Enable 64-bit architectures by default for Xcode 5.1 and higher

pylib/gyp/xcode_emulation.py

Index: pylib/gyp/xcode_emulation.py
diff --git a/pylib/gyp/xcode_emulation.py b/pylib/gyp/xcode_emulation.py
index d86413ac5d7825dd2cbb713239747a70fa5a9278..e1add1ff1376a3da1d97560fd06fd22b64c31e90 100644
--- a/pylib/gyp/xcode_emulation.py
+++ b/pylib/gyp/xcode_emulation.py
@@ -1449,7 +1449,7 @@ def _IOSDefaultArchForSDKRoot(sdkroot):
       return {'$(ARCHS_STANDARD)': ['armv7']}
     else:
       return {'$(ARCHS_STANDARD)': ['i386']}
-  else:
+  elif xcode_version < '0510':
     if _IOSIsDeviceSDKROOT(sdkroot):
       return {
           '$(ARCHS_STANDARD)': ['armv7', 'armv7s'],
@@ -1460,6 +1460,17 @@ def _IOSDefaultArchForSDKRoot(sdkroot):
           '$(ARCHS_STANDARD)': ['i386'],
           '$(ARCHS_STANDARD_INCLUDING_64_BIT)': ['i386', 'x86_64'],
       }
+  else:
+    if _IOSIsDeviceSDKROOT(sdkroot):
+      return {
+          '$(ARCHS_STANDARD)': ['armv7', 'armv7s', 'arm64'],
+          '$(ARCHS_STANDARD_INCLUDING_64_BIT)': ['armv7', 'armv7s', 'arm64'],
+      }
+    else:
+      return {
+          '$(ARCHS_STANDARD)': ['i386', 'x86_64'],
+          '$(ARCHS_STANDARD_INCLUDING_64_BIT)': ['i386', 'x86_64'],
+      }
 
 
 def _FilterIOSArchitectureForSDKROOT(xcode_settings):