> #0  0x00000000005e25ec in marker_position (marker=XIL(0x376b469)) at marker.c:641
 > #1  0x00000000005ced7e in mouse_face_overlay_overlaps (overlay=XIL(0x376b4e1)) at buffer.c:3058
 > #2  0x00000000004a943f in note_mouse_highlight (f=0x1603c80 <bss_sbrk_buffer+8226176>, x=170, y=120) at xdisp.c:31349

Can you please try the attached patch.  I have no idea whether this is
the correct interpretation of the semantics of 'mouse-highlight'.

Thanks, martin