Note maximum integer literal for IntLiteralTooLarge

Author: clubby789

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

@@ -85,6 +85,7 @@ session_invalid_float_literal_suffix = invalid suffix `{$suffix}` for float lite
     .help = valid suffixes are `f32` and `f64`
 
 session_int_literal_too_large = integer literal is too large
+    .note = value exceeds limit of 340282366920938463463374607431768211455
 
 session_invalid_int_literal_width = invalid width `{$width}` for integer literal
     .help = valid widths are 8, 16, 32, 64 and 128

compiler/rustc_session/src/errors.rs

@@ -260,6 +260,7 @@ pub(crate) struct InvalidFloatLiteralSuffix {
 
 #[derive(Diagnostic)]
 #[diag(session_int_literal_too_large)]
+#[note]
 pub(crate) struct IntLiteralTooLarge {
     #[primary_span]
     pub span: Span,