diff --git a/.github/workflows/macos.yml b/.github/workflows/macos.yml
new file mode 100644
index 000000000..d45fb603f
--- /dev/null
+++ b/.github/workflows/macos.yml
@@ -0,0 +1,59 @@
+name: MacOS Workflow
+
+on:
+  pull_request:
+    branches:
+      - master
+      - gcos
+  push:
+    branches:
+      - master
+      - gcos
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        os:
+          - macos-latest
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
+      - uses: actions/checkout@v2
+
+      - name: Set git user
+        run: |
+          git config --global user.name github-actions
+          git config --global user.email github-actions-bot@users.noreply.github.com
+
+      - run: |
+          brew install automake libtool help2man texinfo bison
+          echo "/usr/local/opt/bison/bin" >> $GITHUB_PATH
+          echo "/usr/local/opt/texinfo/bin" >> $GITHUB_PATH
+
+      - name: ./build_aux/bootstrap
+        run: |
+          cd build_aux
+          ./bootstrap
+
+      - run: |
+          mkdir _build
+
+      - name: configure
+        run: |
+          cd _build
+          ../configure --enable-cobc-internal-checks --enable-debug --prefix /opt/cobol/gnucobol-gcos --exec-prefix /opt/cobol/gnucobol-gcos
+
+      - name: make
+        run: |
+          cd _build
+          make
+
+      - name: install
+        run: |
+          cd _build
+          sudo make install
+
diff --git a/.github/workflows/ubuntu.yml b/.github/workflows/ubuntu.yml
new file mode 100644
index 000000000..06f5628d9
--- /dev/null
+++ b/.github/workflows/ubuntu.yml
@@ -0,0 +1,61 @@
+name: Ubuntu Workflow
+
+on:
+  pull_request:
+    branches:
+      - master
+      - gcos
+  push:
+    branches:
+      - master
+      - gcos
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        os:
+          - ubuntu-latest
+#          - macos-latest
+
+        include:
+          - os: ubuntu-latest
+            skip_test: true
+
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
+      - uses: actions/checkout@v2
+
+      - name: Set git user
+        run: |
+          git config --global user.name github-actions
+          git config --global user.email github-actions-bot@users.noreply.github.com
+
+      - run: |
+          sudo apt-get install libdb5.3-dev help2man
+
+      - run: |
+          ./build_aux/bootstrap
+
+      - run: |
+          mkdir _build
+
+      - name: configure
+        run: |
+          cd _build
+          ../configure --enable-cobc-internal-checks --enable-debug --prefix /opt/cobol/gnucobol-gcos --exec-prefix /opt/cobol/gnucobol-gcos
+
+      - name: make
+        run: |
+          cd _build
+          make
+
+      - name: install
+        run: |
+          cd _build
+          make install
+
diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
new file mode 100644
index 000000000..05939fa9d
--- /dev/null
+++ b/.github/workflows/windows.yml
@@ -0,0 +1,62 @@
+name: Windows Workflow
+
+on:
+  pull_request:
+    branches:
+      - master
+      - gcos
+  push:
+    branches:
+      - master
+      - gcos
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        os:
+          - windows-latest
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
+      - uses: actions/checkout@v2
+
+      - name: Set git user
+        run: |
+          git config --global user.name github-actions
+          git config --global user.email github-actions-bot@users.noreply.github.com
+
+      - uses: msys2/setup-msys2@v2
+        with:
+          update: true
+          install: autoconf automake libtool make mingw-w64-x86_64-db mingw-w64-x86_64-gmp libdb-devel  mingw-w64-x86_64-gcc flex bison gmp-devel help2man texinfo
+
+      - run: |
