From 0857fb51030360280822b51aedcd2251a68beb92 Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Wed, 27 May 2026 10:29:50 +0100
Subject: [PATCH 1/2] Fix collision of anonymous structs from different
 functions

---
 cpp2rust/converter/converter_lib.cpp          | 39 +++-------
 cpp2rust/converter/converter_lib.h            |  2 -
 cpp2rust/converter/mapper.cpp                 | 14 +---
 tests/unit/local_anon_struct_collision.c      | 27 +++++++
 tests/unit/out/refcount/anonymous-struct.rs   | 74 +++++++++----------
 tests/unit/out/refcount/anonymous-struct_c.rs | 54 +++++++-------
 .../refcount/local_anon_struct_collision.rs   | 62 ++++++++++++++++
 tests/unit/out/unsafe/anonymous-struct.rs     | 44 +++++------
 tests/unit/out/unsafe/anonymous-struct_c.rs   | 40 +++++-----
 .../out/unsafe/local_anon_struct_collision.rs | 42 +++++++++++
 .../unit/out/unsafe/union_addrof_external.rs  | 15 ++--
 tests/unit/out/unsafe/union_cross_arm_cast.rs |  6 +-
 .../unit/out/unsafe/union_field_alignment.rs  |  6 +-
 tests/unit/out/unsafe/union_memset_memcpy.rs  |  6 +-
 tests/unit/out/unsafe/union_nested.rs         | 12 +--
 .../unit/out/unsafe/union_struct_dual_use.rs  |  6 +-
 .../unit/out/unsafe/union_tagged_many_arms.rs |  6 +-
 tests/unit/out/unsafe/union_tagged_simple.rs  |  6 +-
 .../out/unsafe/union_tagged_struct_arms.rs    | 22 +++---
 .../out/unsafe/union_void_ptr_sized_deref.rs  | 14 ++--
 20 files changed, 299 insertions(+), 198 deletions(-)
 create mode 100644 tests/unit/local_anon_struct_collision.c
 create mode 100644 tests/unit/out/refcount/local_anon_struct_collision.rs
 create mode 100644 tests/unit/out/unsafe/local_anon_struct_collision.rs

diff --git a/cpp2rust/converter/converter_lib.cpp b/cpp2rust/converter/converter_lib.cpp
index 051aed2d..a8bf076c 100644
--- a/cpp2rust/converter/converter_lib.cpp
+++ b/cpp2rust/converter/converter_lib.cpp
@@ -328,25 +328,6 @@ unsigned GetArraySize(clang::QualType array_type) {
   return constant_array_ty->getSize().getZExtValue();
 }
 
-unsigned GetAnonIndex(const clang::NamedDecl *decl) {
-  if (auto *parent =
-          clang::dyn_cast<clang::RecordDecl>(decl->getDeclContext())) {
-    unsigned counter = 0;
-    for (auto *d : parent->decls()) {
-      if (d == decl) {
-        return counter;
-      }
-      auto *named = clang::dyn_cast<clang::NamedDecl>(d);
-      if (named && named->getKind() == decl->getKind() &&
-          named->getName().empty()) {
-        counter++;
-      }
-    }
-    return counter;
-  }
-  return 0;
-}
-
 static std::string GetLocationID(const clang::Decl *decl) {
   return GetFileName(decl) + std::to_string(GetLineNumber(decl)) +
          std::to_string(GetColumnNumber(decl));
@@ -373,15 +354,19 @@ std::string GetNamedDeclAsString(const clang::NamedDecl *decl) {
   auto name = decl->getDeclName().isIdentifier() ? decl->getName().str()
                                                  : decl->getNameAsString();
 
-  // Anonymous record field
-  if (auto *field = clang::dyn_cast<clang::FieldDecl>(decl);
-      field && name.empty()) {
-    const clang::NamedDecl *target = field;
-    if (auto *record = field->getType()->getAsRecordDecl();
-        record && !record->getIdentifier()) {
-      target = record;
+  // Anonymous record
+  if (name.empty() && (clang::isa<clang::RecordDecl>(decl) ||
+                       clang::isa<clang::FieldDecl>(decl))) {
+    const clang::NamedDecl *target = decl;
+    if (auto *field = clang::dyn_cast<clang::FieldDecl>(decl)) {
+      if (auto *record = field->getType()->getAsRecordDecl();
+          record && !record->getIdentifier()) {
+        target = record;
+      }
     }
-    return std::format("anon_{}", GetAnonIndex(target));
+    return std::format(
+        "anon_{}", type_mapping.try_emplace(GetID(target), type_mapping.size())
+                       .first->second);
   }
 
   if (auto *fn = clang::dyn_cast<clang::FunctionDecl>(decl)) {
diff --git a/cpp2rust/converter/converter_lib.h b/cpp2rust/converter/converter_lib.h
index c208ea1c..cae8afbf 100644
--- a/cpp2rust/converter/converter_lib.h
+++ b/cpp2rust/converter/converter_lib.h
@@ -87,8 +87,6 @@ std::string GetID(const clang::Decl *decl);
 
 std::string GetNamedDeclAsString(const clang::NamedDecl *decl);
 
-unsigned GetAnonIndex(const clang::NamedDecl *decl);
-
 const char *AccessSpecifierAsString(clang::AccessSpecifier spec);
 
 template <class T> llvm::SmallString<16> GetNumAsString(const T &num) {
diff --git a/cpp2rust/converter/mapper.cpp b/cpp2rust/converter/mapper.cpp
index 8a7109a4..fc8779fa 100644
--- a/cpp2rust/converter/mapper.cpp
+++ b/cpp2rust/converter/mapper.cpp
@@ -571,18 +571,6 @@ std::string normalizeTranslationRule(std::string rule) {
   return rule;
 }
 
-static std::string synthesizeAnonRecordName(const clang::RecordDecl *record) {
-  std::string parent_name;
-  if (auto *parent =
-          clang::dyn_cast<clang::RecordDecl>(record->getDeclContext())) {
-    parent_name = parent->getIdentifier()
-                      ? parent->getIdentifier()->getName().str()
