diff --git a/build.sh b/build.sh
index 81baa63ba..5bce6caaa 100755
--- a/build.sh
+++ b/build.sh
@@ -37,6 +37,7 @@ RUBYVERSIONCODE=""
 
 PYTHONINCLUDE=""
 PYTHONLIBFILE=""
+PYTHONEXTSUFFIX=""
 
 QMAKE=""
 RUBY=""
@@ -111,6 +112,10 @@ while [ "$*" != "" ]; do
     PYTHONLIBFILE="$1"
     shift
     ;;
+  -pyextsuffix)
+    PYTHONEXTSUFFIX="$1"
+    shift
+    ;;
   -qmake)
     QMAKE="$1"
     shift
@@ -414,6 +419,11 @@ if [ "$PYTHON" != "" ] && [ "$PYTHON" != "-" ]; then
     echo "    Python headers found: $PYTHONINCLUDE"
   fi
 
+  if [ "$PYTHONEXTSUFFIX" = "" ]; then
+    PYTHONEXTSUFFIX=`$PYTHON -c "import sysconfig; print(sysconfig.get_config_vars('EXT_SUFFIX')[0])" 2>/dev/null`
+    echo "    Python extension suffix: $PYTHONEXTSUFFIX"
+  fi
+
   echo "    Python installation is in:"
   echo "    - $PYTHONLIBFILE (lib)"
   echo "    - $PYTHONINCLUDE (includes)"
@@ -552,6 +562,7 @@ qmake_options=(
   PYTHON="$PYTHON"
   PYTHONLIBFILE="$PYTHONLIBFILE"
   PYTHONINCLUDE="$PYTHONINCLUDE"
+  PYTHONEXTSUFFIX="$PYTHONEXTSUFFIX"
   HAVE_PYTHON="$HAVE_PYTHON"
   HAVE_QTBINDINGS="$HAVE_QTBINDINGS"
   HAVE_64BIT_COORD="$HAVE_64BIT_COORD"
diff --git a/src/buddies/unit_tests/bdStrmrunTests.cc b/src/buddies/unit_tests/bdStrmrunTests.cc
index 18e674af1..60187733b 100644
--- a/src/buddies/unit_tests/bdStrmrunTests.cc
+++ b/src/buddies/unit_tests/bdStrmrunTests.cc
@@ -22,6 +22,7 @@
 
 #include "tlUnitTest.h"
 #include "tlStream.h"
+#include "tlFileUtils.h"
 
 //  Testing the converter main implementation (CIF)
 TEST(1)
@@ -29,7 +30,7 @@ TEST(1)
   std::string fp (tl::testsrc ());
   fp += "/testdata/bd/strmrun.py";
 
-  std::string path = "./strmrun " + fp;
+  std::string path = tl::combine_path (".", "strmrun ") + fp;
   tl::InputPipe pipe (path);
   tl::InputStream is (pipe);
   std::string data = is.read_all ();
diff --git a/src/db/db/dbInit.cc b/src/db/db/dbInit.cc
index 8608ecbe2..ec0879079 100644
--- a/src/db/db/dbInit.cc
+++ b/src/db/db/dbInit.cc
@@ -59,7 +59,7 @@ static PluginDescriptor load_plugin (const std::string &pp)
 #if defined(_WIN32)
 
   //  there is no "dlopen" on mingw, so we need to emulate it.
-  HINSTANCE handle = LoadLibraryW ((const wchar_t *) tl::to_qstring (pp).constData ());
+  HINSTANCE handle = LoadLibraryW (tl::to_wstring (pp).c_str ());
   if (! handle) {
     throw tl::Exception (tl::to_string (tr ("Unable to load plugin: %s with error message: %s ")), pp, GetLastError ());
     return desc;
diff --git a/src/gsi/gsi/gsi.pro b/src/gsi/gsi/gsi.pro
index 9b839c2f1..e02314d09 100644
--- a/src/gsi/gsi/gsi.pro
+++ b/src/gsi/gsi/gsi.pro
@@ -20,6 +20,7 @@ SOURCES = \
   gsiObject.cc \
   gsiSerialisation.cc \
   gsiTypes.cc \
+  gsiSignals.cc \
   gsiObjectHolder.cc \
 
