normalize field projection ty to fix broken MIR issue

Author: spastorino

src/librustc_mir/borrow_check/type_check/mod.rs

@@ -686,6 +686,7 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                 let fty = self.sanitize_type(place, fty);
                 match self.field_ty(place, base, field, location) {
                     Ok(ty) => {
+                        let ty = self.cx.normalize(ty, location);
                         if let Err(terr) = self.cx.eq_types(
                             ty,
                             fty,

src/test/ui/consts/issue-70773-mir-typeck-lt-norm.rs

@@ -7,6 +7,7 @@ fn init_hash(_: &mut [u8; HASH_LEN]) {}
 fn foo<'a>() -> &'a () {
     Hash([0; HASH_LEN]);
     init_hash(&mut [0; HASH_LEN]);
+    let (_array,) = ([0; HASH_LEN],);
     &()
 }