A few mingw related fixes

Signed-off-by: falkTX <falktx@falktx.com>

.gitmodules

@@ -4,3 +4,6 @@
 [submodule "dpf"]
 	path = dpf
 	url = https://github.com/DISTRHO/DPF.git
+[submodule "plugins/CVCRack/mingw-std-threads"]
+	path = plugins/CVCRack/mingw-std-threads
+	url = https://github.com/meganz/mingw-std-threads.git

plugins/CVCRack/Makefile

@@ -52,6 +52,7 @@ FILES_DSP += $(wildcard Rack/src/*/*.cpp)
 EXTRA_LIBS += Rack/dep/lib/libglfw3.a
 EXTRA_LIBS += Rack/dep/lib/libjansson.a
 EXTRA_LIBS += Rack/dep/lib/libspeexdsp.a
+EXTRA_LIBS += Rack/dep/lib/libzstd.a
 
 ifeq ($(WINDOWS),true)
 EXTRA_LIBS += Rack/dep/lib/libarchive_static.a
@@ -90,6 +91,11 @@ BASE_FLAGS += -IRack/dep/osdialog
 BASE_FLAGS += -IRack/dep/oui-blendish
 BASE_FLAGS += -IRack/dep/pffft
 
+ifeq ($(WINDOWS),true)
+BASE_FLAGS      += -Imingw-compat
+BUILD_CXX_FLAGS += -Imingw-std-threads
+endif
+
 ifeq ($(MACOS),true)
 BASE_FLAGS += -DARCH_MAC
 else ifeq ($(WINDOWS),true)

plugins/CVCRack/mingw-compat/Shlobj.h

@@ -0,0 +1 @@
+#include <shlobj.h>

plugins/CVCRack/mingw-compat/Shlwapi.h

@@ -0,0 +1 @@
+#include <shlwapi.h>

plugins/CVCRack/mingw-compat/Windows.h

@@ -0,0 +1 @@
+#include <windows.h>

plugins/CVCRack/mingw-compat/condition_variable

@@ -0,0 +1,3 @@
+#pragma once
+#include_next <condition_variable>
+#include "mingw.condition_variable.h"

plugins/CVCRack/mingw-compat/mutex

@@ -0,0 +1,3 @@
+#pragma once
+#include_next <mutex>
+#include "mingw.mutex.h"

plugins/CVCRack/mingw-compat/thread

@@ -0,0 +1,3 @@
+#pragma once
+#include_next <thread>
+#include "mingw.thread.h"

plugins/CVCRack/mingw-std-threads

@@ -0,0 +1 @@
+Subproject commit f6365f900fb9b1cd6014c8d1cf13ceacf8faf3de