 HEADERS = \
diff --git a/src/gsi/gsi/gsiSignals.cc b/src/gsi/gsi/gsiSignals.cc
new file mode 100644
index 000000000..fcd24adcd
--- /dev/null
+++ b/src/gsi/gsi/gsiSignals.cc
@@ -0,0 +1,32 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2018 Matthias Koefferlein
+
+  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 of the License, 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, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#include "gsiSignals.h"
+
+namespace gsi
+{
+
+// .. nothing yet ..
+
+}
+
diff --git a/src/pya/pya/pya.cc b/src/pya/pya/pya.cc
index bc9e09d43..93fb9354b 100644
--- a/src/pya/pya/pya.cc
+++ b/src/pya/pya/pya.cc
@@ -38,11 +38,17 @@
 #include "tlStream.h"
 #include "tlTimer.h"
 #include "tlFileUtils.h"
+#include "tlString.h"
 
 #if defined(HAVE_QT)
 #  include <QCoreApplication>
 #endif
 
+//  For the installation path
+#ifdef _WIN32
+#  include <windows.h>
+#endif
+
 namespace pya
 {
 
@@ -195,37 +201,41 @@ PythonInterpreter::PythonInterpreter ()
 
     try {
 
-      QString path;
+      std::string path;
 
-      QDir inst_dir (QCoreApplication::applicationDirPath ());
-      QFileInfo fi (inst_dir.absoluteFilePath (tl::to_qstring(".python-paths.txt")));
-      if (fi.exists ()) {
+      wchar_t buffer[MAX_PATH];
+      int len;
+      if ((len = GetModuleFileName (NULL, buffer, MAX_PATH)) > 0) {
 
-        tl::log << tl::to_string (tr ("Reading Python path from ")) << tl::to_string (fi.filePath ());
+        std::string inst_dir = tl::absolute_path (tl::to_string (std::wstring (buffer, len)));
+        std::string path_file = tl::combine_path (inst_dir, ".python-paths.txt");
+        if (tl::file_exists (path_file)) {
 
-        QFile paths_txt (fi.filePath ());
-        paths_txt.open (QIODevice::ReadOnly);
+          tl::log << tl::to_string (tr ("Reading Python path from ")) << path_file;
 
-        tl::Eval eval;
-        eval.set_global_var ("inst_path", tl::Variant (tl::to_string (inst_dir.absolutePath ())));
-        tl::Expression ex;
-        eval.parse (ex, paths_txt.readAll ().constData ());
-        tl::Variant v = ex.execute ();
+          tl::InputStream path_file_stream (path_file);
+          std::string path_file_text = path_file_stream.read_all ();
 
-        if (v.is_list ()) {
-          for (tl::Variant::iterator i = v.begin (); i != v.end (); ++i) {
-            if (! path.isEmpty ()) {
-              path += tl::to_qstring (";");
+          tl::Eval eval;
+          eval.set_global_var ("inst_path", tl::Variant (inst_dir));
+          tl::Expression ex;
+          eval.parse (ex, path_file_text.c_str ());
+          tl::Variant v = ex.execute ();
+
+          if (v.is_list ()) {
+            for (tl::Variant::iterator i = v.begin (); i != v.end (); ++i) {
+              if (! path.empty ()) {
+                path += ";";
+              }
+              path += i->to_string ();
             }
-            path += tl::to_qstring (i->to_string ());
           }
+
         }
 
       }
 
-      //  note: this is a hack, but linking with toWCharArray fails since wchar_t is treated
-      //  as a built-in type in our build
-      Py_SetPath ((const wchar_t *) path.utf16 ());
+      Py_SetPath (tl::to_wstring (path).c_str ());
 
     } catch (tl::Exception &ex) {
       tl::error << tl::to_string (tr ("Evaluation of Python path expression failed")) << ": " << ex.msg ();
diff --git a/src/pya/unit_tests/pya.cc b/src/pya/unit_tests/pya.cc
index 2d1ee6652..45c263d28 100644
--- a/src/pya/unit_tests/pya.cc
+++ b/src/pya/unit_tests/pya.cc
@@ -103,7 +103,7 @@ PYTHONTEST (dbPCellsTest, "dbPCells.py")
 PYTHONTEST (dbPolygonTest, "dbPolygonTest.py")
 PYTHONTEST (dbTransTest, "dbTransTest.py")
 PYTHONTEST (tlTest, "tlTest.py")
-#if defined(HAVE_QTBINDINGS)
+#if defined(HAVE_QT) && defined(HAVE_QTBINDINGS)
 PYTHONTEST (qtbinding, "qtbinding.py")
 #endif
 
diff --git a/src/pymod/pymod.pri b/src/pymod/pymod.pri
index a1d393c08..778d5ccd9 100644
--- a/src/pymod/pymod.pri
+++ b/src/pymod/pymod.pri
@@ -20,26 +20,22 @@ QMAKE_CXXFLAGS_WARN_ON += \
 # $(DESTDIR) and $(TARGET)
 win32 {
 
