Windows 11 Qt 5.15.x 源码编译，支持C++20

configure -debug-and-release -confirm-license -opensource -platform win32-msvc -prefix "G:\\Qt-Build-5.15.17" -qt-sqlite -qt-pcre -qt-zlib -qt-libpng -qt-libjpeg -qt-freetype -qt-harfbuzz -opengl dynamic -skip qtwebengine -nomake tests -no-compile-examples

set CL=/MP #开启多线程编译
nmake # -j8
nmake install

​

​

​

​4.修改源码

直接编译源码无法编译通过，需要改对源码进行修改，参考：

本版本库的一些备注 :: Fsu0413 的原版 Qt 构建 关于mingw部分

--- qtbase\qmake\Makefile.unix.win32	2024-11-20 21:56:33.000000000 +0800
+++ qtbase\qmake\Makefile.unix.win32	2025-07-24 22:47:07.000000000 +0800
@@ -1,8 +1,8 @@EXEEXT = .exe
-EXTRA_CXXFLAGS = -DUNICODE -DMINGW_HAS_SECURE_API=1
+EXTRA_CXXFLAGS = -DUNICODE -DMINGW_HAS_SECURE_API=1 -DWINVER=0x0601 -D_WIN32_WINNT=0x0601EXTRA_LFLAGS = -static -s -lole32 -luuid -ladvapi32 -lkernel32 -lnetapi32QTOBJS = \qfilesystemengine_win.o \qfilesystemiterator_win.o \qfsfileengine_win.o \qlocale_win.o \------------------------------------------------------------------------------------------------
--- qtbase\src\plugins\platforms\windows\windows.pri	2024-11-20 21:56:33.000000000 +0800
+++ qtbase\src\plugins\platforms\windows\windows.pri	2025-07-25 15:18:27.000000000 +0800
@@ -103,12 +103,13 @@SOURCES += $$PWD/qwindowsdrag.cpp}}qtConfig(tabletevent) {INCLUDEPATH += $$QT_SOURCE_TREE/src/3rdparty/wintab
+	 INCLUDEPATH += $$QT_SOURCE_TREE/src/3rdparty/angle/includeHEADERS += $$PWD/qwindowstabletsupport.hSOURCES += $$PWD/qwindowstabletsupport.cpp}qtConfig(sessionmanager) {SOURCES += $$PWD/qwindowssessionmanager.cpp
------------------------------------------------------------------------------------------------
--- qtdeclarative\features\hlsl_bytecode_header.prf	2024-11-20 21:56:37.000000000 +0800
+++ qtdeclarative\features\hlsl_bytecode_header.prf	2025-07-25 15:47:14.000000000 +0800
@@ -1,10 +1,16 @@
+# This variable is from a patch from Fsu0413. In order not to conflict with Qt defined one we use custom prefix
+#$$(DXSDK_DIR)/Utilities/bin/x64/fxc.exe
+mingw: FSU0413_QTDECLARATIVE_FEATURES_FXC = C:/Program Files (x86)/Windows Kits/10/bin/10.0.26100.0/x64/fxc.exe
+else: FSU0413_QTDECLARATIVE_FEATURES_FXC = fxc.exe
+
+for (SHADER, HLSL_SHADERS) {INPUT = $$eval($${SHADER}.input)fxc_$${SHADER}.input = $$INPUT
-    fxc_$${SHADER}.commands = fxc.exe /nologo /E $$eval($${SHADER}.entry) /T $$eval($${SHADER}.type) /Fh ${QMAKE_FILE_OUT} ${QMAKE_FILE_NAME}
+    fxc_$${SHADER}.commands = $$FSU0413_QTDECLARATIVE_FEATURES_FXC /nologo /E $$eval($${SHADER}.entry) /T $$eval($${SHADER}.type) /Fh ${QMAKE_FILE_OUT} ${QMAKE_FILE_NAME}fxc_$${SHADER}.output = $$eval($${SHADER}.header)fxc_$${SHADER}.dependency_type = TYPE_Cfxc_$${SHADER}.variable_out = HEADERSfxc_$${SHADER}.CONFIG += target_predepsQMAKE_EXTRA_COMPILERS += fxc_$${SHADER}}
