Fix translation of type of anon enum

Author: lucic71

cpp2rust/converter/mapper.cpp

@@ -724,6 +724,11 @@ std::string ToString(clang::QualType qual_type) {
     }
   }
 
+  if (auto *tag = qual_type->getAsTagDecl();
+      tag && !tag->getIdentifier() && !tag->getTypedefNameForAnonDecl()) {
+    return ToString(clang::cast<clang::NamedDecl>(tag));
+  }
+
   std::string type;
   llvm::raw_string_ostream os(type);
   normalizeQualType(qual_type).print(os, getPrintPolicy());
@@ -738,7 +743,7 @@ std::string ToString(const clang::NamedDecl *decl) {
 
   if (auto *enum_decl = clang::dyn_cast<clang::EnumDecl>(decl);
       enum_decl && !enum_decl->getIdentifier() &&
-      enum_decl->getTypedefNameForAnonDecl() == nullptr) {
+      !enum_decl->getTypedefNameForAnonDecl()) {
     return std::format("anon_enum_{}", GetLineNumber(enum_decl));
   }