+          ./build_aux/bootstrap
+        shell: msys2 {0}
+
+      - run: |
+          mkdir _build
+        shell: msys2 {0}
+
+      - name: configure
+        run: |
+          cd _build
+          ../configure --enable-cobc-internal-checks --enable-debug --prefix /opt/cobol/gnucobol-gcos --exec-prefix /opt/cobol/gnucobol-gcos
+        shell: msys2 {0}
+
+      - name: make
+        run: |
+          cd _build
+          make
+        shell: msys2 {0}
+
+      - name: install
+        run: |
+          cd _build
+          make install
+        shell: msys2 {0}
+
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 000000000..a2fa2e9b2
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,12 @@
+Makefile.in
+/_build
+aclocal.m4
+aminclude_static.am
+autom4te.cache
+config.h.in
+/configure
+/doc/gnucobol.info
+/doc/stamp-vti
+/doc/version.texi
+/tarstamp.h
+*~
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
new file mode 100644
index 000000000..cd8e2acad
--- /dev/null
+++ b/.gitlab-ci.yml
@@ -0,0 +1,13 @@
+build:
+  stage: build
+  image: registry.ocamlpro.com/ocamlpro/ocaml-docker-images:4.12
+  before_script:
+    - sudo apk add --upgrade --no-cache make patch gcc curl coreutils musl-dev opam git gmp-dev pkgconf libressl-dev emacs cmake  g++ boost boost-dev boost-static autoconf automake libtool help2man texinfo bison make gcc db-dev flex gawk bash
+  script:
+    - ./build_aux/bootstrap
+    - mkdir _build
+    - cd _build
+    - ../configure --enable-cobc-internal-checks --enable-debug --prefix /opt/cobol/gnucobol-gcos --exec-prefix /opt/cobol/gnucobol-gcos
+    - make
+    - sudo make install
+
diff --git a/build_aux/ar-lib b/build_aux/ar-lib
deleted file mode 120000
index be8806a2f..000000000
--- a/build_aux/ar-lib
+++ /dev/null
@@ -1,271 +0,0 @@
-#! /bin/sh
-# Wrapper for Microsoft lib.exe
-
-me=ar-lib
-scriptversion=2019-07-04.01; # UTC
-
-# Copyright (C) 2010-2019 Free Software Foundation, Inc.
-# Written by Peter Rosin <peda@lysator.liu.se>.
-#
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 2, or (at your option)
-# any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
-# As a special exception to the GNU General Public License, if you
-# distribute this file as part of a program that contains a
-# configuration script generated by Autoconf, you may include it under
-# the same distribution terms that you use for the rest of that program.
-
-# This file is maintained in Automake, please report
-# bugs to <bug-automake@gnu.org> or send patches to
-# <automake-patches@gnu.org>.
-
-
-# func_error message
-func_error ()
-{
-  echo "$me: $1" 1>&2
-  exit 1
-}
-
-file_conv=
-
-# func_file_conv build_file
-# Convert a $build file to $host form and store it in $file
-# Currently only supports Windows hosts.
-func_file_conv ()
-{
-  file=$1
-  case $file in
-    / | /[!/]*) # absolute file, and not a UNC file
-      if test -z "$file_conv"; then
-	# lazily determine how to convert abs files
-	case `uname -s` in
-	  MINGW*)
-	    file_conv=mingw
-	    ;;
-	  CYGWIN* | MSYS*)
-	    file_conv=cygwin
-	    ;;
-	  *)
-	    file_conv=wine
-	    ;;
-	esac
-      fi
-      case $file_conv in
-	mingw)
-	  file=`cmd //C echo "$file " | sed -e 's/"\(.*\) " *$/\1/'`
-	  ;;
-	cygwin | msys)
-	  file=`cygpath -m "$file" || echo "$file"`
-	  ;;
-	wine)
-	  file=`winepath -w "$file" || echo "$file"`
-	  ;;
-      esac
-      ;;
-  esac
-}
-
-# func_at_file at_file operation archive
-# Iterate over all members in AT_FILE performing OPERATION on ARCHIVE
-# for each of them.
-# When interpreting the content of the @FILE, do NOT use func_file_conv,
-# since the user would need to supply preconverted file names to
-# binutils ar, at least for MinGW.
