diff --git a/pdf.c b/pdf.c
index 0ca63943899675409eb9a1cc3289de56fc925bb9..2f7a46f40b6bea8e7dc879da36f003e8fac4c1fc 100644
--- a/pdf.c
+++ b/pdf.c
@@ -741,7 +741,7 @@ act_xrstm(const HParseResult *p, void *u)
 
 	dict = H_INDEX_TOKEN(p->ast, 1, 0);
 	res = H_FIELD(HParseResult, 1, 1);	// XXX free this
-	xrefs = res ? res->ast : NULL;
+	xrefs = res != NULL ? res->ast : NULL;
 
 	tok = H_MAKE_SEQN(2);
 	tok->seq->elements[0] = (HParsedToken *)xrefs;