ARM glibc's __aeabi_localeconv does:

struct lconv *
__aeabi_localeconv (void)
{
  return __localeconv ();
}

However, glibc orders the C99 fields in struct lconv thus:

  char int_p_cs_precedes;
  char int_p_sep_by_space;
  char int_n_cs_precedes;
  char int_n_sep_by_space;
  char int_p_sign_posn;
  char int_n_sign_posn;

but the __aeabi_lconv structure (defined in CLIBABI, ARM IHI 0039) has them ordered thus:

  char int_p_cs_precedes;
  char int_n_cs_precedes;
  char int_p_sep_by_space;
  char int_n_sep_by_space;
  char int_p_sign_posn;
  char int_n_sign_posn;

and so a conversion layer is needed to swap int_p_sep_by_space and int_n_cs_precedes.