tensorflow出现一大串 The TensorFlow library wasn't compiled to use SSE instructions, but these are ...

　　每次跑tensorflow，都会出这样的warning：

2017-12-25 20:11:49.485908: W c:\l\work\tensorflow-1.1.0\tensorflow\core\platform\cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use SSE instructions, but these are available on your machine and could speed up CPU computations.
2017-12-25 20:11:49.486234: W c:\l\work\tensorflow-1.1.0\tensorflow\core\platform\cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use SSE2 instructions, but these are available on your machine and could speed up CPU computations.
2017-12-25 20:11:49.486519: W c:\l\work\tensorflow-1.1.0\tensorflow\core\platform\cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use SSE3 instructions, but these are available on your machine and could speed up CPU computations.
2017-12-25 20:11:49.486813: W c:\l\work\tensorflow-1.1.0\tensorflow\core\platform\cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use SSE4.1 instructions, but these are available on your machine and could speed up CPU computations.
2017-12-25 20:11:49.487133: W c:\l\work\tensorflow-1.1.0\tensorflow\core\platform\cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use SSE4.2 instructions, but these are available on your machine and could speed up CPU computations.
2017-12-25 20:11:49.487414: W c:\l\work\tensorflow-1.1.0\tensorflow\core\platform\cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use AVX instructions, but these are available on your machine and could speed up CPU computations.

　　虽然不影响运行，但是看起来很累赘，就想办法把它们去掉。在代码前加上这些指令就行了：

import os
os.environ['TF_CPP_MIN_LOG_LEVEL']='2'
import tensorflow as tf

　　TF_CPP_MIN_LOG_LEVEL是tensorflow的环境变量，它的缺省值是1，显示 INFO logs 。设为2表示筛掉 WARNING

　　

　　参考：https://github.com/tensorflow/tensorflow/issues/7778