diff --git a/render/glyph.c b/render/glyph.c
index f624be97b..90c387731 100644
--- a/render/glyph.c
+++ b/render/glyph.c
@@ -382,7 +382,8 @@ AllocateGlyph(xGlyphInfo * gi, int fdepth)
 static Bool
 AllocateGlyphHash(GlyphHashPtr hash, GlyphHashSetPtr hashSet)
 {
-    assert(hashSet);
+    if (hashSet == NULL)
+        return FALSE;
     hash->table = calloc(hashSet->size, sizeof(GlyphRefRec));
     if (!hash->table)
         return FALSE;