-func_at_file ()
-{
-  operation=$2
-  archive=$3
-  at_file_contents=`cat "$1"`
-  eval set x "$at_file_contents"
-  shift
-
-  for member
-  do
-    $AR -NOLOGO $operation:"$member" "$archive" || exit $?
-  done
-}
-
-case $1 in
-  '')
-     func_error "no command.  Try '$0 --help' for more information."
-     ;;
-  -h | --h*)
-    cat <<EOF
-Usage: $me [--help] [--version] PROGRAM ACTION ARCHIVE [MEMBER...]
-
-Members may be specified in a file named with @FILE.
-EOF
-    exit $?
-    ;;
-  -v | --v*)
-    echo "$me, version $scriptversion"
-    exit $?
-    ;;
-esac
-
-if test $# -lt 3; then
-  func_error "you must specify a program, an action and an archive"
-fi
-
-AR=$1
-shift
-while :
-do
-  if test $# -lt 2; then
-    func_error "you must specify a program, an action and an archive"
-  fi
-  case $1 in
-    -lib | -LIB \
-    | -ltcg | -LTCG \
-    | -machine* | -MACHINE* \
-    | -subsystem* | -SUBSYSTEM* \
-    | -verbose | -VERBOSE \
-    | -wx* | -WX* )
-      AR="$AR $1"
-      shift
-      ;;
-    *)
-      action=$1
-      shift
-      break
-      ;;
-  esac
-done
-orig_archive=$1
-shift
-func_file_conv "$orig_archive"
-archive=$file
-
-# strip leading dash in $action
-action=${action#-}
-
-delete=
-extract=
-list=
-quick=
-replace=
-index=
-create=
-
-while test -n "$action"
-do
-  case $action in
-    d*) delete=yes  ;;
-    x*) extract=yes ;;
-    t*) list=yes    ;;
-    q*) quick=yes   ;;
-    r*) replace=yes ;;
-    s*) index=yes   ;;
-    S*)             ;; # the index is always updated implicitly
-    c*) create=yes  ;;
-    u*)             ;; # TODO: don't ignore the update modifier
-    v*)             ;; # TODO: don't ignore the verbose modifier
-    *)
-      func_error "unknown action specified"
-      ;;
-  esac
-  action=${action#?}
-done
-
-case $delete$extract$list$quick$replace,$index in
-  yes,* | ,yes)
-    ;;
-  yesyes*)
-    func_error "more than one action specified"
-    ;;
-  *)
-    func_error "no action specified"
-    ;;
-esac
-
-if test -n "$delete"; then
-  if test ! -f "$orig_archive"; then
-    func_error "archive not found"
-  fi
-  for member
-  do
-    case $1 in
-      @*)
-        func_at_file "${1#@}" -REMOVE "$archive"
-        ;;
-      *)
-        func_file_conv "$1"
-        $AR -NOLOGO -REMOVE:"$file" "$archive" || exit $?
-        ;;
-    esac
-  done
-
-elif test -n "$extract"; then
-  if test ! -f "$orig_archive"; then
-    func_error "archive not found"
-  fi
-  if test $# -gt 0; then
-    for member
-    do
-      case $1 in
-        @*)
-          func_at_file "${1#@}" -EXTRACT "$archive"
-          ;;
-        *)
-          func_file_conv "$1"
-          $AR -NOLOGO -EXTRACT:"$file" "$archive" || exit $?
-          ;;
-      esac
-    done
-  else
-    $AR -NOLOGO -LIST "$archive" | tr -d '\r' | sed -e 's/\\/\\\\/g' \
-      | while read member
-        do
-          $AR -NOLOGO -EXTRACT:"$member" "$archive" || exit $?
