Upgrade to C++20 (#7554)

* Compile in C++20 mode * Fix implicit lambda captures of `this` by `[=]` Those implicit captures were deprecated in C++20 * Silence MSVC atomic std::shared_ptr warning Unfortunately std::atomic<std::shared_ptr> (P0718R2) is not supported by GCC until GCC 12 and still is not supported by Clang or Apple Clang, so it looks like we will continue using std::atomic_load for the time being * Use C++20 in RemoteVstPlugin * Simplification * Add comment * Fix bitwise operations between different enumeration types * Revert "Fix bitwise operations between different enumeration types" This reverts commit d45792cd72. * Use a helper function to combine keys and modifiers * Remove AnalyzeTemporaryDtors from .clang-tidy AnalyzeTemporaryDtors was deprecated in clang-tidy 16 and fully removed in clang-tidy 18 * Use C++20 in .clang-format * Use bitwise OR Prevents issues if any enum flags in `args` have bits in common
2024-11-22 23:11:39 -05:00
parent 72b30b1d00
commit c21a7cd487
23 changed files with 109 additions and 73 deletions
--- a/.clang-format
+++ b/.clang-format
@@ -1,7 +1,7 @@
 ---
 # Language
 Language:        Cpp
-Standard:        Cpp11  # Cpp14 and Cpp17 are not supported by clang 11
+Standard:        c++20

 # Indentation
 TabWidth:        4
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -20,7 +20,6 @@ Checks: >
  readability-simplify-boolean-expr
 WarningsAsErrors: ''
 HeaderFilterRegex: '' # don't show errors from headers
-AnalyzeTemporaryDtors: false
 FormatStyle:     none
 User:            user
 CheckOptions:    
--- a/cmake/modules/ErrorFlags.cmake
+++ b/cmake/modules/ErrorFlags.cmake
@@ -65,6 +65,10 @@ elseif(MSVC)
 			"/WX" # Treat warnings as errors
 		)
 	endif()
+
+	# Silence deprecation warnings for the std::atomic_...<std::shared_ptr> family of functions.
+	# TODO: Remove once C++20's std::atomic<std::shared_ptr> is fully supported.
+	add_compile_definitions("_SILENCE_CXX20_OLD_SHARED_PTR_ATOMIC_SUPPORT_DEPRECATION_WARNING")
 endif()

 # Add the flags to the whole directory tree. We use the third-party flags for
--- a/include/DeprecationHelper.h
+++ b/include/DeprecationHelper.h
@@ -27,7 +27,10 @@
 #ifndef LMMS_DEPRECATIONHELPER_H
 #define LMMS_DEPRECATIONHELPER_H

+#include <type_traits>
+
 #include <QFontMetrics>
+#include <QKeySequence>
 #include <QWheelEvent>

 namespace lmms
@@ -64,6 +67,30 @@ inline QPoint position(QWheelEvent *wheelEvent)
 #endif
 }

+
+namespace detail
+{
+
+template<typename T>
+inline constexpr bool IsKeyOrModifier = std::is_same_v<T, Qt::Key>
+	|| std::is_same_v<T, Qt::Modifier> || std::is_same_v<T, Qt::KeyboardModifier>;
+
+} // namespace detail
+
+
+/**
+ * @brief Combines Qt key and modifier arguments together,
+ * replacing `A | B` which was deprecated in C++20
+ * due to the enums being different types. (P1120R0)
+ * @param args Any number of Qt::Key, Qt::Modifier, or Qt::KeyboardModifier
+ * @return The combination of the given keys/modifiers as an int
+ */
+template<typename... Args, std::enable_if_t<(detail::IsKeyOrModifier<Args> && ...), bool> = true>
+constexpr int combine(Args... args)
+{
+	return (0 | ... | static_cast<int>(args));
+}
+
 } // namespace lmms

 #endif // LMMS_DEPRECATIONHELPER_H
--- a/plugins/CMakeLists.txt
+++ b/plugins/CMakeLists.txt
@@ -2,8 +2,8 @@ SET(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
 SET(CMAKE_LIBRARY_OUTPUT_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
 SET(CMAKE_DEBUG_POSTFIX "")

-# Enable C++17
-SET(CMAKE_CXX_STANDARD 17)
+# Enable C++20
+SET(CMAKE_CXX_STANDARD 20)

