Print correct base for too-large literals

Also update tests

1 files changed, 10 insertions, 2 deletions

diff --git a/compiler/rustc_session/src/errors.rs b/compiler/rustc_session/src/errors.rs
index effb561688c..f5a72573d58 100644
--- a/compiler/rustc_session/src/errors.rs
+++ b/compiler/rustc_session/src/errors.rs
@@ -264,6 +264,7 @@ pub(crate) struct InvalidFloatLiteralSuffix {
 pub(crate) struct IntLiteralTooLarge {
     #[primary_span]
     pub span: Span,
+    pub limit: String,
 }
 
 #[derive(Diagnostic)]
@@ -362,8 +363,15 @@ pub fn report_lit_error(sess: &ParseSess, err: LitError, lit: token::Lit, span:
                 _ => unreachable!(),
             };
         }
-        LitError::IntTooLarge => {
-            sess.emit_err(IntLiteralTooLarge { span });
+        LitError::IntTooLarge(base) => {
+            let max = u128::MAX;
+            let limit = match base {
+                2 => format!("{max:#b}"),
+                8 => format!("{max:#o}"),
+                16 => format!("{max:#x}"),
+                _ => format!("{max}"),
+            };
+            sess.emit_err(IntLiteralTooLarge { span, limit });
         }
     }
 }