I was able to successfully rebuild GCL (Version_2_6_13pre119) on a
system w/ GCC 9.
That GCL successfully compiles the current Git version of Maxima,
although it runs into a few errors in the main part of the test suite,
and then a large number of errors in the share tests. The share errors
seem to stem from only one or a few root causes, so it might be not
too difficult to fix them or work around them.
One kind of error is shown by:
f(x) :=x;
compile(f);
=> Maxima encountered a Lisp error:
Condition in MACSYMA-TOP-LEVEL [or a callee]: INTERNAL-SIMPLE-ERROR:
The assertion v && (unsigned long)(v+sz)<MAX_CODE_ADDRESS on line 1029
of alloc.c in function alloc_code_space failed: Success
However, that isn't entirely repeatable. I tried it again and it
failed again, but then I tried it again and it worked okay.
Another kind of error is shown by:
(%i1) load ("pslq");
filename_merge: unexpected argument:
"/home/dodier/maxima/maxima-code/share/pslq//pslq_integer_relation.lisp"
Looks like the problem is that the construct path contains "//"
instead of just "/".
best
Robert