Use of access(X_OK) check in pg_upgrade

I broke the Win32 build members by using access(X_OK) in pg_upgrade.  I
have a fix for this but looking at pg_upgrade's exec.c, I see for
Win32:
    if ((buf.st_mode & S_IXUSR) == 0)

I am confused why Windows supports S_IXUSR but not X_OK.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + It's impossible for everything to be true. +