 IF(LMMS_BUILD_APPLE AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")
 	SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
--- a/plugins/SpectrumAnalyzer/SaControlsDialog.cpp
+++ b/plugins/SpectrumAnalyzer/SaControlsDialog.cpp
@@ -341,7 +341,6 @@ SaControlsDialog::SaControlsDialog(SaControls *controls, SaProcessor *processor)
 	m_waterfall = new SaWaterfallView(controls, processor, this);
 	display_splitter->addWidget(m_waterfall);
 	m_waterfall->setVisible(m_controls->m_waterfallModel.value());
-	connect(&controls->m_waterfallModel, &BoolModel::dataChanged, [=] {m_waterfall->updateVisibility();});
 }


--- a/plugins/SpectrumAnalyzer/SaWaterfallView.cpp
+++ b/plugins/SpectrumAnalyzer/SaWaterfallView.cpp
@@ -54,6 +54,7 @@ SaWaterfallView::SaWaterfallView(SaControls *controls, SaProcessor *processor, Q
 	setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);

 	connect(getGUI()->mainWindow(), SIGNAL(periodicUpdate()), this, SLOT(periodicUpdate()));
+	connect(&controls->m_waterfallModel, &BoolModel::dataChanged, this, &SaWaterfallView::updateVisibility);

 	m_displayTop = 1;
 	m_displayBottom = height() -2;
--- a/plugins/Vibed/NineButtonSelector.cpp
+++ b/plugins/Vibed/NineButtonSelector.cpp
@@ -47,7 +47,7 @@ NineButtonSelector::NineButtonSelector(std::array<QPixmap, 18> onOffIcons, int d
 		m_buttons[i]->setActiveGraphic(onOffIcons[i * 2]);
 		m_buttons[i]->setInactiveGraphic(onOffIcons[(i * 2) + 1]);
 		m_buttons[i]->setChecked(false);
-		connect(m_buttons[i].get(), &PixmapButton::clicked, this, [=](){ this->buttonClicked(i); });
+		connect(m_buttons[i].get(), &PixmapButton::clicked, this, [=, this](){ buttonClicked(i); });
 	}

 	m_lastBtn = m_buttons[defaultButton].get();
--- a/plugins/VstBase/RemoteVstPlugin/CMakeLists.txt
+++ b/plugins/VstBase/RemoteVstPlugin/CMakeLists.txt
@@ -6,7 +6,7 @@ endif()

 project(RemoteVstPlugin 
 	LANGUAGES CXX)
-set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD 20)

 include(CheckCXXPreprocessor)
 include(CheckCXXSourceCompiles)
@@ -73,7 +73,7 @@ if(MSVC)
 endif()

 if(IS_MINGW)
-	SET(CMAKE_REQUIRED_FLAGS "-std=c++17")
+	SET(CMAKE_REQUIRED_FLAGS "-std=c++20")
 endif()

 if(LMMS_BUILD_WIN32)
--- a/src/3rdparty/CMakeLists.txt
+++ b/src/3rdparty/CMakeLists.txt
@@ -15,7 +15,7 @@ ADD_SUBDIRECTORY(weakjack)
 add_library(ringbuffer OBJECT
 	ringbuffer/src/lib/ringbuffer.cpp
 )
-target_compile_features(ringbuffer PUBLIC cxx_std_17)
+target_compile_features(ringbuffer PUBLIC cxx_std_20)
 target_include_directories(ringbuffer PUBLIC
 	ringbuffer/include
 	"${CMAKE_CURRENT_BINARY_DIR}"
--- a/src/3rdparty/hiir/CMakeLists.txt
+++ b/src/3rdparty/hiir/CMakeLists.txt
@@ -1,3 +1,3 @@
 add_library(hiir INTERFACE)
 target_include_directories(hiir INTERFACE ${CMAKE_CURRENT_SOURCE_DIR})
-target_compile_features(hiir INTERFACE cxx_std_17)
+target_compile_features(hiir INTERFACE cxx_std_20)
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -9,8 +9,8 @@ SET(CMAKE_AUTOMOC ON)
 SET(CMAKE_AUTOUIC ON)
 SET(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR})

-# Enable C++17
-SET(CMAKE_CXX_STANDARD 17)
+# Enable C++20
+SET(CMAKE_CXX_STANDARD 20)

 IF(LMMS_BUILD_APPLE AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")
 	SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
--- a/src/gui/ControllerRackView.cpp
+++ b/src/gui/ControllerRackView.cpp
@@ -23,6 +23,8 @@
 *
 */

+#include "ControllerRackView.h"
+
 #include <QApplication>
 #include <QAction>
 #include <QPushButton>
@@ -30,13 +32,13 @@
 #include <QMessageBox>
 #include <QVBoxLayout>

