Merge branch 'feature/update-cmake' into 'master'

Cleanup the cmake configuration and add library Dune::Gmsh4

See merge request iwr/dune-gmsh4!15

CMakeLists.txt

@@ -17,12 +17,14 @@ include(DuneMacros)
 
 # start a dune project with information from dune.module
 dune_project()
+dune_add_library(dunegmsh4 
+  EXPORT_NAME Gmsh4
+  LINK_LIBRARIES ${DUNE_LIBS})
 
 add_subdirectory(src)
 add_subdirectory(dune)
 add_subdirectory(doc)
-add_subdirectory(lib)
 add_subdirectory(cmake/modules)
 
 # finalize the dune project, e.g. generating config.h etc.
-finalize_dune_project(GENERATE_CONFIG_H_CMAKE)
+finalize_dune_project()

dune/gmsh4/CMakeLists.txt

-dune_add_library("gmsh4types" OBJECT
+target_sources(dunegmsh4 PRIVATE
   types.cc)
 
 #install headers

dune/gmsh4/utility/CMakeLists.txt

-dune_add_library("filesystem" OBJECT
+target_sources(dunegmsh4 PRIVATE
   filesystem.cc)
 
 #install headers

lib/CMakeLists.txt

-# OBJECT is needed since CMake 3.0.0
-# but it conflicts with shared libs
-set(_OBJECT_FLAG "OBJECT")
-if(BUILD_SHARED_LIBS)
-  set(_OBJECT_FLAG "")
-endif()
-
-dune_add_library(dunegmsh4
-  _DUNE_TARGET_OBJECTS:filesystem_
-  _DUNE_TARGET_OBJECTS:gmsh4types_
-  ADD_LIBS ${DUNE_LIBS})