Subzero: Change szbuild.py to prefer Subzero by default.

pydir/szbuild.py

 #!/usr/bin/env python2
 
 import argparse
 import os
 import pipes
 import re
 import sys
 
 from utils import shellcmd
 from utils import FindBaseNaCl
@@ skipping 201 matching lines @@
             'nm {obj} | sed -n "s/.* [a-zA-Z] //p" > {sym}'
             ).format(obj=obj_sz, sym=sym_sz), echo=args.verbose)
 
     with open(sym_sz_unescaped) as f:
         sz_syms = f.read().splitlines()
     re_include_str = BuildRegex(args.include, sz_syms)
     re_exclude_str = BuildRegex(args.exclude, sz_syms)
     re_include = re.compile(re_include_str)
     re_exclude = re.compile(re_exclude_str)
     # If a symbol doesn't explicitly match re_include or re_exclude,
-    # the default MatchSymbol() result is False, unless some --exclude
-    # args are provided and no --include args are provided.
-    default_match = len(args.exclude) and not len(args.include)
+    # the default MatchSymbol() result is True, unless some --include
+    # args are provided.
+    default_match = not len(args.include)
 
     whitelist_has_items = False
     with open(whitelist_sz_unescaped, 'w') as f:
         for sym in sz_syms:
             if MatchSymbol(sym, re_include, re_exclude, default_match):
                 f.write(sym + '\n')
                 whitelist_has_items = True
     shellcmd((
         'objcopy --weaken {obj} {weak}'
         ).format(obj=obj_sz, weak=obj_sz_weak), echo=args.verbose)
@@ skipping 30 matching lines @@
     # Put the extra verbose printing at the end.
     if args.verbose:
         print 'PATH={path}'.format(path=os.environ['PATH'])
         print 'include={regex}'.format(regex=re_include_str)
         print 'exclude={regex}'.format(regex=re_exclude_str)
         print 'default_match={dm}'.format(dm=default_match)
         print 'Number of Subzero syms = {num}'.format(num=len(sz_syms))
 
 if __name__ == '__main__':
     main()