FreeBSD patches to gyp, see also http://codereview.chromium.org/172032.

pylib/gyp/__init__.py

Index: pylib/gyp/__init__.py
===================================================================
--- pylib/gyp/__init__.py	(revision 601)
+++ pylib/gyp/__init__.py	(working copy)
@@ -71,6 +71,8 @@
         getattr(generator, 'generator_extra_sources_for_rules', []),
   }
 
+  print "OS =",default_variables['OS']
+
   # Process the input specific to this generator.
   result = gyp.input.Load(build_files, default_variables, includes[:],
                           depth, generator_input_info)
@@ -167,6 +169,7 @@
       options.formats = [ {'darwin':   'xcode',
                            'win32':    'msvs',
                            'cygwin':   'msvs',
+                           'freebsd6': 'make',
                            'freebsd7': 'make',
                            'freebsd8': 'make',
                            'linux2':   'scons',}[sys.platform] ]