[CMake] static library from several subdirectories

[Verweij, Arjen]

Hi,

>From: Michael Wild [mailto:themiwi at gmail.com]

>I'd recommend to change the add_sources function to do all the
>preprocessing and then only add the products (.f, .f90, .c etc.) files
>to the list. You can do the preprocessing like this (of course, you'll
>have to change things for your setup, perhaps even do different things
>depending on filename extension etc.)
>
>find_program(FPP_EXECUTABLE fpp)
>if(NOT FPP_EXECUTABLE)
>  message(SEND_ERROR "Failed to find fpp")
>endif()
>
>set(SRCS)
>foreach(src IN LISTS ARGN)
>  get_filename_component(abs_src "${src}" ABSOLUTE)
>  file(RELATIVE_PATH rel_src "${CMAKE_CURRENT_SOURCE_DIR}" "${abs_src}")
>  set(pre "${CMAKE_CURRENT_BINARY_DIR}/${rel_src}")
>  add_custom_command(OUTPUT "${pre}"
>    COMMAND ${FPP_EXECUTABLE} "${abs_src}" -o "${pre}"
>    WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}"
>    COMMENT "Creating ${pre}"
>    VERBATIM
>    )
>  list(APPEND SRCS "${pre}")
>endforeach()
>set_property(GLOBAL APPEND PROPERTY "${target}_SRCS" "${SRCS}")

The flow currently is:
# build mybiglib.a

- loop over a file list retrieved from a leaf cmake file
- determine the file type (FORTRAN FORTRAN90 C C++ header file etc etc)
- add_custom_command that creates a DEPENDS of the required OUTPUT source file based on its source*r file based on a COMMAND.
- add the OUTPUT to a filelist_m or filelist_h if is is a header file
- setup a FORTRAN module directory in ${CMAKE_BINARY_DIR}
- add a dependency between the header files and the current dir for preprocessing
- ADD_SOURCES( ${BIG_LIB} ${filelist_m} ) # Michael's code
- process some out of tree include directories # this requires touching up, but seems to work in the old setup
- add them as a dependency for biglib
- add a dependency between biglib and the current dir preprocessing target
- call include_directories() for every out of tree include directory

The calls that are failing are:
-     add_dependencies (${BIG_LIB} ${P1TARGET}_preprocessing) (2x)
-     add_dependencies (${BIG_LIB} ${CUR_DIR}_preprocessing)

The context is:

    # use one mod dir per CMAKE_BINARY_DIR instead of a single mod dir per CMAKE_CURRENT_BINARY_DIR
    # FIXME there may be a problem with duplicate names for the modules -- check with development
    set (CMAKE_Fortran_MODULE_DIRECTORY "${CMAKE_BINARY_DIR}/mod")
    add_custom_target (${CUR_DIR}_preprocessing DEPENDS ${FILE_LIST_H})
    ADD_SOURCES( ${BIG_LIB} ${FILE_LIST_M} )
    message ( STATUS filelist_m=${FILE_LIST_M} )
    # refactor later
    foreach (IDIR ${INCLUDE_DIRECTORIES_PREPRO})
    include_directories (${CMAKE_BINARY_DIR}/${IDIR})
    string (REPLACE / _ PTARGET ${IDIR})
    string (REGEX REPLACE "^(.+)_$" "\\1" P1TARGET ${PTARGET})

    add_dependencies (${BIG_LIB} ${P1TARGET}_preprocessing) #fails now
    endforeach (IDIR)
    add_dependencies (${BIG_LIB} ${CUR_DIR}_preprocessing) #fails now

    foreach (IDIR ${INCLUDE_DIRECTORIES})
    include_directories (${IDIR})
    endforeach (IDIR)


I'll be looking into this some more at the end of the day.

Regards,
Arjen