From cc5a1b9b25865f7389fc230f2fb470ebd71cf1e2 Mon Sep 17 00:00:00 2001
From: David Rohr <drohr@jwdt.org>
Date: Wed, 7 May 2025 13:33:27 +0200
Subject: [PATCH] GPU TPC: Do not shift track in Z after the last fit

---
 GPU/GPUTracking/Merger/GPUTPCGMTrackParam.cxx | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/GPU/GPUTracking/Merger/GPUTPCGMTrackParam.cxx b/GPU/GPUTracking/Merger/GPUTPCGMTrackParam.cxx
index 5bd8fd556aa3f..2524c01f0c00b 100644
--- a/GPU/GPUTracking/Merger/GPUTPCGMTrackParam.cxx
+++ b/GPU/GPUTracking/Merger/GPUTPCGMTrackParam.cxx
@@ -407,7 +407,7 @@ GPUd() bool GPUTPCGMTrackParam::Fit(GPUTPCGMMerger* GPUrestrict() merger, int32_
         break; // bad chi2 for the whole track, stop the fit
       }
     }
-    if (((nWays - iWay) & 1) && (clusters[0].sector < 18) == (clusters[maxN - 1].sector < 18)) {
+    if (((nWays - iWay) & 1) && (iWay != nWays - 1) && (clusters[0].sector < 18) == (clusters[maxN - 1].sector < 18)) {
       ShiftZ2(clusters, clustersXYZ, merger, maxN);
     }
   }