gvim flashing cursor at bottom of the window

Question

I have experienced a similar problem as this question, except the cursor flashes at the bottom of the window when I move it, and I don't use vim-airline. (I made a video to illustrate what I mean.)

I tried to debug as suggested here. Starting with a pure gvim (gvim -u NONE -U NONE -N -i NONE somefile.hpp), I needed only a few tries to notice that this happens when I :set number relativenumber and :syntax on (and only with gvim). Is this a known bug? Is there someway to fix it? I tried to google it, but the only result I got was the mentioned question.

I'm running gvim 7.4 (installed via pacman) on Manjaro. (And, since I don't have reputation here, I cannot add a comment in the mentioned question, hence this new one.)