Hi Andrea,
 
Sorry for sending my previous mail to your address only and not to the bug tracker.
I'm not used to debbugs (as you can guess from the many HTML mails I sent, blush).

I wrote 
> > I do not understand 3b53a591faed03679382a601b93da7fe6ce3b4af: the way
You answered
> No you are right, this morning I was a little in a rush and I might have
> failed grepping, hopefully ab985f41db is better.

There are still problems related to the usage of Fdirectory_files and
internal_condition_case_5 I think.  At least, I get a crash after the
bootstrap is dumped (? see attached build log)

    Debugger entered--Lisp error: (wrong-type-argument wholenump t)

> With 407fb16583 I think '-lgccjit' should be unnecessary on Windows now, is it?

It is still needed, see my previous mail.  But adding -lgccjit allows the build
to proceed but crashes later on.

Can I propose a patch if I have not signed the paperwork?

Thank you for this great new feature.

These are the commands I ran to produce the attached build log:
#+begin_src shell :exports code
  (
      PROCESSORS_TO_USE="3"
      EMACS_VERSION="emacs-native-comp"
      cd ../emacs
      rm -rf ../build
      git restore .
      git status
      git rev-parse HEAD
      gcc --version
      ./autogen.sh
      mkdir -p ../build
      cd ../build
      ../emacs/configure \
          --with-xml2 \
          --without-pop \
          --prefix="/home/cramaph1/$EMACS_VERSION/dest" \
          --without-compress-install \
          --without-dbus \
          --with-nativecomp \
          --with-modules 'CFLAGS=-O2 -g3'
      # fix linker errors by making sure the correct libraries are added to the linker command
      sed -i -e 's/^LIBGCCJIT = *$/LIBGCCJIT = -lz -lgccjit/' src/Makefile
      make -j"$PROCESSORS_TO_USE"
      make install
  ) 2>&1 | tee /tmp/emacs-$(git rev-parse HEAD)-lz-lgccjit.log
#+end_src