I have run the commands (adding -fPIC for linux). I can confirm that using
the resulting shared object does not crash Emacs. A bit of experimentation
reveals that the crash occurs only when the grammar is compiled with -O0.
However, despite not crashing, Emacs does not parse the file successfully,
although I agree this may be a separate issue.

On Mon, Oct 16, 2023 at 21:29 Eli Zaretskii <eliz@gnu.org> wrote:

> [Please use Reply All when replying to keep the bug tracker CC'ed.]
>
> > From: Erik Overdahl <erik.overdahl@gmail.com>
> > Date: Mon, 16 Oct 2023 18:21:26 -0500
> >
> > > After cloning the repository, I ran the following commands:
> > >
> > > cd src
> > > gcc -O2 -I. -MMD -MF ./parser.d -MP   -c -o parser.o parser.c
> > > gcc -O2 -I. -MMD -MF ./scanner.d -MP   -c -o scanner.o scanner.c
> > > gcc  -shared parser.o scanner.o  -ltree-sitter -o
> libtree-sitter-hcl.dll
> > >
> > > (This is on Windows, thus the .dll extension and no -fPIC compiler
> > > switch.)  Your link command line, viz.:
> > >
> > >  cc -fPIC -shared *.o -o libtree-sitter-hcl.so
> > >
> > > lacks the -ltree-sitter switch, though, which may or may not be the
> > > problem.
> >
> > If there is a problem with the command I used to build the grammar, then
> there is a problem with the
> > function `treesit-install-language-grammar`, as I copied the commands
> directly from there. I imagine
> > this is how most users would install this grammar?
>
> Maybe there is a problem, but please try compiling using the above
> commands, and see if the problem is gone.  We must establish the root
> cause before we assign blame or consider where and how to fix the
> problem.
>
> So: did the above commands fix the problem for you.
>
> > I have discovered another oddity.
>
> Thanks, but I'm not sure this is related.  I think we should focus on
> fixing the crash first.
>