-#include "Song.h"
+#include "ControllerView.h"
+#include "DeprecationHelper.h"
 #include "embed.h"
 #include "GuiApplication.h"
-#include "MainWindow.h"
-#include "ControllerRackView.h"
-#include "ControllerView.h"
 #include "LfoController.h"
+#include "MainWindow.h"
+#include "Song.h"
 #include "SubWindow.h"

 namespace lmms::gui
@@ -167,13 +169,13 @@ void ControllerRackView::addController(Controller* controller)
 	connect(controllerView, &ControllerView::removedController, this, &ControllerRackView::deleteController, Qt::QueuedConnection);

 	auto moveUpAction = new QAction(controllerView);
-	moveUpAction->setShortcut(Qt::Key_Up | Qt::AltModifier);
+	moveUpAction->setShortcut(combine(Qt::Key_Up, Qt::AltModifier));
 	moveUpAction->setShortcutContext(Qt::WidgetShortcut);
 	connect(moveUpAction, &QAction::triggered, controllerView, &ControllerView::moveUp);
 	controllerView->addAction(moveUpAction);

 	auto moveDownAction = new QAction(controllerView);
-	moveDownAction->setShortcut(Qt::Key_Down | Qt::AltModifier);
+	moveDownAction->setShortcut(combine(Qt::Key_Down, Qt::AltModifier));
 	moveDownAction->setShortcutContext(Qt::WidgetShortcut);
 	connect(moveDownAction, &QAction::triggered, controllerView, &ControllerView::moveDown);
 	controllerView->addAction(moveDownAction);
--- a/src/gui/EffectRackView.cpp
+++ b/src/gui/EffectRackView.cpp
@@ -23,13 +23,15 @@
 *
 */

+#include "EffectRackView.h"
+
 #include <QApplication>
 #include <QAction>
 #include <QPushButton>
 #include <QScrollArea>
 #include <QVBoxLayout>

-#include "EffectRackView.h"
+#include "DeprecationHelper.h"
 #include "EffectSelectDialog.h"
 #include "EffectView.h"
 #include "GroupBox.h"
@@ -176,13 +178,13 @@ void EffectRackView::update()
 			connect(view, &EffectView::deletedPlugin, this, &EffectRackView::deletePlugin, Qt::QueuedConnection);

 			QAction* moveUpAction = new QAction(view);
-			moveUpAction->setShortcut(Qt::Key_Up | Qt::AltModifier);
+			moveUpAction->setShortcut(combine(Qt::Key_Up, Qt::AltModifier));
 			moveUpAction->setShortcutContext(Qt::WidgetShortcut);
 			connect(moveUpAction, &QAction::triggered, view, &EffectView::moveUp);
 			view->addAction(moveUpAction);

 			QAction* moveDownAction = new QAction(view);
-			moveDownAction->setShortcut(Qt::Key_Down | Qt::AltModifier);
+			moveDownAction->setShortcut(combine(Qt::Key_Down, Qt::AltModifier));
 			moveDownAction->setShortcutContext(Qt::WidgetShortcut);
 			connect(moveDownAction, &QAction::triggered, view, &EffectView::moveDown);
 			view->addAction(moveDownAction);
--- a/src/gui/FileBrowser.cpp
+++ b/src/gui/FileBrowser.cpp
@@ -635,7 +635,7 @@ void FileBrowserTreeWidget::contextMenuEvent(QContextMenuEvent * e )

 		contextMenu.addAction(
 			tr( "Send to active instrument-track" ),
-			[=]{ sendToActiveInstrumentTrack(file); }
+			[=, this]{ sendToActiveInstrumentTrack(file); }
 		);

 		contextMenu.addSeparator();
@@ -643,7 +643,7 @@ void FileBrowserTreeWidget::contextMenuEvent(QContextMenuEvent * e )
 		contextMenu.addAction(
 			QIcon(embed::getIconPixmap("folder")),
 			tr("Open containing folder"),
-			[=]{ openContainingFolder(file); }
+			[=, this]{ openContainingFolder(file); }
 		);

 		auto songEditorHeader = new QAction(tr("Song Editor"), nullptr);
@@ -676,14 +676,14 @@ QList<QAction*> FileBrowserTreeWidget::getContextActions(FileItem* file, bool so

 	auto toInstrument = new QAction(instrumentAction + tr(" (%2Enter)").arg(shortcutMod), nullptr);
 	connect(toInstrument, &QAction::triggered,
-		[=]{ openInNewInstrumentTrack(file, songEditor); });
+		[=, this]{ openInNewInstrumentTrack(file, songEditor); });
 	result.append(toInstrument);

 	if (songEditor && fileIsSample)
 	{
 		auto toSampleTrack = new QAction(tr("Send to new sample track (Shift + Enter)"), nullptr);
 		connect(toSampleTrack, &QAction::triggered,
-			[=]{ openInNewSampleTrack(file); });
+			[=, this]{ openInNewSampleTrack(file); });
 		result.append(toSampleTrack);
 	}

