diff --git a/poky/meta/lib/oe/license.py b/poky/meta/lib/oe/license.py
index ca385d5..04f5b31 100644
--- a/poky/meta/lib/oe/license.py
+++ b/poky/meta/lib/oe/license.py
@@ -13,8 +13,8 @@
         # will exclude a trailing '+' character from LICENSE in
         # case INCOMPATIBLE_LICENSE is not a 'X+' license.
         lic = license
-        if not re.search('\+$', dwl):
-            lic = re.sub('\+', '', license)
+        if not re.search(r'\+$', dwl):
+            lic = re.sub(r'\+', '', license)
         if fnmatch(lic, dwl):
             return False
     return True
@@ -40,8 +40,8 @@
         return "invalid characters in license '%s'" % self.license
 
 license_operator_chars = '&|() '
-license_operator = re.compile('([' + license_operator_chars + '])')
-license_pattern = re.compile('[a-zA-Z0-9.+_\-]+$')
+license_operator = re.compile(r'([' + license_operator_chars + '])')
+license_pattern = re.compile(r'[a-zA-Z0-9.+_\-]+$')
 
 class LicenseVisitor(ast.NodeVisitor):
     """Get elements based on OpenEmbedded license strings"""