-        done
-  fi
-
-elif test -n "$quick$replace"; then
-  if test ! -f "$orig_archive"; then
-    if test -z "$create"; then
-      echo "$me: creating $orig_archive"
-    fi
-    orig_archive=
-  else
-    orig_archive=$archive
-  fi
-
-  for member
-  do
-    case $1 in
-    @*)
-      func_file_conv "${1#@}"
-      set x "$@" "@$file"
-      ;;
-    *)
-      func_file_conv "$1"
-      set x "$@" "$file"
-      ;;
-    esac
-    shift
-    shift
-  done
-
-  if test -n "$orig_archive"; then
-    $AR -NOLOGO -OUT:"$archive" "$orig_archive" "$@" || exit $?
-  else
-    $AR -NOLOGO -OUT:"$archive" "$@" || exit $?
-  fi
-
-elif test -n "$list"; then
-  if test ! -f "$orig_archive"; then
-    func_error "archive not found"
-  fi
-  $AR -NOLOGO -LIST "$archive" || exit $?
-fi
diff --git a/build_aux/ar-lib b/build_aux/ar-lib
new file mode 100644
index 000000000..be8806a2f
--- /dev/null
+++ b/build_aux/ar-lib
@@ -0,0 +1,271 @@
+#! /bin/sh
+# Wrapper for Microsoft lib.exe
+
+me=ar-lib
+scriptversion=2019-07-04.01; # UTC
+
+# Copyright (C) 2010-2019 Free Software Foundation, Inc.
+# Written by Peter Rosin <peda@lysator.liu.se>.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+# As a special exception to the GNU General Public License, if you
+# distribute this file as part of a program that contains a
+# configuration script generated by Autoconf, you may include it under
+# the same distribution terms that you use for the rest of that program.
+
+# This file is maintained in Automake, please report
+# bugs to <bug-automake@gnu.org> or send patches to
+# <automake-patches@gnu.org>.
+
+
+# func_error message
+func_error ()
+{
+  echo "$me: $1" 1>&2
+  exit 1
+}
+
+file_conv=
+
+# func_file_conv build_file
+# Convert a $build file to $host form and store it in $file
+# Currently only supports Windows hosts.
+func_file_conv ()
+{
+  file=$1
+  case $file in
+    / | /[!/]*) # absolute file, and not a UNC file
+      if test -z "$file_conv"; then
+	# lazily determine how to convert abs files
+	case `uname -s` in
+	  MINGW*)
+	    file_conv=mingw
+	    ;;
+	  CYGWIN* | MSYS*)
+	    file_conv=cygwin
+	    ;;
+	  *)
+	    file_conv=wine
+	    ;;
+	esac
+      fi
+      case $file_conv in
+	mingw)
+	  file=`cmd //C echo "$file " | sed -e 's/"\(.*\) " *$/\1/'`
+	  ;;
+	cygwin | msys)
+	  file=`cygpath -m "$file" || echo "$file"`
+	  ;;
+	wine)
+	  file=`winepath -w "$file" || echo "$file"`
+	  ;;
+      esac
+      ;;
+  esac
+}
+
+# func_at_file at_file operation archive
+# Iterate over all members in AT_FILE performing OPERATION on ARCHIVE
+# for each of them.
+# When interpreting the content of the @FILE, do NOT use func_file_conv,
+# since the user would need to supply preconverted file names to
+# binutils ar, at least for MinGW.
+func_at_file ()
+{
+  operation=$2
+  archive=$3
+  at_file_contents=`cat "$1"`
+  eval set x "$at_file_contents"
+  shift
+
+  for member
+  do
+    $AR -NOLOGO $operation:"$member" "$archive" || exit $?
+  done
+}
+
+case $1 in
+  '')
+     func_error "no command.  Try '$0 --help' for more information."
+     ;;
+  -h | --h*)
+    cat <<EOF
+Usage: $me [--help] [--version] PROGRAM ACTION ARCHIVE [MEMBER...]
+
+Members may be specified in a file named with @FILE.
+EOF
+    exit $?
+    ;;
+  -v | --v*)
+    echo "$me, version $scriptversion"
+    exit $?