--- a/src/gui/MainWindow.cpp
+++ b/src/gui/MainWindow.cpp
@@ -38,6 +38,7 @@
 #include "AboutDialog.h"
 #include "AutomationEditor.h"
 #include "ControllerRackView.h"
+#include "DeprecationHelper.h"
 #include "embed.h"
 #include "Engine.h"
 #include "ExportProjectDialog.h"
@@ -293,11 +294,11 @@ void MainWindow::finalize()
 	project_menu->addAction( embed::getIconPixmap( "project_save" ),
 					tr( "Save &As..." ),
 					this, SLOT(saveProjectAs()),
-					Qt::CTRL + Qt::SHIFT + Qt::Key_S );
+					combine(Qt::CTRL, Qt::SHIFT, Qt::Key_S));
 	project_menu->addAction( embed::getIconPixmap( "project_save" ),
 					tr( "Save as New &Version" ),
 					this, SLOT(saveProjectAsNewVersion()),
-					Qt::CTRL + Qt::ALT + Qt::Key_S );
+					combine(Qt::CTRL, Qt::ALT, Qt::Key_S));

 	project_menu->addAction( embed::getIconPixmap( "project_save" ),
 					tr( "Save as default template" ),
@@ -312,23 +313,23 @@ void MainWindow::finalize()
 					tr( "E&xport..." ),
 					this,
 					SLOT(onExportProject()),
-					Qt::CTRL + Qt::Key_E );
+					combine(Qt::CTRL, Qt::Key_E));
 	project_menu->addAction( embed::getIconPixmap( "project_export" ),
 					tr( "E&xport Tracks..." ),
 					this,
 					SLOT(onExportProjectTracks()),
-					Qt::CTRL + Qt::SHIFT + Qt::Key_E );
+					combine(Qt::CTRL, Qt::SHIFT, Qt::Key_E));

 	project_menu->addAction( embed::getIconPixmap( "midi_file" ),
 					tr( "Export &MIDI..." ),
 					this,
 					SLOT(onExportProjectMidi()),
-					Qt::CTRL + Qt::Key_M );
+					combine(Qt::CTRL, Qt::Key_M));

 	project_menu->addSeparator();
 	project_menu->addAction( embed::getIconPixmap( "exit" ), tr( "&Quit" ),
 					qApp, SLOT(closeAllWindows()),
-					Qt::CTRL + Qt::Key_Q );
+					combine(Qt::CTRL, Qt::Key_Q));

 	auto edit_menu = new QMenu(this);
 	menuBar()->addMenu( edit_menu )->setText( tr( "&Edit" ) );
@@ -341,13 +342,13 @@ void MainWindow::finalize()
 					this, SLOT(redo()),
 					QKeySequence::Redo );
 	// Ensure that both (Ctrl+Y) and (Ctrl+Shift+Z) activate redo shortcut regardless of OS defaults
-	if (QKeySequence(QKeySequence::Redo) != QKeySequence(Qt::CTRL + Qt::Key_Y))
+	if (QKeySequence(QKeySequence::Redo) != QKeySequence(combine(Qt::CTRL, Qt::Key_Y)))
 	{
-		new QShortcut( QKeySequence( Qt::CTRL + Qt::Key_Y ), this, SLOT(redo()));
+		new QShortcut(QKeySequence(combine(Qt::CTRL, Qt::Key_Y)), this, SLOT(redo()));
 	}
-	if (QKeySequence(QKeySequence::Redo) != QKeySequence(Qt::CTRL + Qt::SHIFT + Qt::Key_Z ))
+	if (QKeySequence(QKeySequence::Redo) != QKeySequence(combine(Qt::CTRL, Qt::SHIFT, Qt::Key_Z)))
 	{
-		new QShortcut( QKeySequence( Qt::CTRL + Qt::SHIFT + Qt::Key_Z ), this, SLOT(redo()));
+		new QShortcut(QKeySequence(combine(Qt::CTRL, Qt::SHIFT, Qt::Key_Z)), this, SLOT(redo()));
 	}

