++ b/tests/unit/out/refcount/polymorphism.rs
@@ -23,6 +23,9 @@ impl Clone for Dog {
     }
 }
 impl ByteRepr for Dog {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {}
     fn from_bytes(buf: &[u8]) -> Self {
         Self {}
@@ -47,6 +50,9 @@ impl Clone for Cat {
     }
 }
 impl ByteRepr for Cat {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {}
     fn from_bytes(buf: &[u8]) -> Self {
         Self {}
diff --git a/tests/unit/out/refcount/push_emplace_back.rs b/tests/unit/out/refcount/push_emplace_back.rs
index 0ee8c04b..c6683ebb 100644
--- a/tests/unit/out/refcount/push_emplace_back.rs
+++ b/tests/unit/out/refcount/push_emplace_back.rs
@@ -19,6 +19,9 @@ impl Clone for Chunk {
     }
 }
 impl ByteRepr for Chunk {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.data.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -67,7 +70,23 @@ impl Clone for JPEGData {
         this
     }
 }
-impl ByteRepr for JPEGData {}
+impl ByteRepr for JPEGData {
+    fn byte_size() -> usize {
+        48
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.com_data.borrow()).to_bytes(&mut buf[0..24]);
+        (*self.app_data.borrow()).to_bytes(&mut buf[24..48]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            com_data: Rc::new(RefCell::new(<Vec<Value<Vec<u8>>>>::from_bytes(&buf[0..24]))),
+            app_data: Rc::new(RefCell::new(<Vec<Value<Vec<u8>>>>::from_bytes(
+                &buf[24..48],
+            ))),
+        }
+    }
+}
 pub fn push_param_0(dest: Ptr<Vec<Value<Vec<u8>>>>) {
     let dest: Value<Ptr<Vec<Value<Vec<u8>>>>> = Rc::new(RefCell::new(dest));
     ((*dest.borrow()).to_strong().as_pointer() as Ptr<Vec<Value<Vec<u8>>>>).with_mut(
diff --git a/tests/unit/out/refcount/random.rs b/tests/unit/out/refcount/random.rs
index 3b1057f8..aa0e5a31 100644
--- a/tests/unit/out/refcount/random.rs
+++ b/tests/unit/out/refcount/random.rs
@@ -82,6 +82,9 @@ impl Clone for X1 {
     }
 }
 impl ByteRepr for X1 {
+    fn byte_size() -> usize {
+        1
+    }
     fn to_bytes(&self, buf: &mut [u8]) {}
     fn from_bytes(buf: &[u8]) -> Self {
         Self {}
diff --git a/tests/unit/out/refcount/reinterpret_cast_struct.rs b/tests/unit/out/refcount/reinterpret_cast_struct.rs
index 9e2370a1..1c9e14b5 100644
--- a/tests/unit/out/refcount/reinterpret_cast_struct.rs
+++ b/tests/unit/out/refcount/reinterpret_cast_struct.rs
@@ -21,6 +21,9 @@ impl Clone for Point {
     }
 }
 impl ByteRepr for Point {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
         (*self.y.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/reinterpret_cast_struct_to_struct.rs b/tests/unit/out/refcount/reinterpret_cast_struct_to_struct.rs
index 0f065102..5b5d82c9 100644
--- a/tests/unit/out/refcount/reinterpret_cast_struct_to_struct.rs
+++ b/tests/unit/out/refcount/reinterpret_cast_struct_to_struct.rs
@@ -21,6 +21,9 @@ impl Clone for Point {
     }
 }
 impl ByteRepr for Point {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
         (*self.y.borrow()).to_bytes(&mut buf[4..8]);
@@ -47,6 +50,9 @@ impl Clone for Pair {
     }
 }
 impl ByteRepr for Pair {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.first.borrow()).to_bytes(&mut buf[0..4]);
         (*self.second.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/reserved_keywords.rs b/tests/unit/out/refcount/reserved_keywords.rs
index b670988f..5258cfab 100644
--- a/tests/unit/out/refcount/reserved_keywords.rs
+++ b/tests/unit/out/refcount/reserved_keywords.rs
@@ -93,6 +93,9 @@ impl Clone for S {
     }
 }
 impl ByteRepr for S {
+    fn byte_size() -> usize {
+        152
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.as_.borrow()).to_bytes(&mut buf[0..4]);
         (*self.async_.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/static_var_in_class.rs b/tests/unit/out/refcount/static_var_in_class.rs
index 35e012e7..d08a4f63 100644
--- a/tests/unit/out/refcount/static_var_in_class.rs
+++ b/tests/unit/out/refcount/static_var_in_class.rs
@@ -23,6 +23,9 @@ impl Clone for C {
     }
 }
 impl ByteRepr for C {
+    fn byte_size() -> usize {
+        1
+    }
     fn to_bytes(&self, buf: &mut [u8]) {}
     fn from_bytes(buf: &[u8]) -> Self {
         Self {}
@@ -40,6 +43,9 @@ impl Clone for S {
     }
 }
 impl ByteRepr for S {
+    fn byte_size() -> usize {
+        1
+    }
     fn to_bytes(&self, buf: &mut [u8]) {}
     fn from_bytes(buf: &[u8]) -> Self {
         Self {}
diff --git a/tests/unit/out/refcount/struct_ctor.rs b/tests/unit/out/refcount/struct_ctor.rs
index d5a4c660..430fd275 100644
--- a/tests/unit/out/refcount/struct_ctor.rs
+++ b/tests/unit/out/refcount/struct_ctor.rs
@@ -40,6 +40,9 @@ impl Clone for StructWithCtor {
     }
 }
 impl ByteRepr for StructWithCtor {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x1_.borrow()).to_bytes(&mut buf[0..4]);
         (*self.x2_.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/struct_ptr.rs b/tests/unit/out/refcount/struct_ptr.rs
index 4defc67a..beb54800 100644
--- a/tests/unit/out/refcount/struct_ptr.rs
+++ b/tests/unit/out/refcount/struct_ptr.rs
@@ -19,6 +19,9 @@ impl Clone for XX {
     }
 }
 impl ByteRepr for XX {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
     }
diff --git a/tests/unit/out/refcount/typedef-anon-struct.rs b/tests/unit/out/refcount/typedef-anon-struct.rs
index 251d05d8..80e81458 100644
--- a/tests/unit/out/refcount/typedef-anon-struct.rs
+++ b/tests/unit/out/refcount/typedef-anon-struct.rs
@@ -21,6 +21,9 @@ impl Clone for Outer_RunInfo {
     }
 }
 impl ByteRepr for Outer_RunInfo {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.block_idx.borrow()).to_bytes(&mut buf[0..4]);
         (*self.num_extra_zero_runs.borrow()).to_bytes(&mut buf[4..8]);
@@ -44,7 +47,19 @@ impl Clone for Outer {
         this
     }
 }
-impl ByteRepr for Outer {}
+impl ByteRepr for Outer {
+    fn byte_size() -> usize {
+        24
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.runs.borrow()).to_bytes(&mut buf[0..24]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            runs: Rc::new(RefCell::new(<Vec<Outer_RunInfo>>::from_bytes(&buf[0..24]))),
+        }
+    }
+}
 pub fn main() {
     std::process::exit(main_0());
 }
diff --git a/tests/unit/out/refcount/unique_ptr.rs b/tests/unit/out/refcount/unique_ptr.rs
index 9221a605..9d4eb0eb 100644
--- a/tests/unit/out/refcount/unique_ptr.rs
+++ b/tests/unit/out/refcount/unique_ptr.rs
@@ -15,7 +15,19 @@ impl SafePointer {
         (*(*self.ptr.borrow_mut()).as_ref().unwrap().borrow_mut()).prefix_inc();
     }
 }
-impl ByteRepr for SafePointer {}
+impl ByteRepr for SafePointer {
+    fn byte_size() -> usize {
+        8
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.ptr.borrow()).to_bytes(&mut buf[0..8]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            ptr: Rc::new(RefCell::new(<Option<Value<i32>>>::from_bytes(&buf[0..8]))),
+        }
+    }
+}
 #[derive(Default)]
 pub struct Pair {
     pub x: Value<i32>,
@@ -31,6 +43,9 @@ impl Clone for Pair {
     }
 }
 impl ByteRepr for Pair {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
         (*self.y.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/unique_ptr_const_deref.rs b/tests/unit/out/refcount/unique_ptr_const_deref.rs
index ee468020..8763aa17 100644
--- a/tests/unit/out/refcount/unique_ptr_const_deref.rs
+++ b/tests/unit/out/refcount/unique_ptr_const_deref.rs
@@ -10,7 +10,19 @@ use std::rc::{Rc, Weak};
 pub struct Holder {
     pub val: Value<Option<Value<i32>>>,
 }
-impl ByteRepr for Holder {}
+impl ByteRepr for Holder {
+    fn byte_size() -> usize {
+        8
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.val.borrow()).to_bytes(&mut buf[0..8]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            val: Rc::new(RefCell::new(<Option<Value<i32>>>::from_bytes(&buf[0..8]))),
+        }
+    }
+}
 pub fn read_val_0(h: Ptr<Holder>) -> i32 {
     let h: Value<Ptr<Holder>> = Rc::new(RefCell::new(h));
     return (*(*(*(*h.borrow()).upgrade().deref()).val.borrow())
diff --git a/tests/unit/out/refcount/unique_ptr_nested.rs b/tests/unit/out/refcount/unique_ptr_nested.rs
index 94cfb1d5..73a07682 100644
--- a/tests/unit/out/refcount/unique_ptr_nested.rs
+++ b/tests/unit/out/refcount/unique_ptr_nested.rs
@@ -21,6 +21,9 @@ impl Clone for Inner {
     }
 }
 impl ByteRepr for Inner {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
         (*self.y.borrow()).to_bytes(&mut buf[4..8]);
@@ -36,7 +39,19 @@ impl ByteRepr for Inner {
 pub struct Outer {
     pub inner: Value<Option<Value<Inner>>>,
 }
-impl ByteRepr for Outer {}
+impl ByteRepr for Outer {
+    fn byte_size() -> usize {
+        8
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.inner.borrow()).to_bytes(&mut buf[0..8]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            inner: Rc::new(RefCell::new(<Option<Value<Inner>>>::from_bytes(&buf[0..8]))),
+        }
+    }
+}
 pub fn main() {
     std::process::exit(main_0());
 }
diff --git a/tests/unit/out/refcount/unique_ptr_struct.rs b/tests/unit/out/refcount/unique_ptr_struct.rs
index ec65ca5b..bc8381b7 100644
--- a/tests/unit/out/refcount/unique_ptr_struct.rs
+++ b/tests/unit/out/refcount/unique_ptr_struct.rs
@@ -21,6 +21,9 @@ impl Clone for Point {
     }
 }
 impl ByteRepr for Point {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
         (*self.y.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/va_arg_struct_ctx.rs b/tests/unit/out/refcount/va_arg_struct_ctx.rs
index 37effcea..b6b031f5 100644
--- a/tests/unit/out/refcount/va_arg_struct_ctx.rs
+++ b/tests/unit/out/refcount/va_arg_struct_ctx.rs
@@ -12,6 +12,9 @@ pub struct context {
     pub last_error: Value<i32>,
 }
 impl ByteRepr for context {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.verbose.borrow()).to_bytes(&mut buf[0..4]);
         (*self.last_error.borrow()).to_bytes(&mut buf[4..8]);
diff --git a/tests/unit/out/refcount/void_cast.rs b/tests/unit/out/refcount/void_cast.rs
index aa18bf00..f8b0af11 100644
--- a/tests/unit/out/refcount/void_cast.rs
+++ b/tests/unit/out/refcount/void_cast.rs
@@ -22,7 +22,19 @@ impl Clone for NonTrivial {
         this
     }
 }
-impl ByteRepr for NonTrivial {}
+impl ByteRepr for NonTrivial {
+    fn byte_size() -> usize {
+        24
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.data.borrow()).to_bytes(&mut buf[0..24]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            data: Rc::new(RefCell::new(<Vec<i32>>::from_bytes(&buf[0..24]))),
+        }
+    }
+}
 pub fn unused_ref_param_1(x: Ptr<NonTrivial>) {
     (*x.upgrade().deref()).clone();
 }
@@ -50,6 +62,9 @@ impl Clone for Holder {
     }
 }
 impl ByteRepr for Holder {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.field.borrow()).to_bytes(&mut buf[0..4]);
     }

