diff --git a/cpp2rust/converter/converter.cpp b/cpp2rust/converter/converter.cpp
index 59943ad2..e5a85037 100644
--- a/cpp2rust/converter/converter.cpp
+++ b/cpp2rust/converter/converter.cpp
@@ -2058,6 +2058,9 @@ bool Converter::VisitUnaryOperator(clang::UnaryOperator *expr) {
     return false;
   }
   switch (opcode) {
+  case clang::UO_Extension:
+    Convert(sub_expr);
+    break;
   case clang::UO_AddrOf: {
     PushParen paren(*this);
     ConvertAddrOf(sub_expr, expr->getType());
@@ -2091,6 +2094,27 @@ bool Converter::VisitUnaryOperator(clang::UnaryOperator *expr) {
   return false;
 }
 
+bool Converter::VisitStmtExpr(clang::StmtExpr *expr) {
+  auto *body = expr->getSubStmt();
+  PushBrace brace(*this);
+  auto stmts = body->body();
+  size_t n = static_cast<size_t>(stmts.end() - stmts.begin());
+  size_t i = 0;
+  for (auto *s : stmts) {
+    ++i;
+    if (i == n) {
+      if (auto *tail = clang::dyn_cast<clang::Expr>(s)) {
+        EmitStmtExprTail(tail);
+        continue;
+      }
+    }
+    Convert(s);
+  }
+  return false;
+}
+
+void Converter::EmitStmtExprTail(clang::Expr *tail) { Convert(tail); }
+
 bool Converter::VisitConditionalOperator(clang::ConditionalOperator *expr) {
   StrCat(keyword::kIf);
   Convert(expr->getCond());
diff --git a/cpp2rust/converter/converter.h b/cpp2rust/converter/converter.h
index 8e2fda4c..b652afd6 100644
--- a/cpp2rust/converter/converter.h
+++ b/cpp2rust/converter/converter.h
@@ -248,6 +248,10 @@ class Converter : public clang::RecursiveASTVisitor<Converter> {
 
   virtual bool VisitUnaryOperator(clang::UnaryOperator *expr);
 
+  virtual bool VisitStmtExpr(clang::StmtExpr *expr);
+
+  virtual void EmitStmtExprTail(clang::Expr *tail);
+
   virtual bool VisitConditionalOperator(clang::ConditionalOperator *expr);
 
   virtual bool VisitDeclRefExpr(clang::DeclRefExpr *expr);
diff --git a/cpp2rust/converter/models/converter_refcount.cpp b/cpp2rust/converter/models/converter_refcount.cpp
index eedb1606..f47f9aa0 100644
--- a/cpp2rust/converter/models/converter_refcount.cpp
+++ b/cpp2rust/converter/models/converter_refcount.cpp
@@ -1141,6 +1141,18 @@ bool ConverterRefCount::VisitExplicitCastExpr(clang::ExplicitCastExpr *expr) {
   }
 }
 
+bool ConverterRefCount::VisitStmtExpr(clang::StmtExpr *expr) {
+  PushConversionKind push(*this, ConversionKind::FullRefCount);
+  return Converter::VisitStmtExpr(expr);
+}
+
+void ConverterRefCount::EmitStmtExprTail(clang::Expr *tail) {
+  StrCat("let __result = ");
+  Convert(tail);
+  StrCat(token::kSemiColon);
+  StrCat("__result");
+}
+
 bool ConverterRefCount::VisitBinaryOperator(clang::BinaryOperator *expr) {
   auto *lhs = expr->getLHS();
   auto *rhs = expr->getRHS();
@@ -1654,12 +1666,10 @@ void ConverterRefCount::ConvertVarInit(clang::QualType qual_type,
   }
 
   bool is_ref = qual_type->isReferenceType();
-  in_function_formals_ = true;
   PushConversionKind push(*this, ConversionKind::Unboxed, is_ref);
   StrCat(BoxValue((is_ref || qual_type->isFunctionPointerType())
                       ? ConvertFreshPointer(expr)
                       : ConvertFreshRValue(expr)));
-  in_function_formals_ = false;
 }
 
 static std::unordered_set<const clang::ValueDecl *>
diff --git a/cpp2rust/converter/models/converter_refcount.h b/cpp2rust/converter/models/converter_refcount.h
index 0ea89e68..890583e9 100644
--- a/cpp2rust/converter/models/converter_refcount.h
+++ b/cpp2rust/converter/models/converter_refcount.h
@@ -84,6 +84,10 @@ class ConverterRefCount final : public Converter {
 
   bool VisitBinaryOperator(clang::BinaryOperator *expr) override;
 
