diff --git a/src/Attr.cc b/src/Attr.cc
index 0c134606fb..6850c80b5f 100644
--- a/src/Attr.cc
+++ b/src/Attr.cc
@@ -22,7 +22,7 @@ const char* attr_name(AttrTag t)
 		"&group", "&log", "&error_handler", "&type_column",
 		"(&tracked)", "&on_change", "&broker_store",
 		"&broker_allow_complex_type", "&backend", "&deprecated",
-		"&is_set",
+		"&is_assigned", "&is_used",
 	};
 
 	return attr_names[int(t)];
@@ -291,6 +291,7 @@ void Attributes::CheckAttr(Attr* a)
 	case ATTR_DEPRECATED:
 	case ATTR_REDEF:
 	case ATTR_IS_ASSIGNED:
+	case ATTR_IS_USED:
 		break;
 
 	case ATTR_OPTIONAL:
diff --git a/src/Attr.h b/src/Attr.h
index c63b0adacc..bd6d349387 100644
--- a/src/Attr.h
+++ b/src/Attr.h
@@ -46,7 +46,8 @@ enum AttrTag {
 	ATTR_BROKER_STORE_ALLOW_COMPLEX, // for Broker store backed tables
 	ATTR_BACKEND, // for Broker store backed tables
 	ATTR_DEPRECATED,
-	ATTR_IS_ASSIGNED, // to suppress warnings
+	ATTR_IS_ASSIGNED, // to suppress usage warnings
+	ATTR_IS_USED, // to suppress usage warnings
 	NUM_ATTRS // this item should always be last
 };
 
diff --git a/src/parse.y b/src/parse.y
index 11c168541f..d8ce7ec819 100644
--- a/src/parse.y
+++ b/src/parse.y
@@ -5,7 +5,7 @@
 // Switching parser table type fixes ambiguity problems.
 %define lr.type ielr
 
-%expect 135
+%expect 141
 
 %token TOK_ADD TOK_ADD_TO TOK_ADDR TOK_ANY
 %token TOK_ATENDIF TOK_ATELSE TOK_ATIF TOK_ATIFDEF TOK_ATIFNDEF
@@ -28,7 +28,7 @@
 %token TOK_ATTR_BROKER_STORE_ALLOW_COMPLEX TOK_ATTR_BACKEND
 %token TOK_ATTR_PRIORITY TOK_ATTR_LOG TOK_ATTR_ERROR_HANDLER
 %token TOK_ATTR_TYPE_COLUMN TOK_ATTR_DEPRECATED
-%token TOK_ATTR_IS_ASSIGNED
+%token TOK_ATTR_IS_ASSIGNED TOK_ATTR_IS_USED
 
 %token TOK_DEBUG
 
@@ -1474,6 +1474,8 @@ attr:
 			{ $$ = new zeek::detail::Attr(zeek::detail::ATTR_REDEF); }
 	|	TOK_ATTR_IS_ASSIGNED
 			{ $$ = new zeek::detail::Attr(zeek::detail::ATTR_IS_ASSIGNED); }
+	|	TOK_ATTR_IS_USED
+			{ $$ = new zeek::detail::Attr(zeek::detail::ATTR_IS_USED); }
 	|	TOK_ATTR_ADD_FUNC '=' expr
 			{ $$ = new zeek::detail::Attr(zeek::detail::ATTR_ADD_FUNC, {zeek::AdoptRef{}, $3}); }
 	|	TOK_ATTR_DEL_FUNC '=' expr
diff --git a/src/scan.l b/src/scan.l
index da512f4206..198843fe83 100644
--- a/src/scan.l
+++ b/src/scan.l
@@ -286,6 +286,7 @@ when	return TOK_WHEN;
 &log		return TOK_ATTR_LOG;
 &optional	return TOK_ATTR_OPTIONAL;
 &is_assigned	return TOK_ATTR_IS_ASSIGNED;
+&is_used	return TOK_ATTR_IS_USED;
 &priority	return TOK_ATTR_PRIORITY;
 &type_column	return TOK_ATTR_TYPE_COLUMN;
 &read_expire	return TOK_ATTR_EXPIRE_READ;