-                      : synthesizeAnonRecordName(parent);
-    parent_name += '_';
-  }
-  return std::format("{}anon_{}", parent_name, GetAnonIndex(record));
-}
-
 } // namespace
 
 PushASTContext::PushASTContext(clang::ASTContext &ctx) : prev_(ctx_) {
@@ -760,7 +748,7 @@ std::string ToString(const clang::NamedDecl *decl) {
     if (auto *typedef_decl = record->getTypedefNameForAnonDecl()) {
       return ToString(clang::cast<clang::NamedDecl>(typedef_decl));
     }
-    return synthesizeAnonRecordName(record);
+    return GetNamedDeclAsString(record);
   }
 
   if (auto *enum_decl = clang::dyn_cast<clang::EnumDecl>(decl);
diff --git a/tests/unit/local_anon_struct_collision.c b/tests/unit/local_anon_struct_collision.c
new file mode 100644
index 00000000..ee4f8b92
--- /dev/null
+++ b/tests/unit/local_anon_struct_collision.c
@@ -0,0 +1,27 @@
+#include <assert.h>
+
+int first(void) {
+  struct {
+    int x;
+    int y;
+  } p;
+  p.x = 1;
+  p.y = 2;
+  return p.x + p.y;
+}
+
+int second(void) {
+  struct {
+    long a;
+    long b;
+  } q;
+  q.a = 10;
+  q.b = 20;
+  return (int)(q.a + q.b);
+}
+
+int main(void) {
+  assert(first() == 3);
+  assert(second() == 30);
+  return 0;
+}
diff --git a/tests/unit/out/refcount/anonymous-struct.rs b/tests/unit/out/refcount/anonymous-struct.rs
index 60f64c58..fcd7db80 100644
--- a/tests/unit/out/refcount/anonymous-struct.rs
+++ b/tests/unit/out/refcount/anonymous-struct.rs
@@ -33,11 +33,11 @@ impl ByteRepr for Outer_Named {
     }
 }
 #[derive(Default)]
-pub struct Outer_anon_0 {
+pub struct anon_0 {
     pub c: Value<i32>,
     pub d: Value<i32>,
 }
-impl Clone for Outer_anon_0 {
+impl Clone for anon_0 {
     fn clone(&self) -> Self {
         let mut this = Self {
             c: Rc::new(RefCell::new((*self.c.borrow()))),
@@ -46,7 +46,7 @@ impl Clone for Outer_anon_0 {
         this
     }
 }
-impl ByteRepr for Outer_anon_0 {
+impl ByteRepr for anon_0 {
     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]);
@@ -59,11 +59,11 @@ impl ByteRepr for Outer_anon_0 {
     }
 }
 #[derive(Default)]
-pub struct Outer_anon_1 {
+pub struct anon_1 {
     pub g: Value<i32>,
     pub h: Value<i32>,
 }
-impl Clone for Outer_anon_1 {
+impl Clone for anon_1 {
     fn clone(&self) -> Self {
         let mut this = Self {
             g: Rc::new(RefCell::new((*self.g.borrow()))),
@@ -72,7 +72,7 @@ impl Clone for Outer_anon_1 {
         this
     }
 }
-impl ByteRepr for Outer_anon_1 {
+impl ByteRepr for anon_1 {
     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]);
@@ -85,11 +85,11 @@ impl ByteRepr for Outer_anon_1 {
     }
 }
 #[derive(Default)]
-pub struct Outer_anon_2 {
+pub struct anon_2 {
     pub e: Value<i32>,
     pub f: Value<i32>,
 }
-impl Clone for Outer_anon_2 {
+impl Clone for anon_2 {
     fn clone(&self) -> Self {
         let mut this = Self {
             e: Rc::new(RefCell::new((*self.e.borrow()))),
@@ -98,7 +98,7 @@ impl Clone for Outer_anon_2 {
         this
     }
 }
-impl ByteRepr for Outer_anon_2 {
+impl ByteRepr for anon_2 {
     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]);
@@ -111,10 +111,10 @@ impl ByteRepr for Outer_anon_2 {
     }
 }
 #[derive(Default)]
-pub struct Outer_anon_3_anon_0 {
+pub struct anon_4 {
     pub j: Value<i32>,
 }
-impl Clone for Outer_anon_3_anon_0 {
+impl Clone for anon_4 {
     fn clone(&self) -> Self {
         let mut this = Self {
             j: Rc::new(RefCell::new((*self.j.borrow()))),
@@ -122,7 +122,7 @@ impl Clone for Outer_anon_3_anon_0 {
         this
     }
 }
-impl ByteRepr for Outer_anon_3_anon_0 {
+impl ByteRepr for anon_4 {
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.j.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -133,10 +133,10 @@ impl ByteRepr for Outer_anon_3_anon_0 {
     }
 }
 #[derive(Default)]
-pub struct Outer_anon_3_anon_1 {
+pub struct anon_5 {
     pub k: Value<i32>,
 }
-impl Clone for Outer_anon_3_anon_1 {
+impl Clone for anon_5 {
     fn clone(&self) -> Self {
         let mut this = Self {
             k: Rc::new(RefCell::new((*self.k.borrow()))),
@@ -144,7 +144,7 @@ impl Clone for Outer_anon_3_anon_1 {
         this
     }
 }
-impl ByteRepr for Outer_anon_3_anon_1 {
+impl ByteRepr for anon_5 {
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.k.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -155,29 +155,29 @@ impl ByteRepr for Outer_anon_3_anon_1 {
     }
 }
 #[derive(Default)]
-pub struct Outer_anon_3 {
+pub struct anon_3 {
     pub i: Value<i32>,
-    pub inner_named: Value<Outer_anon_3_anon_0>,
-    pub anon_1: Value<Outer_anon_3_anon_1>,
+    pub inner_named: Value<anon_4>,
+    pub anon_5: Value<anon_5>,
 }
-impl Clone for Outer_anon_3 {
+impl Clone for anon_3 {
     fn clone(&self) -> Self {
         let mut this = Self {
             i: Rc::new(RefCell::new((*self.i.borrow()))),
             inner_named: Rc::new(RefCell::new((*self.inner_named.borrow()).clone())),
-            anon_1: Rc::new(RefCell::new((*self.anon_1.borrow()).clone())),
+            anon_5: Rc::new(RefCell::new((*self.anon_5.borrow()).clone())),
         };
