Fix compilation under Windows with GUI and LLVM enabled. * configure.ac (OCTGUI_DLL_DEFS): New substituted variabled. Define it to -DOCTGUI_DLL under MinGW and MSVC platforms. (QT_INCDIR, QT_LIBDIR): Replace backslash with forward slash characters. (OCTGUI_API): New config.h macro. * src/Makefile.am (MOC_CPPFLAGS): New variable. Define it to -DWIN32 when compiling Win32 terminal implementation. (moc-%.cc rule): Use it. (libqterminal_la_CPPFLAGS): New variable defined to -DWIN32 when compiling the win32 terminal implementation. (liboctgui_la_CPPFLAGS): Add @OCTGUI_DLL_DEFS@. * libgui/src/m-editor/file-editor-tab.cc (QApplication, QFileDialog, QTextStream): New includes. * libgui/src/m-editor/find-dialog.cc (find_dialog::search_next): Temporary fix for compilation with QScintilla < 2.6. * libgui/src/main-window.cc (QApplication, QLabel): New includes. * libgui/src/octave-gui.h (octave_start_gui): Decorate with OCTGUI_API.

--- a/libgui/src/main-window.cc
+++ b/libgui/src/main-window.cc
@@ -20,6 +20,8 @@
 
 */
 
+#include <QApplication>
+#include <QLabel>
 #include <QMenuBar>
 #include <QMenu>
 #include <QAction>