scripts/checkkconfigsymbols.py: support default statements

Until now, checkkonfigsymbols.py did not check default statements for
references on missing Kconfig symbols (i.e., undefined Kconfig options).
Hence, add support to parse and check the Kconfig default statement.

Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/scripts/checkkconfigsymbols.py b/scripts/checkkconfigsymbols.py
index d89371c..2f4b7ff 100755
--- a/scripts/checkkconfigsymbols.py
+++ b/scripts/checkkconfigsymbols.py
@@ -20,18 +20,20 @@
 FEATURE = r"(?:\w*[A-Z0-9]\w*){2,}"
 DEF = r"^\s*(?:menu){,1}config\s+(" + FEATURE + r")\s*"
 EXPR = r"(?:" + OPERATORS + r"|\s|" + FEATURE + r")+"
-STMT = r"^\s*(?:if|select|depends\s+on)\s+" + EXPR
+DEFAULT = r"default\s+.*?(?:if\s.+){,1}"
+STMT = r"^\s*(?:if|select|depends\s+on|(?:" + DEFAULT + r"))\s+" + EXPR
 SOURCE_FEATURE = r"(?:\W|\b)+[D]{,1}CONFIG_(" + FEATURE + r")"
 
 # regex objects
 REGEX_FILE_KCONFIG = re.compile(r".*Kconfig[\.\w+\-]*$")
-REGEX_FEATURE = re.compile(r"(" + FEATURE + r")")
+REGEX_FEATURE = re.compile(r'(?!\B"[^"]*)' + FEATURE + r'(?![^"]*"\B)')
 REGEX_SOURCE_FEATURE = re.compile(SOURCE_FEATURE)
 REGEX_KCONFIG_DEF = re.compile(DEF)
 REGEX_KCONFIG_EXPR = re.compile(EXPR)
 REGEX_KCONFIG_STMT = re.compile(STMT)
 REGEX_KCONFIG_HELP = re.compile(r"^\s+(help|---help---)\s*$")
 REGEX_FILTER_FEATURES = re.compile(r"[A-Za-z0-9]$")
+REGEX_NUMERIC = re.compile(r"0[xX][0-9a-fA-F]+|[0-9]+")
 
 
 def parse_options():
@@ -314,6 +316,9 @@
                 line = line.strip('\n')
                 features.extend(get_features_in_line(line))
             for feature in set(features):
+                if REGEX_NUMERIC.match(feature):
+                    # ignore numeric values
+                    continue
                 paths = referenced_features.get(feature, set())
                 paths.add(kfile)
                 referenced_features[feature] = paths