         this
     }
 }
-impl ByteRepr for Outer_anon_3 {}
+impl ByteRepr for anon_3 {}
 #[derive(Default)]
 pub struct Outer {
     pub named: Value<Outer_Named>,
-    pub anonymous_named_0: Value<Outer_anon_0>,
-    pub anonymous_named_1: Value<Outer_anon_1>,
-    pub anon_2: Value<Outer_anon_2>,
-    pub anon_3: Value<Outer_anon_3>,
+    pub anonymous_named_0: Value<anon_0>,
+    pub anonymous_named_1: Value<anon_1>,
+    pub anon_2: Value<anon_2>,
+    pub anon_3: Value<anon_3>,
 }
 impl Clone for Outer {
     fn clone(&self) -> Self {
@@ -201,24 +201,24 @@ fn main_0() -> i32 {
             a: Rc::new(RefCell::new(<i32>::default())),
             b: Rc::new(RefCell::new(<i32>::default())),
         })),
-        anonymous_named_0: Rc::new(RefCell::new(Outer_anon_0 {
+        anonymous_named_0: Rc::new(RefCell::new(anon_0 {
             c: Rc::new(RefCell::new(<i32>::default())),
             d: Rc::new(RefCell::new(<i32>::default())),
         })),
-        anonymous_named_1: Rc::new(RefCell::new(Outer_anon_1 {
+        anonymous_named_1: Rc::new(RefCell::new(anon_1 {
             g: Rc::new(RefCell::new(<i32>::default())),
             h: Rc::new(RefCell::new(<i32>::default())),
         })),
-        anon_2: Rc::new(RefCell::new(Outer_anon_2 {
+        anon_2: Rc::new(RefCell::new(anon_2 {
             e: Rc::new(RefCell::new(<i32>::default())),
             f: Rc::new(RefCell::new(<i32>::default())),
         })),
-        anon_3: Rc::new(RefCell::new(Outer_anon_3 {
+        anon_3: Rc::new(RefCell::new(anon_3 {
             i: Rc::new(RefCell::new(<i32>::default())),
-            inner_named: Rc::new(RefCell::new(Outer_anon_3_anon_0 {
+            inner_named: Rc::new(RefCell::new(anon_4 {
                 j: Rc::new(RefCell::new(<i32>::default())),
             })),
-            anon_1: Rc::new(RefCell::new(Outer_anon_3_anon_1 {
+            anon_5: Rc::new(RefCell::new(anon_5 {
                 k: Rc::new(RefCell::new(<i32>::default())),
             })),
         })),
@@ -235,7 +235,7 @@ fn main_0() -> i32 {
     (*(*(*(*o.borrow()).anon_3.borrow()).inner_named.borrow())
         .j
         .borrow_mut()) = 10;
-    (*(*(*(*o.borrow()).anon_3.borrow()).anon_1.borrow())
+    (*(*(*(*o.borrow()).anon_3.borrow()).anon_5.borrow())
         .k
         .borrow_mut()) = 11;
     assert!(((*(*(*o.borrow()).named.borrow()).a.borrow()) == 1));
@@ -254,17 +254,17 @@ fn main_0() -> i32 {
             == 10)
     );
     assert!(
-        ((*(*(*(*o.borrow()).anon_3.borrow()).anon_1.borrow())
+        ((*(*(*(*o.borrow()).anon_3.borrow()).anon_5.borrow())
             .k
             .borrow())
             == 11)
     );
     #[derive(Default)]
-    pub struct anon_0 {
+    pub struct anon_6 {
         pub x: Value<i32>,
         pub z: Value<i32>,
     }
-    impl Clone for anon_0 {
+    impl Clone for anon_6 {
         fn clone(&self) -> Self {
             let mut this = Self {
                 x: Rc::new(RefCell::new((*self.x.borrow()))),
@@ -273,7 +273,7 @@ fn main_0() -> i32 {
             this
         }
     }
-    impl ByteRepr for anon_0 {
+    impl ByteRepr for anon_6 {
         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]);
@@ -285,7 +285,7 @@ fn main_0() -> i32 {
             }
         }
     };
-    let s: Value<anon_0> = Rc::new(RefCell::new(<anon_0>::default()));
+    let s: Value<anon_6> = Rc::new(RefCell::new(<anon_6>::default()));
     (*(*s.borrow()).x.borrow_mut()) = 1;
     (*(*s.borrow()).z.borrow_mut()) = 2;
     assert!(
diff --git a/tests/unit/out/refcount/anonymous-struct_c.rs b/tests/unit/out/refcount/anonymous-struct_c.rs
index d682a2d6..23ce8df8 100644
--- a/tests/unit/out/refcount/anonymous-struct_c.rs
+++ b/tests/unit/out/refcount/anonymous-struct_c.rs
@@ -24,11 +24,11 @@ impl ByteRepr for Named {
     }
 }
 #[derive(Default)]
-pub struct Outer_anon_0 {
+pub struct anon_0 {
     pub c: Value<i32>,
     pub d: Value<i32>,
 }
-impl ByteRepr for Outer_anon_0 {
+impl ByteRepr for anon_0 {
     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]);
@@ -41,11 +41,11 @@ impl ByteRepr for Outer_anon_0 {
     }
 }
 #[derive(Default)]
-pub struct Outer_anon_1 {
+pub struct anon_1 {
     pub g: Value<i32>,
     pub h: Value<i32>,
 }
-impl ByteRepr for Outer_anon_1 {
+impl ByteRepr for anon_1 {
     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]);
@@ -58,11 +58,11 @@ impl ByteRepr for Outer_anon_1 {
     }
 }
 #[derive(Default)]
-pub struct Outer_anon_2 {
+pub struct anon_2 {
     pub e: Value<i32>,
     pub f: Value<i32>,
 }
-impl ByteRepr for Outer_anon_2 {
+impl ByteRepr for anon_2 {
     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]);
@@ -75,10 +75,10 @@ impl ByteRepr for Outer_anon_2 {
     }
 }
 #[derive(Default)]
-pub struct Outer_anon_3_anon_0 {
+pub struct anon_4 {
     pub j: Value<i32>,
 }
-impl ByteRepr for Outer_anon_3_anon_0 {
+impl ByteRepr for anon_4 {
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.j.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -89,10 +89,10 @@ impl ByteRepr for Outer_anon_3_anon_0 {
