added error handle for error code > 9999

Author: Kivooeo

compiler/rustc_driver_impl/src/lib.rs

@@ -462,7 +462,9 @@ pub enum Compilation {
 fn handle_explain(early_dcx: &EarlyDiagCtxt, registry: Registry, code: &str, color: ColorConfig) {
     // Allow "E0123" or "0123" form.
     let upper_cased_code = code.to_ascii_uppercase();
-    if let Ok(code) = upper_cased_code.strip_prefix('E').unwrap_or(&upper_cased_code).parse::<u32>()
+    let result_code =
+        upper_cased_code.strip_prefix('E').unwrap_or(&upper_cased_code).parse::<u32>();
+    if let Ok(code) = result_code
         && let Ok(description) = registry.try_find_description(ErrCode::from_u32(code))
     {
         let mut is_in_code_block = false;
@@ -487,6 +489,11 @@ fn handle_explain(early_dcx: &EarlyDiagCtxt, registry: Registry, code: &str, col
         } else {
             safe_print!("{text}");
         }
+    } else if let Ok(code) = result_code
+        && code > 9999
+    {
+        early_dcx
+            .early_fatal(format!("{upper_cased_code} exceeds the maximum allowed value (E9999)"));
     } else {
         early_dcx.early_fatal(format!("{code} is not a valid error code"));
     }

compiler/rustc_errors/src/codes.rs

@@ -7,7 +7,6 @@
 use std::fmt;
 
 rustc_index::newtype_index! {
-    #[max = 9999] // Because all error codes have four digits.
     #[orderable]
     #[encodable]
     #[debug_format = "ErrCode({})"]