fix: SLIC3R_PCH=OFF now builds on Windows, allowing compiler caching (#15552)

src/slic3r/CMakeLists.txt

@@ -916,6 +916,9 @@ endif ()
 
 if (SLIC3R_PCH AND NOT SLIC3R_SYNTAXONLY)
     add_precompiled_header(libslic3r_gui pchheader.hpp FORCEINCLUDE)
+elseif (MSVC)
+    # Puts the Windows headers first when the PCH is off.
+    target_compile_options(libslic3r_gui PRIVATE "/FIslic3r/win_platform.hpp")
 endif ()
 
 if (APPLE)

src/slic3r/GUI/DragCanvas.hpp

@@ -3,6 +3,7 @@
 
 #include "wx/bitmap.h"
 #include "wx/dragimag.h"
+#include "wx/panel.h"
 
 namespace Slic3r { namespace GUI {
 

src/slic3r/GUI/GUI_App.cpp

@@ -12,6 +12,7 @@
 #include "BuildCommit.hpp"
 #include "Downloader.hpp"
 #include <boost/chrono/duration.hpp>
+#include <boost/locale/encoding_utf.hpp>
 #include <boost/log/detail/native_typeof.hpp>
 #include <libslic3r/Config.hpp>
 #include <mutex>

src/slic3r/GUI/OptionsGroup.hpp

@@ -199,7 +199,7 @@ public:
 
 	OptionsGroup(wxWindow *_parent, const wxString &title, const wxString &icon, bool is_tab_opt = false,
                     column_t extra_clmn = nullptr);
-	~OptionsGroup() { clear(true); }
+	virtual ~OptionsGroup() { clear(true); }
 
     wxGridSizer*        get_grid_sizer() { return m_grid_sizer; }
 	const std::vector<Line>& get_lines() { return m_lines; }

src/slic3r/GUI/wxMediaCtrl3.h

@@ -8,6 +8,9 @@
 #ifndef wxMediaCtrl3_h
 #define wxMediaCtrl3_h
 
+#include <chrono>
+#include "wx/window.h"
+#include "wx/bitmap.h"
 #include "wx/uri.h"
 #include "wx/mediactrl.h"
 

src/slic3r/Utils/Bonjour.hpp

@@ -115,6 +115,7 @@ class UdpSession
 {
 public:
 	UdpSession(Bonjour::ReplyFn rfn);
+	virtual ~UdpSession() = default;
 	virtual void handle_receive(const boost::system::error_code& error, size_t bytes) = 0;
 	std::vector<char>				buffer;
 	boost::asio::ip::udp::endpoint	remote_endpoint;

src/slic3r/win_platform.hpp

@@ -0,0 +1,19 @@
+#pragma once
+
+// Force-included into libslic3r_gui when SLIC3R_PCH is OFF, standing in for
+// pchheader.hpp, which includes <Windows.h> before anything else. Arriving
+// late and transitively, rpcndr.h defines a global `byte` that collides with
+// std::byte under `using namespace std`, and the control and URL moniker
+// types the GUI uses are never declared.
+#ifdef _WIN32
+    #ifndef WIN32_LEAN_AND_MEAN
+        #define WIN32_LEAN_AND_MEAN
+    #endif
+    #ifndef NOMINMAX
+        #define NOMINMAX
+    #endif
+    #include <Windows.h>
+    #include <CommCtrl.h>
+    #include <urlmon.h>
+#endif // _WIN32
+