diff --git a/src/Expr.cc b/src/Expr.cc
index 2876369145..eecc2aa3a2 100644
--- a/src/Expr.cc
+++ b/src/Expr.cc
@@ -3921,7 +3921,7 @@ ValPtr RecordCoerceExpr::Fold(Val* v) const
 			if ( ! rhs )
 				{
 				// Optional field is missing.
-				val->Assign(i, nullptr);
+				val->Remove(i);
 				continue;
 				}
 
@@ -3968,7 +3968,7 @@ ValPtr RecordCoerceExpr::Fold(Val* v) const
 				val->Assign(i, std::move(def_val));
 				}
 			else
-				val->Assign(i, nullptr);
+				val->Remove(i);
 			}
 		}
 
diff --git a/src/analyzer/protocol/rpc/MOUNT.cc b/src/analyzer/protocol/rpc/MOUNT.cc
index c321486cb8..d857d37288 100644
--- a/src/analyzer/protocol/rpc/MOUNT.cc
+++ b/src/analyzer/protocol/rpc/MOUNT.cc
@@ -272,11 +272,6 @@ RecordValPtr MOUNT_Interp::mount3_mnt_reply(const u_char*& buf, int& n,
 
 		rep->Assign(1, std::move(auth_flavors));
 		}
-	else
-		{
-		rep->Assign(0, nullptr);
-		rep->Assign(1, nullptr);
-		}
 
 	return rep;
 	}
diff --git a/src/analyzer/protocol/rpc/NFS.cc b/src/analyzer/protocol/rpc/NFS.cc
index 856a1b6254..589f3ac1bd 100644
--- a/src/analyzer/protocol/rpc/NFS.cc
+++ b/src/analyzer/protocol/rpc/NFS.cc
@@ -353,22 +353,18 @@ RecordValPtr NFS_Interp::nfs3_sattr(const u_char*& buf, int& n)
 	{
 	auto attrs = make_intrusive<RecordVal>(BifType::Record::NFS3::sattr_t);
 
-	attrs->Assign(0, nullptr); // mode
 	int mode_set_it =  extract_XDR_uint32(buf, n);
 	if ( mode_set_it )
 		attrs->Assign(0, ExtractUint32(buf, n)); // mode
 
-	attrs->Assign(1, nullptr); // uid
 	int uid_set_it =  extract_XDR_uint32(buf, n);
 	if ( uid_set_it )
 		attrs->Assign(1, ExtractUint32(buf, n)); // uid
 
-	attrs->Assign(2, nullptr); // gid
 	int gid_set_it =  extract_XDR_uint32(buf, n);
 	if ( gid_set_it )
 		attrs->Assign(2, ExtractUint32(buf, n)); // gid
 
-	attrs->Assign(3, nullptr); // size
 	int size_set_it =  extract_XDR_uint32(buf, n);
 	if ( size_set_it )
 		attrs->Assign(3, ExtractTime(buf, n));	 // size
@@ -389,11 +385,6 @@ RecordValPtr NFS_Interp::nfs3_sattr_reply(const u_char*& buf, int& n, BifEnum::N
 		rep->Assign(0, nfs3_pre_op_attr(buf, n));
 		rep->Assign(1, nfs3_post_op_attr(buf, n));
 		}
-	else
-		{
-		rep->Assign(1, nullptr);
-		rep->Assign(2, nullptr);
-		}
 
 	return rep;
 	}
@@ -536,8 +527,6 @@ RecordValPtr NFS_Interp::nfs3_lookup_reply(const u_char*& buf, int& n, BifEnum::
 		}
 	else
 		{
-		rep->Assign(0, nullptr);
-		rep->Assign(1, nullptr);
 		rep->Assign(2, nfs3_post_op_attr(buf, n));
 		}
 	return rep;
@@ -698,8 +687,6 @@ RecordValPtr NFS_Interp::nfs3_newobj_reply(const u_char*& buf, int& n, BifEnum::
 		}
 	else
 		{
-		rep->Assign(0, nullptr);
-		rep->Assign(1, nullptr);
 		rep->Assign(2, nfs3_pre_op_attr(buf, n));
 		rep->Assign(3, nfs3_post_op_attr(buf, n));
 		}
diff --git a/src/broker/Data.cc b/src/broker/Data.cc
index d8d03c709d..a54e30287c 100644
--- a/src/broker/Data.cc
+++ b/src/broker/Data.cc
@@ -430,7 +430,7 @@ struct val_converter {
 
 				if ( caf::get_if<broker::none>(&a[idx]) != nullptr )
 					{
-					rval->Assign(i, nullptr);
+					rval->Remove(i);
 					++idx;
 					continue;
 					}
diff --git a/src/broker/Manager.cc b/src/broker/Manager.cc
index 656da437af..07bca256f6 100644
--- a/src/broker/Manager.cc
+++ b/src/broker/Manager.cc
@@ -793,7 +793,7 @@ RecordVal* Manager::MakeEvent(ValPList* args, zeek::detail::Frame* frame)
 
 		if ( ! same_type(got_type, expected_type) )
 			{
-			rval->Assign(0, nullptr);
+			rval->Remove(0);
 			Error("event parameter #%d type mismatch, got %s, expect %s", i,
 			      type_name(got_type->Tag()),
 			      type_name(expected_type->Tag()));
@@ -809,7 +809,7 @@ RecordVal* Manager::MakeEvent(ValPList* args, zeek::detail::Frame* frame)
 
 		if ( ! data_val->HasField(0) )
 			{
-			rval->Assign(0, nullptr);
+			rval->Remove(0);
 			Error("failed to convert param #%d of type %s to broker data",
 				  i, type_name(got_type->Tag()));
 			return rval;