move erasedereftemps before statetransform to fix asyncdrop shims generating bad mir

Author: beepster4096

compiler/rustc_mir_transform/src/coroutine.rs

@@ -1646,7 +1646,7 @@ impl<'tcx> crate::MirPass<'tcx> for StateTransform {
         create_coroutine_resume_function(tcx, transform, body, can_return, can_unwind);
 
         // Run derefer to fix Derefs that are not in the first place
-        deref_finder(tcx, body, true);
+        deref_finder(tcx, body, false);
     }
 
     fn is_required(&self) -> bool {

compiler/rustc_mir_transform/src/lib.rs

@@ -616,9 +616,9 @@ fn run_runtime_lowering_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
         // `AddRetag` needs to run after `ElaborateDrops` but before `ElaborateBoxDerefs`.
         // Otherwise it should run fairly late, but before optimizations begin.
         &add_retag::AddRetag,
+        &erase_deref_temps::EraseDerefTemps,
         &elaborate_box_derefs::ElaborateBoxDerefs,
         &coroutine::StateTransform,
-        &erase_deref_temps::EraseDerefTemps,
         &Lint(known_panics_lint::KnownPanicsLint),
     ];
     pm::run_passes_no_validate(tcx, body, passes, Some(MirPhase::Runtime(RuntimePhase::Initial)));