This repository has as its base the latest pclu release fetched from ftp://ftp.lcs.mit.edu/pub/pclu/CLU/DEBIAN/pclu-debian.tar.gz
It didn't work b/c of what looks like a last minute 32/64-bit mixup.
I fixed it and cleaned it up to use C99, both in the "asm" C sources and in the compiler output. I took the liberty of reformatting the "asm" C sources to use a more contemporary style. Since the upstream will probably never release any updates this should not be a problem I hope and it hopefully makes life quite a bit easier for people used to more modern C.
This is still a work in progress, but in the current state it should have a good chance of working on any Unix where Boehm GC works.
pclu came with its own copy of Boehm GC sources. It was stock gc-7.2f
with two trivial wrappers added, clu_alloc_atomic() and clu_alloc().
These two wrappers are now moved to code/sysasm/Opt/alloc.c and we can
remove all gc includes from pclu_sys.h.
Unfortunately some C code still does peek into the gc internals so a public installation of gc cannot be used.
Get a copy of gc-7.2f and configure it with something like:
./configure \
--enable-static=yes --enable-shared=no \
--enable-threads=no --with-libatomic-ops=no \
--prefix=$CLUHOME/code/gc
Build it. Making and running gctest is a good idea if you are on
something non-mainstream. Run make install to get the headers in
code/gc/include the libraries in code/gc/lib (and some docs in
code/gc/share/gc).
Since the code needs private headers you then need to either create a
symlink code/gc/include/private that points to gc-7.2f/include/private
or create that directory and copy over the headers.
To avoid touching -I flags in the makefiles, at least for the initial
attempts, it might be handy to create a symlink:
cd code/include && ln -s ../gc/include/gc
and, similarly, for the library:
cd code && ln -s gc/lib/libgc.a
To be able to run the compiler out of the workspace you will need some symlinks in place. I don't want to commit them, at least not yet, so I've added top-level "symlinks" target. Run
make symlinks
once after checkout to set things up. Among other things it takes care of the symlinks for gc mentioned above.
Check howto.install but bear in mind that some things might be out of
date or not work. Makefiles need more updates and clean ups. Here's
what I do for now:
export CLUHOME=$PWD
# build the libpclu_opt.a library
cd $CLUHOME/code
make -w OPT_FLAGS='-g -O0 -Wall -Wextra'
# build the compiler from the pre-generated sources
cd $CLUHOME/code/cmp
make -w OPT_FLAGS='-g -O0 -Wall -Wextra'
# dump clu libraries: lowlev.lib misc.lib useful.lib
# (think precompiled headers)
cd $CLUHOME/lib
make libs
# rebuild the compiler
cd $CLUHOME/cmpclu
make lib # dump cmp.lib for the compiler sources
make -w OPT_FLAGS='-g -O0 -Wall -Wextra'
# rebuild the compiler again
make -w OPT_FLAGS='-g -O0 -Wall -Wextra'
# verify the output is the same (or, if you changed the compiler,
# check the effect of your change)
cd $CLUHOME/code/cmp
hg diff .
Clu debugger is in-process and is compiled and linked directly into
the program. It should now be in the state where it compiles, and the
debug version of hello world can actually run. Since debugger relies
on nm(1) to get the symbol addresses, it doesn't work with ASLR and
plink uses -no-pie to link debug code.
Simple stuff seems to work, but there are quite a few problems.
E.g. while debug/libinfo.h has debug info for builtin stuff, it's
not actually available to the program/debugger as in the naive link
nothing refers debug info symbols and so they are not linked.
I fixed elisp/clu.el to work with modern emacs and added font-lock
support. I actually like its indentation style more, but Clu code in
the distribution uses cludent style. It would be nice to make the
style selectable, akin to c-set-style.
I've tested this procedure on Ubuntu/amd64 and NetBSD/macppc.
I have not yet tried a more recent version of gc (8.x). The original distribution had a rather old gc-7.2f. It worked for me on Ubuntu, so I stuck with it, upgrading to gc-7.2g eventually.
On NetBSD you will need to use gmake. On my 8-STABLE macppc I could
only get gc-7.2g to work and only with -O1.
The common idiom to compile Clu to C but don't compile the C output is
to use -ccopt 0 (bzw. -ccdbg 0). What makes the magic value 0
magic is ... its length. See cc_one in top2.clu - it won't do
anything if the command length is less than 4.