diff --git a/crypto/obj/obj.c b/crypto/obj/obj.c
index 4f03c59..3bf1abf 100644
--- a/crypto/obj/obj.c
+++ b/crypto/obj/obj.c
@@ -189,7 +189,7 @@
 // an |ASN1_OBJECT|* that we're looking for and |element| is a pointer to an
 // unsigned int in the array.
 static int obj_cmp(const void *key, const void *element) {
-  unsigned nid = *((const unsigned*) element);
+  uint16_t nid = *((const uint16_t *)element);
   const ASN1_OBJECT *a = key;
   const ASN1_OBJECT *b = &kObjects[nid];
 
@@ -202,8 +202,6 @@
 }
 
 int OBJ_obj2nid(const ASN1_OBJECT *obj) {
-  const unsigned int *nid_ptr;
-
   if (obj == NULL) {
     return NID_undef;
   }
@@ -224,8 +222,9 @@
   }
   CRYPTO_STATIC_MUTEX_unlock_read(&global_added_lock);
 
-  nid_ptr = bsearch(obj, kNIDsInOIDOrder, OPENSSL_ARRAY_SIZE(kNIDsInOIDOrder),
-                    sizeof(kNIDsInOIDOrder[0]), obj_cmp);
+  const uint16_t *nid_ptr =
+      bsearch(obj, kNIDsInOIDOrder, OPENSSL_ARRAY_SIZE(kNIDsInOIDOrder),
+              sizeof(kNIDsInOIDOrder[0]), obj_cmp);
   if (nid_ptr == NULL) {
     return NID_undef;
   }
@@ -250,15 +249,13 @@
 // |key| argument is name that we're looking for and |element| is a pointer to
 // an unsigned int in the array.
 static int short_name_cmp(const void *key, const void *element) {
-  const char *name = (const char *) key;
-  unsigned nid = *((unsigned*) element);
+  const char *name = (const char *)key;
+  uint16_t nid = *((const uint16_t *)element);
 
   return strcmp(name, kObjects[nid].sn);
 }
 
 int OBJ_sn2nid(const char *short_name) {
-  const unsigned int *nid_ptr;
-
   CRYPTO_STATIC_MUTEX_lock_read(&global_added_lock);
   if (global_added_by_short_name != NULL) {
     ASN1_OBJECT *match, template;
@@ -272,9 +269,10 @@
   }
   CRYPTO_STATIC_MUTEX_unlock_read(&global_added_lock);
 
-  nid_ptr = bsearch(short_name, kNIDsInShortNameOrder,
-                    OPENSSL_ARRAY_SIZE(kNIDsInShortNameOrder),
-                    sizeof(kNIDsInShortNameOrder[0]), short_name_cmp);
+  const uint16_t *nid_ptr =
+      bsearch(short_name, kNIDsInShortNameOrder,
+              OPENSSL_ARRAY_SIZE(kNIDsInShortNameOrder),
+              sizeof(kNIDsInShortNameOrder[0]), short_name_cmp);
   if (nid_ptr == NULL) {
     return NID_undef;
   }
@@ -286,15 +284,13 @@
 // |key| argument is name that we're looking for and |element| is a pointer to
 // an unsigned int in the array.
 static int long_name_cmp(const void *key, const void *element) {
-  const char *name = (const char *) key;
-  unsigned nid = *((unsigned*) element);
+  const char *name = (const char *)key;
+  uint16_t nid = *((const uint16_t *)element);
 
   return strcmp(name, kObjects[nid].ln);
 }
 
 int OBJ_ln2nid(const char *long_name) {
-  const unsigned int *nid_ptr;
-
   CRYPTO_STATIC_MUTEX_lock_read(&global_added_lock);
   if (global_added_by_long_name != NULL) {
     ASN1_OBJECT *match, template;
@@ -308,9 +304,9 @@
   }
   CRYPTO_STATIC_MUTEX_unlock_read(&global_added_lock);
 
