Merge pull request #515 from ethereum/fix-fetching-rpc

Fixing fetching RPC

CHANGELOG.md

@@ -23,6 +23,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - PAnd props are now recursively flattened
 - Double negation in Prop are removed
 - Updated forge to modern version, thereby fixing JSON parsing of new forge JSONs
+- Fixed RPC fetching of contract data
 - Symbolic ABI encoding for tuples, fuzzer for encoder
 - Printing `Addrs` when running `symbolic` for counterexamples and reachable end states
 - Improved symbolic execution tutorial

src/EVM.hs

@@ -1426,13 +1426,13 @@ accessStorage addr slot continue = do
       fetchAccount addr $ \_ ->
         accessStorage addr slot continue
   where
-      rpcCall c slotConc = if c.external
+      rpcCall c slotConc = fetchAccount addr $ \_ ->
+        if c.external
         then forceConcreteAddr addr "cannot read storage from symbolic addresses via rpc" $ \addr' ->
           forceConcrete slotConc "cannot read symbolic slots via RPC" $ \slot' -> do
             -- check if the slot is cached
-            contract <- preuse (#cache % #fetched % ix addr')
-            case contract of
-              Nothing -> internalError "contract marked external not found in cache"
+            use (#env % #contracts % at (LitAddr addr')) >>= \case
+              Nothing -> internalError $ "contract addr " <> show addr' <> " marked external not found in cache"
               Just fetched -> case readStorage (Lit slot') fetched.storage of
                           Nothing -> mkQuery addr' slot'
                           Just val -> continue val