Enable per-OS @argfile limits

ChangeLog

@@ -52,4 +52,4 @@ NEW IN WAF 1.9
     instances can still define their own mappings to override the defaults, but in
     that case all mappings/precedences must be present. These features were not used in Waf 1.8.
   - Do not truncate the _task suffix from Task class names
-
+  - Task.exec_command will use @argfile when command-line limits are exceeded

waflib/Task.py

@@ -199,7 +199,7 @@ class TaskBase(evil):
 
 		# workaround for command line length limit:
 		# http://support.microsoft.com/kb/830473
-		if not isinstance(cmd, str) and len(repr(cmd)) >= 8192:
+		if not isinstance(cmd, str) and (len(repr(cmd)) >= 8192 if Utils.is_win32 else len(cmd) > 200000):
 			cmd, args = self.split_argfile(cmd)
 			try:
 				(fd, tmp) = tempfile.mkstemp()