     }
 }
 #[derive(Default)]
-pub struct Outer_anon_3_anon_1 {
+pub struct anon_5 {
     pub k: Value<i32>,
 }
-impl ByteRepr for Outer_anon_3_anon_1 {
+impl ByteRepr for anon_5 {
     fn to_bytes(&self, buf: &mut [u8]) {
         (*self.k.borrow()).to_bytes(&mut buf[0..4]);
     }
@@ -103,19 +103,19 @@ impl ByteRepr for Outer_anon_3_anon_1 {
     }
 }
 #[derive(Default)]
-pub struct Outer_anon_3 {
+pub struct anon_3 {
     pub i: Value<i32>,
-    pub inner_named: Value<Outer_anon_3_anon_0>,
-    pub anon_1: Value<Outer_anon_3_anon_1>,
+    pub inner_named: Value<anon_4>,
+    pub anon_5: Value<anon_5>,
 }
-impl ByteRepr for Outer_anon_3 {}
+impl ByteRepr for anon_3 {}
 #[derive(Default)]
 pub struct Outer {
     pub named: Value<Named>,
-    pub anon0: Value<Outer_anon_0>,
-    pub anon1: Value<Outer_anon_1>,
-    pub anon_2: Value<Outer_anon_2>,
-    pub anon_3: Value<Outer_anon_3>,
+    pub anon0: Value<anon_0>,
+    pub anon1: Value<anon_1>,
+    pub anon_2: Value<anon_2>,
+    pub anon_3: Value<anon_3>,
 }
 impl ByteRepr for Outer {}
 pub fn main() {
@@ -127,10 +127,10 @@ fn main_0() -> i32 {
             a: Rc::new(RefCell::new(0)),
             b: Rc::new(RefCell::new(<i32>::default())),
         })),
-        anon0: Rc::new(RefCell::new(<Outer_anon_0>::default())),
-        anon1: Rc::new(RefCell::new(<Outer_anon_1>::default())),
-        anon_2: Rc::new(RefCell::new(<Outer_anon_2>::default())),
-        anon_3: Rc::new(RefCell::new(<Outer_anon_3>::default())),
+        anon0: Rc::new(RefCell::new(<anon_0>::default())),
+        anon1: Rc::new(RefCell::new(<anon_1>::default())),
+        anon_2: Rc::new(RefCell::new(<anon_2>::default())),
+        anon_3: Rc::new(RefCell::new(<anon_3>::default())),
     }));
     (*(*(*o.borrow()).named.borrow()).a.borrow_mut()) = 1;
     (*(*(*o.borrow()).named.borrow()).b.borrow_mut()) = 2;
@@ -144,7 +144,7 @@ fn main_0() -> i32 {
     (*(*(*(*o.borrow()).anon_3.borrow()).inner_named.borrow())
         .j
         .borrow_mut()) = 10;
-    (*(*(*(*o.borrow()).anon_3.borrow()).anon_1.borrow())
+    (*(*(*(*o.borrow()).anon_3.borrow()).anon_5.borrow())
         .k
         .borrow_mut()) = 11;
     assert!(((((*(*(*o.borrow()).named.borrow()).a.borrow()) == 1) as i32) != 0));
@@ -164,18 +164,18 @@ fn main_0() -> i32 {
             != 0)
     );
     assert!(
-        ((((*(*(*(*o.borrow()).anon_3.borrow()).anon_1.borrow())
+        ((((*(*(*(*o.borrow()).anon_3.borrow()).anon_5.borrow())
             .k
             .borrow())
             == 11) as i32)
             != 0)
     );
     #[derive(Default)]
-    pub struct anon_0 {
+    pub struct anon_6 {
         pub x: Value<i32>,
         pub z: Value<i32>,
     }
-    impl ByteRepr for anon_0 {
+    impl ByteRepr for anon_6 {
         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]);
@@ -187,7 +187,7 @@ fn main_0() -> i32 {
             }
         }
     };
-    let s: Value<anon_0> = <Value<anon_0>>::default();
+    let s: Value<anon_6> = <Value<anon_6>>::default();
     (*(*s.borrow()).x.borrow_mut()) = 1;
     (*(*s.borrow()).z.borrow_mut()) = 2;
     assert!(
diff --git a/tests/unit/out/refcount/local_anon_struct_collision.rs b/tests/unit/out/refcount/local_anon_struct_collision.rs
new file mode 100644
index 00000000..c4b23e73
--- /dev/null
+++ b/tests/unit/out/refcount/local_anon_struct_collision.rs
@@ -0,0 +1,62 @@
+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};
+pub fn first_0() -> i32 {
+    #[derive(Default)]
+    pub struct anon_1 {
+        pub x: Value<i32>,
+        pub y: Value<i32>,
+    }
+    impl ByteRepr for anon_1 {
+        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]))),
+            }
+        }
+    };
+    let p: Value<anon_1> = <Value<anon_1>>::default();
+    (*(*p.borrow()).x.borrow_mut()) = 1;
+    (*(*p.borrow()).y.borrow_mut()) = 2;
+    return ((*(*p.borrow()).x.borrow()) + (*(*p.borrow()).y.borrow()));
+}
+pub fn second_2() -> i32 {
+    #[derive(Default)]
+    pub struct anon_3 {
+        pub a: Value<i64>,
+        pub b: Value<i64>,
+    }
+    impl ByteRepr for anon_3 {
+        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]);
+        }
+        fn from_bytes(buf: &[u8]) -> Self {
+            Self {
+                a: Rc::new(RefCell::new(<i64>::from_bytes(&buf[0..8]))),
+                b: Rc::new(RefCell::new(<i64>::from_bytes(&buf[8..16]))),
+            }
+        }
+    };
+    let q: Value<anon_3> = <Value<anon_3>>::default();
+    (*(*q.borrow()).a.borrow_mut()) = 10_i64;
+    (*(*q.borrow()).b.borrow_mut()) = 20_i64;
+    return (((*(*q.borrow()).a.borrow()) + (*(*q.borrow()).b.borrow())) as i32);
+}
+pub fn main() {
+    std::process::exit(main_0());
+}
+fn main_0() -> i32 {
+    assert!((((({ first_0() }) == 3) as i32) != 0));
+    assert!((((({ second_2() }) == 30) as i32) != 0));
+    return 0;
+}
diff --git a/tests/unit/out/unsafe/anonymous-struct.rs b/tests/unit/out/unsafe/anonymous-struct.rs
index 8940f0ac..59c69a7f 100644
--- a/tests/unit/out/unsafe/anonymous-struct.rs