From 5af65da6bde510f669d8abf74019e3f04b843ed0 Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Thu, 25 Jun 2026 15:13:34 +0100
Subject: [PATCH 06/15] Add panic default implementations

---
 libcc2rs/src/reinterpret.rs | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/libcc2rs/src/reinterpret.rs b/libcc2rs/src/reinterpret.rs
index c554814f..1d428a28 100644
--- a/libcc2rs/src/reinterpret.rs
+++ b/libcc2rs/src/reinterpret.rs
@@ -8,16 +8,25 @@ pub trait ByteRepr: 'static {
     where
         Self: Sized,
     {
-        std::mem::size_of::<Self>()
+        panic!(
+            "byte_size is not implemented for {}",
+            std::any::type_name::<Self>()
+        )
     }
     fn to_bytes(&self, _buf: &mut [u8]) {
-        panic!("ByteRepr not supported for this type");
+        panic!(
+            "to_bytes is not implemented for {}",
+            std::any::type_name::<Self>()
+        )
     }
     fn from_bytes(_buf: &[u8]) -> Self
     where
         Self: Sized,
     {
-        panic!("ByteRepr not supported for this type");
+        panic!(
+            "from_bytes is not implemented for {}",
+            std::any::type_name::<Self>()
+        )
     }
 }
 

From 8084fc99591c0205151e9b995babbc96384523cc Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Thu, 25 Jun 2026 15:13:50 +0100
Subject: [PATCH 07/15] Implement byte_size for primitives

---
 libcc2rs/src/reinterpret.rs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/libcc2rs/src/reinterpret.rs b/libcc2rs/src/reinterpret.rs
index 1d428a28..b496f8b2 100644
--- a/libcc2rs/src/reinterpret.rs
+++ b/libcc2rs/src/reinterpret.rs
@@ -33,6 +33,10 @@ pub trait ByteRepr: 'static {
 macro_rules! impl_byte_repr {
     ($ty:ty) => {
         impl ByteRepr for $ty {
+            #[inline]
+            fn byte_size() -> usize {
+                std::mem::size_of::<$ty>()
+            }
             #[inline]
             fn to_bytes(&self, buf: &mut [u8]) {
                 buf.copy_from_slice(&self.to_ne_bytes());
@@ -61,6 +65,10 @@ impl_byte_repr!(f32);
 impl_byte_repr!(f64);
 
 impl ByteRepr for bool {
+    #[inline]
+    fn byte_size() -> usize {
+        1
+    }
     #[inline]
     fn to_bytes(&self, buf: &mut [u8]) {
         buf[0] = *self as u8;

From 532c0b58e1261b6306fd6d2076e2cc1df8740c3a Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Thu, 25 Jun 2026 16:00:54 +0100
Subject: [PATCH 08/15] Allow enums to have byterepr

---
 cpp2rust/converter/converter_lib.cpp          |  5 +-
 libcc2rs/src/rc.rs                            | 44 +++++++--------
 tests/unit/out/refcount/anonymous_enum.rs     | 56 ++++++++++++++++++-
 tests/unit/out/refcount/anonymous_enum_c.rs   | 56 ++++++++++++++++++-
 tests/unit/out/refcount/c_struct.rs           | 26 ++++++++-
 .../out/refcount/enum_default_in_static.rs    |  3 +
 6 files changed, 161 insertions(+), 29 deletions(-)

diff --git a/cpp2rust/converter/converter_lib.cpp b/cpp2rust/converter/converter_lib.cpp
index 4c4901a4..3b4a795c 100644
--- a/cpp2rust/converter/converter_lib.cpp
+++ b/cpp2rust/converter/converter_lib.cpp
@@ -201,10 +201,7 @@ bool IsMut(clang::QualType qual_type) {
 }
 
