gtest shouldn't link in gtest_main.cc, as that provides its own main().

testing/gtest.gyp

Index: testing/gtest.gyp
diff --git a/testing/gtest.gyp b/testing/gtest.gyp
index 078ca3cf78eb5ad6b44cf60ee57144e86f7cc926..c7d5c6258540e4c93a6a0bc4e72498140e49526f 100644
--- a/testing/gtest.gyp
+++ b/testing/gtest.gyp
@@ -40,7 +40,6 @@
         'gtest/src/gtest-internal-inl.h',
         'gtest/src/gtest-port.cc',
         'gtest/src/gtest.cc',
-        'gtest/src/gtest_main.cc',
         'multiprocess_func_list.cc',
         'multiprocess_func_list.h',
         'platform_test.h',
@@ -65,5 +64,17 @@
         ],
       },
     },
+    {
+      # Note that calling this "gtest_main" confuses the scons build,
+      # which uses "_main" on scons files to produce special behavior.
+      'target_name': 'gtestmain',
+      'type': '<(library)',
+      'dependencies': [
+        'gtest',
+      ],
+      'sources': [
+        'gtest/src/gtest_main.cc',
+      ],
+    },
   ],
 }