Squashed 'import-layers/yocto-poky/' changes from dc8508f6099..67491b0c104

Yocto 2.2.2 (Morty)

Change-Id: Id9a452e28940d9f166957de243d9cb1d8818704e
git-subtree-dir: import-layers/yocto-poky
git-subtree-split: 67491b0c104101bb9f366d697edd23c895be4302
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/import-layers/yocto-poky/bitbake/lib/bb/data.py b/import-layers/yocto-poky/bitbake/lib/bb/data.py
index c1f27cd..c56965c 100644
--- a/import-layers/yocto-poky/bitbake/lib/bb/data.py
+++ b/import-layers/yocto-poky/bitbake/lib/bb/data.py
@@ -258,11 +258,13 @@
                                       not d.getVarFlag(key, 'unexport', False))
 
 def exported_vars(d):
-    for key in exported_keys(d):
+    k = list(exported_keys(d))
+    for key in k:
         try:
             value = d.getVar(key, True)
-        except Exception:
-            pass
+        except Exception as err:
+            bb.warn("%s: Unable to export ${%s}: %s" % (d.getVar("FILE", True), key, err))
+            continue
 
         if value is not None:
             yield key, str(value)