Fix expr_to_spanned_string ICE

compiler/rustc_expand/src/base.rs

@@ -16,6 +16,7 @@ use rustc_errors::{
 use rustc_lint_defs::builtin::PROC_MACRO_BACK_COMPAT;
 use rustc_lint_defs::{BufferedEarlyLint, BuiltinLintDiagnostics};
 use rustc_parse::{self, parser, MACRO_ARGUMENTS};
+use rustc_session::errors::report_lit_error;
 use rustc_session::{parse::ParseSess, Limit, Session};
 use rustc_span::def_id::{CrateNum, DefId, LocalDefId};
 use rustc_span::edition::Edition;
@@ -1245,7 +1246,10 @@ pub fn expr_to_spanned_string<'a>(
                 Some((err, true))
             }
             Ok(ast::LitKind::Err) => None,
-            Err(_) => None,
+            Err(err) => {
+                report_lit_error(&cx.sess.parse_sess, err, token_lit, expr.span);
+                None
+            }
             _ => Some((cx.struct_span_err(expr.span, err_msg), false)),
         },
         ast::ExprKind::Err => None,

compiler/rustc_session/src/errors.rs

@@ -197,12 +197,12 @@ pub enum UnleashedFeatureHelp {
 
 #[derive(Diagnostic)]
 #[diag(session_invalid_literal_suffix)]
-pub(crate) struct InvalidLiteralSuffix {
+pub(crate) struct InvalidLiteralSuffix<'a> {
     #[primary_span]
     #[label]
     pub span: Span,
     // FIXME(#100717)
-    pub kind: String,
+    pub kind: &'a str,
     pub suffix: Symbol,
 }
 
@@ -311,11 +311,7 @@ pub fn report_lit_error(sess: &ParseSess, err: LitError, lit: token::Lit, span:
         LitError::LexerError => {}
         LitError::InvalidSuffix => {
             if let Some(suffix) = suffix {
-                sess.emit_err(InvalidLiteralSuffix {
-                    span,
-                    kind: format!("{}", kind.descr()),
-                    suffix,
-                });
+                sess.emit_err(InvalidLiteralSuffix { span, kind: kind.descr(), suffix });
             }
         }
         LitError::InvalidIntSuffix => {

src/test/ui/macros/issue-105011.rs

@@ -0,0 +1,3 @@
+fn main() {
+    println!(""y); //~ ERROR suffixes on string literals are invalid
+}

src/test/ui/macros/issue-105011.stderr

@@ -0,0 +1,8 @@
+error: suffixes on string literals are invalid
+  --> $DIR/issue-105011.rs:2:14
+   |
+LL |     println!(""y);
+   |              ^^^ invalid suffix `y`
+
+error: aborting due to previous error
+