diff --git a/bitbake/lib/bb/build.py b/bitbake/lib/bb/build.py
index fab2f62a5f..aabc1b6e1d 100644
--- a/bitbake/lib/bb/build.py
+++ b/bitbake/lib/bb/build.py
@@ -149,8 +149,7 @@ def exec_func(func, d, dirs = None):
         adir = dirs[-1]
     else:
         adir = data.getVar('B', d, 1)
-        if not os.path.exists(adir):
-            adir = None
+        bb.utils.mkdirhier(adir)
 
     ispython = flags.get('python')
     if flags.get('fakeroot') and not flags.get('task'):