diff -r 052fda48962b Lib/test/regrtest.py
--- a/Lib/test/regrtest.py	Sat Sep 25 15:30:03 2010 +0200
+++ b/Lib/test/regrtest.py	Sat Sep 25 20:00:35 2010 +0200
@@ -29,6 +29,7 @@
 -d/--debug      -- print traceback for failed tests
 -q/--quiet      -- no output unless one or more tests fail
 -S/--slow       -- print the slowest 10 tests
+-g/--sysflags   -- print sys.flags values
 
 Selecting tests
 
@@ -228,7 +229,8 @@
          exclude=False, single=False, randomize=False, fromfile=None,
          findleaks=False, use_resources=None, trace=False, coverdir='coverage',
          runleaks=False, huntrleaks=False, verbose2=False, print_slow=False,
-         random_seed=None, use_mp=None, verbose3=False, forever=False):
+         random_seed=None, use_mp=None, verbose3=False, forever=False,
+         sysflags=False):
     """Execute a test suite.
 
     This also parses command-line options and modifies its behavior
@@ -256,13 +258,13 @@
 
     support.record_original_stdout(sys.stdout)
     try:
-        opts, args = getopt.getopt(sys.argv[1:], 'hvqxsSrf:lu:t:TD:NLR:FwWM:nj:',
+        opts, args = getopt.getopt(sys.argv[1:], 'hvqxsSrf:lu:t:TD:NLR:FwWM:nj:g',
             ['help', 'verbose', 'verbose2', 'verbose3', 'quiet',
              'exclude', 'single', 'slow', 'random', 'fromfile', 'findleaks',
              'use=', 'threshold=', 'trace', 'coverdir=', 'nocoverdir',
              'runleaks', 'huntrleaks=', 'memlimit=', 'randseed=',
              'multiprocess=', 'slaveargs=', 'forever', 'debug', 'start=',
-             'nowindows'])
+             'nowindows', 'sysflags'])
     except getopt.error as msg:
         usage(msg)
 
@@ -381,6 +383,8 @@
             print()   # Force a newline (just in case)
             print(json.dumps(result))
             sys.exit(0)
+        elif o in ('-g', '--sysflags'):
+            sysflags = True
         else:
             print(("No handler for option {}.  Please report this as a bug "
                    "at http://bugs.python.org.").format(o), file=sys.stderr)
@@ -478,6 +482,8 @@
         tracer = trace.Trace(ignoredirs=[sys.prefix, sys.exec_prefix,
                                          tempfile.gettempdir()],
                              trace=False, count=True)
+    if sysflags:
+        print("Testing with flags:", sys.flags)
 
     test_times = []
     support.verbose = verbose      # Tell tests to be moderately quiet