 bool TypeImplementsByteRepr(clang::QualType qt) {
-  if (qt->isEnumeralType()) {
-    return false;
-  }
-  if (qt->isIntegerType() || qt->isFloatingType()) {
+  if (qt->isIntegerType() || qt->isFloatingType() || qt->isEnumeralType()) {
     return true;
   }
   if (const auto *arr = qt->getAsArrayTypeUnsafe()) {
diff --git a/libcc2rs/src/rc.rs b/libcc2rs/src/rc.rs
index 6a643d6f..ac09c80c 100644
--- a/libcc2rs/src/rc.rs
+++ b/libcc2rs/src/rc.rs
@@ -84,8 +84,8 @@ impl<T> fmt::Debug for PtrKind<T> {
             PtrKind::HeapSingle(w) => write!(f, "HeapSingle({:?})", w.as_ptr()),
             PtrKind::StackArray(w) => write!(f, "StackArray({:?})", w.as_ptr()),
             PtrKind::HeapArray(w) => write!(f, "HeapArray({:?})", w.as_ptr()),
-            PtrKind::Reinterpreted(view) => {
-                write!(f, "Reinterpreted(0x{:x})", view.alloc.address())
+            PtrKind::Reinterpreted(data) => {
+                write!(f, "Reinterpreted(0x{:x})", data.alloc.address())
             }
         }
     }
@@ -100,7 +100,7 @@ impl<T> Clone for PtrKind<T> {
             PtrKind::HeapSingle(weak) => PtrKind::HeapSingle(weak.clone()),
             PtrKind::StackArray(weak) => PtrKind::StackArray(weak.clone()),
             PtrKind::HeapArray(weak) => PtrKind::HeapArray(weak.clone()),
-            PtrKind::Reinterpreted(view) => PtrKind::Reinterpreted(Rc::clone(view)),
+            PtrKind::Reinterpreted(data) => PtrKind::Reinterpreted(Rc::clone(data)),
         }
     }
 }
@@ -112,7 +112,7 @@ impl<T> PtrKind<T> {
             PtrKind::StackSingle(w) | PtrKind::HeapSingle(w) => w.as_ptr() as usize,
             PtrKind::Vec(w) => w.as_ptr() as usize,
             PtrKind::StackArray(w) | PtrKind::HeapArray(w) => w.as_ptr() as usize,
-            PtrKind::Reinterpreted(view) => view.alloc.address(),
+            PtrKind::Reinterpreted(data) => data.alloc.address(),
         }
     }
 }
@@ -258,7 +258,7 @@ impl<T> Ptr<T> {
     #[inline]
     fn elem_step(&self) -> usize {
         match &self.kind {
-            PtrKind::Reinterpreted(view) => view.elem_byte_size,
+            PtrKind::Reinterpreted(data) => data.elem_byte_size,
             _ => 1,
         }
     }
@@ -272,7 +272,7 @@ impl<T> Ptr<T> {
             PtrKind::StackArray(weak) | PtrKind::HeapArray(weak) => {
                 weak.upgrade().expect("ub: dangling pointer").borrow().len()
             }
-            PtrKind::Reinterpreted(view) => view.alloc.total_byte_len() / view.elem_byte_size,
+            PtrKind::Reinterpreted(data) => data.alloc.total_byte_len() / data.elem_byte_size,
         }
     }
 
@@ -291,7 +291,7 @@ impl<T> Ptr<T> {
                 .expect("ub: dangling pointer")
                 .borrow()
                 .is_empty(),
-            PtrKind::Reinterpreted(view) => self.offset >= view.alloc.total_byte_len(),
+            PtrKind::Reinterpreted(data) => self.offset >= data.alloc.total_byte_len(),
         }
     }
 
@@ -346,8 +346,8 @@ impl<T> Ptr<T> {
                 rc: weak.upgrade().expect("ub: dangling pointer"),
                 offset: self.offset,
             },
-            PtrKind::Reinterpreted(view) => StrongPtr::Reinterpreted {
-                alloc: Rc::clone(&view.alloc),
+            PtrKind::Reinterpreted(data) => StrongPtr::Reinterpreted {
+                alloc: Rc::clone(&data.alloc),
                 byte_offset: self.offset,
                 cell: RefCell::new(None),
             },
@@ -372,10 +372,10 @@ impl<T> Ptr<T> {
                 let rc = weak.upgrade().expect("ub: dangling pointer");
                 rc.borrow_mut()[self.offset] = value;
             }
-            PtrKind::Reinterpreted(view) => {
+            PtrKind::Reinterpreted(data) => {
                 let mut buf = vec![0u8; T::byte_size()];
                 value.to_bytes(&mut buf);
-                view.alloc.write_bytes(self.offset, &buf);
+                data.alloc.write_bytes(self.offset, &buf);
             }
         }
     }
@@ -417,7 +417,7 @@ impl<T> Ptr<T> {
                 Rc::new(SliceOriginalAlloc { weak: weak.clone() }),
                 src_byte_off,
             ),
-            PtrKind::Reinterpreted(view) => (Rc::clone(&view.alloc), self.offset),
+            PtrKind::Reinterpreted(data) => (Rc::clone(&data.alloc), self.offset),
         };
 
