Detect bare blocks with type ascription that were meant to be a `struct` literal

Address part of #34255.

Potential improvement: silence the other knock down errors in
`issue-34255-1.rs`.

2 files changed, 2 insertions, 0 deletions

diff --git a/compiler/rustc_builtin_macros/src/deriving/mod.rs b/compiler/rustc_builtin_macros/src/deriving/mod.rs
index 572ec6e242e..bcf95719db5 100644
--- a/compiler/rustc_builtin_macros/src/deriving/mod.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/mod.rs
@@ -102,6 +102,7 @@ fn call_unreachable(cx: &ExtCtxt<'_>, span: Span) -> P<ast::Expr> {
         rules: ast::BlockCheckMode::Unsafe(ast::CompilerGenerated),
         span,
         tokens: None,
+        could_be_bare_literal: false,
     }))
 }
 
diff --git a/compiler/rustc_builtin_macros/src/format.rs b/compiler/rustc_builtin_macros/src/format.rs
index 1dbf7728421..8508b3b7ae6 100644
--- a/compiler/rustc_builtin_macros/src/format.rs
+++ b/compiler/rustc_builtin_macros/src/format.rs
@@ -867,6 +867,7 @@ impl<'a, 'b> Context<'a, 'b> {
             rules: BlockCheckMode::Unsafe(UnsafeSource::CompilerGenerated),
             span: self.macsp,
             tokens: None,
+            could_be_bare_literal: false,
         }));
 
         let ident = Ident::from_str_and_span("args", self.macsp);