compile the copyright regex

diff --git a/scripts/cpp_lint.py b/scripts/cpp_lint.py
index f7898d8..e08fa4c 100755 (executable)
--- a/scripts/cpp_lint.py
+++ b/scripts/cpp_lint.py
@@ -444,6 +444,9 @@ _RE_SUPPRESSION = re.compile(r'\bNOLINT(_NEXT_LINE)?\b(\([^)]*\))?')
 # on which those errors are expected and should be suppressed.
 _error_suppressions = {}
 
+# Finds Copyright.
+_RE_COPYRIGHT = re.compile(r'Copyright')
+
 # The root directory used for deriving header guard CPP variable.
 # This is set by --root flag.
 _root = None
@@ -1370,7 +1373,7 @@ def CheckForCopyright(filename, lines, error):
   # We'll say it should occur by line 10. Don't forget there's a
   # dummy line at the front.
   for line in xrange(1, min(len(lines), 11)):
-    if re.search(r'Copyright', lines[line], re.I): break
+    if _RE_COPYRIGHT.search(lines[line], re.I): break
   else:                       # means no copyright line was found
     error(filename, 0, 'legal/copyright', 5,
           'No copyright message found.  '