re-base and use `OutlivesEnvironment::with_bounds`

[rust.git] / compiler / rustc_typeck / src / check / coercion.rs

diff --git a/compiler/rustc_typeck/src/check/coercion.rs b/compiler/rustc_typeck/src/check/coercion.rs
index 6c6bbfa22e30cab47a4cf5e52b86efb9aeca1df2..def592c46c2e514a4614813094b79fe193deaf3c 100644 (file)
--- a/compiler/rustc_typeck/src/check/coercion.rs
+++ b/compiler/rustc_typeck/src/check/coercion.rs
@@ -1488,14 +1488,14 @@ pub(crate) fn coerce_inner<'a>(
                     // `break`, we want to call the `()` "expected"
                     // since it is implied by the syntax.
                     // (Note: not all force-units work this way.)"
-                    (expression_ty, self.final_ty.unwrap_or(self.expected_ty))
+                    (expression_ty, self.merged_ty())
                 } else {
                     // Otherwise, the "expected" type for error
                     // reporting is the current unification type,
                     // which is basically the LUB of the expressions
                     // we've seen so far (combined with the expected
                     // type)
-                    (self.final_ty.unwrap_or(self.expected_ty), expression_ty)
+                    (self.merged_ty(), expression_ty)
                 };
                 let (expected, found) = fcx.resolve_vars_if_possible((expected, found));
 
@@ -1594,7 +1594,9 @@ fn note_unreachable_loop_return(
         let hir::ExprKind::Loop(_, _, _, loop_span) = expr.kind else { return;};
         let mut span: MultiSpan = vec![loop_span].into();
         span.push_span_label(loop_span, "this might have zero elements to iterate on");
-        for ret_expr in ret_exprs {
+        const MAXITER: usize = 3;
+        let iter = ret_exprs.iter().take(MAXITER);
+        for ret_expr in iter {
             span.push_span_label(
                 ret_expr.span,
                 "if the loop doesn't execute, this value would never get returned",
@@ -1604,6 +1606,12 @@ fn note_unreachable_loop_return(
             span,
             "the function expects a value to always be returned, but loops might run zero times",
         );
+        if MAXITER < ret_exprs.len() {
+            err.note(&format!(
+                "if the loop doesn't execute, {} other values would never get returned",
+                ret_exprs.len() - MAXITER
+            ));
+        }
         err.help(
             "return a value for the case when the loop has zero elements to iterate on, or \
            consider changing the return type to account for that possibility",