Merge branch 'CppStandardSet-23.0-20230710' into '23.0'

C++ Standard Setting, 23.0 branch (2023.07.10.)

See merge request atlas/athena!64242

Projects/AnalysisBase/cmake/PreConfig.cmake.in

@@ -4,6 +4,12 @@
 # @CMAKE_PROJECT_NAME@.
 #
 
+# Set the C++ standard to use.
+set( CMAKE_CXX_STANDARD "@CMAKE_CXX_STANDARD@"
+   CACHE STRING "C++ standard used for the build" )
+set( CMAKE_CXX_EXTENSIONS "@CMAKE_CXX_EXTENSIONS@"
+   CACHE STRING "(Dis)Allow the usage of C++ extensions" )
+
 # Use the -pthread flag for the build instead of the -lpthread linker option,
 # if the main project was set up in that way.
 set( THREADS_PREFER_PTHREAD_FLAG @THREADS_PREFER_PTHREAD_FLAG@ CACHE BOOL

Projects/AthAnalysis/cmake/PreConfig.cmake.in

@@ -3,6 +3,12 @@
 # Pre-config script to propagate variables to downstream projects
 #
 
+# Set the C++ standard to use.
+set( CMAKE_CXX_STANDARD "@CMAKE_CXX_STANDARD@"
+   CACHE STRING "C++ standard used for the build" )
+set( CMAKE_CXX_EXTENSIONS "@CMAKE_CXX_EXTENSIONS@"
+   CACHE STRING "(Dis)Allow the usage of C++ extensions" )
+
 # HepMC3
 set( HEPMC3_USE @HEPMC3_USE@ CACHE BOOL "Use HepMC3 in the project" )
 

Projects/AthDataQuality/cmake/PreConfig.cmake.in

-# Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
+# Copyright (C) 2002-2023 CERN for the benefit of the ATLAS collaboration
 #
 # File taking care of pointing the downstream projects at the right
 # version of LCG.
 #
 
+# Set the C++ standard to use.
+set( CMAKE_CXX_STANDARD "@CMAKE_CXX_STANDARD@"
+   CACHE STRING "C++ standard used for the build" )
+set( CMAKE_CXX_EXTENSIONS "@CMAKE_CXX_EXTENSIONS@"
+   CACHE STRING "(Dis)Allow the usage of C++ extensions" )
+
 # HepMC3
 set( HEPMC3_USE @HEPMC3_USE@ CACHE BOOL "Use HepMC3 in the project" )
 

Projects/AthDerivation/cmake/PreConfig.cmake.in

-# Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
+# Copyright (C) 2002-2023 CERN for the benefit of the ATLAS collaboration
 #
 # Pre-config script to propagate variables to downstream projects
 #
 
+# Set the C++ standard to use.
+set( CMAKE_CXX_STANDARD "@CMAKE_CXX_STANDARD@"
+   CACHE STRING "C++ standard used for the build" )
+set( CMAKE_CXX_EXTENSIONS "@CMAKE_CXX_EXTENSIONS@"
+   CACHE STRING "(Dis)Allow the usage of C++ extensions" )
+
 # HepMC3
 set( HEPMC3_USE @HEPMC3_USE@ CACHE BOOL "Use HepMC3 in the project" )
 

Projects/AthGeneration/cmake/PreConfig.cmake.in

-# Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
+# Copyright (C) 2002-2023 CERN for the benefit of the ATLAS collaboration
 #
 # Pre-config script to propagate variables to downstream projects
 #
 
+# Set the C++ standard to use.
+set( CMAKE_CXX_STANDARD "@CMAKE_CXX_STANDARD@"
+   CACHE STRING "C++ standard used for the build" )
+set( CMAKE_CXX_EXTENSIONS "@CMAKE_CXX_EXTENSIONS@"
+   CACHE STRING "(Dis)Allow the usage of C++ extensions" )
+
 # HepMC3
 set( HEPMC3_USE @HEPMC3_USE@ CACHE BOOL "Use HepMC3 in the project" )
 

Projects/AthSimulation/cmake/PreConfig.cmake.in

-# Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
+# Copyright (C) 2002-2023 CERN for the benefit of the ATLAS collaboration
 #
 # Pre-config script to propagate variables to downstream projects
 #
 
+# Set the C++ standard to use.
+set( CMAKE_CXX_STANDARD "@CMAKE_CXX_STANDARD@"
+   CACHE STRING "C++ standard used for the build" )
+set( CMAKE_CXX_EXTENSIONS "@CMAKE_CXX_EXTENSIONS@"
+   CACHE STRING "(Dis)Allow the usage of C++ extensions" )
+
 # HepMC3
 set( HEPMC3_USE @HEPMC3_USE@ CACHE BOOL "Use HepMC3 in the project" )
 

Projects/Athena/cmake/PreConfig.cmake.in

-# Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
+# Copyright (C) 2002-2023 CERN for the benefit of the ATLAS collaboration
 #
 # Pre-config script to propagate variables to downstream projects
 #
 
+# Set the C++ standard to use.
+set( CMAKE_CXX_STANDARD "@CMAKE_CXX_STANDARD@"
+   CACHE STRING "C++ standard used for the build" )
+set( CMAKE_CXX_EXTENSIONS "@CMAKE_CXX_EXTENSIONS@"
+   CACHE STRING "(Dis)Allow the usage of C++ extensions" )
+
 # HepMC3
 set( HEPMC3_USE @HEPMC3_USE@ CACHE BOOL "Use HepMC3 in the project" )
 

Projects/DetCommon/cmake/PreConfig.cmake.in

-# Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
+# Copyright (C) 2002-2023 CERN for the benefit of the ATLAS collaboration
 #
 # File taking care of pointing the downstream projects at the right
 # version of LCG.
 #
 
+# Set the C++ standard to use.
+set( CMAKE_CXX_STANDARD "@CMAKE_CXX_STANDARD@"
+   CACHE STRING "C++ standard used for the build" )
+set( CMAKE_CXX_EXTENSIONS "@CMAKE_CXX_EXTENSIONS@"
+   CACHE STRING "(Dis)Allow the usage of C++ extensions" )
+
 # Use the -pthread flag for the build instead of the -lpthread linker option,
 # if the main project was set up in that way.
 set( THREADS_PREFER_PTHREAD_FLAG @THREADS_PREFER_PTHREAD_FLAG@ CACHE BOOL