dir.c: use self-made IFTODT in rb_pathtype_t if available

dir.c defines IFTODT if the system doesn't have it. The macro is used
when comparing with rb_pathtype_t's cases. rb_pathtype_t's cases are
defined by DT_XXX macro if they are available, or defined using IFTODT.
Most POSIX-compatible platforms have both IFTODT and DT_XXX and most of
other platforms like MinGW have neither of them. On those platforms,
DT_XXX-oriented rb_pathtype_t is always compared with values converted
by system's IFTODT, and emulated-IFTODT-oriented rb_pathtype_t is always
compared with values converted by emulated-IFTODT.

However, when IFTODT is *not defined* and DT_XXX is *defined*, like
on wasi-libc, DT_XXX-oriented rb_pathtype_t was compared with values
converted by emulated-IFTODT, and they are not guaranteed to be
compatible.

This patch fixes such a situation by using emulated-IFTODT to define
rb_pathtype_t when either IFTODT or DT_XXX is not available.

0 files changed, 0 insertions, 0 deletions