 	edit_menu->addSeparator();
@@ -446,31 +447,31 @@ void MainWindow::finalize()
 	// window-toolbar
 	auto song_editor_window = new ToolButton(embed::getIconPixmap("songeditor"), tr("Song Editor") + " (Ctrl+1)", this,
 		SLOT(toggleSongEditorWin()), m_toolBar);
-	song_editor_window->setShortcut( Qt::CTRL + Qt::Key_1 );
+	song_editor_window->setShortcut(combine(Qt::CTRL, Qt::Key_1));

 	auto pattern_editor_window = new ToolButton(embed::getIconPixmap("pattern_track_btn"),
 		tr("Pattern Editor") + " (Ctrl+2)", this, SLOT(togglePatternEditorWin()), m_toolBar);
-	pattern_editor_window->setShortcut(Qt::CTRL + Qt::Key_2);
+	pattern_editor_window->setShortcut(combine(Qt::CTRL, Qt::Key_2));

 	auto piano_roll_window = new ToolButton(
 		embed::getIconPixmap("piano"), tr("Piano Roll") + " (Ctrl+3)", this, SLOT(togglePianoRollWin()), m_toolBar);
-	piano_roll_window->setShortcut( Qt::CTRL + Qt::Key_3 );
+	piano_roll_window->setShortcut(combine(Qt::CTRL, Qt::Key_3));

 	auto automation_editor_window = new ToolButton(embed::getIconPixmap("automation"),
 		tr("Automation Editor") + " (Ctrl+4)", this, SLOT(toggleAutomationEditorWin()), m_toolBar);
-	automation_editor_window->setShortcut( Qt::CTRL + Qt::Key_4 );
+	automation_editor_window->setShortcut(combine(Qt::CTRL, Qt::Key_4));

 	auto mixer_window = new ToolButton(
 		embed::getIconPixmap("mixer"), tr("Mixer") + " (Ctrl+5)", this, SLOT(toggleMixerWin()), m_toolBar);
-	mixer_window->setShortcut( Qt::CTRL + Qt::Key_5 );
+	mixer_window->setShortcut(combine(Qt::CTRL, Qt::Key_5));

 	auto controllers_window = new ToolButton(embed::getIconPixmap("controller"),
 		tr("Show/hide controller rack") + " (Ctrl+6)", this, SLOT(toggleControllerRack()), m_toolBar);
-	controllers_window->setShortcut( Qt::CTRL + Qt::Key_6 );
+	controllers_window->setShortcut(combine(Qt::CTRL, Qt::Key_6));

 	auto project_notes_window = new ToolButton(embed::getIconPixmap("project_notes"),
 		tr("Show/hide project notes") + " (Ctrl+7)", this, SLOT(toggleProjectNotesWin()), m_toolBar);
-	project_notes_window->setShortcut( Qt::CTRL + Qt::Key_7 );
+	project_notes_window->setShortcut(combine(Qt::CTRL, Qt::Key_7));

 	m_toolBarLayout->addWidget( song_editor_window, 1, 1 );
 	m_toolBarLayout->addWidget( pattern_editor_window, 1, 2 );
--- a/src/gui/MicrotunerConfig.cpp
+++ b/src/gui/MicrotunerConfig.cpp
@@ -94,7 +94,7 @@ MicrotunerConfig::MicrotunerConfig() :
 	auto scaleCombo = new ComboBox();
 	scaleCombo->setModel(&m_scaleComboModel);
 	microtunerLayout->addWidget(scaleCombo, 1, 0, 1, 2);
-	connect(&m_scaleComboModel, &ComboBoxModel::dataChanged, [=] {updateScaleForm();});
+	connect(&m_scaleComboModel, &ComboBoxModel::dataChanged, this, &MicrotunerConfig::updateScaleForm);

 	m_scaleNameEdit = new QLineEdit("12-TET");
 	m_scaleNameEdit->setToolTip(tr("Scale description. Cannot start with \"!\" and cannot contain a newline character."));
@@ -106,8 +106,8 @@ MicrotunerConfig::MicrotunerConfig() :
 	saveScaleButton->setToolTip(tr("Save scale definition to a file."));
 	microtunerLayout->addWidget(loadScaleButton, 3, 0, 1, 1);
 	microtunerLayout->addWidget(saveScaleButton, 3, 1, 1, 1);
-	connect(loadScaleButton, &QPushButton::clicked, [=] {loadScaleFromFile();});
-	connect(saveScaleButton, &QPushButton::clicked, [=] {saveScaleToFile();});
+	connect(loadScaleButton, &QPushButton::clicked, this, &MicrotunerConfig::loadScaleFromFile);
+	connect(saveScaleButton, &QPushButton::clicked, this, &MicrotunerConfig::saveScaleToFile);

