diff --git a/build/common.gypi b/build/common.gypi
index a2b7835d0..541e914e4 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -5,6 +5,26 @@
 {
   'variables': {
     'component%': 'static_library',
+    # angle_code is set to 1 for the core ANGLE targets defined in src/build_angle.gyp.
+    # angle_code is set to 0 for test code, sample code, and third party code.
+    # When angle_code is 1, we build with additional warning flags on Mac and Linux.
+    'angle_code%': 0,
+    'gcc_or_clang_warnings': [
+      '-Wall',
+      '-Wchar-subscripts',
+      '-Werror',
+      '-Wextra',
+      '-Wformat=2',
+      '-Winit-self',
+      '-Wno-sign-compare',
+      '-Wno-unused-function',
+      '-Wno-unused-parameter',
+      '-Wno-unknown-pragmas',
+      '-Wpacked',
+      '-Wpointer-arith',
+      '-Wundef',
+      '-Wwrite-strings',
+    ],
   },
   'target_defaults': {
     'default_configuration': 'Debug',
@@ -130,6 +150,20 @@
         },
       },
     }],
+    ['angle_code==1', {
+      'target_defaults': {
+        'conditions': [
+          ['OS=="mac"', {
+            'xcode_settings': {
+              'WARNING_CFLAGS': ['<@(gcc_or_clang_warnings)']
+            },
+          }],
+          ['OS!="win" and OS!="mac"', {
+            'cflags': ['<@(gcc_or_clang_warnings)']
+          }],
+        ]
+      }
+    }],
   ],
 }
 
diff --git a/src/build_angle.gyp b/src/build_angle.gyp
index d88a4d203..fcf4eb31d 100644
--- a/src/build_angle.gyp
+++ b/src/build_angle.gyp
@@ -3,6 +3,9 @@
 # found in the LICENSE file.
 
 {
+  'variables': {
+    'angle_code': 1,
+  },
   'target_defaults': {
     'defines': [
       'ANGLE_DISABLE_TRACE',