diff --git a/v2/accounting/marshal.go b/v2/accounting/marshal.go
index 684599f9..e25ab909 100644
--- a/v2/accounting/marshal.go
+++ b/v2/accounting/marshal.go
@@ -36,7 +36,7 @@ func (d *Decimal) StableMarshal(buf []byte) ([]byte, error) {
 
 	offset += n
 
-	n, err = protoutil.UInt32Marshal(decimalPrecisionField, buf[offset:], d.prec)
+	_, err = protoutil.UInt32Marshal(decimalPrecisionField, buf[offset:], d.prec)
 	if err != nil {
 		return nil, err
 	}
diff --git a/v2/audit/marshal.go b/v2/audit/marshal.go
index f1a0c599..5ea8ef51 100644
--- a/v2/audit/marshal.go
+++ b/v2/audit/marshal.go
@@ -132,7 +132,7 @@ func (a *DataAuditResult) StableMarshal(buf []byte) ([]byte, error) {
 
 	offset += n
 
-	n, err = proto.RepeatedBytesMarshal(failNodesFNum, buf[offset:], a.failNodes)
+	_, err = proto.RepeatedBytesMarshal(failNodesFNum, buf[offset:], a.failNodes)
 	if err != nil {
 		return nil, err
 	}
diff --git a/v2/netmap/marshal.go b/v2/netmap/marshal.go
index b619628e..32a6b767 100644
--- a/v2/netmap/marshal.go
+++ b/v2/netmap/marshal.go
@@ -159,7 +159,7 @@ func (s *Selector) StableMarshal(buf []byte) ([]byte, error) {
 
 	offset += n
 
-	n, err = protoutil.StringMarshal(filterSelectorField, buf[offset:], s.filter)
+	_, err = protoutil.StringMarshal(filterSelectorField, buf[offset:], s.filter)
 	if err != nil {
 		return nil, err
 	}
@@ -209,7 +209,7 @@ func (r *Replica) StableMarshal(buf []byte) ([]byte, error) {
 
 	offset += n
 
-	n, err = protoutil.StringMarshal(selectorReplicaField, buf[offset:], r.selector)
+	_, err = protoutil.StringMarshal(selectorReplicaField, buf[offset:], r.selector)
 	if err != nil {
 		return nil, err
 	}
@@ -418,7 +418,7 @@ func (ni *NodeInfo) StableMarshal(buf []byte) ([]byte, error) {
 		offset += n
 	}
 
-	n, err = protoutil.EnumMarshal(stateNodeInfoField, buf[offset:], int32(ni.state))
+	_, err = protoutil.EnumMarshal(stateNodeInfoField, buf[offset:], int32(ni.state))
 	if err != nil {
 		return nil, err
 	}
diff --git a/v2/object/marshal.go b/v2/object/marshal.go
index 59ac0ad9..b836d135 100644
--- a/v2/object/marshal.go
+++ b/v2/object/marshal.go
@@ -168,7 +168,7 @@ func (h *ShortHeader) StableMarshal(buf []byte) ([]byte, error) {
 
 	offset += n
 
-	n, err = proto.NestedStructureMarshal(shortHdrHomoHashField, buf[offset:], h.homoHash)
+	_, err = proto.NestedStructureMarshal(shortHdrHomoHashField, buf[offset:], h.homoHash)
 	if err != nil {
 		return nil, err
 	}
@@ -485,13 +485,11 @@ func (h *HeaderWithSignature) StableMarshal(buf []byte) ([]byte, error) {
 
 	offset += n
 
-	n, err = proto.NestedStructureMarshal(hdrWithSigSignatureField, buf[offset:], h.signature)
+	_, err = proto.NestedStructureMarshal(hdrWithSigSignatureField, buf[offset:], h.signature)
 	if err != nil {
 		return nil, err
 	}
 
-	offset += n
-
 	return buf, nil
 }
 
@@ -840,7 +838,7 @@ func (r *PutObjectPartInit) StableMarshal(buf []byte) ([]byte, error) {
 
 	offset += n
 
-	n, err = proto.UInt32Marshal(putReqInitCopiesNumField, buf[offset:], r.copyNum)
+	_, err = proto.UInt32Marshal(putReqInitCopiesNumField, buf[offset:], r.copyNum)
 	if err != nil {
 		return nil, err
 	}
diff --git a/v2/storagegroup/marshal.go b/v2/storagegroup/marshal.go
index c7d4e75a..f7b1ed15 100644
--- a/v2/storagegroup/marshal.go
+++ b/v2/storagegroup/marshal.go
@@ -51,7 +51,7 @@ func (s *StorageGroup) StableMarshal(buf []byte) ([]byte, error) {
 
 	offset += n
 
-	n, err = refs.ObjectIDNestedListMarshal(objectIDsField, buf[offset:], s.members)
+	_, err = refs.ObjectIDNestedListMarshal(objectIDsField, buf[offset:], s.members)
 	if err != nil {
 		return nil, err
 	}