From c6216da9bedc4beebdeb5876726691f75d55dd76 Mon Sep 17 00:00:00 2001
From: Giulio Eulisse <10544+ktf@users.noreply.github.com>
Date: Wed, 21 Jan 2026 16:55:11 +0100
Subject: [PATCH] DPL: make new early forward optional

The new behavior breaks the TPC custom policy.
---
 Framework/Core/src/DataProcessingDevice.cxx | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Framework/Core/src/DataProcessingDevice.cxx b/Framework/Core/src/DataProcessingDevice.cxx
index 38c57c66c8a01..fb54af9402079 100644
--- a/Framework/Core/src/DataProcessingDevice.cxx
+++ b/Framework/Core/src/DataProcessingDevice.cxx
@@ -1054,7 +1054,11 @@ void DataProcessingDevice::fillContext(DataProcessorContext& context, DeviceCont
   }
 
   auto decideEarlyForward = [&context, &deviceContext, &spec, this]() -> ForwardPolicy {
-    ForwardPolicy defaultEarlyForwardPolicy = getenv("DPL_OLD_EARLY_FORWARD") ? ForwardPolicy::AtCompletionPolicySatisified : ForwardPolicy::AtInjection;
+    //ForwardPolicy defaultEarlyForwardPolicy = getenv("DPL_OLD_EARLY_FORWARD") ? ForwardPolicy::AtCompletionPolicySatisified : ForwardPolicy::AtInjection;
+    // Make the new policy optional until we handle some of the corner cases
+    // with custom policies which expect the early forward to happen only when
+    // all the data is available, like in the TPC case.
+    ForwardPolicy defaultEarlyForwardPolicy = getenv("DPL_NEW_EARLY_FORWARD") ? ForwardPolicy::AtInjection : ForwardPolicy::AtCompletionPolicySatisified;
 
     /// We must make sure there is no optional
     /// if we want to optimize the forwarding