Bug report

Bug summary

Code for reproduction

# 
plt.savefig('Photo.png', dpi=600, bbox_inches='tight')
#

Actual outcome

# If applicable, paste the console output here
# The output figure can be seen as below:

#

Expected outcome

Matplotlib version

• Operating system: windows10 x64
• Matplotlib version: 3.0.0
• Matplotlib backend (print(matplotlib.get_backend())):
• Python version: 3.5、3.6
• Jupyter version (if applicable):
• Other libraries:

The output figure file is strange: there is a lot of blank area on the output figure.