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&gt; posted to <xemacs-patches(a)xemacs.org&gt; 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.