-  nid_ptr = bsearch(long_name, kNIDsInLongNameOrder,
-                    OPENSSL_ARRAY_SIZE(kNIDsInLongNameOrder),
-                    sizeof(kNIDsInLongNameOrder[0]), long_name_cmp);
+  const uint16_t *nid_ptr = bsearch(
+      long_name, kNIDsInLongNameOrder, OPENSSL_ARRAY_SIZE(kNIDsInLongNameOrder),
+      sizeof(kNIDsInLongNameOrder[0]), long_name_cmp);
   if (nid_ptr == NULL) {
     return NID_undef;
   }
diff --git a/crypto/obj/obj_dat.h b/crypto/obj/obj_dat.h
index 53198f9..d472ba5 100644
--- a/crypto/obj/obj_dat.h
+++ b/crypto/obj/obj_dat.h
@@ -8763,7 +8763,7 @@
     {"ED448", "ED448", NID_ED448, 3, &kObjectData[6178], 0},
 };
 
-static const unsigned kNIDsInShortNameOrder[] = {
+static const uint16_t kNIDsInShortNameOrder[] = {
     364 /* AD_DVCS */,
     419 /* AES-128-CBC */,
     916 /* AES-128-CBC-HMAC-SHA1 */,
@@ -9717,7 +9717,7 @@
     160 /* x509Crl */,
 };
 
-static const unsigned kNIDsInLongNameOrder[] = {
+static const uint16_t kNIDsInLongNameOrder[] = {
     363 /* AD Time Stamping */,
     405 /* ANSI X9.62 */,
     368 /* Acceptable OCSP Responses */,
@@ -10671,7 +10671,7 @@
     125 /* zlib compression */,
 };
 
-static const unsigned kNIDsInOIDOrder[] = {
+static const uint16_t kNIDsInOIDOrder[] = {
     434 /* 0.9 (OBJ_data) */,
     182 /* 1.2 (OBJ_member_body) */,
     676 /* 1.3 (OBJ_identified_organization) */,
diff --git a/crypto/obj/objects.go b/crypto/obj/objects.go
index 28887c0..361cdfe 100644
--- a/crypto/obj/objects.go
+++ b/crypto/obj/objects.go
@@ -347,6 +347,11 @@
 		return nil, err
 	}
 
+	// The kNIDsIn*Order constants assume each NID fits in a uint16_t.
+	if len(objs.byNID) > 0xffff {
+		return nil, errors.New("too many NIDs allocated")
+	}
+
 	return objs, nil
 }
 
@@ -645,7 +650,7 @@
 	}
 	sortNIDs(nids, objs, func(a, b object) bool { return a.shortName < b.shortName })
 
-	fmt.Fprintf(&b, "\nstatic const unsigned kNIDsInShortNameOrder[] = {\n")
+	fmt.Fprintf(&b, "\nstatic const uint16_t kNIDsInShortNameOrder[] = {\n")
 	for _, nid := range nids {
 		fmt.Fprintf(&b, "%d /* %s */,\n", nid, objs.byNID[nid].shortName)
 	}
@@ -661,7 +666,7 @@
 	}
 	sortNIDs(nids, objs, func(a, b object) bool { return a.longName < b.longName })
 
-	fmt.Fprintf(&b, "\nstatic const unsigned kNIDsInLongNameOrder[] = {\n")
+	fmt.Fprintf(&b, "\nstatic const uint16_t kNIDsInLongNameOrder[] = {\n")
 	for _, nid := range nids {
 		fmt.Fprintf(&b, "%d /* %s */,\n", nid, objs.byNID[nid].longName)
 	}
@@ -686,7 +691,7 @@
 		return bytes.Compare(a.encoded, b.encoded) < 0
 	})
 
-	fmt.Fprintf(&b, "\nstatic const unsigned kNIDsInOIDOrder[] = {\n")
+	fmt.Fprintf(&b, "\nstatic const uint16_t kNIDsInOIDOrder[] = {\n")
 	for _, nid := range nids {
 		obj := objs.byNID[nid]
 		fmt.Fprintf(&b, "%d /* ", nid)