The only case I can think of is when the patch has lines above or below indented with spaces and a modified line with tabs. It looks OK in an editor, but the ex

The only case I can think of is when the patch has lines above or below indented with spaces and a modified line with tabs. It looks OK in an editor, but the extra +/-/space from the diff doesn't move the tabbed code, which still is indented to the tab-stop boundary (the tab "absorbs" the diff marker). The space-indented lines are moved 1 to the right by the diff marker, but the code on the tab line now looks to be 1 character too far to the left in the diff. The problem is not the tabs, instead it stems from trying to mix lines indented with tabs and lines indented with spaces.