diff --git a/src/Diagnostic.cc b/src/Diagnostic.cc
index e0d5ec9..2167181 100644
--- a/src/Diagnostic.cc
+++ b/src/Diagnostic.cc
@@ -1,16 +1,44 @@
 #include "Diagnostic.h"
+#include "SourceLocation.h"
+#include "Tokens.h"
+
+clang::Diagnostic::Diagnostic(clang::TranslationUnit& tu, CXDiagnostic clang_diagnostic) {
+  severity=clang_getDiagnosticSeverity(clang_diagnostic);
+  severity_spelling=get_severity_spelling(severity);
+  spelling=clang_getCString(clang_getDiagnosticSpelling(clang_diagnostic));
+  clang::SourceLocation location(clang_getDiagnosticLocation(clang_diagnostic));
+  std::string tmp_path;
+  unsigned line, column, offset;
+  location.get_location_info(&tmp_path, &line, &column, &offset);
+  path=tmp_path;
+  start_location.line=line;
+  start_location.column=column;
+  start_location.offset=offset;
+  
+  clang::SourceRange range(&location, &location);
+  clang::Tokens tokens(&tu, &range);
+  if(tokens.tokens().size()==1) {
+    auto& token=tokens.tokens()[0];
+    clang::SourceRange range=token.get_source_range(&tu);
+    clang::SourceLocation location(&range, false);
+    location.get_location_info(NULL, &line, &column, &offset);
+    end_location.line=line;
+    end_location.column=column;
+    end_location.offset=offset;
+  }
+}
 
 const std::string clang::Diagnostic::get_severity_spelling(unsigned severity) {
   switch(severity) {
-    case 0:
+    case CXDiagnostic_Ignored:
       return "Ignored";
-    case 1:
+    case CXDiagnostic_Note:
       return "Note";
-    case 2:
+    case CXDiagnostic_Warning:
       return "Warning";
-    case 3:
+    case CXDiagnostic_Error:
       return "Error";
-    case 4:
+    case CXDiagnostic_Fatal:
       return "Fatal";
     default:
       return "";
diff --git a/src/Diagnostic.h b/src/Diagnostic.h
index ce4cf28..9ac3b2f 100644
--- a/src/Diagnostic.h
+++ b/src/Diagnostic.h
@@ -1,6 +1,9 @@
 #ifndef DIAGNOSTIC_H_
 #define DIAGNOSTIC_H_
 #include <string>
+#include <vector>
+#include <clang-c/Index.h>
+#include "TranslationUnit.h"
 
 namespace clang {  
   class Diagnostic {
@@ -10,6 +13,8 @@ namespace clang {
       unsigned line, column, offset;
     };
     
+    Diagnostic(clang::TranslationUnit& tu, CXDiagnostic clang_diagnostic);
+    
     static const std::string get_severity_spelling(unsigned severity);
 
     unsigned severity;
diff --git a/src/SourceRange.cc b/src/SourceRange.cc
index d6edc89..87581d4 100644
--- a/src/SourceRange.cc
+++ b/src/SourceRange.cc
@@ -10,8 +10,6 @@ SourceRange(clang::SourceLocation *start, clang::SourceLocation *end) {
   range_ = clang_getRange(start->location_, end->location_);
 }
 
-clang::SourceRange::~SourceRange() { }
-
 clang::SourceRange::SourceRange(Cursor *cursor) {
   range_ = clang_getCursorExtent(cursor->cursor_);
 }
diff --git a/src/SourceRange.h b/src/SourceRange.h
index 8cc9afe..d1f772b 100644
--- a/src/SourceRange.h
+++ b/src/SourceRange.h
@@ -7,16 +7,17 @@
 namespace clang {
   class SourceRange {
   public:
+    SourceRange() {}
     SourceRange(TranslationUnit *tu, Token *token);
     SourceRange(SourceLocation *start,
                 SourceLocation *end);
     explicit SourceRange(Cursor *cursor);
-    ~SourceRange();
 
   private:
     CXSourceRange range_;
     friend Tokens;
     friend SourceLocation;
+    friend Diagnostic;
   };
 }  // namespace clang
 #endif  // SOURCERANGE_H_
diff --git a/src/Tokens.h b/src/Tokens.h
index 344b0a0..254b74c 100644
--- a/src/Tokens.h
+++ b/src/Tokens.h
@@ -10,7 +10,7 @@ namespace clang {
     Tokens(TranslationUnit *tu, SourceRange *range);
     ~Tokens();
     std::vector<Token>& tokens();
-  protected:
+  private:
     std::vector<clang::Token> tks;
     CXToken *tokens_;
     unsigned num_tokens_;
diff --git a/src/TranslationUnit.cc b/src/TranslationUnit.cc
index 63d52e0..e9cac42 100644
--- a/src/TranslationUnit.cc
+++ b/src/TranslationUnit.cc
@@ -94,32 +94,7 @@ std::vector<clang::Diagnostic> clang::TranslationUnit::get_diagnostics() {
   std::vector<clang::Diagnostic> diagnostics;
   for(unsigned c=0;c<clang_getNumDiagnostics(tu_);c++) {
     CXDiagnostic clang_diagnostic=clang_getDiagnostic(tu_, c);
-    diagnostics.emplace_back();
-    auto& diagnostic=diagnostics.back();
-
-    diagnostic.severity=clang_getDiagnosticSeverity(clang_diagnostic);
-    diagnostic.severity_spelling=clang::Diagnostic::get_severity_spelling(diagnostic.severity);
-    diagnostic.spelling=clang_getCString(clang_getDiagnosticSpelling(clang_diagnostic));
-    SourceLocation location(clang_getDiagnosticLocation(clang_diagnostic));
-    std::string path;
-    unsigned line, column, offset;
-    location.get_location_info(&path, &line, &column, &offset);
-    diagnostic.path=path;
-    diagnostic.start_location.line=line;
-    diagnostic.start_location.column=column;
-    diagnostic.start_location.offset=offset;
-    
-    clang::SourceRange range(&location, &location);
-    clang::Tokens tokens(this, &range);
-    if(tokens.tokens().size()==1) {
-      auto& token=tokens.tokens()[0];
-      clang::SourceRange range=token.get_source_range(this);
-      clang::SourceLocation end_location(&range, false);
-      end_location.get_location_info(NULL, &line, &column, &offset);
-      diagnostic.end_location.line=line;
-      diagnostic.end_location.column=column;
-      diagnostic.end_location.offset=offset;
-    }
+    diagnostics.emplace_back(clang::Diagnostic(*this, clang_diagnostic));
   }
   return diagnostics;
 }
diff --git a/src/TranslationUnit.h b/src/TranslationUnit.h
index 9bc18fd..eb63128 100644
--- a/src/TranslationUnit.h
+++ b/src/TranslationUnit.h
@@ -15,6 +15,7 @@ namespace clang {
   class SourceRange;
   class Cursor;
   class CodeCompleteResults;
+  class Diagnostic;
 
   class TranslationUnit {
   public:
@@ -35,7 +36,7 @@ namespace clang {
                                &buffers,
                                unsigned flags=DefaultFlags());
     static unsigned DefaultFlags();
-    std::vector<Diagnostic> get_diagnostics();
+    std::vector<clang::Diagnostic> get_diagnostics();
     
   private:
     friend Token;