+++ b/tests/unit/out/unsafe/anonymous-struct.rs
@@ -14,47 +14,47 @@ pub struct Outer_Named {
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Outer_anon_0 {
+pub struct anon_0 {
     pub c: i32,
     pub d: i32,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Outer_anon_1 {
+pub struct anon_1 {
     pub g: i32,
     pub h: i32,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Outer_anon_2 {
+pub struct anon_2 {
     pub e: i32,
     pub f: i32,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Outer_anon_3_anon_0 {
+pub struct anon_4 {
     pub j: i32,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Outer_anon_3_anon_1 {
+pub struct anon_5 {
     pub k: i32,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Outer_anon_3 {
+pub struct anon_3 {
     pub i: i32,
-    pub inner_named: Outer_anon_3_anon_0,
-    pub anon_1: Outer_anon_3_anon_1,
+    pub inner_named: anon_4,
+    pub anon_5: anon_5,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
 pub struct Outer {
     pub named: Outer_Named,
-    pub anonymous_named_0: Outer_anon_0,
-    pub anonymous_named_1: Outer_anon_1,
-    pub anon_2: Outer_anon_2,
-    pub anon_3: Outer_anon_3,
+    pub anonymous_named_0: anon_0,
+    pub anonymous_named_1: anon_1,
+    pub anon_2: anon_2,
+    pub anon_3: anon_3,
 }
 pub fn main() {
     unsafe {
@@ -64,13 +64,13 @@ pub fn main() {
 unsafe fn main_0() -> i32 {
     let mut o: Outer = Outer {
         named: Outer_Named { a: 0_i32, b: 0_i32 },
-        anonymous_named_0: Outer_anon_0 { c: 0_i32, d: 0_i32 },
-        anonymous_named_1: Outer_anon_1 { g: 0_i32, h: 0_i32 },
-        anon_2: Outer_anon_2 { e: 0_i32, f: 0_i32 },
-        anon_3: Outer_anon_3 {
+        anonymous_named_0: anon_0 { c: 0_i32, d: 0_i32 },
+        anonymous_named_1: anon_1 { g: 0_i32, h: 0_i32 },
+        anon_2: anon_2 { e: 0_i32, f: 0_i32 },
+        anon_3: anon_3 {
             i: 0_i32,
-            inner_named: Outer_anon_3_anon_0 { j: 0_i32 },
-            anon_1: Outer_anon_3_anon_1 { k: 0_i32 },
+            inner_named: anon_4 { j: 0_i32 },
+            anon_5: anon_5 { k: 0_i32 },
         },
     };
     o.named.a = 1;
@@ -83,7 +83,7 @@ unsafe fn main_0() -> i32 {
     o.anon_2.f = 8;
     o.anon_3.i = 9;
     o.anon_3.inner_named.j = 10;
-    o.anon_3.anon_1.k = 11;
+    o.anon_3.anon_5.k = 11;
     assert!(((o.named.a) == (1)));
     assert!(((o.named.b) == (2)));
     assert!(((o.anonymous_named_0.c) == (3)));
@@ -94,14 +94,14 @@ unsafe fn main_0() -> i32 {
     assert!(((o.anon_2.f) == (8)));
     assert!(((o.anon_3.i) == (9)));
     assert!(((o.anon_3.inner_named.j) == (10)));
-    assert!(((o.anon_3.anon_1.k) == (11)));
+    assert!(((o.anon_3.anon_5.k) == (11)));
     #[repr(C)]
     #[derive(Copy, Clone, Default)]
-    pub struct anon_0 {
+    pub struct anon_6 {
         pub x: i32,
         pub z: i32,
     };
-    let mut s: anon_0 = <anon_0>::default();
+    let mut s: anon_6 = <anon_6>::default();
     s.x = 1;
     s.z = 2;
     assert!(
diff --git a/tests/unit/out/unsafe/anonymous-struct_c.rs b/tests/unit/out/unsafe/anonymous-struct_c.rs
index bbf8be7b..1c9915d9 100644
--- a/tests/unit/out/unsafe/anonymous-struct_c.rs
+++ b/tests/unit/out/unsafe/anonymous-struct_c.rs
@@ -14,47 +14,47 @@ pub struct Named {
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Outer_anon_0 {
+pub struct anon_0 {
     pub c: i32,
     pub d: i32,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Outer_anon_1 {
+pub struct anon_1 {
     pub g: i32,
     pub h: i32,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Outer_anon_2 {
+pub struct anon_2 {
     pub e: i32,
     pub f: i32,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Outer_anon_3_anon_0 {
+pub struct anon_4 {
     pub j: i32,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Outer_anon_3_anon_1 {
+pub struct anon_5 {
     pub k: i32,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Outer_anon_3 {
+pub struct anon_3 {
     pub i: i32,
-    pub inner_named: Outer_anon_3_anon_0,
-    pub anon_1: Outer_anon_3_anon_1,
+    pub inner_named: anon_4,
+    pub anon_5: anon_5,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
 pub struct Outer {
     pub named: Named,
-    pub anon0: Outer_anon_0,
-    pub anon1: Outer_anon_1,
-    pub anon_2: Outer_anon_2,
-    pub anon_3: Outer_anon_3,
+    pub anon0: anon_0,
+    pub anon1: anon_1,
+    pub anon_2: anon_2,
+    pub anon_3: anon_3,
 }
 pub fn main() {
     unsafe {
@@ -64,10 +64,10 @@ pub fn main() {
 unsafe fn main_0() -> i32 {
     let mut o: Outer = Outer {
         named: Named { a: 0, b: 0_i32 },
-        anon0: <Outer_anon_0>::default(),
-        anon1: <Outer_anon_1>::default(),
-        anon_2: <Outer_anon_2>::default(),
-        anon_3: <Outer_anon_3>::default(),
+        anon0: <anon_0>::default(),
+        anon1: <anon_1>::default(),
+        anon_2: <anon_2>::default(),
+        anon_3: <anon_3>::default(),
     };
     o.named.a = 1;
     o.named.b = 2;
@@ -79,7 +79,7 @@ unsafe fn main_0() -> i32 {
     o.anon_2.f = 8;
     o.anon_3.i = 9;
