#if defined(__linux__) || defined(__GLIBC__)
# include <features.h>
# if (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 1 || __GLIBC__ > 2) \
#if defined(__linux__) || defined(__GLIBC__)
# include <features.h>
# if (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 1 || __GLIBC__ > 2) \