include(CheckCXXSourceCompiles)

check_cxx_source_compiles(
	"
	#include <iconv.h>
	// this declaration will fail when there already exists a non const char** version which returns size_t
	double iconv(iconv_t cd,  char **inbuf, size_t *inbytesleft, char **outbuf, size_t *outbytesleft);
	int main() { return 0; }
	"
	HAVE_ICONV_CONST
)