         Ptr {
@@ -452,13 +452,13 @@ impl<T> Ptr<T> {
                 let mut borrow = rc.borrow_mut();
                 f(&mut borrow[self.offset])
             }
-            PtrKind::Reinterpreted(view) => {
+            PtrKind::Reinterpreted(data) => {
                 let mut buf = vec![0u8; T::byte_size()];
-                view.alloc.read_bytes(self.offset, &mut buf);
+                data.alloc.read_bytes(self.offset, &mut buf);
                 let mut val = T::from_bytes(&buf);
                 let ret = f(&mut val);
                 val.to_bytes(&mut buf);
-                view.alloc.write_bytes(self.offset, &buf);
+                data.alloc.write_bytes(self.offset, &buf);
                 ret
             }
         }
@@ -485,9 +485,9 @@ impl<T> Ptr<T> {
                 let borrow = rc.borrow();
                 f(&borrow[self.offset])
             }
-            PtrKind::Reinterpreted(view) => {
+            PtrKind::Reinterpreted(data) => {
                 let mut buf = vec![0u8; T::byte_size()];
-                view.alloc.read_bytes(self.offset, &mut buf);
+                data.alloc.read_bytes(self.offset, &mut buf);
                 let val = T::from_bytes(&buf);
                 f(&val)
             }
@@ -512,9 +512,9 @@ impl<T: Clone + ByteRepr> Ptr<T> {
             PtrKind::StackArray(ref weak) | PtrKind::HeapArray(ref weak) => {
                 weak.upgrade().expect("ub: dangling pointer").borrow()[self.offset].clone()
             }
-            PtrKind::Reinterpreted(ref view) => {
+            PtrKind::Reinterpreted(ref data) => {
                 let mut buf = vec![0u8; T::byte_size()];
-                view.alloc.read_bytes(self.offset, &mut buf);
+                data.alloc.read_bytes(self.offset, &mut buf);
                 T::from_bytes(&buf)
             }
         }
@@ -909,7 +909,7 @@ impl<T> fmt::Debug for Ptr<T> {
                 (Weak::as_ptr(w) as usize).wrapping_add(self.byte_offset())
             }
             PtrKind::Vec(w) => (Weak::as_ptr(w) as usize).wrapping_add(self.byte_offset()),
-            PtrKind::Reinterpreted(view) => view.alloc.address().wrapping_add(self.byte_offset()),
+            PtrKind::Reinterpreted(data) => data.alloc.address().wrapping_add(self.byte_offset()),
         };
         write!(f, "0x{:x}", addr)
     }
@@ -1005,9 +1005,9 @@ impl Ptr<u8> {
                 let raw = strong.borrow();
                 raw[start..end].to_vec()
             }
-            PtrKind::Reinterpreted(ref view) => {
+            PtrKind::Reinterpreted(ref data) => {
                 let mut buf = vec![0u8; end.wrapping_sub(start)];
-                view.alloc.read_bytes(start, &mut buf);
+                data.alloc.read_bytes(start, &mut buf);
                 buf
             }
         }
diff --git a/tests/unit/out/refcount/anonymous_enum.rs b/tests/unit/out/refcount/anonymous_enum.rs
index f63deffd..47298b56 100644
--- a/tests/unit/out/refcount/anonymous_enum.rs
+++ b/tests/unit/out/refcount/anonymous_enum.rs
@@ -22,6 +22,14 @@ impl From<i32> for anon_0 {
     }
 }
 libcc2rs::impl_enum_inc_dec!(anon_0);
+impl ByteRepr for anon_0 {
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self as i32).to_bytes(buf);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        <anon_0>::from(i32::from_bytes(buf))
+    }
+}
 #[derive(Clone, Copy, PartialEq, Debug, Default)]
 enum anon_1 {
     #[default]
@@ -38,6 +46,14 @@ impl From<i32> for anon_1 {
     }
 }
 libcc2rs::impl_enum_inc_dec!(anon_1);
+impl ByteRepr for anon_1 {
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self as i32).to_bytes(buf);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        <anon_1>::from(i32::from_bytes(buf))
+    }
+}
 #[derive(Default)]
 pub struct S {
     pub a: Value<i32>,
@@ -79,6 +95,14 @@ impl From<i32> for TdEnum {
     }
 }
 libcc2rs::impl_enum_inc_dec!(TdEnum);
+impl ByteRepr for TdEnum {
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self as i32).to_bytes(buf);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        <TdEnum>::from(i32::from_bytes(buf))
+    }
+}
 #[derive(Clone, Copy, PartialEq, Debug, Default)]
 enum anon_2 {
     #[default]
@@ -95,6 +119,14 @@ impl From<i32> for anon_2 {
     }
 }
 libcc2rs::impl_enum_inc_dec!(anon_2);
+impl ByteRepr for anon_2 {
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self as i32).to_bytes(buf);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        <anon_2>::from(i32::from_bytes(buf))
+    }
+}
 #[derive(Default)]
 pub struct WithAnonField {
     pub a: Value<i32>,
@@ -109,7 +141,21 @@ impl Clone for WithAnonField {
         this
     }
 }
-impl ByteRepr for WithAnonField {}
+impl ByteRepr for WithAnonField {
+    fn byte_size() -> usize {
+        8
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.a.borrow()).to_bytes(&mut buf[0..4]);
+        (*self.field.borrow()).to_bytes(&mut buf[4..8]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            a: Rc::new(RefCell::new(<i32>::from_bytes(&buf[0..4]))),
+            field: Rc::new(RefCell::new(<anon_2>::from_bytes(&buf[4..8]))),
+        }
+    }
+}
 pub fn main() {
     std::process::exit(main_0());
 }
@@ -130,6 +176,14 @@ fn main_0() -> i32 {
         }
     }
     libcc2rs::impl_enum_inc_dec!(anon_3);
+    impl ByteRepr for anon_3 {
+        fn to_bytes(&self, buf: &mut [u8]) {
+            (*self as i32).to_bytes(buf);
+        }
+        fn from_bytes(buf: &[u8]) -> Self {
+            <anon_3>::from(i32::from_bytes(buf))
+        }
+    };
     assert!(((anon_0::FIRST_A as i32) != (anon_0::FIRST_B as i32)));
     assert!(((anon_1::SECOND_A as i32) != (anon_1::SECOND_B as i32)));
     assert!(((anon_3::THIRD_A as i32) != (anon_3::THIRD_B as i32)));
diff --git a/tests/unit/out/refcount/anonymous_enum_c.rs b/tests/unit/out/refcount/anonymous_enum_c.rs
index 43dc943b..a851a2b5 100644
--- a/tests/unit/out/refcount/anonymous_enum_c.rs
+++ b/tests/unit/out/refcount/anonymous_enum_c.rs
@@ -22,6 +22,14 @@ impl From<i32> for anon_0 {
     }
 }
 libcc2rs::impl_enum_inc_dec!(anon_0);
+impl ByteRepr for anon_0 {
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self as i32).to_bytes(buf);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        <anon_0>::from(i32::from_bytes(buf))
+    }
+}
 #[derive(Clone, Copy, PartialEq, Debug, Default)]
 enum anon_1 {
     #[default]
@@ -38,6 +46,14 @@ impl From<i32> for anon_1 {
     }
 }
 libcc2rs::impl_enum_inc_dec!(anon_1);
+impl ByteRepr for anon_1 {
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self as i32).to_bytes(buf);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        <anon_1>::from(i32::from_bytes(buf))
+    }
+}
 #[derive(Default)]
 pub struct S {
     pub a: Value<i32>,
@@ -71,6 +87,14 @@ impl From<i32> for TdEnum_enum {
     }
 }
 libcc2rs::impl_enum_inc_dec!(TdEnum_enum);
+impl ByteRepr for TdEnum_enum {
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self as i32).to_bytes(buf);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        <TdEnum_enum>::from(i32::from_bytes(buf))
+    }
+}
 #[derive(Clone, Copy, PartialEq, Debug, Default)]
 enum anon_2 {
     #[default]
@@ -87,12 +111,34 @@ impl From<i32> for anon_2 {
     }
 }
 libcc2rs::impl_enum_inc_dec!(anon_2);
+impl ByteRepr for anon_2 {
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self as i32).to_bytes(buf);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        <anon_2>::from(i32::from_bytes(buf))
+    }
+}
 #[derive(Default)]
 pub struct WithAnonField {
     pub a: Value<i32>,
     pub field: Value<anon_2>,
 }
-impl ByteRepr for WithAnonField {}
+impl ByteRepr for WithAnonField {
+    fn byte_size() -> usize {
+        8
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.a.borrow()).to_bytes(&mut buf[0..4]);
+        (*self.field.borrow()).to_bytes(&mut buf[4..8]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            a: Rc::new(RefCell::new(<i32>::from_bytes(&buf[0..4]))),
+            field: Rc::new(RefCell::new(<anon_2>::from_bytes(&buf[4..8]))),
+        }
+    }
+}
 pub fn main() {
     std::process::exit(main_0());
 }
@@ -113,6 +159,14 @@ fn main_0() -> i32 {
         }
     }
     libcc2rs::impl_enum_inc_dec!(anon_3);
+    impl ByteRepr for anon_3 {
+        fn to_bytes(&self, buf: &mut [u8]) {
+            (*self as i32).to_bytes(buf);
+        }
+        fn from_bytes(buf: &[u8]) -> Self {
+            <anon_3>::from(i32::from_bytes(buf))
+        }
+    };
     assert!(((((anon_0::FIRST_A as i32) != (anon_0::FIRST_B as i32)) as i32) != 0));
     assert!(((((anon_1::SECOND_A as i32) != (anon_1::SECOND_B as i32)) as i32) != 0));
     assert!(((((anon_3::THIRD_A as i32) != (anon_3::THIRD_B as i32)) as i32) != 0));
diff --git a/tests/unit/out/refcount/c_struct.rs b/tests/unit/out/refcount/c_struct.rs
index a0985ec8..1214d4a9 100644
--- a/tests/unit/out/refcount/c_struct.rs
+++ b/tests/unit/out/refcount/c_struct.rs
@@ -70,6 +70,14 @@ impl From<i32> for Color {
     }
 }
 libcc2rs::impl_enum_inc_dec!(Color);
+impl ByteRepr for Color {
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self as i32).to_bytes(buf);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        <Color>::from(i32::from_bytes(buf))
+    }
+}
 #[derive(Default)]
 pub struct Inner {
     pub a: Value<i32>,
@@ -96,7 +104,23 @@ pub struct Container {
     pub color: Value<Color>,
     pub count: Value<i32>,
 }
-impl ByteRepr for Container {}
+impl ByteRepr for Container {
+    fn byte_size() -> usize {
+        16
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.inner.borrow()).to_bytes(&mut buf[0..8]);
+        (*self.color.borrow()).to_bytes(&mut buf[8..12]);
+        (*self.count.borrow()).to_bytes(&mut buf[12..16]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            inner: Rc::new(RefCell::new(<Inner>::from_bytes(&buf[0..8]))),
+            color: Rc::new(RefCell::new(<Color>::from_bytes(&buf[8..12]))),
+            count: Rc::new(RefCell::new(<i32>::from_bytes(&buf[12..16]))),
+        }
+    }
+}
 pub fn main() {
     std::process::exit(main_0());
 }
diff --git a/tests/unit/out/refcount/enum_default_in_static.rs b/tests/unit/out/refcount/enum_default_in_static.rs
index 0e6f4c29..866240a2 100644
--- a/tests/unit/out/refcount/enum_default_in_static.rs
+++ b/tests/unit/out/refcount/enum_default_in_static.rs
@@ -38,6 +38,9 @@ pub struct Config {
     pub mode: Value<Mode>,
 }
 impl ByteRepr for Config {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.count.borrow()).to_bytes(&mut buf[0..4]);
         (*self.mode.borrow()).to_bytes(&mut buf[4..8]);

From 0573f9cc7965a508fa7aa25b62ccf82e4ba8ecd3 Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Thu, 25 Jun 2026 17:07:45 +0100
Subject: [PATCH 09/15] Don't add ByteRepr for system header types

---
 cpp2rust/converter/converter_lib.cpp          |  4 ++
 .../out/refcount/array_of_noncopy_struct.rs   | 16 +------
 tests/unit/out/refcount/class_templates.rs    | 42 ++-----------------
 .../refcount/foreach_disjoint_field_borrow.rs | 16 +------
 tests/unit/out/refcount/huffman.rs            | 26 +-----------
 tests/unit/out/refcount/implicit_autoref.rs   | 14 +------
 tests/unit/out/refcount/kruskal.rs            | 42 +------------------
 tests/unit/out/refcount/push_emplace_back.rs  | 18 +-------
 .../unit/out/refcount/typedef-anon-struct.rs  | 14 +------
 tests/unit/out/refcount/unique_ptr.rs         | 14 +------
 .../out/refcount/unique_ptr_const_deref.rs    | 14 +------
 tests/unit/out/refcount/unique_ptr_nested.rs  | 14 +------
 tests/unit/out/refcount/void_cast.rs          | 14 +------
 13 files changed, 19 insertions(+), 229 deletions(-)

