Plot: legend with spurious entries

When I run the following plotting code:

data = randn(100,1);
plot(data)
hold on;
plot(zeros(100),':','Color',[0.5 0.5 0.5]);
hold off;
legend('Testdata')
legend('Location','north')

I get the following strange result:

Looks like a bug to me. When I delete the last line of code (replacement of the legend), it works well. Do I miss something?

[KSSV]

Me too got same result. This works:

data = randn(100,1);
plot(data)
hold on;
plot(zeros(100),':','Color',[0.5 0.5 0.5]);
hold off;
legend('Testdata','Location','north')

Answer 1

[Jan]

I can confirm this behavior with Matlab R2009a: Changing the location afterwards does not work.

[KSSV]

Same behavior with 2015a..