13 Jul
2018
13 Jul
'18
11:32 a.m.
Gentlepeople,
Once in a while people ask about GCC. It has long had pdp11 support, but it hasn't
received much attention. Recently I've done some cleanup on it, and some more is in
the pipeline.
One notable new feature is that it can now produce proper DEC Macro-11 syntax output. It
has long had a -mdec-asm switch, but that used to produce GNU output. Now it produces DEC
output (and -mgnu-asm is how you get output for "gas".)
The optimizer is better, and a bunch of compiler failures are fixed. Undoubtedly there
are more bugs to be worked on.
Oh yes, for grins I told GCC to build not just a C compiler but a C++ and Fortran compiler
as well. That seems to work (but I get an error building the libstdc++ library). I now
have C++ translations of the RSTS standard header files common.mac and kernel.mac, and the
DECnet definitions in netdef.sml. :-)
If anyone wants to give this a try, the best way is to get the current code via Subversion
(see gcc.gnu.org for details). Alternatively, get a weekly snapshot; the DEC support is
in the current latest, though some optimizer work will appear in the next one.
paul
13 Jul
13 Jul
1:12 p.m.
Great news, Paul!
I'll try and give this a go this weekend.
Aaron
Paul Koning via cctalk writes:
Gentlepeople,
Once in a while people ask about GCC. It has long had pdp11 support,
but it hasn't received much attention. Recently I've done some
cleanup on it, and some more is in the pipeline.
One notable new feature is that it can now produce proper DEC Macro-11
syntax output. It has long had a -mdec-asm switch, but that used to
produce GNU output. Now it produces DEC output (and -mgnu-asm is how
you get output for "gas".)
The optimizer is better, and a bunch of compiler failures are fixed.
Undoubtedly there are more bugs to be worked on.
Oh yes, for grins I told GCC to build not just a C compiler but a C++
and Fortran compiler as well. That seems to work (but I get an error
building the libstdc++ library). I now have C++ translations of the
RSTS standard header files common.mac and kernel.mac, and the DECnet
definitions in netdef.sml. :-)
If anyone wants to give this a try, the best way is to get the current
code via Subversion (see gcc.gnu.org for details). Alternatively, get
a weekly snapshot; the DEC support is in the current latest, though
some optimizer work will appear in the next one.
paul
--
Aaron Jackson
PhD Student, Computer Vision Laboratory, Uni of Nottingham
http://aaronsplace.co.uk
5:12 p.m.
On 07/13/2018 02:32 PM, Paul Koning via cctalk wrote:
Gentlepeople,
Once in a while people ask about GCC. It has long had pdp11 support, but it hasn't
received much attention. Recently I've done some cleanup on it, and some more is in
the pipeline.
One notable new feature is that it can now produce proper DEC Macro-11 syntax output. It
has long had a -mdec-asm switch, but that used to produce GNU output. Now it produces DEC
output (and -mgnu-asm is how you get output for "gas".)
The optimizer is better, and a bunch of compiler failures are fixed. Undoubtedly there
are more bugs to be worked on.
Oh yes, for grins I told GCC to build not just a C compiler but a C++ and Fortran
compiler as well. That seems to work (but I get an error building the libstdc++ library).
I now have C++ translations of the RSTS standard header files common.mac and kernel.mac,
and the DECnet definitions in netdef.sml. :-)
If anyone wants to give this a try, the best way is to get the current code via
Subversion (see gcc.gnu.org for details). Alternatively, get a weekly snapshot; the DEC
support is in the current latest, though some optimizer work will appear in the next one.
I am going to have to take a look at this.? I have been meaning
to dig out a really old version of GCC because I thought they
removed all the PDP-11 stuff ages ago.? This could be fun again.
bill
5:18 p.m.
On Fri, Jul 13, 2018 at 6:12 PM, Bill Gunshannon via cctalk <
cctalk at classiccmp.org> wrote:
On 07/13/2018 02:32 PM, Paul Koning via cctalk wrote:
I am going to have to take a look at this. I have been meaning
to dig out a really old version of GCC because I thought they
removed all the PDP-11 stuff ages ago. This could be fun again.
Can it build interesting things like V7 and/or 2BSD?
Warner
Gentlepeople,
Once in a while people ask about GCC. It has long had pdp11 support,
but it
hasn't received much attention. Recently I've done some cleanup on
it, and some more is in the pipeline.
One notable new feature is that it can now produce proper DEC Macro-11
syntax
output. It has long had a -mdec-asm switch, but that used to
produce GNU output. Now it produces DEC output (and -mgnu-asm is how you
get output for "gas".)
The optimizer is better, and a bunch of compiler failures are fixed.
Undoubtedly
there are more bugs to be worked on.
Oh yes, for grins I told GCC to build not just a C compiler but a C++
and Fortran
compiler as well. That seems to work (but I get an error
building the libstdc++ library). I now have C++ translations of the RSTS
standard header files common.mac and kernel.mac, and the DECnet definitions
in netdef.sml. :-)
If anyone wants to give this a try, the best way is to get the current
code via
Subversion (see gcc.gnu.org for details). Alternatively, get a
weekly snapshot; the DEC support is in the current latest, though some
optimizer work will appear in the next one.
6:04 p.m.
On Jul 13, 2018, at 8:18 PM, Warner Losh via cctalk
<cctalk at classiccmp.org> wrote:
On Fri, Jul 13, 2018 at 6:12 PM, Bill Gunshannon via cctalk <
cctalk at classiccmp.org> wrote:
I don't know; I have not tried that.
