why built on sco5
Shortly: I always tried to build xemacs without compatibility mode.
That is why I failed and had to patch xemacs as described in
<02343979a3aa08-gin(a)mo.msk.ru> posted to <xemacs-patches(a)xemacs.org>
on Sat, 22 Jul 2000 13:37:46 (GMT). Even if this patch will not be
applied, perhaps it should be mentioned in `PROBLEMS' entry concerning
sco5 that xemacs also may be built with gcc-2.95.2 in native sco5
mode.
(Vanilla) xemacs has (and had at least in 19.12) trouble with
encapsulated `stat' on sco5. `#undef stat' of "sysfile.h" causes type
mismatches between declarations of what should be `struct stat'
residing before redefinition in <sys/stat.h> and after it.
But this happens only if we use new `stat' stuff set using struct
`st_stat32'. When we use old `stat' stuff based on struct
`st_stat16', `stat' is not redefined by system headers and all decls
match.
Stuff based on `st_stat32' is used in all `native' sco programs.
Stuff based on `st_stat16' is used when compiling in mode of
compatibility with pre-v5 sco (v. 4 or xenix). In particular, `cc'
(from sco5 development system) is able (with `-a ods30' option) to
build programs for sco4 which also will run on sco5.
This option may be set in system- wide defaults file, which will cause
xemacs to build without any code changes as described in `PROBLEMS'
file in xemacs distribution.
My (supplied with v. 5.0.2) version of development system does not
have `icc' mentioned in `PROBLEMS'. I suspect, however, that this
compiler is borrowed from older sco systems and works in compatibility
mode by default. Perhaps Robert Lipe will be able to check this
hypothesis.