removed eprintln

Author: KMJ-007

compiler/rustc_session/src/options.rs

@@ -1364,9 +1364,6 @@ pub mod parse {
                     if let Some(fun) = arg {
                         AutoDiff::PrintTAFn(fun.to_string())
                     } else {
-                        eprintln!(
-                            "Missing argument for PrintTAFn (expected PrintTAFn=<function_name>)"
-                        );
                         return false;
                     }
                 }
@@ -1380,10 +1377,7 @@ pub mod parse {
                 "PrintPasses" => AutoDiff::PrintPasses,
                 "LooseTypes" => AutoDiff::LooseTypes,
                 "Inline" => AutoDiff::Inline,
-                _ => {
-                    eprintln!("Unknown autodiff option: {key}");
-                    return false;
-                }
+                _ => return false,
             };
             slot.push(variant);
         }