diff --git a/cpp/CMakeLists.txt b/cpp/CMakeLists.txt
index 71fbb256..4d9265af 100644
--- a/cpp/CMakeLists.txt
+++ b/cpp/CMakeLists.txt
@@ -86,8 +86,7 @@ endif()
 
 if( CMAKE_COMPILER_IS_GNUCXX OR COMPILER_IS_CLANG )
   # We want all warnings, and warnings should be treated as errors
-	# TODO: -Wextra?
-  add_definitions( -Wall -Werror )
+  add_definitions( -Wall -Wextra -Werror )
 endif()
 
 add_subdirectory( tests )
diff --git a/cpp/Candidate.cpp b/cpp/Candidate.cpp
index 120054a6..28d778a4 100644
--- a/cpp/Candidate.cpp
+++ b/cpp/Candidate.cpp
@@ -33,7 +33,7 @@ std::string GetWordBoundaryChars( const std::string &text )
 {
   std::string result;
 
-  for ( int i = 0; i < text.size(); ++i )
+  for ( uint i = 0; i < text.size(); ++i )
   {
     if ( i == 0 ||
          IsUppercase( text[ i ] ) ||
diff --git a/cpp/LetterHash.cpp b/cpp/LetterHash.cpp
index ace88714..7895d0ec 100644
--- a/cpp/LetterHash.cpp
+++ b/cpp/LetterHash.cpp
@@ -16,6 +16,7 @@
 // along with YouCompleteMe.  If not, see <http://www.gnu.org/licenses/>.
 
 #include "LetterHash.h"
+#include "standard.h"
 
 namespace YouCompleteMe
 {
@@ -45,7 +46,7 @@ LetterHash::LetterHash()
 {
 	letters_.resize( kNumLetters );
 
-	for ( int i = 0; i < letters_.size(); ++i )
+	for ( uint i = 0; i < letters_.size(); ++i )
 	{
 		letters_[ i ] = NULL;
 	}
@@ -54,7 +55,7 @@ LetterHash::LetterHash()
 
 LetterHash::~LetterHash()
 {
-	for ( int i = 0; i < letters_.size(); ++i )
+	for ( uint i = 0; i < letters_.size(); ++i )
 	{
 	  delete letters_[ i ];
 	}
diff --git a/cpp/LetterNode.cpp b/cpp/LetterNode.cpp
index 05639d5a..3a2ba6ed 100644
--- a/cpp/LetterNode.cpp
+++ b/cpp/LetterNode.cpp
@@ -15,8 +15,8 @@
 // You should have received a copy of the GNU General Public License
 // along with YouCompleteMe.  If not, see <http://www.gnu.org/licenses/>.
 
-#include "standard.h"
 #include "LetterNode.h"
+#include "standard.h"
 
 
 namespace YouCompleteMe
@@ -36,7 +36,7 @@ LetterNode::LetterNode( const std::string &text )
 
   letternode_per_text_index_.resize( text.size() );
 
-  for (int i = 0; i < text.size(); ++i)
+  for ( uint i = 0; i < text.size(); ++i)
   {
     char letter = text[ i ];
     LetterNode *node = new LetterNode( letter );
@@ -44,7 +44,8 @@ LetterNode::LetterNode( const std::string &text )
     letternode_per_text_index_[ i ] = boost::shared_ptr< LetterNode >( node );
   }
 
-  for ( int i = letternode_per_text_index_.size() - 1; i >= 0; --i )
+  for ( int i = static_cast< int >( letternode_per_text_index_.size() ) - 1;
+        i >= 0; --i )
   {
     LetterNode *node_to_add = letternode_per_text_index_[ i ].get();
 
diff --git a/cpp/Result.cpp b/cpp/Result.cpp
index 84ad4946..1203cc20 100644
--- a/cpp/Result.cpp
+++ b/cpp/Result.cpp
@@ -16,6 +16,7 @@
 // along with YouCompleteMe.  If not, see <http://www.gnu.org/licenses/>.
 
 #include "Result.h"
+#include "standard.h"
 #include "Utils.h"
 #include <boost/algorithm/string.hpp>
 
@@ -30,8 +31,8 @@ namespace
 int NumWordBoundaryCharMatches( const std::string &query,
                                 const std::string &word_boundary_chars )
 {
-  int i = 0;
-  int j = 0;
+  uint i = 0;
+  uint j = 0;
   while ( j < query.size() && i < word_boundary_chars.size() )
   {
     if ( toupper( query[ j ] ) == toupper( word_boundary_chars[ i ] ) )
diff --git a/cpp/standard.h b/cpp/standard.h
index 03555af5..6948332c 100644
--- a/cpp/standard.h
+++ b/cpp/standard.h
@@ -20,3 +20,11 @@
 // We're most definitely not going to use
 // it as BOOST_FOREACH.
 #define foreach BOOST_FOREACH
+
+
+namespace YouCompleteMe
+{
+
+typedef unsigned int uint;
+
+} // namespace YouCompleteMe