diff --git a/cli/src/gps-cli_kernels.adb b/cli/src/gps-cli_kernels.adb
index 042f8812d3..182c8e6843 100644
--- a/cli/src/gps-cli_kernels.adb
+++ b/cli/src/gps-cli_kernels.adb
@@ -18,6 +18,8 @@
 with GNATCOLL.Projects;
 with GNATCOLL.Utils;
 
+with Ada.Environment_Variables;
+
 package body GPS.CLI_Kernels is
 
    ---------------------
@@ -59,11 +61,14 @@ package body GPS.CLI_Kernels is
       return GNATCOLL.VFS.Virtual_File
    is
       pragma Unreferenced (Self);
+      use Ada.Environment_Variables;
 
       Dir : GNATCOLL.VFS.Virtual_File :=
         Create (+GNATCOLL.Utils.Executable_Location);
    begin
-      if Dir.Base_Dir_Name = "obj" then
+      if Exists ("XDG_DATA_DIRS") then
+         Dir := Create (+(Value ("XDG_DATA_DIRS")) & "/gnatstudio/");
+      elsif Dir.Base_Dir_Name = "obj" then
          Dir := Create_From_Dir (Dir.Get_Parent.Get_Parent, "share/");
       else
          Dir := Create_From_Dir (Dir, "share/gnatstudio/");
diff --git a/configure b/configure
index 98cd647848..048ec5fcf8 100755
--- a/configure
+++ b/configure
@@ -4387,7 +4387,14 @@ fi
   { $as_echo "$as_me:${as_lineno-$LINENO}: checking for GtkAda - version >= $min_gtk_version" >&5
 $as_echo_n "checking for GtkAda - version >= $min_gtk_version... " >&6; }
 
-  if test "$GNATDRV" = "no" -o ! `$GNATDRV ls -Pgtkada` ; then
+test ! "$GNATDRV" = "no"
+retval=$?
+if test $retval -eq 0 ; then
+    $GNATDRV ls -Pgtkada > /dev/null
+    retval=$?
+fi
+
+  if test $retval -ne 0 ; then
     no_gtk=yes
   else
     # Full version number
@@ -4579,7 +4586,7 @@ $as_echo_n "checking for $am_display_PYTHON version... " >&6; }
 if ${am_cv_python_version+:} false; then :
   $as_echo_n "(cached) " >&6
 else
-  am_cv_python_version=`$PYTHON -c "import sys; sys.stdout.write(sys.version[:3])"`
+  am_cv_python_version=`$PYTHON -c "import sys,re; sys.stdout.write(re.findall(r'(\d+\.\d+)\.', sys.version)[0])"`
 fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_python_version" >&5
 $as_echo "$am_cv_python_version" >&6; }
@@ -5101,7 +5108,7 @@ See \`config.log' for more details" "$LINENO" 5; }
 
 
 
-   value=$PYTHON_LIBS $PYTHON_EXTRA_LIBS $PYTHON_EXTRA_LDFLAGS
+   value="$PYTHON_LIBS $PYTHON_EXTRA_LIBS $PYTHON_EXTRA_LDFLAGS"
 
    # Special handling on darwin for gcc 4.5 and 4.7
    case "$build_os" in
diff --git a/dap/dap.gpr b/dap/dap.gpr
index 95814a1550..0c470ed528 100644
--- a/dap/dap.gpr
+++ b/dap/dap.gpr
@@ -7,7 +7,7 @@ with "../refactoring/ui/refactoring_ui";
 with "../views/views";
 with "../browsers/browsers";
 with "../gvd/gvd";
-with "../subprojects/VSS/gnat/vss_text";
+with "vss_text";
 
 project DAP is
 
diff --git a/share/support/core/gs_utils/__init__.py b/share/support/core/gs_utils/__init__.py
index 4850fc5324..02f20dcaca 100644
--- a/share/support/core/gs_utils/__init__.py
+++ b/share/support/core/gs_utils/__init__.py
@@ -2,7 +2,7 @@
 # exported by GPS to make it easier to write plugins
 
 from GPS import pwd, cd, Action, EditorBuffer, MDI
-from collections import MutableMapping as DictMixin
+from collections.abc import MutableMapping as DictMixin
 import types
 import GPS
 import GPS.Browsers
diff --git a/testsuite/Makefile b/testsuite/Makefile
index c97e52f41e..eca58db184 100644
--- a/testsuite/Makefile
+++ b/testsuite/Makefile
@@ -1,5 +1,6 @@
 GPRBUILD=gprbuild
 GPRCLEAN=gprclean
+BUILD?=Debug
 
 SYS := $(shell gcc -dumpmachine)
 ifeq ($(OS),Windows_NT)