Bug 580987 – SIGFPE in pango_glyph_string_index_to_x

Be pedantic about broken cluster setup, avoid div-by-zero.

1 files changed, 6 insertions, 0 deletions

diff --git a/pango/glyphstring.c b/pango/glyphstring.c
index 8fb70313..2e3a9f80 100644
--- a/pango/glyphstring.c
+++ b/pango/glyphstring.c
@@ -506,6 +506,12 @@ pango_glyph_string_index_to_x (PangoGlyphString *glyphs,
   if (trailing)
     cluster_offset += 1;
 
+  if (G_UNLIKELY (!cluster_chars)) /* pedantic */
+    {
+      *x_pos = start_xpos;
+      return;
+    }
+
   *x_pos = ((cluster_chars - cluster_offset) * start_xpos +
 	    cluster_offset * end_xpos) / cluster_chars;
 }