 	m_scaleTextEdit = new QPlainTextEdit();
 	m_scaleTextEdit->setPlainText("100.0\n200.0\n300.0\n400.0\n500.0\n600.0\n700.0\n800.0\n900.0\n1000.0\n1100.0\n1200.0");
@@ -117,7 +117,7 @@ MicrotunerConfig::MicrotunerConfig() :
 	auto applyScaleButton = new QPushButton(tr("Apply scale changes"));
 	applyScaleButton->setToolTip(tr("Verify and apply changes made to the selected scale. To use the scale, select it in the settings of a supported instrument."));
 	microtunerLayout->addWidget(applyScaleButton, 6, 0, 1, 2);
-	connect(applyScaleButton, &QPushButton::clicked, [=] {applyScale();});
+	connect(applyScaleButton, &QPushButton::clicked, this, &MicrotunerConfig::applyScale);

 	// ----------------------------------
 	// Mapping sub-column
@@ -132,7 +132,7 @@ MicrotunerConfig::MicrotunerConfig() :
 	auto keymapCombo = new ComboBox();
 	keymapCombo->setModel(&m_keymapComboModel);
 	microtunerLayout->addWidget(keymapCombo, 1, 2, 1, 2);
-	connect(&m_keymapComboModel, &ComboBoxModel::dataChanged, [=] {updateKeymapForm();});
+	connect(&m_keymapComboModel, &ComboBoxModel::dataChanged, this, &MicrotunerConfig::updateKeymapForm);

 	m_keymapNameEdit = new QLineEdit("default");
 	m_keymapNameEdit->setToolTip(tr("Keymap description. Cannot start with \"!\" and cannot contain a newline character."));
@@ -144,8 +144,8 @@ MicrotunerConfig::MicrotunerConfig() :
 	saveKeymapButton->setToolTip(tr("Save key mapping definition to a file."));
 	microtunerLayout->addWidget(loadKeymapButton, 3, 2, 1, 1);
 	microtunerLayout->addWidget(saveKeymapButton, 3, 3, 1, 1);
-	connect(loadKeymapButton, &QPushButton::clicked, [=] {loadKeymapFromFile();});
-	connect(saveKeymapButton, &QPushButton::clicked, [=] {saveKeymapToFile();});
+	connect(loadKeymapButton, &QPushButton::clicked, this, &MicrotunerConfig::loadKeymapFromFile);
+	connect(saveKeymapButton, &QPushButton::clicked, this, &MicrotunerConfig::saveKeymapToFile);

 	m_keymapTextEdit = new QPlainTextEdit();
 	m_keymapTextEdit->setPlainText("0\n1\n2\n3\n4\n5\n6\n7\n8\n9\n10\n11");
@@ -189,7 +189,7 @@ MicrotunerConfig::MicrotunerConfig() :
 	auto applyKeymapButton = new QPushButton(tr("Apply keymap changes"));
 	applyKeymapButton->setToolTip(tr("Verify and apply changes made to the selected key mapping. To use the mapping, select it in the settings of a supported instrument."));
 	microtunerLayout->addWidget(applyKeymapButton, 6, 2, 1, 2);
-	connect(applyKeymapButton, &QPushButton::clicked, [=] {applyKeymap();});
+	connect(applyKeymapButton, &QPushButton::clicked, this, &MicrotunerConfig::applyKeymap);

 	updateScaleForm();
 	updateKeymapForm();
@@ -325,7 +325,7 @@ void MicrotunerConfig::updateKeymapForm()
 */
 bool MicrotunerConfig::validateScaleForm()
 {
-	auto fail = [=](QString message) {QMessageBox::critical(this, tr("Scale parsing error"), message);};
+	auto fail = [this](const QString& message){ QMessageBox::critical(this, tr("Scale parsing error"), message); };

 	// check name
 	QString name = m_scaleNameEdit->text();
@@ -373,7 +373,7 @@ bool MicrotunerConfig::validateScaleForm()
 */
 bool MicrotunerConfig::validateKeymapForm()
 {
-	auto fail = [=](QString message) {QMessageBox::critical(this, tr("Keymap parsing error"), message);};
+	auto fail = [this](const QString& message){ QMessageBox::critical(this, tr("Keymap parsing error"), message); };

