Code changes to get the code to compile under GCC....

courgette/difference_estimator_unittest.cc

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "courgette/difference_estimator.h"
 
 #include <string>
 
 #include "testing/gtest/include/gtest/gtest.h"
 #include "courgette/region.h"
 
 using courgette::DifferenceEstimator;
 using courgette::Region;
 
 TEST(DifferenceEstimatorTest, TestSame) {
   static const char kString1[] = "Hello world";
   // kString2 is stack allocated to prevent string sharing.
   const char kString2[] = "Hello world";
   DifferenceEstimator difference_estimator;
   DifferenceEstimator::Base* base =
       difference_estimator.MakeBase(Region(kString1, sizeof(kString1)));
   DifferenceEstimator::Subject* subject =
       difference_estimator.MakeSubject(Region(kString2, sizeof(kString2)));
-  EXPECT_EQ(0, difference_estimator.Measure(base, subject));
+  EXPECT_EQ(0U, difference_estimator.Measure(base, subject));
 }
 
 TEST(DifferenceEstimatorTest, TestDifferent) {
   static const char kString1[] = "Hello world";
   static const char kString2[] = "Hello universe";
   DifferenceEstimator difference_estimator;
   DifferenceEstimator::Base* base =
       difference_estimator.MakeBase(Region(kString1, sizeof(kString1)));
   DifferenceEstimator::Subject* subject =
       difference_estimator.MakeSubject(Region(kString2, sizeof(kString2)));
-  EXPECT_EQ(10, difference_estimator.Measure(base, subject));
+  EXPECT_EQ(10U, difference_estimator.Measure(base, subject));
 }
 
 TEST(DifferenceEstimatorTest, TestDifferentSuperstring) {
   static const char kString1[] = "abcdabcdabcd";
   static const char kString2[] = "abcdabcdabcdabcd";
   DifferenceEstimator difference_estimator;
   DifferenceEstimator::Base* base =
       difference_estimator.MakeBase(Region(kString1, sizeof(kString1)-1));
   DifferenceEstimator::Subject* subject =
       difference_estimator.MakeSubject(Region(kString2, sizeof(kString2)-1));
-  EXPECT_EQ(1, difference_estimator.Measure(base, subject));
+  EXPECT_EQ(1U, difference_estimator.Measure(base, subject));
 }
 
 TEST(DifferenceEstimatorTest, TestDifferentSubstring) {
   static const char kString1[] = "abcdabcdabcdabcd";
   static const char kString2[] = "abcdabcdabcd";
   DifferenceEstimator difference_estimator;
   DifferenceEstimator::Base* base =
       difference_estimator.MakeBase(Region(kString1, sizeof(kString1)-1));
   DifferenceEstimator::Subject* subject =
       difference_estimator.MakeSubject(Region(kString2, sizeof(kString2)-1));
-  EXPECT_EQ(1, difference_estimator.Measure(base, subject));
+  EXPECT_EQ(1U, difference_estimator.Measure(base, subject));
 }