diff --git a/.github/workflows/buildtoolchain.yml b/.github/workflows/buildtoolchain.yml
index 03e8e79..37353f7 100644
--- a/.github/workflows/buildtoolchain.yml
+++ b/.github/workflows/buildtoolchain.yml
@@ -15,7 +15,7 @@ jobs:
           submodules: "recursive"        
       - name: Install dependencies
         run: |
-          sudo apt-get install wget bzip2 xz-utils unzip git make tar flex bison diffutils texinfo gcc g++
+          sudo apt-get install wget bzip2 xz-utils unzip git make tar flex bison diffutils texinfo gcc g++ libexpat-dev
         shell: bash
       - name: Build toolchain
         run: |
@@ -50,7 +50,7 @@ jobs:
         uses: msys2/setup-msys2@v2.22.0
         with:
           msystem: MINGW64
-          install: git mingw-w64-x86_64-toolchain make wget bzip2 tar flex bison unzip diffutils texinfo autoconf patch
+          install: git mingw-w64-x86_64-toolchain make wget bzip2 tar flex bison unzip diffutils texinfo autoconf patch libexpat-devel
           update: true
       - name: Build toolchain
         run: |
diff --git a/buildtoolchain.sh b/buildtoolchain.sh
index c79571b..92743ff 100755
--- a/buildtoolchain.sh
+++ b/buildtoolchain.sh
@@ -269,7 +269,7 @@ function make_pio_package () {
     if [[ $OS = windows* ]]; then
         EXECUTEABLESUFFIX=".exe"
         echo "on windows, copy msys2 dlls"
-        for DLLFILE in msys-gcc_s-seh-1.dll msys-2.0.dll
+        for DLLFILE in msys-gcc_s-seh-1.dll msys-2.0.dll msys-stdc++-6.dll
         do
           cp  /usr/bin/$DLLFILE $HOSTINSTALLPATH/bin
         done
@@ -325,6 +325,26 @@ EOFLINUXVARIANT
 
 }
 
+function build_gdb () {
+#---------------------------------------------------------------------------------
+#build gdb
+
+log_msg ">>>> build gdb"
+
+
+
+GDBFLAGS+=" --target=$TARGETARCHITECTURE \
+            --prefix=$HOSTINSTALLPATH/ \
+            --with-gmp=$PREREQPATH/$GMPVER \
+            --with-mpfr=$PREREQPATH/$MPFRVER \
+            --with-expat
+ "
+
+
+conf_compile_source $GDBVER "$HOSTINSTALLPATH/bin/$TARGETARCHITECTURE-gdb$EXECUTEABLESUFFIX" "$GDBFLAGS"
+}
+
+
 if [ "$ACTION" = "purge" ]; then
     rm -rf $HOSTINSTALLPATH
     rm $ROOTDIR/*.log
@@ -345,6 +365,12 @@ if [ "$ACTION" = "download" ]; then
     exit 0
 fi
 
+if [ "$ACTION" = "build_gdb" ]; then
+    build_gdb
+    exit 0
+fi
+
+
 if [ "$ACTION" = "package" ]; then
     make_pio_package
     exit 0
@@ -632,22 +658,7 @@ log_msg "install $SOURCEPACKAGE finished"
 popd > /dev/null
 
 
-
-#---------------------------------------------------------------------------------
-#build gdb
-
-log_msg ">>>> build gdb"
-
-
-
-GDBFLAGS+=" --target=$TARGETARCHITECTURE \
-            --prefix=$HOSTINSTALLPATH/ \
-            --with-gmp=$PREREQPATH/$GMPVER \
-            --with-mpfr=$PREREQPATH/$MPFRVER \
- "
-
-
-conf_compile_source $GDBVER "$HOSTINSTALLPATH/bin/$TARGETARCHITECTURE-gdb$EXECUTEABLESUFFIX" "$GDBFLAGS"
+build_gdb
 
 make_pio_package
 
diff --git a/install_req_pkg_ubuntu-latest.sh b/install_req_pkg_ubuntu-latest.sh
index 03127a7..ac41c25 100644
--- a/install_req_pkg_ubuntu-latest.sh
+++ b/install_req_pkg_ubuntu-latest.sh
@@ -3,7 +3,7 @@
 # add your user to the sudoers
 
 # debian
-sudo apt-get install  wget bzip2 xz-utils unzip git make tar flex bison diffutils texinfo gcc g++ 
+sudo apt-get install  wget bzip2 xz-utils unzip git make tar flex bison diffutils texinfo gcc g++ libexpat-dev
 
 # ubuntu same ? - replace this by docker configurations !
 
diff --git a/install_req_pkg_windows-latest.sh b/install_req_pkg_windows-latest.sh
index a46f087..1d901c9 100644
--- a/install_req_pkg_windows-latest.sh
+++ b/install_req_pkg_windows-latest.sh
@@ -3,13 +3,15 @@
 # please use the MSYS2 shell, not the UCRT shell. 
 #
 # install MSYS2 package requirement for building the tool chain
-pacman -S --needed --noconfirm git msys2-runtime unzip make tar flex bison diffutils texinfo patch mingw-w64-x86_64-gcc mingw-w64-x86_64-libmangle-git mingw-w64-x86_64-make mingw-w64-x86_64-pkg-config mingw-w64-x86_64-tools-git mingw-w64-x86_64-winstorecompat-git
+pacman -S --needed --noconfirm git msys2-runtime unzip make tar flex bison diffutils texinfo patch mingw-w64-x86_64-gcc mingw-w64-x86_64-libmangle-git mingw-w64-x86_64-make mingw-w64-x86_64-pkg-config mingw-w64-x86_64-tools-git mingw-w64-x86_64-winstorecompat-git libexpat-devel
 
 ## all after this is only needed if avrdude shall use usb devices
 
 # pull additonal libraries (avrdude)
 #pacman -S --needed mingw-w64-x86_64-libusb mingw-w64-x86_64-libusb-compat-git mingw-w64-x86_64-libftdi cmake
 
+#mingw-w64-x86_64-libusb
+
 # nomally the avrdude should be updated to use the new libusb-1.0 but ...
 # 
 # quick and dirty hack: patch up msys  - there is an usb.h in the include path that shadows the usb.h