 	// check name
 	QString name = m_keymapNameEdit->text();
--- a/src/gui/PluginBrowser.cpp
+++ b/src/gui/PluginBrowser.cpp
@@ -297,7 +297,7 @@ void PluginDescWidget::contextMenuEvent(QContextMenuEvent* e)
 	QMenu contextMenu(this);
 	contextMenu.addAction(
 		tr("Send to new instrument track"),
-		[=]{ openInNewInstrumentTrack(m_pluginKey.desc->name); }
+		[=, this]{ openInNewInstrumentTrack(m_pluginKey.desc->name); }
 	);
 	contextMenu.exec(e->globalPos());
 }
--- a/src/gui/SideBarWidget.cpp
+++ b/src/gui/SideBarWidget.cpp
@@ -50,7 +50,7 @@ SideBarWidget::SideBarWidget( const QString & _title, const QPixmap & _icon,
 	m_closeBtn->resize(m_buttonSize);
 	m_closeBtn->setToolTip(tr("Close"));
 	connect(m_closeBtn, &QPushButton::clicked,
-		[=]() { this->closeButtonClicked(); });
+		[this]() { this->closeButtonClicked(); });
 }


--- a/src/gui/editors/AutomationEditor.cpp
+++ b/src/gui/editors/AutomationEditor.cpp
@@ -2037,17 +2037,17 @@ AutomationEditorWindow::AutomationEditorWindow() :

 	auto editModeGroup = new ActionGroup(this);
 	m_drawAction = editModeGroup->addAction(embed::getIconPixmap("edit_draw"), tr("Draw mode (Shift+D)"));
-	m_drawAction->setShortcut(Qt::SHIFT | Qt::Key_D);
+	m_drawAction->setShortcut(combine(Qt::SHIFT, Qt::Key_D));
 	m_drawAction->setChecked(true);

 	m_eraseAction = editModeGroup->addAction(embed::getIconPixmap("edit_erase"), tr("Erase mode (Shift+E)"));
-	m_eraseAction->setShortcut(Qt::SHIFT | Qt::Key_E);
+	m_eraseAction->setShortcut(combine(Qt::SHIFT, Qt::Key_E));

 	m_drawOutAction = editModeGroup->addAction(embed::getIconPixmap("edit_draw_outvalue"), tr("Draw outValues mode (Shift+C)"));
-	m_drawOutAction->setShortcut(Qt::SHIFT | Qt::Key_C);
+	m_drawOutAction->setShortcut(combine(Qt::SHIFT, Qt::Key_C));

 	m_editTanAction = editModeGroup->addAction(embed::getIconPixmap("edit_tangent"), tr("Edit tangents mode (Shift+T)"));
-	m_editTanAction->setShortcut(Qt::SHIFT | Qt::Key_T);
+	m_editTanAction->setShortcut(combine(Qt::SHIFT, Qt::Key_T));
 	m_editTanAction->setEnabled(false);

 	m_flipYAction = new QAction(embed::getIconPixmap("flip_y"), tr("Flip vertically"), this);
--- a/src/gui/editors/Editor.cpp
+++ b/src/gui/editors/Editor.cpp
@@ -24,6 +24,7 @@

 #include "Editor.h"

+#include "DeprecationHelper.h"
 #include "GuiApplication.h"
 #include "MainWindow.h"
 #include "Song.h"
@@ -118,8 +119,8 @@ Editor::Editor(bool record, bool stepRecord) :
 	connect(m_toggleStepRecordingAction, SIGNAL(triggered()), this, SLOT(toggleStepRecording()));
 	connect(m_stopAction, SIGNAL(triggered()), this, SLOT(stop()));
 	new QShortcut(Qt::Key_Space, this, SLOT(togglePlayStop()));
-	new QShortcut(QKeySequence(Qt::SHIFT + Qt::Key_Space), this, SLOT(togglePause()));
-	new QShortcut(QKeySequence(Qt::SHIFT + Qt::Key_F11), this, SLOT(toggleMaximize()));
+	new QShortcut(QKeySequence(combine(Qt::SHIFT, Qt::Key_Space)), this, SLOT(togglePause()));
+	new QShortcut(QKeySequence(combine(Qt::SHIFT, Qt::Key_F11)), this, SLOT(toggleMaximize()));

 	// Add actions to toolbar
 	addButton(m_playAction, "playButton");
--- a/src/gui/editors/PianoRoll.cpp
+++ b/src/gui/editors/PianoRoll.cpp
@@ -3098,7 +3098,7 @@ void PianoRoll::paintEvent(QPaintEvent * pe )
 			// allow quantization grid up to 1/32 for normal notes
 			else if (q < 6) { q = 6; }
 		}
-		auto xCoordOfTick = [=](int tick) {
+		auto xCoordOfTick = [this](int tick) {
 			return m_whiteKeyWidth + (
 				(tick - m_currentPosition) * m_ppb / TimePos::ticksPerBar()
 			);
@@ -4764,10 +4764,10 @@ PianoRollWindow::PianoRollWindow() :

 	drawAction->setChecked( true );

