this isn't true for images with `:ascent 100'.
else if (it->what == IT_STRETCH)
x_produce_stretch_glyph (it);
- /* Accumulate dimensions. */
- xassert (it->ascent >= 0 && it->descent > 0);
+ /* Accumulate dimensions. Note: can't assume that it->descent > 0
+ because this isn't true for images with `:ascent 100'. */
+ xassert (it->ascent >= 0 && it->descent >= 0);
if (it->area == TEXT_AREA)
it->current_x += it->pixel_width;