[CMake] CheckTypeSize and non-standard headers

[Aaron Turner]

On Mon, Feb 16, 2009 at 5:53 PM, Michael Jackson
<mike.jackson at bluequartz.net> wrote:
> project(Test)
> cmake_minimum_required(VERSION 2.7)
>
> INCLUDE(${CMAKE_ROOT}/Modules/CheckTypeSize.cmake)
>
> set(CMAKE_REQUIRED_DEFINITIONS_SAVE ${CMAKE_REQUIRED_DEFINITIONS})
> set(CMAKE_REQUIRED_DEFINITIONS
> ${CMAKE_REQUIRED_DEFINITIONS};-D__need_wint_t=1)
>
> CHECK_TYPE_SIZE(wint_t WINT_T)
> message(STATUS "Size of wint_t: ${WINT_T}")
> message(STATUS "HAVE_WINT_T: ${HAVE_WINT_T}")
>
> set(CMAKE_REQUIRED_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS_SAVE})
>
> Although I am not sure under what circumstances you are supposed to define
> __need_wint_t? Or if there is some other encompassing macro to define.
> Otherwise the above will find the size in bytes of wint_t.

Not sure I follow what you're trying to accomplish with the above.
Is this cmake 2.7 specific or some trick with the __need_wint_t (which
isn't used in runetype.h)?

For now, i'm just hacking around the issue with:

check_include_file("runetype.h"     HAVE_RUNETYPE_H)
IF(APPLE AND HAVE_RUNETYPE_H)
    # OS X has wint_t, but check_type_size won't find it
    SET(HAVE_WINT_T 1)
ELSE(APPLE AND HAVE_RUNETYPE_H)
    check_type_size("wint_t"            HAVE_WINT_T)
ENDIF(APPLE AND HAVE_RUNTYPE_H)

Long term, I'm going to write my own version of check_symbol_exists
which uses a different test which is define/typedef agnostic.

-- 
Aaron Turner
http://synfin.net/
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