cc -pthread  -Wall -Wextra -Werror=implicit-function-declaration sys_mman/posix_madvise.c -o sys_mman/posix_madvise -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE -lm -lpthread -lrt -lintl -liconv
sys_mman/posix_madvise.c: In function ‘main’:
sys_mman/posix_madvise.c:17:14: error: implicit declaration of function ‘posix_madvise’ [-Wimplicit-function-declaration]
   17 |         if ( posix_madvise(page, pagesize, POSIX_MADV_SEQUENTIAL) < 0 )
      |              ^~~~~~~~~~~~~
sys_mman/posix_madvise.c:17:44: error: ‘POSIX_MADV_SEQUENTIAL’ undeclared (first use in this function)
   17 |         if ( posix_madvise(page, pagesize, POSIX_MADV_SEQUENTIAL) < 0 )
      |                                            ^~~~~~~~~~~~~~~~~~~~~
sys_mman/posix_madvise.c:17:44: note: each undeclared identifier is reported only once for each function it appears in