-  QMAKE_POST_LINK += $(MKDIR) $$DESTDIR_PYMOD && $(COPY) $(DESTDIR_TARGET) $$DESTDIR_PYMOD/$${TARGET}.dll
+  QMAKE_POST_LINK += $(MKDIR) $$DESTDIR_PYMOD && $(COPY) $(DESTDIR_TARGET) $$DESTDIR_PYMOD/$${TARGET}$${PYTHONEXTSUFFIX}
 
   # to avoid the major version being appended to the dll name - in this case -lxyz won't link it again
   # because the library is called xyx0.dll.
   CONFIG += skip_target_version_ext
 
-  lib_target.path = $$PREFIX/pymod/klayout
-  lib_target.files += $$DESTDIR_PYMOD/$${TARGET}.dll
-  INSTALLS = lib_target
-
 } else {
 
-  QMAKE_POST_LINK += $(MKDIR) $$DESTDIR_PYMOD && $(COPY) $(DESTDIR)$(TARGET) $$DESTDIR_PYMOD/$${TARGET}.so
-
-  lib_target.path = $$PREFIX/pymod/klayout
-  # This would be nice:
-  #   lib_target.files += $$DESTDIR_PYMOD/$${TARGET}.so
-  # but some Qt versions need this explicitly:
-  lib_target.extra = $(INSTALL_PROGRAM) $$DESTDIR_PYMOD/$${TARGET}.so $(INSTALLROOT)$$PREFIX/pymod/klayout
-  INSTALLS = lib_target
+  QMAKE_POST_LINK += $(MKDIR) $$DESTDIR_PYMOD && $(COPY) $(DESTDIR)$(TARGET) $$DESTDIR_PYMOD/$${TARGET}$${PYTHONEXTSUFFIX}
 
 }
 
+lib_target.path = $$PREFIX/pymod/klayout
+# This would be nice:
+#   lib_target.files += $$DESTDIR_PYMOD/$${TARGET}$${PYTHONEXTSUFFIX}
+# but some Qt versions need this explicitly:
+lib_target.extra = $(INSTALL_PROGRAM) $$DESTDIR_PYMOD/$${TARGET}$${PYTHONEXTSUFFIX} $(INSTALLROOT)$$PREFIX/pymod/klayout
+INSTALLS = lib_target
+
diff --git a/src/pymod/unit_tests/pymod_tests.cc b/src/pymod/unit_tests/pymod_tests.cc
index c456dfeb3..c80b81a8e 100644
--- a/src/pymod/unit_tests/pymod_tests.cc
+++ b/src/pymod/unit_tests/pymod_tests.cc
@@ -66,7 +66,7 @@ PYMODTEST (import_tl, "import_tl.py")
 PYMODTEST (import_db, "import_db.py")
 PYMODTEST (import_rdb, "import_rdb.py")
 
-#if defined(HAVE_QTBINDINGS)
+#if defined(HAVE_QT) && defined(HAVE_QTBINDINGS)
 
 PYMODTEST (import_lay, "import_lay.py")
 
diff --git a/src/rba/rba/rba.cc b/src/rba/rba/rba.cc
index 89995e310..ec6cb898f 100644
--- a/src/rba/rba/rba.cc
+++ b/src/rba/rba/rba.cc
@@ -34,6 +34,7 @@
 #include "tlTimer.h"
 #include "tlExpression.h"
 #include "tlFileUtils.h"
+#include "tlStream.h"
 
 #include "rba.h"
 #include "rbaInspector.h"
@@ -1812,21 +1813,21 @@ RubyInterpreter::initialize (int &main_argc, char **main_argv, int (*main_func)
 
         wchar_t buffer[MAX_PATH];
         int len;
-        if ((len = GetModuleFileName(NULL, buffer, MAX_PATH)) > 0) {
+        if ((len = GetModuleFileName (NULL, buffer, MAX_PATH)) > 0) {
 