diff --git a/cpp2rust/converter/converter_lib.cpp b/cpp2rust/converter/converter_lib.cpp
index 3b4a795c..2eafb1c1 100644
--- a/cpp2rust/converter/converter_lib.cpp
+++ b/cpp2rust/converter/converter_lib.cpp
@@ -208,6 +208,10 @@ bool TypeImplementsByteRepr(clang::QualType qt) {
     return TypeImplementsByteRepr(arr->getElementType());
   }
   if (const auto *rd = qt->getAsRecordDecl()) {
+    if (rd->getASTContext().getSourceManager().isInSystemHeader(
+            rd->getLocation())) {
+      return false;
+    }
     if (rd->isUnion()) {
       return true;
     }
diff --git a/tests/unit/out/refcount/array_of_noncopy_struct.rs b/tests/unit/out/refcount/array_of_noncopy_struct.rs
index 0c91af6d..4af56349 100644
--- a/tests/unit/out/refcount/array_of_noncopy_struct.rs
+++ b/tests/unit/out/refcount/array_of_noncopy_struct.rs
@@ -20,21 +20,7 @@ impl Clone for NonCopy {
         this
     }
 }
-impl ByteRepr for NonCopy {
-    fn byte_size() -> usize {
-        32
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.data.borrow()).to_bytes(&mut buf[0..24]);
-        (*self.tag.borrow()).to_bytes(&mut buf[24..28]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            data: Rc::new(RefCell::new(<Vec<i32>>::from_bytes(&buf[0..24]))),
-            tag: Rc::new(RefCell::new(<i32>::from_bytes(&buf[24..28]))),
-        }
-    }
-}
+impl ByteRepr for NonCopy {}
 pub fn main() {
     std::process::exit(main_0());
 }
diff --git a/tests/unit/out/refcount/class_templates.rs b/tests/unit/out/refcount/class_templates.rs
index 183fbd41..3cbce86e 100644
--- a/tests/unit/out/refcount/class_templates.rs
+++ b/tests/unit/out/refcount/class_templates.rs
@@ -42,19 +42,7 @@ impl Clone for MyContainer_int_ {
         this
     }
 }
-impl ByteRepr for MyContainer_int_ {
-    fn byte_size() -> usize {
-        24
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.vec_.borrow()).to_bytes(&mut buf[0..24]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            vec_: Rc::new(RefCell::new(<Vec<i32>>::from_bytes(&buf[0..24]))),
-        }
-    }
-}
+impl ByteRepr for MyContainer_int_ {}
 #[derive(Default)]
 pub struct MyContainer_char_ {
     vec_: Value<Vec<u8>>,
@@ -91,19 +79,7 @@ impl Clone for MyContainer_char_ {
         this
     }
 }
-impl ByteRepr for MyContainer_char_ {
-    fn byte_size() -> usize {
-        24
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.vec_.borrow()).to_bytes(&mut buf[0..24]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            vec_: Rc::new(RefCell::new(<Vec<u8>>::from_bytes(&buf[0..24]))),
-        }
-    }
-}
+impl ByteRepr for MyContainer_char_ {}
 #[derive(Default)]
 pub struct MyContainer_float_ {
     vec_: Value<Vec<f32>>,
@@ -140,19 +116,7 @@ impl Clone for MyContainer_float_ {
         this
     }
 }
-impl ByteRepr for MyContainer_float_ {
-    fn byte_size() -> usize {
-        24
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.vec_.borrow()).to_bytes(&mut buf[0..24]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            vec_: Rc::new(RefCell::new(<Vec<f32>>::from_bytes(&buf[0..24]))),
-        }
-    }
-}
+impl ByteRepr for MyContainer_float_ {}
 pub fn main() {
     std::process::exit(main_0());
 }
diff --git a/tests/unit/out/refcount/foreach_disjoint_field_borrow.rs b/tests/unit/out/refcount/foreach_disjoint_field_borrow.rs
index 57c56051..66c9e892 100644
--- a/tests/unit/out/refcount/foreach_disjoint_field_borrow.rs
+++ b/tests/unit/out/refcount/foreach_disjoint_field_borrow.rs
@@ -20,21 +20,7 @@ impl Clone for S {
         this
     }
 }
-impl ByteRepr for S {
-    fn byte_size() -> usize {
-        32
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.v.borrow()).to_bytes(&mut buf[0..24]);
-        (*self.a.borrow()).to_bytes(&mut buf[24..28]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            v: Rc::new(RefCell::new(<Vec<i32>>::from_bytes(&buf[0..24]))),
-            a: Rc::new(RefCell::new(<i32>::from_bytes(&buf[24..28]))),
-        }
-    }
-}
+impl ByteRepr for S {}
 pub fn main() {
     std::process::exit(main_0());
 }
diff --git a/tests/unit/out/refcount/huffman.rs b/tests/unit/out/refcount/huffman.rs
index c36e85e0..f320d46a 100644
--- a/tests/unit/out/refcount/huffman.rs
+++ b/tests/unit/out/refcount/huffman.rs
@@ -200,31 +200,7 @@ impl MinHeap {
         }
     }
 }
-impl ByteRepr for MinHeap {
-    fn byte_size() -> usize {
-        32
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.size.borrow()).to_bytes(&mut buf[0..4]);
-        (*self.capacity.borrow()).to_bytes(&mut buf[4..8]);
-        (*self.arr.borrow()).to_bytes(&mut buf[8..16]);
-        (*self.next.borrow()).to_bytes(&mut buf[16..20]);
-        (*self.alloc.borrow()).to_bytes(&mut buf[24..32]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            size: Rc::new(RefCell::new(<i32>::from_bytes(&buf[0..4]))),
-            capacity: Rc::new(RefCell::new(<i32>::from_bytes(&buf[4..8]))),
-            arr: Rc::new(RefCell::new(
-                <Option<Value<Box<[Ptr<MinHeapNode>]>>>>::from_bytes(&buf[8..16]),
-            )),
-            next: Rc::new(RefCell::new(<i32>::from_bytes(&buf[16..20]))),
-            alloc: Rc::new(RefCell::new(
-                <Option<Value<Box<[MinHeapNode]>>>>::from_bytes(&buf[24..32]),
-            )),
-        }
-    }
-}
+impl ByteRepr for MinHeap {}
 pub fn AllocMinHeap_1(capacity: i32) -> Option<Value<MinHeap>> {
     let capacity: Value<i32> = Rc::new(RefCell::new(capacity));
     let minHeap: Value<Option<Value<MinHeap>>> =
diff --git a/tests/unit/out/refcount/implicit_autoref.rs b/tests/unit/out/refcount/implicit_autoref.rs
index bda4df7e..f9b022a4 100644
--- a/tests/unit/out/refcount/implicit_autoref.rs
+++ b/tests/unit/out/refcount/implicit_autoref.rs
@@ -18,19 +18,7 @@ impl Clone for Holder {
         this
     }
 }
-impl ByteRepr for Holder {
-    fn byte_size() -> usize {
-        24
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.v.borrow()).to_bytes(&mut buf[0..24]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            v: Rc::new(RefCell::new(<Vec<i32>>::from_bytes(&buf[0..24]))),
-        }
-    }
-}
+impl ByteRepr for Holder {}
 pub fn write_through_0(p: Ptr<i32>) {
     let p: Value<Ptr<i32>> = Rc::new(RefCell::new(p));
     (*p.borrow()).write(42);
diff --git a/tests/unit/out/refcount/kruskal.rs b/tests/unit/out/refcount/kruskal.rs
index e2e21b98..28978811 100644
--- a/tests/unit/out/refcount/kruskal.rs
+++ b/tests/unit/out/refcount/kruskal.rs
@@ -280,52 +280,14 @@ impl DisjointSet {
         }
     }
 }
-impl ByteRepr for DisjointSet {