------------------------------------------------------------------------------------------------
--- qtdeclarative\src\plugins\scenegraph\d3d12\qsgd3d12engine.cpp	2024-11-20 21:56:37.000000000 +0800
+++ qtdeclarative\src\plugins\scenegraph\d3d12\qsgd3d12engine.cpp	2025-07-27 18:38:30.000000000 +0800
@@ -60,12 +60,16 @@#include <windows.ui.xaml.h>#include <windows.ui.xaml.media.dxinterop.h>#endif#include <comdef.h>+#ifdef Q_CC_MINGW
+#include <d3d12sdklayers.h>
+#endif
+QT_BEGIN_NAMESPACE// NOTE: Avoid categorized logging. It is slow.#define DECLARE_DEBUG_VAR(variable) \static bool debug_ ## variable() \
@@ -218,13 +222,13 @@if (qEnvironmentVariableIsSet("QT_D3D_ADAPTER_INDEX")) {const int adapterIndex = qEnvironmentVariableIntValue("QT_D3D_ADAPTER_INDEX");if (SUCCEEDED(factory->EnumAdapters1(adapterIndex, &adapter))) {adapter->GetDesc1(&desc);const QString name = QString::fromUtf16((char16_t *) desc.Description);
-            HRESULT hr = D3D12CreateDevice(adapter.Get(), fl, _uuidof(ID3D12Device), nullptr);
+            HRESULT hr = D3D12CreateDevice(adapter.Get(), fl, __uuidof(ID3D12Device), nullptr);if (SUCCEEDED(hr)) {qCDebug(QSG_LOG_INFO_GENERAL, "Using requested adapter '%s'", qPrintable(name));*outAdapter = adapter.Detach();return;} else {qWarning("Failed to create device for requested adapter '%s': %s",
@@ -235,13 +239,13 @@for (int adapterIndex = 0; factory->EnumAdapters1(adapterIndex, &adapter) != DXGI_ERROR_NOT_FOUND; ++adapterIndex) {adapter->GetDesc1(&desc);if (desc.Flags & DXGI_ADAPTER_FLAG_SOFTWARE)continue;-        if (SUCCEEDED(D3D12CreateDevice(adapter.Get(), fl, _uuidof(ID3D12Device), nullptr))) {
+        if (SUCCEEDED(D3D12CreateDevice(adapter.Get(), fl, __uuidof(ID3D12Device), nullptr))) {const QString name = QString::fromUtf16((char16_t *) desc.Description);qCDebug(QSG_LOG_INFO_GENERAL, "Using adapter '%s'", qPrintable(name));break;}}@@ -714,13 +718,14 @@deviceManager()->unref();initialized = false;// 'window' must be kept, may just be a device loss}
-
+const int QSGD3D12EnginePrivate::MAX_SWAP_CHAIN_BUFFER_COUNT;
+const int QSGD3D12EnginePrivate::MAX_FRAME_IN_FLIGHT_COUNT;void QSGD3D12EnginePrivate::initialize(WId w, const QSize &size, float dpr, int surfaceFormatSamples, bool alpha){if (initialized)return;window = w;--------------------其他修改，跟编译报错无关----------------------------------------------------------------------------
diff -r qtbase\src\widgets\dialogs\qfiledialog_p.h qtbase\src\widgets\dialogs\qfiledialog_p.h
99c99
< struct QFileDialogArgs
---
> struct Q_WIDGETS_EXPORT QFileDialogArgs

注：“C:/Program Files (x86)/Windows Kits/10/bin/10.0.26100.0/x64/fxc.exe” 为 实际 fxc 程序路径