-          QDir inst_dir (QString::fromUtf16 ((const ushort *) buffer, len));
-          QFileInfo fi (inst_dir.absoluteFilePath (tl::to_qstring(".ruby-paths.txt")));
-          if (fi.exists ()) {
+          std::string inst_dir = tl::absolute_path (tl::to_string (std::wstring (buffer, len)));
+          std::string path_file = tl::combine_path (inst_dir, ".ruby-paths.txt");
+          if (tl::file_exists (path_file)) {
 
-            tl::log << tl::to_string (tr ("Reading Ruby path from ")) << tl::to_string (fi.filePath ());
+            tl::log << tl::to_string (tr ("Reading Ruby path from ")) << path_file;
 
-            QFile paths_txt (fi.filePath ());
-            paths_txt.open (QIODevice::ReadOnly);
+            tl::InputStream path_file_stream (path_file);
+            std::string path_file_text = path_file_stream.read_all ();
 
             tl::Eval eval;
-            eval.set_global_var ("inst_path", tl::Variant (tl::to_string (inst_dir.absolutePath ())));
+            eval.set_global_var ("inst_path", tl::Variant (inst_dir));
             tl::Expression ex;
-            eval.parse (ex, paths_txt.readAll ().constData ());
+            eval.parse (ex, path_file_text.c_str ());
             tl::Variant v = ex.execute ();
 
             if (v.is_list ()) {
diff --git a/src/rba/unit_tests/rba.cc b/src/rba/unit_tests/rba.cc
index 14166891f..d5acbf36c 100644
--- a/src/rba/unit_tests/rba.cc
+++ b/src/rba/unit_tests/rba.cc
@@ -34,7 +34,7 @@ TEST (1)
 {
   EXPECT_EQ (gsi::has_class ("Value"), true);
   EXPECT_EQ (gsi::has_class ("DoesNotExist"), false);
-#if defined(HAVE_QTBINDINGS)
+#if defined(HAVE_QT) && defined(HAVE_QTBINDINGS)
   EXPECT_EQ (gsi::has_class ("QDialog"), true);
   EXPECT_EQ (gsi::has_class ("QApplication"), true);
 #endif
@@ -131,7 +131,7 @@ RUBYTEST (layMenuTest, "layMenuTest.rb")
 RUBYTEST (laySession, "laySession.rb")
 RUBYTEST (layTechnologies, "layTechnologies.rb")
 RUBYTEST (laySaveLayoutOptions, "laySaveLayoutOptions.rb")
-#if defined(HAVE_QTBINDINGS)
+#if defined(HAVE_QT) && defined(HAVE_QTBINDINGS)
 RUBYTEST (qtbinding, "qtbinding.rb")
 #endif
 RUBYTEST (rdbTest, "rdbTest.rb")
diff --git a/src/tl/tl/tlFileUtils.cc b/src/tl/tl/tlFileUtils.cc
index a17e7d5a6..dede3f6ce 100644
--- a/src/tl/tl/tlFileUtils.cc
+++ b/src/tl/tl/tlFileUtils.cc
@@ -31,6 +31,11 @@
 #include <unistd.h>
 #include <dirent.h>
 
+#if defined(_WIN32)
+#  include <dir.h>
+#  include <windows.h>
+#endif
+
 namespace tl
 {
 
@@ -306,7 +311,7 @@ std::vector<std::string> dir_entries (const std::string &s, bool with_files, boo
 
     do {
 
-      std::string e = tl::to_string fileinfo.name);
+      std::string e = tl::to_string (std::wstring (fileinfo.name));
       if (e.empty () || e == "." || e == "..") {
         continue;
       }
@@ -320,7 +325,7 @@ std::vector<std::string> dir_entries (const std::string &s, bool with_files, boo
 
   }
 
-  _wfindclose (h);
+  _findclose (h);
 
 #else
 
@@ -615,24 +620,35 @@ std::string absolute_file_path (const std::string &s)
   }
 }
 
-static int stat_func (const std::string &s, struct stat &st)
-{
 #if defined(_WIN32)
+
+typedef struct _stat stat_struct;
+
+static int stat_func (const std::string &s, stat_struct &st)
+{
   return _wstat (tl::to_wstring (s).c_str (), &st);
-#else
-  return stat (tl::to_local (s).c_str (), &st);
-#endif
 }
 
