ax.fill broken for log scale and values below zero

When using ax.fill_between in log scale plots with y-values below zero, the result looks broken and areas are filled that should not be filled

Code for reproduction

importnumpyasnpimportmatplotlib.pyplotaspltxdata=np.arange(0,10,0.01)ydata=np.exp(-xdata)edata=0.2*(10-xdata)*np.cos(5*xdata)*np.exp(-xdata)fig,ax=plt.subplots()plt.yscale('log')ax.fill_between(xdata,ydata-edata,ydata+edata)plt.savefig("test.png")

Actual outcome

Expected outcome

The correct example has been generated with matplotlib-2.0.2-1

Probably related:#8623
How to deal with invalid values in log scale plots is certainly a matter of definition. However, it should never happen that areas are filled that should not be filled, as it is the case in the example above.

Matplotlib version

• Operating system: arch linux
• Matplotlib version: 2.1.0-1
• Matplotlib backend: Qt5Agg
• Python version: 3.6.2
• Other libraries: numpy version: 1.13.3-1

Everything installed using the package manager of arch linux.