diff --git a/src/libutil/hash.cc b/src/libutil/hash.cc
index 01fae3044..1a3e7c5d8 100644
--- a/src/libutil/hash.cc
+++ b/src/libutil/hash.cc
@@ -370,7 +370,7 @@ string printHashType(HashType ht)
     default:
         // illegal hash type enum value internally, as opposed to external input
         // which should be validated with nice error message.
-        abort();
+        assert(false);
     }
 }
 
diff --git a/src/nix/develop.cc b/src/nix/develop.cc
index 037987313..289e3bed3 100644
--- a/src/nix/develop.cc
+++ b/src/nix/develop.cc
@@ -135,13 +135,7 @@ StorePath getDerivationEnvironment(ref<Store> store, const StorePath & drvPath)
     drv.inputSrcs.insert(std::move(getEnvShPath));
     Hash h = hashDerivationModulo(*store, drv, true);
     auto shellOutPath = store->makeOutputPath("out", h, drvName);
-    drv.outputs.insert_or_assign("out", DerivationOutput {
-        .path = shellOutPath,
-        .hash = FixedOutputHash {
-            .method = FileIngestionMethod::Flat,
-            .hash = Hash { },
-        },
-    });
+    drv.outputs.insert_or_assign("out", DerivationOutput { .path = shellOutPath });
     drv.env["out"] = store->printStorePath(shellOutPath);
     auto shellDrvPath2 = writeDerivation(store, drv, drvName);