+#else
+
+typedef struct stat stat_struct;
+
+static int stat_func (const std::string &s, stat_struct &st)
+{
+  return stat (tl::to_local (s).c_str (), &st);
+}
+
+#endif
+
 bool file_exists (const std::string &p)
 {
-  struct stat st;
+  stat_struct st;
   return stat_func (p, st) == 0;
 }
 
 bool is_dir (const std::string &p)
 {
-  struct stat st;
+  stat_struct st;
   if (stat_func (p, st) != 0) {
     return false;
   } else {
@@ -700,7 +716,7 @@ bool is_same_file (const std::string &a, const std::string &b)
 
 #else
 
-  struct stat sta, stb;
+  stat_struct sta, stb;
   if (stat_func (a, sta) != 0 || stat_func (b, stb) != 0) {
     return false;
   }
diff --git a/src/tl/tl/tlStream.cc b/src/tl/tl/tlStream.cc
index 33124c45b..8de7fe508 100644
--- a/src/tl/tl/tlStream.cc
+++ b/src/tl/tl/tlStream.cc
@@ -469,7 +469,7 @@ InputFile::InputFile (const std::string &path)
 {
   m_source = path;
 #if defined(_WIN32)
-  int fd = _wopen ((const wchar_t *) tl::to_qstring (path).constData (), _O_BINARY | _O_RDONLY | _O_SEQUENTIAL);
+  int fd = _wopen (tl::to_wstring (path).c_str (), _O_BINARY | _O_RDONLY | _O_SEQUENTIAL);
   if (fd < 0) {
     throw FileOpenErrorException (m_source, errno);
   }
@@ -550,7 +550,7 @@ InputZLibFile::InputZLibFile (const std::string &path)
 {
   m_source = path;
 #if defined(_WIN32)
-  int fd = _wopen ((const wchar_t *) tl::to_qstring (path).constData (), _O_BINARY | _O_RDONLY | _O_SEQUENTIAL);
+  int fd = _wopen (tl::to_wstring (path).c_str (), _O_BINARY | _O_RDONLY | _O_SEQUENTIAL);
   if (fd < 0) {
     throw FileOpenErrorException (m_source, errno);
   }
@@ -763,7 +763,7 @@ OutputFile::OutputFile (const std::string &path)
 {
   m_source = path;
 #if defined(_WIN32)
-  int fd = _wopen ((const wchar_t *) tl::to_qstring (path).constData (), _O_CREAT | _O_TRUNC | _O_BINARY | _O_WRONLY | _O_SEQUENTIAL, _S_IREAD | _S_IWRITE );
+  int fd = _wopen (tl::to_wstring (path).c_str (), _O_CREAT | _O_TRUNC | _O_BINARY | _O_WRONLY | _O_SEQUENTIAL, _S_IREAD | _S_IWRITE );
   if (fd < 0) {
     throw FileOpenErrorException (m_source, errno);
   }
@@ -824,7 +824,7 @@ OutputZLibFile::OutputZLibFile (const std::string &path)
 {
   m_source = path;
 #if defined(_WIN32)
-  FILE *file = _wfopen ((const wchar_t *) tl::to_qstring (path).constData (), L"wb");
+  FILE *file = _wfopen (tl::to_wstring (path).c_str (), L"wb");
   if (file == NULL) {
     throw FileOpenErrorException (m_source, errno);
   }
@@ -871,7 +871,7 @@ InputPipe::InputPipe (const std::string &path)
 {
   std::wstring wpath = tl::to_wstring (path);
   m_source = path;
-  m_file = _wpopen (wpath.c_str (), "r");
+  m_file = _wpopen (wpath.c_str (), L"r");
   if (m_file == NULL) {
     throw FilePOpenErrorException (m_source, errno);
   }
@@ -919,7 +919,7 @@ OutputPipe::OutputPipe (const std::string &path)
 {
   std::wstring wpath = tl::to_wstring (path);
   m_source = path;
-  m_file = _wpopen (wpath.c_str (), "w");
+  m_file = _wpopen (wpath.c_str (), L"w");
   if (m_file == NULL) {
     throw FilePOpenErrorException (m_source, errno);
   }
diff --git a/src/tl/tl/tlString.cc b/src/tl/tl/tlString.cc
index 84488aecf..9a4d885c5 100644
--- a/src/tl/tl/tlString.cc
+++ b/src/tl/tl/tlString.cc
@@ -86,6 +86,7 @@ std::string to_string (const std::wstring &ws)
       ++c;
       c32 = (c32 & 0x3ff) << 10;
       c32 |= uint32_t (*c) & 0x3ff;
+      c32 += 0x10000;
     }
 
