data_smart: Improve the calculation of config hash

For config hash, we put the keys in structure of "set()", which is not
order sensitive. Therefore when calculating the md5 value for config
hash, we need to identify the order of the keys.

(Bitbake rev: 0f1b142a3f6b8125bf023c2e5ec269618869abf7)

Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/data_smart.py

@@ -462,13 +462,14 @@ class DataSmart(MutableMapping):
         self.delVar(var)
 
     def get_hash(self):
-        data = ""
+        data = {}
         config_whitelist = set((self.getVar("BB_HASHCONFIG_WHITELIST", True) or "").split())
         keys = set(key for key in iter(self) if not key.startswith("__"))
         for key in keys:
             if key in config_whitelist:
                 continue
             value = self.getVar(key, False) or ""
-            data = data + key + ': ' + str(value) + '\n'
+            data.update({key:value})
 
-        return hashlib.md5(data).hexdigest()
+        data_str = str([(k, data[k]) for k in sorted(data.keys())])
+        return hashlib.md5(data_str).hexdigest()