3 files changed, 19 insertions, 2 deletions
diff --git a/src/corelib/io/qprocess_win.cpp b/src/corelib/io/qprocess_win.cpp
index 05c9d6594c..fa9efcb1ce 100644
--- a/src/corelib/io/qprocess_win.cpp
+++ b/src/corelib/io/qprocess_win.cpp
@@ -102,7 +102,7 @@ static void qt_create_pipe(Q_PIPE *pipe, bool isInputPipe)
         // ### The user must make sure to call qsrand() to make the pipe names less predictable.
         // ### Replace the call to qrand() with a secure version, once we have it in Qt.
         _snwprintf(pipeName, sizeof(pipeName) / sizeof(pipeName[0]),
-                L"\\\\.\\pipe\\qt-%X", qrand());
+                L"\\\\.\\pipe\\qt-%lX-%X", long(QCoreApplication::applicationPid()), qrand());
 
         DWORD dwOpenMode = FILE_FLAG_OVERLAPPED;
         DWORD dwOutputBufferSize = 0;
diff --git a/src/plugins/platformthemes/gtk3/qgtk3theme.cpp b/src/plugins/platformthemes/gtk3/qgtk3theme.cpp
index 6447776f25..077955eb4e 100644
--- a/src/plugins/platformthemes/gtk3/qgtk3theme.cpp
+++ b/src/plugins/platformthemes/gtk3/qgtk3theme.cpp
@@ -153,7 +153,7 @@ bool QGtk3Theme::usePlatformNativeDialog(DialogType type) const
     case ColorDialog:
         return true;
     case FileDialog:
-        return true;
+        return useNativeFileDialog();
     case FontDialog:
         return true;
     default:
@@ -167,6 +167,8 @@ QPlatformDialogHelper *QGtk3Theme::createPlatformDialogHelper(DialogType type) c
     case ColorDialog:
         return new QGtk3ColorDialogHelper;
     case FileDialog:
+        if (!useNativeFileDialog())
+            return nullptr;
         return new QGtk3FileDialogHelper;
     case FontDialog:
         return new QGtk3FontDialogHelper;
@@ -185,4 +187,17 @@ QPlatformMenuItem* QGtk3Theme::createPlatformMenuItem() const
     return new QGtk3MenuItem;
 }
 
+bool QGtk3Theme::useNativeFileDialog()
+{
+    /* Require GTK3 >= 3.15.5 to avoid running into this bug:
+     * https://bugzilla.gnome.org/show_bug.cgi?id=725164
+     *
+     * While this bug only occurs when using widget-based file dialogs
+     * (native GTK3 dialogs are fine) we have to disable platform file
+     * dialogs entirely since we can't avoid creation of a platform
+     * dialog helper.
+     */
+    return gtk_check_version(3, 15, 5) == 0;
+}
+
 QT_END_NAMESPACE
diff --git a/src/plugins/platformthemes/gtk3/qgtk3theme.h b/src/plugins/platformthemes/gtk3/qgtk3theme.h
index 52036680c6..abc5dbfd17 100644
--- a/src/plugins/platformthemes/gtk3/qgtk3theme.h
+++ b/src/plugins/platformthemes/gtk3/qgtk3theme.h
@@ -59,6 +59,8 @@ public:
     QPlatformMenuItem* createPlatformMenuItem() const Q_DECL_OVERRIDE;
 
     static const char *name;
+private:
+    static bool useNativeFileDialog();
 };
 
 QT_END_NAMESPACE