     if (c32 >= 0x10000) {
@@ -497,7 +498,7 @@ to_quoted_string (const std::string &s)
       r += "\\r";
     } else if (*c == '\t') {
       r += "\\t";
-    } else if (! isprint (*c)) {
+    } else if (! isprint (*c) || (unsigned char) *c >= 0x80) {
       char b [20];
       ::sprintf (b, "\\%03o", int ((unsigned char) *c));
       r += b;
diff --git a/src/tl/tl/tlThreads.cc b/src/tl/tl/tlThreads.cc
index c0b050a65..7db74573c 100644
--- a/src/tl/tl/tlThreads.cc
+++ b/src/tl/tl/tlThreads.cc
@@ -28,7 +28,11 @@
 
 #include <map>
 #include <pthread.h>
+#include <time.h>
 #include <errno.h>
+#if defined(_WIN32)
+#  include <windows.h>
+#endif
 
 namespace tl
 {
@@ -274,6 +278,23 @@ bool Thread::wait (unsigned long time)
       end_time.tv_sec += 1;
     }
 
+#if defined(_WIN32)
+
+    //  wait if the thread terminated or the timeout has expired
+    while (isRunning ()) {
+
+      struct timespec current_time;
+      clock_gettime (CLOCK_REALTIME, &current_time);
+      if (end_time.tv_sec < current_time.tv_sec || (end_time.tv_sec == current_time.tv_sec && end_time.tv_nsec < current_time.tv_nsec)) {
+        return false;
+      }
+
+      Sleep (1);
+
+    }
+
+#else
+
     int res = pthread_timedjoin_np (mp_data->pthread, &mp_data->return_code, &end_time);
     if (res == ETIMEDOUT) {
       return false;
@@ -281,6 +302,8 @@ bool Thread::wait (unsigned long time)
       tl::error << tr ("Could not join threads");
     }
 
+#endif
+
     return true;
 
   } else {
diff --git a/src/tl/unit_tests/tlExpression.cc b/src/tl/unit_tests/tlExpression.cc
index 9ef0cd556..178fee5f5 100644
--- a/src/tl/unit_tests/tlExpression.cc
+++ b/src/tl/unit_tests/tlExpression.cc
@@ -839,7 +839,11 @@ TEST(6)
   v = e.parse ("absolute_file_path('./x.gds')").execute ();
   // EXPECT_EQ (v.to_string (), std::string ()); // not universal
   v = e.parse ("path('../irgendwas/file.tar.gz')").execute ();
+#if defined(_WIN32)
+  EXPECT_EQ (v.to_string (), std::string ("..\\irgendwas"));
+#else
   EXPECT_EQ (v.to_string (), std::string ("../irgendwas"));
+#endif
   v = e.parse ("basename('../irgendwas/file.tar.gz')").execute ();
   EXPECT_EQ (v.to_string (), std::string ("file"));
   v = e.parse ("extension('../irgendwas/file.tar.gz')").execute ();
diff --git a/src/tl/unit_tests/tlThreads.cc b/src/tl/unit_tests/tlThreads.cc
index 5e41bb48d..fcbbddcfa 100644
--- a/src/tl/unit_tests/tlThreads.cc
+++ b/src/tl/unit_tests/tlThreads.cc
@@ -138,6 +138,10 @@ TEST(1_timed_wait)
 }
 
 int s_mythread2_increment = 1;
+void inc (volatile int &value)
+{
+  value += s_mythread2_increment;
+}
 
 class MyThread2 : public tl::Thread
 {
@@ -155,11 +159,11 @@ public:
       for (int i = 0; i < 10000000; ++i) {
         tl::MutexLocker locker (&m_lock);
         //  Do it more elaborate than ++m_value to prevent compiler optimization
-        m_value += s_mythread2_increment;
+        inc (m_value);
       }
     } else {
       for (int i = 0; i < 10000000; ++i) {
-        m_value += s_mythread2_increment;
+        inc (m_value);
       }
     }
   }
diff --git a/src/unit_tests/unit_test_main.cc b/src/unit_tests/unit_test_main.cc
index 578950ad4..cf619fcf9 100644
--- a/src/unit_tests/unit_test_main.cc
+++ b/src/unit_tests/unit_test_main.cc
@@ -61,8 +61,10 @@
 #  include <Windows.h>
 #endif
 
