diff --git a/Lib/sre_compile.py b/Lib/sre_compile.py
index e5adb7e..bb17649 100644
--- a/Lib/sre_compile.py
+++ b/Lib/sre_compile.py
@@ -399,7 +399,7 @@
                 table[i+1] = table[table[i+1]-1]+1
         code.extend(table[1:]) # don't store first entry
     elif charset:
-        _compile_charset(charset, 0, code)
+        _compile_charset(charset, flags, code)
     code[skip] = len(code) - skip
 
 STRING_TYPES = [type("")]
diff --git a/Lib/test/re_tests.py b/Lib/test/re_tests.py
index 12ad201..7b237ac 100755
--- a/Lib/test/re_tests.py
+++ b/Lib/test/re_tests.py
@@ -666,4 +666,5 @@
     # bug 410271: \b broken under locales
     (r'\b.\b', 'a', SUCCEED, 'found', 'a'),
     (r'(?u)\b.\b', u, SUCCEED, 'found', u),
+    (r'(?u)\w', u, SUCCEED, 'found', u),
     ])