diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index c733dc5..a4b150c 100644
--- a/src/ldso/dynlink.c
+++ b/src/ldso/dynlink.c
@@ -138,6 +138,7 @@ static Sym *sysv_lookup(const char *s, uint32_t h, struct dso *dso)
 	return 0;
 }
 
+#define BWSZ (sizeof(size_t)*8)
 static Sym *gnu_lookup(const char *s, uint32_t h1, struct dso *dso)
 {
 	Sym *sym;
@@ -145,10 +146,15 @@ static Sym *gnu_lookup(const char *s, uint32_t h1, struct dso *dso)
 	uint32_t *hashtab = dso->ghashtab;
 	uint32_t nbuckets = hashtab[0];
 	uint32_t *buckets = hashtab + 4 + hashtab[2]*(sizeof(size_t)/4);
-	uint32_t h2;
+	size_t *maskwords = (size_t *)(hashtab + 4);
+	uint32_t h2 = h1 >> hashtab[3];
 	uint32_t *hashval;
-	uint32_t n = buckets[h1 % nbuckets];
+	uint32_t n = (h1/BWSZ) & (hashtab[2]-1);
+	size_t bm = (1 << (h1%BWSZ)) | (1 << (h2%BWSZ));
 
+	if ((maskwords[n] & bm) != bm) return 0;
+
+	n = buckets[h1 % nbuckets];
 	if (!n) return 0;
 
 	strings = dso->strings;