-//  required to force linking of the "ext", "lib" and "drc" module
+//  required to force linking of the "rdb", "lib" and "drc" module 
+//  (some in non-Qt case)
 #include "libForceLink.h"
+#include "rdbForceLink.h"
 #if defined(HAVE_RUBY) && defined(HAVE_QT)
 #include "drcForceLink.h"
 #endif
diff --git a/src/unit_tests/unit_tests.pro b/src/unit_tests/unit_tests.pro
index d2aa3e207..648d1ec65 100644
--- a/src/unit_tests/unit_tests.pro
+++ b/src/unit_tests/unit_tests.pro
@@ -26,12 +26,17 @@ HEADERS += \
 
 LIBS += -lklayout_gsi_test
 
-INCLUDEPATH += $$QTBASIC_INC
-DEPENDPATH += $$QTBASIC_INC
+!equals(HAVE_QT, "0") {
 
-equals(HAVE_QTBINDINGS, "1") {
-  LIBS += -lklayout_qtbasic -lklayout_QtGui -lklayout_QtXml
-  equals(HAVE_QT5, "1") {
-    LIBS += -lklayout_QtWidgets
+  INCLUDEPATH += $$QTBASIC_INC
+  DEPENDPATH += $$QTBASIC_INC
+
+  equals(HAVE_QTBINDINGS, "1") {
+    LIBS += -lklayout_QtXml
+    equals(HAVE_QT5, "1") {
+      LIBS += -lklayout_QtWidgets
+    }
   }
+
 }
+
diff --git a/src/with_all_libs.pri b/src/with_all_libs.pri
index b4f316b1d..9402fc851 100644
--- a/src/with_all_libs.pri
+++ b/src/with_all_libs.pri
@@ -16,10 +16,10 @@ LIBS += $$PYTHONLIBFILE $$RUBYLIBFILE -L$$DESTDIR -lklayout_tl -lklayout_gsi -lk
   INCLUDEPATH += $$DESTDIR/laybasic $$DESTDIR/lay $$DESTDIR/ext
   DEPENDPATH += $$DESTDIR/laybasic $$DESTDIR/lay $$DESTDIR/ext
 
-}
+  equals(HAVE_QTBINDINGS, "1") {
+    LIBS += -lklayout_qtbasic -lklayout_QtGui -lklayout_QtCore
+  }
 
-equals(HAVE_QTBINDINGS, "1") {
-  LIBS += -lklayout_qtbasic -lklayout_QtGui -lklayout_QtCore
 }
 
 equals(HAVE_RUBY, "1") {
diff --git a/testdata/ruby/layTechnologies.rb b/testdata/ruby/layTechnologies.rb
index 8422b7b7f..91506bc15 100644
--- a/testdata/ruby/layTechnologies.rb
+++ b/testdata/ruby/layTechnologies.rb
@@ -89,17 +89,17 @@ END
     assert_equal(tech.default_base_path, "/default/path")
     assert_equal(tech.base_path, "/default/path")
     assert_equal(tech.correct_path("/default/path/myfile.xml"), "myfile.xml")
-    assert_equal(tech.eff_path("myfile.xml"), "/default/path/myfile.xml")
+    assert_equal(tech.eff_path("myfile.xml").gsub("\\", "/"), "/default/path/myfile.xml")
 
     tech.explicit_base_path = "/basic/path"
     assert_equal(tech.explicit_base_path, "/basic/path")
     assert_equal(tech.base_path, "/basic/path")
     assert_equal(tech.correct_path("/basic/path/myfile.xml"), "myfile.xml")
-    assert_equal(tech.eff_path("myfile.xml"), "/basic/path/myfile.xml")
+    assert_equal(tech.eff_path("myfile.xml").gsub("\\", "/"), "/basic/path/myfile.xml")
 
     tech.layer_properties_file = "x.lyp"
     assert_equal(tech.layer_properties_file, "x.lyp")
-    assert_equal(tech.eff_layer_properties_file, "/basic/path/x.lyp")
+    assert_equal(tech.eff_layer_properties_file.gsub("\\", "/"), "/basic/path/x.lyp")
 
     tech.add_other_layers = true
     assert_equal(tech.add_other_layers?, true)