diff --git a/src/cst/always_statement.rs b/src/cst/always_statement.rs
index 39d1827..df8034b 100644
--- a/src/cst/always_statement.rs
+++ b/src/cst/always_statement.rs
@@ -243,7 +243,6 @@ impl AlwaysStatement {
                 let prb = builder.ins().prb(val);
 
                 context.syntax_table.insert_value(builder.unit(), val, json);
-                context.syntax_table.insert_value(builder.unit(), prb, json);
 
                 let (name, event) = {
                     let (mut n, v) = match *tag {