1 files changed, 6 insertions, 1 deletions

diff --git a/src/xterm.c b/src/xterm.c
index 9e1cabe8c3c..3539d8123af 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -4221,7 +4221,12 @@ x_draw_glyph_string (s)
 
           if (!XGetFontProperty (s->font, XA_UNDERLINE_THICKNESS, &h))
             h = 1;
-          if (!XGetFontProperty (s->font, XA_UNDERLINE_POSITION, &dy))
+          if (!XGetFontProperty (s->font, XA_UNDERLINE_POSITION, &dy)
+              /* If the font specifies a negative underline position,
+                 we'll get a huge positive number, because dy is
+                 unsigned.  This comparison is a workaround that just
+                 ignores the font's underline position in that case.  XXX */
+              || dy > s->height)
             dy = s->height - h;
       
           if (s->face->underline_defaulted_p)