Update flags for nvcc.

dnnlib/tflib/custom_ops.py

@@ -69,7 +69,7 @@ def _run_cmd(cmd):
         raise RuntimeError('NVCC returned an error. See below for full command line and output log:\n\n%s\n\n%s' % (cmd, output))
 
 def _prepare_nvcc_cli(opts):
-    cmd = 'nvcc ' + opts.strip()
+    cmd = 'nvcc  --std=c++11 -DNDEBUG ' + opts.strip()
     cmd += ' --disable-warnings'
     cmd += ' --include-path "%s"' % tf.sysconfig.get_include()
     cmd += ' --include-path "%s"' % os.path.join(tf.sysconfig.get_include(), 'external', 'protobuf_archive', 'src')