add FIXME rust-lang#32753 markers: SVH vs ICH

Author: nikomatsakis

src/librustc_incremental/calculate_svh.rs

@@ -44,8 +44,10 @@ impl<'tcx> SvhCalculate for ty::TyCtxt<'tcx> {
         let mut state = SipHasher::new();
         debug!("state: {:?}", state);
 
+        // FIXME(#32753) -- at (*) we `to_le` for endianness, but is
+        // this enough, and does it matter anyway?
         "crate_disambiguator".hash(&mut state);
-        crate_disambiguator.as_str().len().hash(&mut state);
+        crate_disambiguator.as_str().len().to_le().hash(&mut state); // (*)
         crate_disambiguator.as_str().hash(&mut state);
 
         debug!("crate_disambiguator: {:?}", crate_disambiguator.as_str());

src/librustc_incremental/persist/load.rs

@@ -151,6 +151,7 @@ fn initial_dirty_nodes<'tcx>(tcx: &ty::TyCtxt<'tcx>,
     for hashed_item in hashed_items {
         match retraced.def_id(hashed_item.index) {
             Some(def_id) => {
+                // FIXME(#32753) -- should we use a distinct hash here
                 let current_hash = tcx.calculate_item_hash(def_id);
                 debug!("initial_dirty_nodes: hash of {:?} is {:?}, was {:?}",
                        def_id, current_hash, hashed_item.hash);

src/librustc_incremental/persist/save.rs

@@ -93,6 +93,7 @@ pub fn encode_dep_graph<'tcx>(tcx: &ty::TyCtxt<'tcx>,
                      assert!(def_id.is_local());
                      builder.add(def_id)
                             .map(|index| {
+                                // FIXME(#32753) -- should we use a distinct hash here
                                 let hash = tcx.calculate_item_hash(def_id);
                                 SerializedHash { index: index, hash: hash }
                             })