From 5a71769431631d0fb60278eadfb15ac1dd51083c Mon Sep 17 00:00:00 2001
From: Giulio Eulisse <10544+ktf@users.noreply.github.com>
Date: Wed, 4 Mar 2026 13:06:58 +0100
Subject: [PATCH] Fix RECC vs PCH interference

Precompiled headers are incompatible with recc because they embed
the path to the original header in the .pch file. This goes against
the idea that a given Action in the cache results in compatible
byproducts.
---
 PWGJE/Tasks/CMakeLists.txt       | 2 ++
 cmake/O2PhysicsAddWorkflow.cmake | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/PWGJE/Tasks/CMakeLists.txt b/PWGJE/Tasks/CMakeLists.txt
index f05c735ef21..68fd3e9bdfb 100644
--- a/PWGJE/Tasks/CMakeLists.txt
+++ b/PWGJE/Tasks/CMakeLists.txt
@@ -11,6 +11,7 @@
 add_library(JetSubstructureHFPCH OBJECT jetSubstructureHFPCH.cxx)
 target_link_libraries(JetSubstructureHFPCH
   PUBLIC O2::Framework O2Physics::PWGJECore O2Physics::AnalysisCore)
+if(NOT DEFINED ENV{USE_RECC})
 target_precompile_headers(JetSubstructureHFPCH PRIVATE
   [["PWGJE/DataModel/Jet.h"]]
   [["PWGJE/DataModel/JetSubstructure.h"]]
@@ -25,6 +26,7 @@ target_precompile_headers(JetSubstructureHFPCH PRIVATE
   <vector>
   <memory>
 )
+endif()
 
 o2physics_add_dpl_workflow(emc-cellmonitor
                     SOURCES emcCellMonitor.cxx
diff --git a/cmake/O2PhysicsAddWorkflow.cmake b/cmake/O2PhysicsAddWorkflow.cmake
index 39d98b2db76..d2d599c4406 100644
--- a/cmake/O2PhysicsAddWorkflow.cmake
+++ b/cmake/O2PhysicsAddWorkflow.cmake
@@ -47,7 +47,7 @@ function(o2physics_add_dpl_workflow baseTargetName)
   set_property(TARGET ${targetExeName} PROPERTY JOB_POOL_COMPILE analysis)
   set_property(TARGET ${targetExeName} PROPERTY JOB_POOL_LINK analysis)
 
-  if(A_REUSE_FROM)
+  if(A_REUSE_FROM AND NOT DEFINED ENV{USE_RECC})
     target_precompile_headers(${targetExeName} REUSE_FROM ${A_REUSE_FROM})
   endif()