-	drawAction->setShortcut( Qt::SHIFT | Qt::Key_D );
-	eraseAction->setShortcut( Qt::SHIFT | Qt::Key_E );
-	selectAction->setShortcut( Qt::SHIFT | Qt::Key_S );
-	pitchBendAction->setShortcut( Qt::SHIFT | Qt::Key_T );
+	drawAction->setShortcut(combine(Qt::SHIFT, Qt::Key_D));
+	eraseAction->setShortcut(combine(Qt::SHIFT, Qt::Key_E));
+	selectAction->setShortcut(combine(Qt::SHIFT, Qt::Key_S));
+	pitchBendAction->setShortcut(combine(Qt::SHIFT, Qt::Key_T));

 	connect( editModeGroup, SIGNAL(triggered(int)), m_editor, SLOT(setEditMode(int)));

@@ -4826,9 +4826,9 @@ PianoRollWindow::PianoRollWindow() :

 	auto pasteAction = new QAction(embed::getIconPixmap("edit_paste"), tr("Paste (%1+V)").arg(UI_CTRL_KEY), this);

-	cutAction->setShortcut( Qt::CTRL | Qt::Key_X );
-	copyAction->setShortcut( Qt::CTRL | Qt::Key_C );
-	pasteAction->setShortcut( Qt::CTRL | Qt::Key_V );
+	cutAction->setShortcut(combine(Qt::CTRL, Qt::Key_X));
+	copyAction->setShortcut(combine(Qt::CTRL, Qt::Key_C));
+	pasteAction->setShortcut(combine(Qt::CTRL, Qt::Key_V));

 	connect( cutAction, SIGNAL(triggered()), m_editor, SLOT(cutSelectedNotes()));
 	connect( copyAction, SIGNAL(triggered()), m_editor, SLOT(copySelectedNotes()));
@@ -4849,19 +4849,19 @@ PianoRollWindow::PianoRollWindow() :

 	auto glueAction = new QAction(embed::getIconPixmap("glue"), tr("Glue"), noteToolsButton);
 	connect(glueAction, SIGNAL(triggered()), m_editor, SLOT(glueNotes()));
-	glueAction->setShortcut( Qt::SHIFT | Qt::Key_G );
+	glueAction->setShortcut(combine(Qt::SHIFT, Qt::Key_G));

 	auto knifeAction = new QAction(embed::getIconPixmap("edit_knife"), tr("Knife"), noteToolsButton);
 	connect(knifeAction, &QAction::triggered, m_editor, &PianoRoll::setKnifeAction);
-	knifeAction->setShortcut( Qt::SHIFT | Qt::Key_K );
+	knifeAction->setShortcut(combine(Qt::SHIFT, Qt::Key_K));

 	auto fillAction = new QAction(embed::getIconPixmap("fill"), tr("Fill"), noteToolsButton);
 	connect(fillAction, &QAction::triggered, [this](){ m_editor->fitNoteLengths(true); });
-	fillAction->setShortcut(Qt::SHIFT | Qt::Key_F);
+	fillAction->setShortcut(combine(Qt::SHIFT, Qt::Key_F));

 	auto cutOverlapsAction = new QAction(embed::getIconPixmap("cut_overlaps"), tr("Cut overlaps"), noteToolsButton);
 	connect(cutOverlapsAction, &QAction::triggered, [this](){ m_editor->fitNoteLengths(false); });
-	cutOverlapsAction->setShortcut(Qt::SHIFT | Qt::Key_C);
+	cutOverlapsAction->setShortcut(combine(Qt::SHIFT, Qt::Key_C));

 	auto minLengthAction = new QAction(embed::getIconPixmap("min_length"), tr("Min length as last"), noteToolsButton);
 	connect(minLengthAction, &QAction::triggered, [this](){ m_editor->constrainNoteLengths(false); });
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -28,5 +28,5 @@ foreach(LMMS_TEST_SRC IN LISTS LMMS_TESTS)
 		${QT_QTTEST_LIBRARY}
 	)

-	target_compile_features(${LMMS_TEST_NAME} PRIVATE cxx_std_17)
+	target_compile_features(${LMMS_TEST_NAME} PRIVATE cxx_std_20)
 endforeach()