+  bool VisitStmtExpr(clang::StmtExpr *expr) override;
+
+  void EmitStmtExprTail(clang::Expr *tail) override;
+
   bool VisitInitListExpr(clang::InitListExpr *expr) override;
 
   bool VisitArraySubscriptExpr(clang::ArraySubscriptExpr *expr) override;
diff --git a/tests/unit/out/refcount/stmt_expr.rs b/tests/unit/out/refcount/stmt_expr.rs
new file mode 100644
index 00000000..c7a3bda5
--- /dev/null
+++ b/tests/unit/out/refcount/stmt_expr.rs
@@ -0,0 +1,50 @@
+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 main() {
+    std::process::exit(main_0());
+}
+fn main_0() -> i32 {
+    let x: Value<i32> = Rc::new(RefCell::new({
+        let a: Value<i32> = Rc::new(RefCell::new(1));
+        let b: Value<i32> = Rc::new(RefCell::new(2));
+        let __result = ((*a.borrow()) + (*b.borrow()));
+        __result
+    }));
+    assert!(((*x.borrow()) == 3));
+    let counter: Value<i32> = Rc::new(RefCell::new(0));
+    let y: Value<i32> = Rc::new(RefCell::new({
+        (*counter.borrow_mut()).postfix_inc();
+        let __result = ((*counter.borrow()) * 10);
+        __result
+    }));
+    assert!(((*y.borrow()) == 10));
+    assert!(((*counter.borrow()) == 1));
+    let z: Value<i32> = Rc::new(RefCell::new({
+        let v: Value<i32> = Rc::new(RefCell::new(5));
+        if ((*v.borrow()) > 0) {
+            let __rhs = ((*v.borrow()) * 2);
+            (*v.borrow_mut()) = __rhs;
+        }
+        let __result = (*v.borrow());
+        __result
+    }));
+    assert!(((*z.borrow()) == 10));
+    assert!(
+        ({
+            let inner: Value<i32> = Rc::new(RefCell::new({
+                let a: Value<i32> = Rc::new(RefCell::new(100));
+                let __result = (*a.borrow());
+                __result
+            }));
+            let __result = (*inner.borrow());
+            __result
+        } == 100)
+    );
+    return 0;
+}
diff --git a/tests/unit/out/unsafe/stmt_expr.rs b/tests/unit/out/unsafe/stmt_expr.rs
new file mode 100644
index 00000000..9a205d88
--- /dev/null
+++ b/tests/unit/out/unsafe/stmt_expr.rs
@@ -0,0 +1,46 @@
+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 fn main() {
+    unsafe {
+        std::process::exit(main_0() as i32);
+    }
+}
+unsafe fn main_0() -> i32 {
+    let mut x: i32 = {
+        let mut a: i32 = 1;
+        let mut b: i32 = 2;
+        ((a) + (b))
+    };
+    assert!(((x) == (3)));
+    let mut counter: i32 = 0;
+    let mut y: i32 = {
+        counter.postfix_inc();
+        ((counter) * (10))
+    };
+    assert!(((y) == (10)));
+    assert!(((counter) == (1)));
+    let mut z: i32 = {
+        let mut v: i32 = 5;
+        if ((v) > (0)) {
+            v = ((v) * (2));
+        }
+        v
+    };
+    assert!(((z) == (10)));
+    assert!(
+        (({
+            let mut inner: i32 = {
+                let mut a: i32 = 100;
+                a
+            };
+            inner
+        }) == (100))
+    );
+    return 0;
+}
diff --git a/tests/unit/stmt_expr.cpp b/tests/unit/stmt_expr.cpp
new file mode 100644
index 00000000..bae4c3d0
--- /dev/null
+++ b/tests/unit/stmt_expr.cpp
@@ -0,0 +1,36 @@
+#include <cassert>
+
+int main() {
+  int x = __extension__({
+    int a = 1;
+    int b = 2;
+    a + b;
+  });
+  assert(x == 3);
+
+  int counter = 0;
+  int y = ({
+    counter++;
+    counter * 10;
+  });
+  assert(y == 10);
+  assert(counter == 1);
+
+  int z = ({
+    int v = 5;
+    if (v > 0) {
+      v = v * 2;
+    }
+    v;
+  });
+  assert(z == 10);
+
+  assert(({
+           int inner = ({
+             int a = 100;
+             a;
+           });
+           inner;
+         }) == 100);
+  return 0;
+}