DGUX Unix - GCC-2.95.x

[Takis Psarogiannakopoulos <takis at XFree86 dot org>]

Dear Folks,
I write this e-mail in the list since I tried to
contact some folks in Cygnus with no luck.
In the release gcc-2.8.1 several developers fix the support
for the DG/ux unix (i386). gcc-2.8.1 was officially
the first gcc with good support for ix86 DG/ux.
Then the egcs project took over gcc, so 2.8.1 was the last
(actual) GNU release.
gcc-2.95 broke totally all the support for DG/ux. While
I understand that you may not have access to a DG/ux machine
, I write this e-mail because , besides the compilation
errors, you change and the behaviour of cpp.
Until the gcc-2.8.1, cpp was a binary in the gcc-local-dir
(usually: /usr/local/lib/gcc-lib/host/2.95 or 2.8.1) and not in
/usr/local/bin. Nothing however stopping us to copy this
single binary to the path. DG/ux unix has a special complicated
"elink" mechanism that finally it will divert the  /lib/cpp
classical Unix preprocessor to ->gcc-local-dir/cpp.
This will be also the cpp for the "cc" of the system (than
amongst others builds the kernels of the system).
However in 2.95 you split cpp to xcpp (gcc.o + some other
 .o files ,) and the actuall cpp in the gcc-local-dir , only
that this second cpp lacks functionality over the previous
such (eg 2.8.1). Eg doesnt know cpp_predefines , -undef option
etc. This results in that cc breaks and anything that uses cc also
(eg the imake command in XFree86) including building correctly the
(DGUX) kernels of the system.
I took the time these days to make the port of 2.95 to ix86 DG/ux
only to discover that it is impossible to run it to DG/ux. The option
of copying the external cpp (xcpp) to the gcc-local-dir is out
since gcc-local-dir has the actuall cpp which will be overwritten. Also
naming the xcpp something else means that we are looking to modify
then the elink (OS) mechanism of DG/ux to look for this thing.
If you found that the cpp should separate in two modules the correct
thing to do will be to name the "internal" cpp in the gcc-local-dir
as , say , int_cpp , have gcc and cpp to invoke this binary (so that
xcpp=cpp and int_cpp can coexist in the same dir) and have also the xcpp
understand _ALL_ the commands that the gcc-2.8.1 cpp knew!
At the moment gcc-2.95 is not even installable in ix86 DG/ux. If that
was what we do in XFree86 only Linux and FreeBSD will now had Xwindows!
Even if we dont have a DG/ux machine we never do  such a change,
given that in the 2.8.1 was a binary "cpp" that was performing some
functionality. So somebody maybe was using this binary for other
functionalities (eg ix86 DG/ux). Just eliminating its features in the next
release and test it in Linux is not , in my opinion , development of
gcc , not at least the one that GNU was pursuing all these years.
Please correct this situation and restore cpp in its full features
as in 2.8.1. If you feel that an internal module is needed, name it
something else (eg int_cpp or whatever) so that can coexist in the
gcc-local-dir with the binary of cpp and arrange for cpp gcc to use
it accordingly.

Regards,
T.