-    fn byte_size() -> usize {
-        24
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.rank.borrow()).to_bytes(&mut buf[0..8]);
-        (*self.parent.borrow()).to_bytes(&mut buf[8..16]);
-        (*self.n.borrow()).to_bytes(&mut buf[16..20]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            rank: Rc::new(RefCell::new(<Option<Value<Box<[i32]>>>>::from_bytes(
-                &buf[0..8],
-            ))),
-            parent: Rc::new(RefCell::new(<Option<Value<Box<[i32]>>>>::from_bytes(
-                &buf[8..16],
-            ))),
-            n: Rc::new(RefCell::new(<i32>::from_bytes(&buf[16..20]))),
-        }
-    }
-}
+impl ByteRepr for DisjointSet {}
 #[derive(Default)]
 pub struct Graph {
     pub edges: Value<Option<Value<Box<[Edge]>>>>,
     pub V: Value<i32>,
     pub E: Value<i32>,
 }
-impl ByteRepr for Graph {
-    fn byte_size() -> usize {
-        16
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.edges.borrow()).to_bytes(&mut buf[0..8]);
-        (*self.V.borrow()).to_bytes(&mut buf[8..12]);
-        (*self.E.borrow()).to_bytes(&mut buf[12..16]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            edges: Rc::new(RefCell::new(<Option<Value<Box<[Edge]>>>>::from_bytes(
-                &buf[0..8],
-            ))),
-            V: Rc::new(RefCell::new(<i32>::from_bytes(&buf[8..12]))),
-            E: Rc::new(RefCell::new(<i32>::from_bytes(&buf[12..16]))),
-        }
-    }
-}
+impl ByteRepr for Graph {}
 pub fn MSTKruskal_2(graph: Ptr<Graph>) -> f64 {
     ({
         let _arr: Ptr<Option<Value<Box<[Edge]>>>> = (*graph.upgrade().deref()).edges.as_pointer();
diff --git a/tests/unit/out/refcount/push_emplace_back.rs b/tests/unit/out/refcount/push_emplace_back.rs
index c6683ebb..c4309f6f 100644
--- a/tests/unit/out/refcount/push_emplace_back.rs
+++ b/tests/unit/out/refcount/push_emplace_back.rs
@@ -70,23 +70,7 @@ impl Clone for JPEGData {
         this
     }
 }
-impl ByteRepr for JPEGData {
-    fn byte_size() -> usize {
-        48
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.com_data.borrow()).to_bytes(&mut buf[0..24]);
-        (*self.app_data.borrow()).to_bytes(&mut buf[24..48]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            com_data: Rc::new(RefCell::new(<Vec<Value<Vec<u8>>>>::from_bytes(&buf[0..24]))),
-            app_data: Rc::new(RefCell::new(<Vec<Value<Vec<u8>>>>::from_bytes(
-                &buf[24..48],
-            ))),
-        }
-    }
-}
+impl ByteRepr for JPEGData {}
 pub fn push_param_0(dest: Ptr<Vec<Value<Vec<u8>>>>) {
     let dest: Value<Ptr<Vec<Value<Vec<u8>>>>> = Rc::new(RefCell::new(dest));
     ((*dest.borrow()).to_strong().as_pointer() as Ptr<Vec<Value<Vec<u8>>>>).with_mut(
diff --git a/tests/unit/out/refcount/typedef-anon-struct.rs b/tests/unit/out/refcount/typedef-anon-struct.rs
index 80e81458..81475e04 100644
--- a/tests/unit/out/refcount/typedef-anon-struct.rs
+++ b/tests/unit/out/refcount/typedef-anon-struct.rs
@@ -47,19 +47,7 @@ impl Clone for Outer {
         this
     }
 }
-impl ByteRepr for Outer {
-    fn byte_size() -> usize {
-        24
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.runs.borrow()).to_bytes(&mut buf[0..24]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            runs: Rc::new(RefCell::new(<Vec<Outer_RunInfo>>::from_bytes(&buf[0..24]))),
-        }
-    }
-}
+impl ByteRepr for Outer {}
 pub fn main() {
     std::process::exit(main_0());
 }
diff --git a/tests/unit/out/refcount/unique_ptr.rs b/tests/unit/out/refcount/unique_ptr.rs
index 9d4eb0eb..8f570b48 100644
--- a/tests/unit/out/refcount/unique_ptr.rs
+++ b/tests/unit/out/refcount/unique_ptr.rs
@@ -15,19 +15,7 @@ impl SafePointer {
         (*(*self.ptr.borrow_mut()).as_ref().unwrap().borrow_mut()).prefix_inc();
     }
 }
-impl ByteRepr for SafePointer {
-    fn byte_size() -> usize {
-        8
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.ptr.borrow()).to_bytes(&mut buf[0..8]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            ptr: Rc::new(RefCell::new(<Option<Value<i32>>>::from_bytes(&buf[0..8]))),
-        }
-    }
-}
+impl ByteRepr for SafePointer {}
 #[derive(Default)]
 pub struct Pair {
     pub x: Value<i32>,
diff --git a/tests/unit/out/refcount/unique_ptr_const_deref.rs b/tests/unit/out/refcount/unique_ptr_const_deref.rs
index 8763aa17..ee468020 100644
--- a/tests/unit/out/refcount/unique_ptr_const_deref.rs
+++ b/tests/unit/out/refcount/unique_ptr_const_deref.rs
@@ -10,19 +10,7 @@ use std::rc::{Rc, Weak};
 pub struct Holder {
     pub val: Value<Option<Value<i32>>>,
 }
-impl ByteRepr for Holder {
-    fn byte_size() -> usize {
-        8
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.val.borrow()).to_bytes(&mut buf[0..8]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            val: Rc::new(RefCell::new(<Option<Value<i32>>>::from_bytes(&buf[0..8]))),
-        }
-    }
-}
+impl ByteRepr for Holder {}
 pub fn read_val_0(h: Ptr<Holder>) -> i32 {
     let h: Value<Ptr<Holder>> = Rc::new(RefCell::new(h));
     return (*(*(*(*h.borrow()).upgrade().deref()).val.borrow())
diff --git a/tests/unit/out/refcount/unique_ptr_nested.rs b/tests/unit/out/refcount/unique_ptr_nested.rs
index 73a07682..e1ad9181 100644
--- a/tests/unit/out/refcount/unique_ptr_nested.rs
+++ b/tests/unit/out/refcount/unique_ptr_nested.rs
@@ -39,19 +39,7 @@ impl ByteRepr for Inner {
 pub struct Outer {
     pub inner: Value<Option<Value<Inner>>>,
 }
-impl ByteRepr for Outer {
-    fn byte_size() -> usize {
-        8
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.inner.borrow()).to_bytes(&mut buf[0..8]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            inner: Rc::new(RefCell::new(<Option<Value<Inner>>>::from_bytes(&buf[0..8]))),
-        }
-    }
-}
+impl ByteRepr for Outer {}
 pub fn main() {
     std::process::exit(main_0());
 }
diff --git a/tests/unit/out/refcount/void_cast.rs b/tests/unit/out/refcount/void_cast.rs
index f8b0af11..0933260f 100644
--- a/tests/unit/out/refcount/void_cast.rs
+++ b/tests/unit/out/refcount/void_cast.rs
@@ -22,19 +22,7 @@ impl Clone for NonTrivial {
         this
     }
 }
-impl ByteRepr for NonTrivial {
-    fn byte_size() -> usize {
-        24
-    }
-    fn to_bytes(&self, buf: &mut [u8]) {
-        (*self.data.borrow()).to_bytes(&mut buf[0..24]);
-    }
-    fn from_bytes(buf: &[u8]) -> Self {
-        Self {
-            data: Rc::new(RefCell::new(<Vec<i32>>::from_bytes(&buf[0..24]))),
-        }
-    }
-}
+impl ByteRepr for NonTrivial {}
 pub fn unused_ref_param_1(x: Ptr<NonTrivial>) {
     (*x.upgrade().deref()).clone();
 }

