Auto merge of #88865 - guswynn:must_not_suspend, r=oli-obk

[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 013aecae586ca93369917a4e7008377de62e4dbb..92d0470bc2f58ceb92550ad72a12130192b8bb1b 100644 (file)
--- a/compiler/rustc_typeck/src/check/coercion.rs
+++ b/compiler/rustc_typeck/src/check/coercion.rs
@@ -935,11 +935,13 @@ pub fn try_coerce(
         expr_ty: Ty<'tcx>,
         target: Ty<'tcx>,
         allow_two_phase: AllowTwoPhase,
+        cause: Option<ObligationCause<'tcx>>,
     ) -> RelateResult<'tcx, Ty<'tcx>> {
         let source = self.resolve_vars_with_obligations(expr_ty);
         debug!("coercion::try({:?}: {:?} -> {:?})", expr, source, target);
 
-        let cause = self.cause(expr.span, ObligationCauseCode::ExprAssignable);
+        let cause =
+            cause.unwrap_or_else(|| self.cause(expr.span, ObligationCauseCode::ExprAssignable));
         let coerce = Coerce::new(self, cause, allow_two_phase);
         let ok = self.commit_if_ok(|_| coerce.coerce(source, target))?;
 
@@ -1363,7 +1365,13 @@ pub fn coerce_forced_unit<'a>(
                 // Special-case the first expression we are coercing.
                 // To be honest, I'm not entirely sure why we do this.
                 // We don't allow two-phase borrows, see comment in try_find_coercion_lub for why
-                fcx.try_coerce(expression, expression_ty, self.expected_ty, AllowTwoPhase::No)
+                fcx.try_coerce(
+                    expression,
+                    expression_ty,
+                    self.expected_ty,
+                    AllowTwoPhase::No,
+                    Some(cause.clone()),
+                )
             } else {
                 match self.expressions {
                     Expressions::Dynamic(ref exprs) => fcx.try_find_coercion_lub(