     o.anon_3.inner_named.j = 10;
-    o.anon_3.anon_1.k = 11;
+    o.anon_3.anon_5.k = 11;
     assert!(((((o.named.a) == (1)) as i32) != 0));
     assert!(((((o.named.b) == (2)) as i32) != 0));
     assert!(((((o.anon0.c) == (3)) as i32) != 0));
@@ -90,14 +90,14 @@ unsafe fn main_0() -> i32 {
     assert!(((((o.anon_2.f) == (8)) as i32) != 0));
     assert!(((((o.anon_3.i) == (9)) as i32) != 0));
     assert!(((((o.anon_3.inner_named.j) == (10)) as i32) != 0));
-    assert!(((((o.anon_3.anon_1.k) == (11)) as i32) != 0));
+    assert!(((((o.anon_3.anon_5.k) == (11)) as i32) != 0));
     #[repr(C)]
     #[derive(Copy, Clone, Default)]
-    pub struct anon_0 {
+    pub struct anon_6 {
         pub x: i32,
         pub z: i32,
     };
-    let mut s: anon_0 = <anon_0>::default();
+    let mut s: anon_6 = <anon_6>::default();
     s.x = 1;
     s.z = 2;
     assert!(
diff --git a/tests/unit/out/unsafe/local_anon_struct_collision.rs b/tests/unit/out/unsafe/local_anon_struct_collision.rs
new file mode 100644
index 00000000..4e0a72bd
--- /dev/null
+++ b/tests/unit/out/unsafe/local_anon_struct_collision.rs
@@ -0,0 +1,42 @@
+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;
+pub unsafe fn first_0() -> i32 {
+    #[repr(C)]
+    #[derive(Copy, Clone, Default)]
+    pub struct anon_1 {
+        pub x: i32,
+        pub y: i32,
+    };
+    let mut p: anon_1 = <anon_1>::default();
+    p.x = 1;
+    p.y = 2;
+    return ((p.x) + (p.y));
+}
+pub unsafe fn second_2() -> i32 {
+    #[repr(C)]
+    #[derive(Copy, Clone, Default)]
+    pub struct anon_3 {
+        pub a: i64,
+        pub b: i64,
+    };
+    let mut q: anon_3 = <anon_3>::default();
+    q.a = 10_i64;
+    q.b = 20_i64;
+    return (((q.a) + (q.b)) as i32);
+}
+pub fn main() {
+    unsafe {
+        std::process::exit(main_0() as i32);
+    }
+}
+unsafe fn main_0() -> i32 {
+    assert!(((((unsafe { first_0() }) == (3)) as i32) != 0));
+    assert!(((((unsafe { second_2() }) == (30)) as i32) != 0));
+    return 0;
+}
diff --git a/tests/unit/out/unsafe/union_addrof_external.rs b/tests/unit/out/unsafe/union_addrof_external.rs
index 0084e009..266ced3e 100644
--- a/tests/unit/out/unsafe/union_addrof_external.rs
+++ b/tests/unit/out/unsafe/union_addrof_external.rs
@@ -26,11 +26,11 @@ impl Default for record {
 }
 #[repr(C)]
 #[derive(Copy, Clone)]
-pub union Container_anon_0 {
+pub union anon_0 {
     pub h: record,
     pub raw_: [u8; 128],
 }
-impl Default for Container_anon_0 {
+impl Default for anon_0 {
     fn default() -> Self {
         unsafe { std::mem::zeroed() }
     }
@@ -38,9 +38,9 @@ impl Default for Container_anon_0 {
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
 pub struct Container {
-    pub view: Container_anon_0,
+    pub view: anon_0,
 }
-pub unsafe fn fill_0(mut out: *mut ::libc::c_void, mut cap: u64) {
+pub unsafe fn fill_1(mut out: *mut ::libc::c_void, mut cap: u64) {
     let mut src: [u8; 16] = [
         0_u8, 0_u8, 0_u8, 0_u8, 0_u8, 0_u8, 0_u8, 0_u8, 0_u8, 0_u8, 0_u8, 0_u8, 0_u8, 0_u8, 0_u8,
         0_u8,
@@ -85,10 +85,9 @@ unsafe fn main_0() -> i32 {
         ((&mut c as *mut Container) as *mut Container as *mut ::libc::c_void)
     };
     (unsafe {
-        let _out: *mut ::libc::c_void =
-            ((&mut c.view as *mut Container_anon_0) as *mut ::libc::c_void);
-        let _cap: u64 = ::std::mem::size_of::<Container_anon_0>() as u64;
-        fill_0(_out, _cap)
+        let _out: *mut ::libc::c_void = ((&mut c.view as *mut anon_0) as *mut ::libc::c_void);
+        let _cap: u64 = ::std::mem::size_of::<anon_0>() as u64;
+        fill_1(_out, _cap)
     });
     assert!(((((c.view.h.code as i32) == (2)) as i32) != 0));
     assert!(
diff --git a/tests/unit/out/unsafe/union_cross_arm_cast.rs b/tests/unit/out/unsafe/union_cross_arm_cast.rs
index ecc6ac93..4cefe6d5 100644
--- a/tests/unit/out/unsafe/union_cross_arm_cast.rs
+++ b/tests/unit/out/unsafe/union_cross_arm_cast.rs
@@ -42,12 +42,12 @@ impl Default for shape_b {
 }
 #[repr(C)]
 #[derive(Copy, Clone)]
-pub union Container_anon_0 {
+pub union anon_0 {
     pub a: shape_a,
     pub b: shape_b,
     pub raw_: [u8; 64],
 }
-impl Default for Container_anon_0 {
+impl Default for anon_0 {
     fn default() -> Self {
         unsafe { std::mem::zeroed() }
     }
@@ -56,7 +56,7 @@ impl Default for Container_anon_0 {
 #[derive(Copy, Clone, Default)]
 pub struct Container {
     pub len: u32,
-    pub u: Container_anon_0,
+    pub u: anon_0,
 }
 pub fn main() {
     unsafe {
diff --git a/tests/unit/out/unsafe/union_field_alignment.rs b/tests/unit/out/unsafe/union_field_alignment.rs
index 9eaf35cf..f30c73da 100644
--- a/tests/unit/out/unsafe/union_field_alignment.rs
+++ b/tests/unit/out/unsafe/union_field_alignment.rs
@@ -8,11 +8,11 @@ use std::os::fd::{AsFd, FromRawFd, IntoRawFd};
 use std::rc::Rc;
 #[repr(C)]
 #[derive(Copy, Clone)]
-pub union node_anon_0 {
+pub union anon_0 {
     pub bytes: [u8; 1],
     pub aligner: *mut ::libc::c_void,
 }
-impl Default for node_anon_0 {
+impl Default for anon_0 {
     fn default() -> Self {
         unsafe { std::mem::zeroed() }
