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src/modules.rs

@@ -47,6 +47,9 @@ fn path_value(attr: &ast::Attribute) -> Option<Symbol> {
     }
 }
 
+// N.B. Even when there are multiple `#[path = ...]` attributes, we just need to
+// examine the first one, since rustc ignores the second and the subsequent ones
+// as unused attributes.
 fn find_path_value(attrs: &[ast::Attribute]) -> Option<Symbol> {
     attrs.iter().flat_map(path_value).next()
 }