Migrate typeck's used expected symbol diagnostic to SessionDiagnostic

compiler/rustc_error_messages/locales/en-US/typeck.ftl

@@ -131,3 +131,5 @@ typeck_unused_extern_crate =
 typeck_extern_crate_not_idiomatic =
     `extern crate` is not idiomatic in the new edition
     .suggestion = convert it to a `{$msg_code}`
+
+typeck_expected_used_symbol = expected `used`, `used(compiler)` or `used(linker)`

compiler/rustc_typeck/src/collect.rs

@@ -2836,12 +2836,7 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: DefId) -> CodegenFnAttrs {
                     codegen_fn_attrs.flags |= CodegenFnAttrFlags::USED;
                 }
                 Some(_) => {
-                    tcx.sess
-                        .struct_span_err(
-                            attr.span,
-                            "expected `used`, `used(compiler)` or `used(linker)`",
-                        )
-                        .emit();
+                    tcx.sess.emit_err(errors::ExpectedUsedSymbol { span: attr.span });
                 }
                 None => {
                     // Unfortunately, unconditionally using `llvm.used` causes

compiler/rustc_typeck/src/errors.rs

@@ -340,3 +340,10 @@ pub struct ExternCrateNotIdiomatic {
     pub msg_code: String,
     pub suggestion_code: String,
 }
+
+#[derive(SessionDiagnostic)]
+#[error(typeck::expected_used_symbol)]
+pub struct ExpectedUsedSymbol {
+    #[primary_span]
+    pub span: Span,
+}