     }
@@ -21,7 +21,7 @@ impl Default for node_anon_0 {
 #[derive(Copy, Clone, Default)]
 pub struct node {
     pub next: *mut node,
-    pub x: node_anon_0,
+    pub x: anon_0,
 }
 pub fn main() {
     unsafe {
diff --git a/tests/unit/out/unsafe/union_memset_memcpy.rs b/tests/unit/out/unsafe/union_memset_memcpy.rs
index 0d90cf0b..a65d549e 100644
--- a/tests/unit/out/unsafe/union_memset_memcpy.rs
+++ b/tests/unit/out/unsafe/union_memset_memcpy.rs
@@ -40,12 +40,12 @@ impl Default for shape_b {
 }
 #[repr(C)]
 #[derive(Copy, Clone)]
-pub union Container_anon_0 {
+pub union anon_0 {
     pub a: shape_a,
     pub b: shape_b,
     pub raw_: [u8; 256],
 }
-impl Default for Container_anon_0 {
+impl Default for anon_0 {
     fn default() -> Self {
         unsafe { std::mem::zeroed() }
     }
@@ -53,7 +53,7 @@ impl Default for Container_anon_0 {
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
 pub struct Container {
-    pub view: Container_anon_0,
+    pub view: anon_0,
 }
 pub fn main() {
     unsafe {
diff --git a/tests/unit/out/unsafe/union_nested.rs b/tests/unit/out/unsafe/union_nested.rs
index ccc9f939..280df299 100644
--- a/tests/unit/out/unsafe/union_nested.rs
+++ b/tests/unit/out/unsafe/union_nested.rs
@@ -22,11 +22,11 @@ impl Default for record {
 }
 #[repr(C)]
 #[derive(Copy, Clone)]
-pub union inner_anon_0 {
+pub union anon_0 {
     pub h: record,
     pub raw_: [u8; 128],
 }
-impl Default for inner_anon_0 {
+impl Default for anon_0 {
     fn default() -> Self {
         unsafe { std::mem::zeroed() }
     }
@@ -34,15 +34,15 @@ impl Default for inner_anon_0 {
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
 pub struct inner {
-    pub view: inner_anon_0,
+    pub view: anon_0,
 }
 #[repr(C)]
 #[derive(Copy, Clone)]
-pub union Outer_anon_0 {
+pub union anon_1 {
     pub h: record,
     pub nested: inner,
 }
-impl Default for Outer_anon_0 {
+impl Default for anon_1 {
     fn default() -> Self {
         unsafe { std::mem::zeroed() }
     }
@@ -54,7 +54,7 @@ pub struct Outer {
     pub level: i32,
     pub variant: i32,
     pub len: u32,
-    pub body: Outer_anon_0,
+    pub body: anon_1,
 }
 pub fn main() {
     unsafe {
diff --git a/tests/unit/out/unsafe/union_struct_dual_use.rs b/tests/unit/out/unsafe/union_struct_dual_use.rs
index 7bbe483c..2e2beb04 100644
--- a/tests/unit/out/unsafe/union_struct_dual_use.rs
+++ b/tests/unit/out/unsafe/union_struct_dual_use.rs
@@ -17,11 +17,11 @@ pub unsafe fn sum_inner_0(mut i: *mut Inner) -> i32 {
 }
 #[repr(C)]
 #[derive(Copy, Clone)]
-pub union Outer_anon_0 {
+pub union anon_1 {
     pub inner: Inner,
     pub raw_: [u8; 16],
 }
-impl Default for Outer_anon_0 {
+impl Default for anon_1 {
     fn default() -> Self {
         unsafe { std::mem::zeroed() }
     }
@@ -29,7 +29,7 @@ impl Default for Outer_anon_0 {
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
 pub struct Outer {
-    pub u: Outer_anon_0,
+    pub u: anon_1,
 }
 pub fn main() {
     unsafe {
diff --git a/tests/unit/out/unsafe/union_tagged_many_arms.rs b/tests/unit/out/unsafe/union_tagged_many_arms.rs
index b1ac0bda..68fa5187 100644
--- a/tests/unit/out/unsafe/union_tagged_many_arms.rs
+++ b/tests/unit/out/unsafe/union_tagged_many_arms.rs
@@ -30,14 +30,14 @@ impl From<i32> for Tag {
 libcc2rs::impl_enum_inc_dec!(Tag);
 #[repr(C)]
 #[derive(Copy, Clone)]
-pub union Slot_anon_0 {
+pub union anon_0 {
     pub text: *const u8,
     pub handle: *mut ::libc::c_void,
     pub signed_n: i64,
     pub unsigned_n: u64,
     pub f: f64,
 }
-impl Default for Slot_anon_0 {
+impl Default for anon_0 {
     fn default() -> Self {
         unsafe { std::mem::zeroed() }
     }
@@ -46,7 +46,7 @@ impl Default for Slot_anon_0 {
 #[derive(Copy, Clone, Default)]
 pub struct Slot {
     pub tag: Tag,
-    pub payload: Slot_anon_0,
+    pub payload: anon_0,
 }
 pub fn main() {
     unsafe {
diff --git a/tests/unit/out/unsafe/union_tagged_simple.rs b/tests/unit/out/unsafe/union_tagged_simple.rs
index 834c22fe..b6ce9160 100644
--- a/tests/unit/out/unsafe/union_tagged_simple.rs
+++ b/tests/unit/out/unsafe/union_tagged_simple.rs
@@ -24,11 +24,11 @@ impl From<i32> for Kind {
 libcc2rs::impl_enum_inc_dec!(Kind);
 #[repr(C)]
 #[derive(Copy, Clone)]
-pub union Event_anon_0 {
+pub union anon_0 {
     pub obj: *mut ::libc::c_void,
     pub code: i32,
 }
-impl Default for Event_anon_0 {
+impl Default for anon_0 {
     fn default() -> Self {
         unsafe { std::mem::zeroed() }
     }
@@ -38,7 +38,7 @@ impl Default for Event_anon_0 {
 pub struct Event {
     pub kind: Kind,
     pub handle: *mut ::libc::c_void,
-    pub payload: Event_anon_0,
+    pub payload: anon_0,
 }
 pub fn main() {
     unsafe {
diff --git a/tests/unit/out/unsafe/union_tagged_struct_arms.rs b/tests/unit/out/unsafe/union_tagged_struct_arms.rs
index 52ec1c70..6bf0689a 100644
--- a/tests/unit/out/unsafe/union_tagged_struct_arms.rs
+++ b/tests/unit/out/unsafe/union_tagged_struct_arms.rs
@@ -26,14 +26,14 @@ impl From<i32> for Choice {
 libcc2rs::impl_enum_inc_dec!(Choice);