+    ;;
+esac
+
+if test $# -lt 3; then
+  func_error "you must specify a program, an action and an archive"
+fi
+
+AR=$1
+shift
+while :
+do
+  if test $# -lt 2; then
+    func_error "you must specify a program, an action and an archive"
+  fi
+  case $1 in
+    -lib | -LIB \
+    | -ltcg | -LTCG \
+    | -machine* | -MACHINE* \
+    | -subsystem* | -SUBSYSTEM* \
+    | -verbose | -VERBOSE \
+    | -wx* | -WX* )
+      AR="$AR $1"
+      shift
+      ;;
+    *)
+      action=$1
+      shift
+      break
+      ;;
+  esac
+done
+orig_archive=$1
+shift
+func_file_conv "$orig_archive"
+archive=$file
+
+# strip leading dash in $action
+action=${action#-}
+
+delete=
+extract=
+list=
+quick=
+replace=
+index=
+create=
+
+while test -n "$action"
+do
+  case $action in
+    d*) delete=yes  ;;
+    x*) extract=yes ;;
+    t*) list=yes    ;;
+    q*) quick=yes   ;;
+    r*) replace=yes ;;
+    s*) index=yes   ;;
+    S*)             ;; # the index is always updated implicitly
+    c*) create=yes  ;;
+    u*)             ;; # TODO: don't ignore the update modifier
+    v*)             ;; # TODO: don't ignore the verbose modifier
+    *)
+      func_error "unknown action specified"
+      ;;
+  esac
+  action=${action#?}
+done
+
+case $delete$extract$list$quick$replace,$index in
+  yes,* | ,yes)
+    ;;
+  yesyes*)
+    func_error "more than one action specified"
+    ;;
+  *)
+    func_error "no action specified"
+    ;;
+esac
+
+if test -n "$delete"; then
+  if test ! -f "$orig_archive"; then
+    func_error "archive not found"
+  fi
+  for member
+  do
+    case $1 in
+      @*)
+        func_at_file "${1#@}" -REMOVE "$archive"
+        ;;
+      *)
+        func_file_conv "$1"
+        $AR -NOLOGO -REMOVE:"$file" "$archive" || exit $?
+        ;;
+    esac
+  done
+
+elif test -n "$extract"; then
+  if test ! -f "$orig_archive"; then
+    func_error "archive not found"
+  fi
+  if test $# -gt 0; then
+    for member
+    do
+      case $1 in
+        @*)
+          func_at_file "${1#@}" -EXTRACT "$archive"
+          ;;
+        *)
+          func_file_conv "$1"
+          $AR -NOLOGO -EXTRACT:"$file" "$archive" || exit $?
+          ;;
+      esac
+    done
+  else
+    $AR -NOLOGO -LIST "$archive" | tr -d '\r' | sed -e 's/\\/\\\\/g' \
+      | while read member
+        do
+          $AR -NOLOGO -EXTRACT:"$member" "$archive" || exit $?
+        done
+  fi
+
+elif test -n "$quick$replace"; then
+  if test ! -f "$orig_archive"; then
+    if test -z "$create"; then
+      echo "$me: creating $orig_archive"
+    fi
+    orig_archive=
+  else
+    orig_archive=$archive
+  fi
+
+  for member
+  do
+    case $1 in
+    @*)
+      func_file_conv "${1#@}"
+      set x "$@" "@$file"
+      ;;
+    *)
+      func_file_conv "$1"
+      set x "$@" "$file"
+      ;;
+    esac
+    shift
+    shift
+  done
+
+  if test -n "$orig_archive"; then
+    $AR -NOLOGO -OUT:"$archive" "$orig_archive" "$@" || exit $?
+  else
+    $AR -NOLOGO -OUT:"$archive" "$@" || exit $?
+  fi
+
+elif test -n "$list"; then
+  if test ! -f "$orig_archive"; then
+    func_error "archive not found"
+  fi
+  $AR -NOLOGO -LIST "$archive" || exit $?
+fi