Translate default of void as unit type

Author: lucic71

cpp2rust/converter/converter.cpp

@@ -3998,6 +3998,10 @@ std::string Converter::GetArrayDefaultAsString(clang::QualType qual_type) {
 }
 
 std::string Converter::GetDefaultAsString(clang::QualType qual_type) {
+  if (qual_type->isVoidType()) {
+    return "()";
+  }
+
   if (IsVaListType(qual_type)) {
     computed_expr_type_ = ComputedExprType::FreshValue;
     return "VaList::default()";

tests/unit/out/unsafe/forward_pack.rs

@@ -64,7 +64,7 @@ pub unsafe fn chosen_overload_3(_a0: *mut i32) -> Overload {
 }
 pub unsafe fn forward_pack_4() -> i32 {
     let mut digits: i32 = 0;
-    <::libc::c_void>::default();
+    ();
     return digits;
 }
 pub unsafe fn forward_pack_5(args: *mut Tracked) -> i32 {