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Branch_anon_0_anon_0 {
+pub struct anon_1 {
     pub items: *mut *mut u8,
     pub count: i64,
     pub cursor: i64,
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Branch_anon_0_anon_1 {
+pub struct anon_2 {
     pub lo: i32,
     pub hi: i32,
     pub curr: i32,
@@ -41,7 +41,7 @@ pub struct Branch_anon_0_anon_1 {
 }
 #[repr(C)]
 #[derive(Copy, Clone, Default)]
-pub struct Branch_anon_0_anon_2 {
+pub struct anon_3 {
     pub lo: i64,
     pub hi: i64,
     pub curr: i64,
@@ -50,12 +50,12 @@ pub struct Branch_anon_0_anon_2 {
 }
 #[repr(C)]
 #[derive(Copy, Clone)]
-pub union Branch_anon_0 {
-    pub list: Branch_anon_0_anon_0,
-    pub letters: Branch_anon_0_anon_1,
-    pub integers: Branch_anon_0_anon_2,
+pub union anon_0 {
+    pub list: anon_1,
+    pub letters: anon_2,
+    pub integers: anon_3,
 }
-impl Default for Branch_anon_0 {
+impl Default for anon_0 {
     fn default() -> Self {
         unsafe { std::mem::zeroed() }
     }
@@ -65,7 +65,7 @@ impl Default for Branch_anon_0 {
 pub struct Branch {
     pub choice: Choice,
     pub index: i32,
-    pub v: Branch_anon_0,
+    pub v: anon_0,
 }
 pub fn main() {
     unsafe {
@@ -73,7 +73,7 @@ pub fn main() {
     }
 }
 unsafe fn main_0() -> i32 {
-    static mut items: [*mut u8; 3] = unsafe {
+    static mut items_4: [*mut u8; 3] = unsafe {
         [
             b"a\0".as_ptr().cast_mut(),
             b"b\0".as_ptr().cast_mut(),
@@ -83,7 +83,7 @@ unsafe fn main_0() -> i32 {
     let mut p_list: Branch = <Branch>::default();
     p_list.choice = Choice::C_LIST;
     p_list.index = 0;
-    p_list.v.list.items = items.as_mut_ptr();
+    p_list.v.list.items = items_4.as_mut_ptr();
     p_list.v.list.count = 3_i64;
     p_list.v.list.cursor = 1_i64;
     assert!(((((p_list.v.list.count) == (3_i64)) as i32) != 0));
diff --git a/tests/unit/out/unsafe/union_void_ptr_sized_deref.rs b/tests/unit/out/unsafe/union_void_ptr_sized_deref.rs
index 3391a818..b4ee56c8 100644
--- a/tests/unit/out/unsafe/union_void_ptr_sized_deref.rs
+++ b/tests/unit/out/unsafe/union_void_ptr_sized_deref.rs
@@ -26,13 +26,13 @@ impl From<i32> for Width {
 libcc2rs::impl_enum_inc_dec!(Width);
 #[repr(C)]
 #[derive(Copy, Clone)]
-pub union Sink_anon_0 {
+pub union anon_0 {
     pub text: *const u8,
     pub handle: *mut ::libc::c_void,
     pub signed_n: i64,
     pub f: f64,
 }
-impl Default for Sink_anon_0 {
+impl Default for anon_0 {
     fn default() -> Self {
         unsafe { std::mem::zeroed() }
     }
@@ -41,9 +41,9 @@ impl Default for Sink_anon_0 {
 #[derive(Copy, Clone, Default)]
 pub struct Sink {
     pub width: Width,
-    pub out: Sink_anon_0,
+    pub out: anon_0,
 }
-pub unsafe fn write_count_0(mut s: *mut Sink, mut count: i64) {
+pub unsafe fn write_count_1(mut s: *mut Sink, mut count: i64) {
     'switch: {
         let __match_cond = ((*s).width as u32);
         match __match_cond {
@@ -78,7 +78,7 @@ unsafe fn main_0() -> i32 {
     (unsafe {
         let _s: *mut Sink = (&mut s as *mut Sink);
         let _count: i64 = 1234605616436508552_i64;
-        write_count_0(_s, _count)
+        write_count_1(_s, _count)
     });
     assert!(((((buf64) == (1234605616436508552_i64)) as i32) != 0));
     s.width = Width::W_32;
@@ -86,7 +86,7 @@ unsafe fn main_0() -> i32 {
     (unsafe {
         let _s: *mut Sink = (&mut s as *mut Sink);
         let _count: i64 = 305419896_i64;
-        write_count_0(_s, _count)
+        write_count_1(_s, _count)
     });
     assert!(((((buf32) == (305419896)) as i32) != 0));
     s.width = Width::W_16;
@@ -94,7 +94,7 @@ unsafe fn main_0() -> i32 {
     (unsafe {
         let _s: *mut Sink = (&mut s as *mut Sink);
         let _count: i64 = 4660_i64;
-        write_count_0(_s, _count)
+        write_count_1(_s, _count)
     });
     assert!(((((buf16 as i32) == (4660)) as i32) != 0));
     return 0;

From ab3e31cb1adc303f00a646b3501326763f217c9c Mon Sep 17 00:00:00 2001
From: Lucian Popescu <lucian.popescu@tecnico.ulisboa.pt>
Date: Wed, 27 May 2026 11:13:42 +0100
Subject: [PATCH 2/2] Update tests

---
 tests/unit/out/unsafe/union_tagged_struct_arms.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/unit/out/unsafe/union_tagged_struct_arms.rs b/tests/unit/out/unsafe/union_tagged_struct_arms.rs
index 6bf0689a..24089174 100644
--- a/tests/unit/out/unsafe/union_tagged_struct_arms.rs
+++ b/tests/unit/out/unsafe/union_tagged_struct_arms.rs
@@ -73,7 +73,7 @@ pub fn main() {
     }
 }
 unsafe fn main_0() -> i32 {
-    static mut items_4: [*mut u8; 3] = unsafe {
+    static mut items: [*mut u8; 3] = unsafe {
         [
             b"a\0".as_ptr().cast_mut(),
             b"b\0".as_ptr().cast_mut(),
@@ -83,7 +83,7 @@ unsafe fn main_0() -> i32 {
     let mut p_list: Branch = <Branch>::default();
     p_list.choice = Choice::C_LIST;
     p_list.index = 0;
-    p_list.v.list.items = items_4.as_mut_ptr();
+    p_list.v.list.items = items.as_mut_ptr();
     p_list.v.list.count = 3_i64;
     p_list.v.list.cursor = 1_i64;
     assert!(((((p_list.v.list.count) == (3_i64)) as i32) != 0));