From 32d916a57bf0ec81dca34ee60e46fbd9da97a0fd Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Thu, 25 Jun 2026 22:20:47 +0100
Subject: [PATCH 10/15] Ignore unions in ByteRepr for now

---
 cpp2rust/converter/converter_lib.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cpp2rust/converter/converter_lib.cpp b/cpp2rust/converter/converter_lib.cpp
index 2eafb1c1..6332cdba 100644
--- a/cpp2rust/converter/converter_lib.cpp
+++ b/cpp2rust/converter/converter_lib.cpp
@@ -213,7 +213,7 @@ bool TypeImplementsByteRepr(clang::QualType qt) {
       return false;
     }
     if (rd->isUnion()) {
-      return true;
+      return false;
     }
     for (const auto *field : rd->fields()) {
       if (!TypeImplementsByteRepr(field->getType())) {

From 96cd27033cdb1f1ee2adfc799e2760a22217a92a Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Thu, 25 Jun 2026 22:20:58 +0100
Subject: [PATCH 11/15] Update tests

---
 .../refcount/tag_vs_identifier_collision.rs   | 26 ++++++++++++++++++-
 .../out/refcount/union_tagged_struct_arms.rs  |  6 +++++
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/tests/unit/out/refcount/tag_vs_identifier_collision.rs b/tests/unit/out/refcount/tag_vs_identifier_collision.rs
index eccceda4..bf14ce14 100644
--- a/tests/unit/out/refcount/tag_vs_identifier_collision.rs
+++ b/tests/unit/out/refcount/tag_vs_identifier_collision.rs
@@ -38,6 +38,9 @@ pub struct widget {
     pub mode: Value<widget_enum>,
 }
 impl ByteRepr for widget {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.id.borrow()).to_bytes(&mut buf[0..4]);
         (*self.mode.borrow()).to_bytes(&mut buf[4..8]);
@@ -55,6 +58,9 @@ pub struct point_struct {
     pub y: Value<i32>,
 }
 impl ByteRepr for point_struct {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
         (*self.y.borrow()).to_bytes(&mut buf[4..8]);
@@ -147,6 +153,9 @@ pub struct Inner {
     pub tag_field: Value<i32>,
 }
 impl ByteRepr for Inner {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.tag_field.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -160,12 +169,27 @@ impl ByteRepr for Inner {
 pub struct Outer {
     pub field: Value<Inner>,
 }
-impl ByteRepr for Outer {}
+impl ByteRepr for Outer {
+    fn byte_size() -> usize {
+        4
+    }
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.field.borrow()).to_bytes(&mut buf[0..4]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            field: Rc::new(RefCell::new(<Inner>::from_bytes(&buf[0..4]))),
+        }
+    }
+}
 #[derive(Default)]
 pub struct Inner_struct {
     pub typedef_field: Value<i32>,
 }
 impl ByteRepr for Inner_struct {
+    fn byte_size() -> usize {
+        4
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.typedef_field.borrow()).to_bytes(&mut buf[0..4]);
     }
diff --git a/tests/unit/out/refcount/union_tagged_struct_arms.rs b/tests/unit/out/refcount/union_tagged_struct_arms.rs
index 37417848..4155c690 100644
--- a/tests/unit/out/refcount/union_tagged_struct_arms.rs
+++ b/tests/unit/out/refcount/union_tagged_struct_arms.rs
@@ -47,6 +47,9 @@ pub struct anon_2 {
     pub step: Value<u8>,
 }
 impl ByteRepr for anon_2 {
+    fn byte_size() -> usize {
+        16
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.lo.borrow()).to_bytes(&mut buf[0..4]);
         (*self.hi.borrow()).to_bytes(&mut buf[4..8]);
@@ -71,6 +74,9 @@ pub struct anon_3 {
     pub width: Value<i32>,
 }
 impl ByteRepr for anon_3 {
+    fn byte_size() -> usize {
+        40
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.lo.borrow()).to_bytes(&mut buf[0..8]);
         (*self.hi.borrow()).to_bytes(&mut buf[8..16]);

From 34020423ab50e9a69ad93c6d5d5e849d69fe472e Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Tue, 23 Jun 2026 16:03:03 +0100
Subject: [PATCH 12/15] Memcpy a poitner to a struct through ErasedPtr

---
 libcc2rs/src/fn_ptr.rs | 16 +++-----
 libcc2rs/src/rc.rs     | 90 +++++++++---------------------------------
 2 files changed, 23 insertions(+), 83 deletions(-)

diff --git a/libcc2rs/src/fn_ptr.rs b/libcc2rs/src/fn_ptr.rs
index 2ccc150e..e7152279 100644
--- a/libcc2rs/src/fn_ptr.rs
+++ b/libcc2rs/src/fn_ptr.rs
@@ -6,7 +6,7 @@ use std::marker::PhantomData;
 use std::ops::Deref;
 use std::rc::Rc;
 
-use crate::rc::{AnyPtr, ErasedPtr};
+use crate::rc::{AnyPtr, ErasedPtr, Ptr};
 use crate::reinterpret::ByteRepr;
 
 pub trait FnAddr {
@@ -146,20 +146,14 @@ impl<T> Eq for FnPtr<T> {}
 impl<T: 'static> ByteRepr for FnPtr<T> {}
 
 impl<T: 'static> ErasedPtr for FnPtr<T> {
-    fn pointee_type_id(&self) -> TypeId {
-        TypeId::of::<T>()
-    }
-    fn memcpy(&self, _src: &dyn ErasedPtr, _len: usize) {
-        panic!("memcpy not supported on fn pointer");
+    fn as_bytes(&self) -> Ptr<u8> {
+        panic!("byte view not supported on fn pointer");
     }
     fn as_any(&self) -> &dyn Any {
         self
     }
-    fn equals(&self, other: &dyn ErasedPtr) -> Option<bool> {
-        if self.pointee_type_id() != other.pointee_type_id() {
-            return None;
-        }
-        other.as_any().downcast_ref::<FnPtr<T>>().map(|o| self == o)
+    fn equals(&self, other: &dyn ErasedPtr) -> bool {
+        other.as_any().downcast_ref::<FnPtr<T>>() == Some(self)
     }
     fn is_null(&self) -> bool {
         FnPtr::is_null(self)
diff --git a/libcc2rs/src/rc.rs b/libcc2rs/src/rc.rs
index ac09c80c..ce8bf501 100644
--- a/libcc2rs/src/rc.rs
+++ b/libcc2rs/src/rc.rs
@@ -1042,49 +1042,33 @@ impl Ptr<u8> {
 }
 
 pub(crate) trait ErasedPtr: std::any::Any {
-    fn pointee_type_id(&self) -> std::any::TypeId;
-    fn memcpy(&self, src: &dyn ErasedPtr, len: usize);
+    fn as_bytes(&self) -> Ptr<u8>;
     fn as_any(&self) -> &dyn std::any::Any;
-    fn equals(&self, other: &dyn ErasedPtr) -> Option<bool>;
+    fn equals(&self, other: &dyn ErasedPtr) -> bool;
     fn is_null(&self) -> bool;
 }
 
+impl PartialEq for dyn ErasedPtr {
+    fn eq(&self, other: &Self) -> bool {
+        self.equals(other)
+    }
+}
+
 impl<T> ErasedPtr for Ptr<T>
 where
     T: ByteRepr + 'static,
     Ptr<T>: PartialEq,
 {
-    fn pointee_type_id(&self) -> std::any::TypeId {
-        std::any::TypeId::of::<T>()
-    }
-
-    fn memcpy(&self, src: &dyn ErasedPtr, len: usize) {
-        if self.pointee_type_id() != src.pointee_type_id() {
-            panic!("memcpy: type mismatch");
-        }
-        let src_ptr = src
-            .as_any()
-            .downcast_ref::<Ptr<T>>()
-            .expect("memcpy: downcast to Ptr<T> failed");
-        let dst_bytes: Ptr<u8> = self.reinterpret_cast();
-        let src_bytes: Ptr<u8> = src_ptr.reinterpret_cast();
-        dst_bytes.memcpy(&src_bytes, len);
+    fn as_bytes(&self) -> Ptr<u8> {
+        self.reinterpret_cast::<u8>()
     }
 
     fn as_any(&self) -> &dyn std::any::Any {
         self
     }
 
-    fn equals(&self, other: &dyn ErasedPtr) -> Option<bool> {
-        if self.pointee_type_id() != other.pointee_type_id() {
-            return None;
-        }
-
-        if let Some(other_ptr) = other.as_any().downcast_ref::<Ptr<T>>() {
-            return Some(self == other_ptr);
-        }
-
-        None
+    fn equals(&self, other: &dyn ErasedPtr) -> bool {
+        other.as_any().downcast_ref::<Ptr<T>>() == Some(self)
     }
 
     fn is_null(&self) -> bool {
@@ -1118,66 +1102,28 @@ impl AnyPtr {
         }
         self.ptr.as_any().downcast_ref::<Ptr<T>>().cloned()
     }
-
-    pub fn reinterpret_cast<T: ByteRepr>(&self) -> Ptr<T> {
-        macro_rules! try_src {
-            ($ty:ty) => {{
-                if let Some(p) = self.cast::<$ty>() {
-                    return p.reinterpret_cast::<T>();
-                }
-                if let Some(pv) = self.cast::<Vec<$ty>>() {
-                    return pv.reinterpret_cast::<T>();
-                }
-            }};
-        }
-
-        try_src!(u8);
-        try_src!(i8);
-        try_src!(u16);
-        try_src!(i16);
-        try_src!(u32);
-        try_src!(i32);
-        try_src!(u64);
-        try_src!(i64);
-        try_src!(usize);
-        try_src!(isize);
-
-        panic!("reinterpret_cast: unsupported AnyPtr source");
-    }
 }
 
 impl PartialEq for AnyPtr {
     fn eq(&self, other: &Self) -> bool {
-        let lhs: &dyn ErasedPtr = self.ptr.as_ref();
-        let rhs: &dyn ErasedPtr = other.ptr.as_ref();
-
-        lhs.equals(rhs).unwrap_or_default()
+        *self.ptr == *other.ptr
     }
 }
 
 impl AnyPtr {
     pub fn memcpy(&self, src: &AnyPtr, len: usize) {
-        let dst_erased = &*self.ptr;
-        let src_erased = &*src.ptr;
-
-        if dst_erased.pointee_type_id() == src_erased.pointee_type_id() {
-            dst_erased.memcpy(src_erased, len);
-            return;
-        }
-
-        let dst_u8: Ptr<u8> = self.reinterpret_cast();
-        let src_u8: Ptr<u8> = src.reinterpret_cast();
+        let dst_u8 = self.ptr.as_bytes();
+        let src_u8 = src.ptr.as_bytes();
         dst_u8.memcpy(&src_u8, len);
     }
 
     pub fn memset(&self, value: u8, num: usize) {
-        let dst_u8: Ptr<u8> = self.reinterpret_cast();
-        dst_u8.memset(value, num);
+        self.ptr.as_bytes().memset(value, num);
     }
 
     pub fn memcmp(&self, other: &AnyPtr, len: usize) -> i32 {
-        let a: Ptr<u8> = self.reinterpret_cast();
-        let b: Ptr<u8> = other.reinterpret_cast();
+        let a = self.ptr.as_bytes();
+        let b = other.ptr.as_bytes();
         a.memcmp(&b, len)
     }
 }

