cc -pthread   -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations sys_mman/POSIX_MADV_SEQUENTIAL.c -o sys_mman/POSIX_MADV_SEQUENTIAL -D_POSIX_C_SOURCE=202405L -lm -lpthread -lrt  -lintl -liconv
sys_mman/POSIX_MADV_SEQUENTIAL.c:3:17: error: ‘POSIX_MADV_SEQUENTIAL’ undeclared here (not in a function)
    3 | int const foo = POSIX_MADV_SEQUENTIAL;
      |                 ^~~~~~~~~~~~~~~~~~~~~