gtest, gmock: disable incompatible warnings.

gtest and gmock both rely heavily on exit-time destructors, and must
build with -Wno-exit-time-destructors to avoid these warnings.

gmock’s MOCK_METHODn() macros violate
-Wno-inconsistent-missing-override, so this warning is disabled for
direct dependents of gmock.

R=rsesek@chromium.org

Review URL: https://codereview.chromium.org/984393002

third_party/gmock/gmock.gyp

@@ -49,10 +49,48 @@
       'sources!': [
         'gmock/src/gmock-all.cc',
       ],
+
+      # gmock relies heavily on objects with static storage duration.
+      'xcode_settings': {
+        'WARNING_CFLAGS!': [
+          '-Wexit-time-destructors',
+        ],
+      },
+      'cflags!': [
+        '-Wexit-time-destructors',
+      ],
+
       'direct_dependent_settings': {
         'include_dirs': [
           'gmock/include',
         ],
+        'conditions': [
+          ['clang!=0', {
+            # The MOCK_METHODn() macros do not specify “override”, which
+            # triggers this warning in users: “error: 'Method' overrides a
+            # member function but is not marked 'override'
+            # [-Werror,-Winconsistent-missing-override]”. Suppress these
+            # warnings, and add -Wno-unknown-warning-option because only recent
+            # versions of clang (trunk r220703 and later, version 3.6 and
+            # later) recognize it.
+            'conditions': [
+              ['OS=="mac"', {
+                'xcode_settings': {
+                  'WARNING_CFLAGS': [
+                    '-Wno-inconsistent-missing-override',
+                    '-Wno-unknown-warning-option',
+                  ],
+                },
+              }],
+              ['OS=="linux"', {
+                'cflags': [
+                  '-Wno-inconsistent-missing-override',
+                  '-Wno-unknown-warning-option',
+                ],
+              }],
+            ],
+          }],
+        ],
       },
       'export_dependent_settings': [
         '../gtest/gtest.gyp:gtest',

third_party/gtest/gtest.gyp

@@ -53,6 +53,17 @@
       'sources!': [
         'gtest/src/gtest-all.cc',
       ],
+
+      # gtest relies heavily on objects with static storage duration.
+      'xcode_settings': {
+        'WARNING_CFLAGS!': [
+          '-Wexit-time-destructors',
+        ],
+      },
+      'cflags!': [
+        '-Wexit-time-destructors',
+      ],
+
       'direct_dependent_settings': {
         'include_dirs': [
           'gtest/include',