Import patches for building single Geant4 library

From Caterina Marcon's work at:

https://gitlab.cern.ch/cmarcon/geant4-singledynamiclibrary/-/commit/11282afc33b536305ba2d45d899f27c3f64a6f9e

cmake/Modules/G4BuildSettings.cmake

@@ -340,15 +340,20 @@ endif()
 # both types. If neither is selected, an error is emitted.
 #
 option(BUILD_SHARED_LIBS "Build Geant4 shared libraries" ON)
+option(BUILD_SHARED_SINGLE_LIB "Build Geant4 into a single dynamic library" OFF) #CM
 option(BUILD_STATIC_LIBS "Build Geant4 static libraries" OFF)
-mark_as_advanced(BUILD_SHARED_LIBS BUILD_STATIC_LIBS)
+mark_as_advanced(BUILD_SHARED_LIBS BUILD_SHARED_SINGLE_LIB BUILD_STATIC_LIBS) #CM
 
 # Because both could be switched off accidently, FATAL_ERROR if neither
 # option has been selected.
-if(NOT BUILD_STATIC_LIBS AND NOT BUILD_SHARED_LIBS)
+if(NOT BUILD_STATIC_LIBS AND NOT BUILD_SHARED_LIBS AND NOT BUILD_SHARED_SINGLE_LIB) #CM
   message(FATAL_ERROR "Neither static nor shared libraries will be built")
 endif()
 
+if(BUILD_SHARED_SINGLE_LIB) #CM
+  set(BUILD_SHARED_LIBS ON)
+endif()
+
 # Always build global libraries - always FATAL_ERROR if old
 # granular library switch is set, e.g. from command line
 if(GEANT4_BUILD_GRANULAR_LIBS)

cmake/Modules/G4CMakeMain.cmake

@@ -88,6 +88,8 @@ if(GEANT4_USE_PYTHON)
   add_subdirectory(environments/g4py)
 endif()
 
+include(G4SingleLibrary)
+
 #-----------------------------------------------------------------------
 # - Perform all post build tasks
 # At the CMake level, this simply means that we must know about targets

cmake/Modules/G4DeveloperAPI_OLD.cmake

@@ -230,10 +230,18 @@ macro(geant4_library_target)
     "NAME" "SOURCES;GEANT4_LINK_LIBRARIES;LINK_LIBRARIES"
     ${ARGN}
     )
+  if(BUILD_SHARED_SINGLE_LIB AND BUILD_SHARED_LIBS)
+    set_property(GLOBAL APPEND PROPERTY ALL_LIBS_NAME "${G4LIBTARGET_NAME}")
+    set_property(GLOBAL APPEND PROPERTY ALL_LIBS_OBJ "$<TARGET_OBJECTS:${G4LIBTARGET_NAME}>")
+    set_property(GLOBAL APPEND PROPERTY ALL_LIBS_GEANT4_LINK_LIBRARIES "${G4LIBTARGET_GEANT4_LINK_LIBRARIES} ")
+    set_property(GLOBAL APPEND PROPERTY ALL_LIBS_LINK_LIBRARIES "${G4LIBTARGET_LINK_LIBRARIES} ")
+    add_library(${G4LIBTARGET_NAME} OBJECT ${G4LIBTARGET_SOURCES})
+    #target_compile_definitions(${G4LIBTARGET_NAME} PUBLIC ${G4LIBTARGET_NAME})
+  endif()
 
   geant4_format_target(NAME ${G4LIBTARGET_NAME}-format SOURCES ${G4LIBTARGET_SOURCES})
 
-  if(BUILD_SHARED_LIBS)
+  if(BUILD_SHARED_LIBS AND NOT BUILD_SHARED_SINGLE_LIB)
     # Add the shared library target and link its dependencies
     # - Common shared lib commands
     add_library(${G4LIBTARGET_NAME} SHARED ${G4LIBTARGET_SOURCES})

cmake/Modules/G4SingleLibrary.cmake

+# - Include guard
+if(NOT __G4SINGLE_LIBRARY_INCLUDED)
+  set(__G4SINGLE_LIBRARY_INCLUDED 1)
+else()
+  return()
+endif()
+
+if (BUILD_SHARED_SINGLE_LIB)
+
+    message(STATUS "===========================================================================")
+    message(STATUS "Starting SingleLibrary section")
+
+    get_property(__geant4_all_libs_name GLOBAL PROPERTY ALL_LIBS_NAME)
+    get_property(__geant4_all_libs_obj GLOBAL PROPERTY ALL_LIBS_OBJ)
+    get_property(__geant4_all_libs_g4_link_libs GLOBAL PROPERTY ALL_LIBS_GEANT4_LINK_LIBRARIES)
+    get_property(__geant4_all_libs_link_libs GLOBAL PROPERTY ALL_LIBS_LINK_LIBRARIES)
+
+
+    message(STATUS ${__geant4_all_libs_obj})
+    add_library(single_dynamic SHARED ${__geant4_all_libs_obj})
+
+
+    geant4_compile_definitions_config(single_dynamic)
+    target_compile_features(single_dynamic PUBLIC ${GEANT4_TARGET_COMPILE_FEATURES})
+#    target_link_libraries(single_dynamic PUBLIC ${__geant4_all_libs_name})
+#    target_link_libraries(single_dynamic ${__geant4_all_libs_link_libs})
+#                          ${__geant4_all_libs_g4_link_libs}
+#                          ${__geant4_all_libs_link_libs})
+    message(STATUS "===========================================================================")
+    message(STATUS ${__geant4_all_libs_link_libs})
+    message(STATUS "===========================================================================")
+    message(STATUS ${__geant4_all_libs_g4_link_libs})
+    target_link_libraries(single_dynamic /usr/lib64/libfreetype.so
+                          /data/cmarcon/Libraries/libexpat/install/lib64/libexpat.so
+                          /usr/lib64/libXm.so
+                          /usr/lib64/libSM.so
+                          /usr/lib64/libICE.so
+                          /usr/lib64/libX11.so
+                          /usr/lib64/libXext.so
+                          /usr/lib64/libXt.so
+                          /usr/lib64/libXmu.so
+                          /data/cmarcon/Libraries/libxerces/install/lib/libxerces-c.so
+                          /usr/lib64/libGL.so
+                          /usr/lib64/libGLU.so)
+    target_compile_definitions(single_dynamic PUBLIC G4LIB_BUILD_DLL)
+    set_target_properties(single_dynamic PROPERTIES WINDOWS_EXPORT_ALL_SYMBOLS ON)
+    set_target_properties(single_dynamic PROPERTIES CLEAN_DIRECT_OUTPUT 1)
+    set_target_properties(single_dynamic PROPERTIES MACOSX_RPATH 1)
+
+    install(TARGETS single_dynamic
+            EXPORT Geant4LibraryDepends
+            RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR} COMPONENT Runtime
+            LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR} COMPONENT Runtime
+            ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR} COMPONENT Development)
+
+    set_property(GLOBAL APPEND PROPERTY GEANT4_EXPORTED_TARGETS single_dynamic)
+    set_property(TARGET single_dynamic PROPERTY POSITION_INDEPENDENT_CODE ON)
+
+    message(STATUS "End of SingleLibrary section")
+    message(STATUS "===========================================================================")
+endif()