One point that may be relevant. GCC typically supports several variants for any given
target processor, for different operating systems or the like. And the pdp11 target at
one point had a 2bsd variant. That one was indeed removed some years ago. I haven't
yet tried to bring it back, partly due to lack of experience with 2BSD. But I'm
thinking about it.
My expectation is that the code would compile fine, but possibly might not link or produce
a valid binary if there are ABI differences or library mismatches. Input from those who
know this stuff better would be helpful. Note that contributions are welcome; there
hasn't been much in recent years but there has been a bit occasionally, and I
certainly would appreciate that.
Finally, if you spot bugs, the GCC Bugzilla machinery would probably be the best way to
report them, though you can email me if you want for an initial check.
paul
On 07/13/2018 02:32 PM, Paul Koning via cctalk wrote:
I am going to have to take a look at this. I have been meaning
to dig out a really old version of GCC because I thought they
removed all the PDP-11 stuff ages ago. This could be fun again.
Can it build interesting things like V7 and/or 2BSD?
Warner Gentlepeople,
Once in a while people ask about GCC. It has long had pdp11 support,
but it
hasn't received much attention. Recently I've done some cleanup on
it, and some more is in the pipeline.
One notable new feature is that it can now produce proper DEC Macro-11
syntax
output. It has long had a -mdec-asm switch, but that used to
produce GNU output. Now it produces DEC output (and -mgnu-asm is how you
get output for "gas".)
The optimizer is better, and a bunch of compiler failures are fixed.
Undoubtedly
there are more bugs to be worked on.
Oh yes, for grins I told GCC to build not just a C compiler but a C++
and Fortran
compiler as well. That seems to work (but I get an error
building the libstdc++ library). I now have C++ translations of the RSTS
standard header files common.mac and kernel.mac, and the DECnet definitions
in netdef.sml. :-)
If anyone wants to give this a try, the best way is to get the current
code via
Subversion (see gcc.gnu.org for details). Alternatively, get a
weekly snapshot; the DEC support is in the current latest, though some
optimizer work will appear in the next one.
14 Jul
14 Jul
6:46 a.m.
Hey, glad to hear of some improvement on GCC for the PDP-11.? Last
spring I ended up side-tracked on the QSIC project and working more on
FPGA issues than writing PDP-11 code but that's going to change here at
some point.? I still want to put a soft PDP-11 into the FPGA as an I/O
controller and will need to be writing code for it.
For the moment, I'm off at my summer job in Alaska but when I get home
this fall, it's back to working away on the QSIC and maybe my PDP-10
project where I'm thinking I may also use a soft PDP-11 as an I/O
processor.? Anyway, I'll grab up the new GCC and see if my issues with
the 'volatile' keyword are still there.
Dave
10:51 a.m.
On Jul 14, 2018, at 9:46 AM, David Bridgham via cctalk
<cctalk at classiccmp.org> wrote:
Hey, glad to hear of some improvement on GCC for the PDP-11. Last
spring I ended up side-tracked on the QSIC project and working more on
FPGA issues than writing PDP-11 code but that's going to change here at
some point. I still want to put a soft PDP-11 into the FPGA as an I/O
controller and will need to be writing code for it.
For the moment, I'm off at my summer job in Alaska but when I get home
this fall, it's back to working away on the QSIC and maybe my PDP-10
project where I'm thinking I may also use a soft PDP-11 as an I/O
processor. Anyway, I'll grab up the new GCC and see if my issues with
the 'volatile' keyword are still there.
I didn't directly address anything like that, but it may well be that things are
better. "Volatile" is a very tricky area. There is detailed discussion in the
GCC manual about when volatile objects are accessed. You may want to review that.
Sometimes the rules are not precisely what you might expect.
paul
10 Dec
10 Dec
1:28 p.m.
Hello Paul!
When I read this once upon during the summer I saw that the problems I once
had reported was solved and it was great news. Really thankful that you did
so much work with this!
However I know tried to turn on optimizations and then it fails in a
strange way.
If you have some spare time maybe you could check why it fails on when
11/10 but not when set to 11/40. And it only fails for even powers of two
above 16. It is the if that fails so if I remove that one it works.
The bug report is https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88435
/Mattis
Den l?r 14 juli 2018 kl 19:51 skrev Paul Koning via cctalk <
cctalk at classiccmp.org>:
On Jul 14, 2018, at 9:46 AM, David Bridgham via
cctalk <
cctalk at classiccmp.org> wrote:
Hey, glad to hear of some improvement on GCC for the PDP-11. Last
spring I ended up side-tracked on the QSIC project and working more on
FPGA issues than writing PDP-11 code but that's going to change here at
some point. I still want to put a soft PDP-11 into the FPGA as an I/O
controller and will need to be writing code for it.
For the moment, I'm off at my summer job in Alaska but when I get home
this fall, it's back to working away on the QSIC and maybe my PDP-10
project where I'm thinking I may also use a soft PDP-11 as an I/O
processor. Anyway, I'll grab up the new GCC and see if my issues with
the 'volatile' keyword are still there.
I didn't directly address anything like that, but it may well be that
things are better. "Volatile" is a very tricky area. There is detailed
discussion in the GCC manual about when volatile objects are accessed. You
may want to review that. Sometimes the rules are not precisely what you
might expect.
paul
1964
days inactive
2114
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7 comments
6 participants
participants (6)
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aaron＠aaronsplace.co.uk -
bill.gunshannon＠hotmail.com -
dab＠froghouse.org -
imp＠bsdimp.com -
mattislind＠gmail.com -
paulkoning＠comcast.net