A64: Synchronize with r15545.

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index a7475b155f7c90fb0dafccb9b9d61d843cf59606..29b30c7212ee93a827c2ae9ead05450c45363aea 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -104,6 +104,10 @@
     # Interpreted regexp engine exists as platform-independent alternative
     # based where the regular expression is compiled to a bytecode.
     'v8_interpreted_regexp%': 0,
+
+    # Enable ECMAScript Internationalization API. Enabling this feature will
+    # add a dependency on the ICU library.
+    'v8_enable_i18n_support%': 0,
   },
   'target_defaults': {
     'conditions': [
@@ -125,6 +129,9 @@
       ['v8_interpreted_regexp==1', {
         'defines': ['V8_INTERPRETED_REGEXP',],
       }],
+      ['v8_enable_i18n_support==1', {
+        'defines': ['V8_I18N_SUPPORT',],
+      }],
       ['v8_target_arch=="arm"', {
         'defines': [
           'V8_TARGET_ARCH_ARM',
@@ -457,6 +464,26 @@
           }],
         ],
       }],
+      ['(OS=="linux") and (v8_target_arch=="x64")', {
+        # Check whether the host compiler and target compiler support the
+        # '-m64' option and set it if so.
+        'target_conditions': [
+          ['_toolset=="host"', {
+            'variables': {
+              'm64flag': '<!((echo | $(echo ${CXX_host:-$(which g++)}) -m64 -E - > /dev/null 2>&1) && echo "-m64" || true)',
+            },
+            'cflags': [ '<(m64flag)' ],
+            'ldflags': [ '<(m64flag)' ],
+          }],
+          ['_toolset=="target"', {
+            'variables': {
+              'm64flag': '<!((echo | $(echo ${CXX_target:-<(CXX)}) -m64 -E - > /dev/null 2>&1) && echo "-m64" || true)',
+            },
+            'cflags': [ '<(m64flag)' ],
+            'ldflags': [ '<(m64flag)' ],
+          }]
+        ],
+      }],
       ['OS=="freebsd" or OS=="openbsd"', {
         'cflags': [ '-I/usr/local/include' ],
       }],