diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/syntax_factory/constructors.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/syntax_factory/constructors.rs
index d0f14dafe3f0..c94277f8cf05 100644
--- a/src/tools/rust-analyzer/crates/syntax/src/ast/syntax_factory/constructors.rs
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/syntax_factory/constructors.rs
@@ -896,10 +896,6 @@ pub fn expr_underscore(&self) -> ast::UnderscoreExpr {
             unreachable!()
         };
 
-        if let Some(mut mapping) = self.mappings() {
-            SyntaxMappingBuilder::new(ast.syntax().clone()).finish(&mut mapping);
-        }
-
         ast
     }