+ if t.extension not in backport_ext_candidates:
+ backport_ext_candidates.append(t.extension)
+
+if backport_ext:
+ if backport_ext=="none":
+ backport_ext = None
+ else:
+ backport_ext = extensions[backport_ext]
+
+ if backport_ext not in backport_ext_candidates:
+ print "Warning: explicitly specified backport extension %s does not look like a backport extension"
+elif backport_ext_candidates:
+ if len(backport_ext_candidates)>1:
+ print "Warning: multiple backport extension candidates: %s"%(" ".join(e.name for e in backport_ext_candidates))
+
+ for e in backport_ext_candidates:
+ if e.base_name==target_ext.base_name:
+ backport_ext = e
+
+ if not backport_ext and len(backport_ext_candidates)==1:
+ print "Warning: potential backport extension has mismatched name: %s"%backport_ext_candidates[0].name