[bugfix][GridSelector] Write ALUGrid grid defs to separate file to avoid dependencies

of the library to all headers (cmake problem). For all other downstream
modules the grid selection is still written to config.h

CMakeLists.txt

@@ -5,6 +5,9 @@ project("dune-alugrid" C CXX)
 set(BUILD_DOCS 1)
 set(DUNE_REENABLE_ADD_TEST TRUE)
 
+# grid selector in separate file to avoid excessive dependencies
+set(ALUGRID_EXTRA_GRIDSELECTOR_FILE TRUE)
+
 # general stuff
 cmake_minimum_required(VERSION 2.8.12)
 

cmake/modules/DuneAlugridMacros.cmake

@@ -9,9 +9,15 @@ dune_define_gridtype(GRIDSELECTOR_GRIDS GRIDTYPE ALUGRID_SIMPLEX
     DUNETYPE "Dune::ALUGrid< dimgrid, dimworld, simplex, nonconforming >"
     HEADERS dune/alugrid/grid.hh dune/alugrid/dgf.hh)
 
-#if (ENABLE_GRID_SELECTOR)
+# for ALUGrid module we write a separate grid selector file to avoid
+# dependencies of the library files to all headers, for all other module
+# the grid selection defs are written to config.h
+if(DUNE_GRID_GRIDTYPE_SELECTOR AND ALUGRID_EXTRA_GRIDSELECTOR_FILE)
+  file(WRITE "${CMAKE_BINARY_DIR}/gridselector.hh" "#include <config.h>\n${GRIDSELECTOR_GRIDS}")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -include${CMAKE_BINARY_DIR}/gridselector.hh")
+else()
   set(ALUGRID_CONFIG_H_BOTTOM "${ALUGRID_CONFIG_H_BOTTOM} ${GRIDSELECTOR_GRIDS}")
-#endif (ENABLE_GRID_SELECTOR)
+endif()
 
 # avoid conflicts with normal ALUGrid
 if( ALUGRID_CPPFLAGS )