From fb7f030fe5e0a90cd9a6318d64ac1c6c171882dc Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Thu, 25 Jun 2026 14:49:53 +0100
Subject: [PATCH 13/15] Add memcpy_struct_bytes test

---
 tests/unit/memcpy_struct_bytes.c              | 23 ++++++++
 .../unit/out/refcount/memcpy_struct_bytes.rs  | 55 +++++++++++++++++++
 tests/unit/out/unsafe/memcpy_struct_bytes.rs  | 47 ++++++++++++++++
 3 files changed, 125 insertions(+)
 create mode 100644 tests/unit/memcpy_struct_bytes.c
 create mode 100644 tests/unit/out/refcount/memcpy_struct_bytes.rs
 create mode 100644 tests/unit/out/unsafe/memcpy_struct_bytes.rs

diff --git a/tests/unit/memcpy_struct_bytes.c b/tests/unit/memcpy_struct_bytes.c
new file mode 100644
index 00000000..ae767639
--- /dev/null
+++ b/tests/unit/memcpy_struct_bytes.c
@@ -0,0 +1,23 @@
+#include <assert.h>
+#include <stdint.h>
+#include <string.h>
+
+struct point {
+  int32_t x;
+  int32_t y;
+};
+
+int main(void) {
+  struct point src = {3, 7};
+
+  unsigned char buf[sizeof(struct point)];
+  memcpy(buf, &src, sizeof(buf));
+
+  struct point dst;
+  memcpy(&dst, buf, sizeof(dst));
+
+  assert(dst.x == 3);
+  assert(dst.y == 7);
+
+  return 0;
+}
diff --git a/tests/unit/out/refcount/memcpy_struct_bytes.rs b/tests/unit/out/refcount/memcpy_struct_bytes.rs
new file mode 100644
index 00000000..ada7f67a
--- /dev/null
+++ b/tests/unit/out/refcount/memcpy_struct_bytes.rs
@@ -0,0 +1,55 @@
+extern crate libcc2rs;
+use libcc2rs::*;
+use std::cell::RefCell;
+use std::collections::BTreeMap;
+use std::io::prelude::*;
+use std::io::{Read, Seek, Write};
+use std::os::fd::AsFd;
+use std::rc::{Rc, Weak};
+#[derive(Default)]
+pub struct point {
+    pub x: Value<i32>,
+    pub y: Value<i32>,
+}
+impl ByteRepr for point {
+    fn to_bytes(&self, buf: &mut [u8]) {
+        (*self.x.borrow()).to_bytes(&mut buf[0..4]);
+        (*self.y.borrow()).to_bytes(&mut buf[4..8]);
+    }
+    fn from_bytes(buf: &[u8]) -> Self {
+        Self {
+            x: Rc::new(RefCell::new(<i32>::from_bytes(&buf[0..4]))),
+            y: Rc::new(RefCell::new(<i32>::from_bytes(&buf[4..8]))),
+        }
+    }
+}
+pub fn main() {
+    std::process::exit(main_0());
+}
+fn main_0() -> i32 {
+    let src: Value<point> = Rc::new(RefCell::new(point {
+        x: Rc::new(RefCell::new(3)),
+        y: Rc::new(RefCell::new(7)),
+    }));
+    let buf: Value<Box<[u8]>> = Rc::new(RefCell::new(
+        (0..8).map(|_| <u8>::default()).collect::<Box<[u8]>>(),
+    ));
+    {
+        ((buf.as_pointer() as Ptr<u8>) as Ptr<u8>).to_any().memcpy(
+            &((src.as_pointer()) as Ptr<point>).to_any(),
+            ::std::mem::size_of::<[u8; 8]>() as usize,
+        );
+        ((buf.as_pointer() as Ptr<u8>) as Ptr<u8>).to_any().clone()
+    };
+    let dst: Value<point> = <Value<point>>::default();
+    {
+        ((dst.as_pointer()) as Ptr<point>).to_any().memcpy(
+            &((buf.as_pointer() as Ptr<u8>) as Ptr<u8>).to_any(),
+            ::std::mem::size_of::<point>() as usize,
+        );
+        ((dst.as_pointer()) as Ptr<point>).to_any().clone()
+    };
+    assert!(((((*(*dst.borrow()).x.borrow()) == 3) as i32) != 0));
+    assert!(((((*(*dst.borrow()).y.borrow()) == 7) as i32) != 0));
+    return 0;
+}
diff --git a/tests/unit/out/unsafe/memcpy_struct_bytes.rs b/tests/unit/out/unsafe/memcpy_struct_bytes.rs
new file mode 100644
index 00000000..110b0a87
--- /dev/null
+++ b/tests/unit/out/unsafe/memcpy_struct_bytes.rs
@@ -0,0 +1,47 @@
+extern crate libc;
+use libc::*;
+extern crate libcc2rs;
+use libcc2rs::*;
+use std::collections::BTreeMap;
+use std::io::{Read, Seek, Write};
+use std::os::fd::{AsFd, FromRawFd, IntoRawFd};
+use std::rc::Rc;
+#[repr(C)]
+#[derive(Copy, Clone, Default)]
+pub struct point {
+    pub x: i32,
+    pub y: i32,
+}
+pub fn main() {
+    unsafe {
+        std::process::exit(main_0() as i32);
+    }
+}
+unsafe fn main_0() -> i32 {
+    let mut src: point = point { x: 3, y: 7 };
+    let mut buf: [u8; 8] = [0_u8; 8];
+    {
+        if ::std::mem::size_of::<[u8; 8]>() != 0 {
+            ::std::ptr::copy_nonoverlapping(
+                ((&mut src as *mut point) as *const point as *const ::libc::c_void),
+                (buf.as_mut_ptr() as *mut u8 as *mut ::libc::c_void),
+                ::std::mem::size_of::<[u8; 8]>() as usize,
+            )
+        }
+        (buf.as_mut_ptr() as *mut u8 as *mut ::libc::c_void)
+    };
+    let mut dst: point = <point>::default();
+    {
+        if ::std::mem::size_of::<point>() != 0 {
+            ::std::ptr::copy_nonoverlapping(
+                (buf.as_mut_ptr() as *const u8 as *const ::libc::c_void),
+                ((&mut dst as *mut point) as *mut point as *mut ::libc::c_void),
+                ::std::mem::size_of::<point>() as usize,
+            )
+        }
+        ((&mut dst as *mut point) as *mut point as *mut ::libc::c_void)
+    };
+    assert!(((((dst.x) == (3)) as i32) != 0));
+    assert!(((((dst.y) == (7)) as i32) != 0));
+    return 0;
+}

From e4bb83ea93687b3485e1280cfa1ee756379dfb13 Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Thu, 25 Jun 2026 17:49:02 +0100
Subject: [PATCH 14/15] Update tests

---
 tests/unit/out/refcount/memcpy_struct_bytes.rs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tests/unit/out/refcount/memcpy_struct_bytes.rs b/tests/unit/out/refcount/memcpy_struct_bytes.rs
index ada7f67a..d233b346 100644
--- a/tests/unit/out/refcount/memcpy_struct_bytes.rs
+++ b/tests/unit/out/refcount/memcpy_struct_bytes.rs
@@ -12,6 +12,9 @@ pub struct point {
     pub y: Value<i32>,
 }
 impl ByteRepr for point {
+    fn byte_size() -> usize {
+        8
+    }
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.x.borrow()).to_bytes(&mut buf[0..4]);
         (*self.y.borrow()).to_bytes(&mut buf[4..8]);
@@ -45,7 +48,7 @@ fn main_0() -> i32 {
     {
         ((dst.as_pointer()) as Ptr<point>).to_any().memcpy(
             &((buf.as_pointer() as Ptr<u8>) as Ptr<u8>).to_any(),
-            ::std::mem::size_of::<point>() as usize,
+            8usize as usize,
         );
         ((dst.as_pointer()) as Ptr<point>).to_any().clone()
     };

From 48d69080873dceca3afe4fbcc40a73121690eec0 Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Mon, 29 Jun 2026 14:08:13 +0100
Subject: [PATCH 15/15] Trigger CI