diff --git a/lldb/include/lldb/Core/DataFileCache.h b/lldb/include/lldb/Core/DataFileCache.h
--- a/lldb/include/lldb/Core/DataFileCache.h
+++ b/lldb/include/lldb/Core/DataFileCache.h
@@ -161,7 +161,8 @@
   ///
   /// \return
   ///   True if the signature was successfully decoded, false otherwise.
-  bool Decode(const DataExtractor &data, lldb::offset_t *offset_ptr);
+  bool Decode(const lldb_private::DataExtractor &data,
+              lldb::offset_t *offset_ptr);
 };
 
 /// Many cache files require string tables to store data efficiently. This
@@ -204,7 +205,8 @@
 
   llvm::StringRef Get(uint32_t offset) const;
 
-  bool Decode(const DataExtractor &data, lldb::offset_t *offset_ptr);
+  bool Decode(const lldb_private::DataExtractor &data,
+              lldb::offset_t *offset_ptr);
 
 protected:
   /// All of the strings in the string table are contained in m_data.
diff --git a/lldb/source/Core/DataFileCache.cpp b/lldb/source/Core/DataFileCache.cpp
--- a/lldb/source/Core/DataFileCache.cpp
+++ b/lldb/source/Core/DataFileCache.cpp
@@ -219,7 +219,7 @@
   return true;
 }
 
-bool CacheSignature::Decode(const DataExtractor &data,
+bool CacheSignature::Decode(const lldb_private::DataExtractor &data,
                             lldb::offset_t *offset_ptr) {
   Clear();
   while (uint8_t sig_encoding = data.GetU8(offset_ptr)) {
@@ -284,7 +284,7 @@
   return true;
 }
 
-bool StringTableReader::Decode(const DataExtractor &data,
+bool StringTableReader::Decode(const lldb_private::DataExtractor &data,
                                lldb::offset_t *offset_ptr) {
   llvm::StringRef identifier((const char *)data.GetData(offset_ptr, 4), 4);
   if (identifier != kStringTableIdentifier)