diff --git a/render/glyph.c b/render/glyph.c
index 7fcdfd9d1..7282705d5 100644
--- a/render/glyph.c
+++ b/render/glyph.c
@@ -235,6 +235,9 @@ FindGlyphByHash (unsigned char sha1[20], int format)
     GlyphRefPtr gr;
     CARD32 signature = *(CARD32 *) sha1;
 
+    if (!globalGlyphs[format].hashSet)
+	return NULL;
+
     gr = FindGlyphRef (&globalGlyphs[format],
 		       signature, TRUE, sha1);