Add some error checking, and stop assuming what the input
will necessarily contain. Allow defined nodes to use any
intN_t or unintN_t (as well as plain old int) data types
in fields (along with the others that are permitted).

Note: this script is a part of the build procedure for /bin/sh,
the modified version generates the exact same output files
(for the unaltered input specifications) as the previous one
did, hence no visible change is expected (or even possible).

While there is a tiny chance that some host shell will fail
to be able to run this script while building, the script still
uses nothing even slightly exotic, and is much more conservative
than other scripts used during the build process, so there should
be no issues there either.

Deal with ref after free found by ASAN when a function redefines
itself, or some other function which is still active.
This was a long known bug (fixed ages ago in the FreeBSD sh) which
hadn't been fixed as in practice, the situation that causes the
problem simply doesn't arise .. ASAN found it in the sh dotcmd
tests which do have this odd "feature" in the way they are written
(but where it never caused a problem, as the tests are so simple
that no mem is ever allocated between when the old version of the
function was deleted, and when it finished executing, so its code
all remained intact, despite having been freed.)

The fix is taken from the FreeBSD sh.

XXX -- pullup-8 (after a while to ensure no other problems arise).

branches: 1.2.56; 1.2.62;
Convert to new 2 clause license

branches: 1.1.30;
Replace the C program mknodes.c with a shell script mknodes.sh
(mkinit and mksyntax may also die soon...)

Deal with ref after free found by ASAN when a function redefines
itself, or some other function which is still active.
This was a long known bug (fixed ages ago in the FreeBSD sh) which
hadn't been fixed as in practice, the situation that causes the
problem simply doesn't arise .. ASAN found it in the sh dotcmd
tests which do have this odd "feature" in the way they are written
(but where it never caused a problem, as the tests are so simple
that no mem is ever allocated between when the old version of the
function was deleted, and when it finished executing, so its code
all remained intact, despite having been freed.)

The fix is taken from the FreeBSD sh.

XXX -- pullup-8 (after a while to ensure no other problems arise).

Convert to new 2 clause license

branches: 1.1.30;
Replace the C program mknodes.c with a shell script mknodes.sh
(mkinit and mksyntax may also die soon...)

Convert to new 2 clause license

branches: 1.1.30;
Replace the C program mknodes.c with a shell script mknodes.sh
(mkinit and mksyntax may also die soon...)

sync with head.