Auto merge of rust-lang#139594 - compiler-errors:if-cause, r=<try>

[experiment] How expensive is `if_cause`?

TODO

r? `@ghost`

Author: bors

compiler/rustc_hir_typeck/src/_match.rs

@@ -420,6 +420,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         else_ty: Ty<'tcx>,
         tail_defines_return_position_impl_trait: Option<LocalDefId>,
     ) -> ObligationCause<'tcx> {
+        if true {
+            return self.misc(span);
+        }
+
         let mut outer_span = if self.tcx.sess.source_map().is_multiline(span) {
             // The `if`/`else` isn't in one line in the output, include some context to make it
             // clear it is an if/else expression: