Qt QMainWindow - Valgrind 报告内存泄漏
Qt QMainWindow - Valgrind reports memory leaks
我在生产代码中收到来自 valgrind 的内存泄漏报告。因此，很自然地，我将其缩小为一个最小的可编译示例。奇怪的是，我不得不“最小化它”，以至于除了 Qt 的实例化 Window!
Qt 有问题吗？我没有正确调用 valgrind 吗？
我的工具和版本，来自 Centos 7：
cmake3 3.17.2
gcc 8.3.1
Qt 5.14
valgrind 3.14.0
它目前已在 https://github.com/ChristopherPisz/QMainWindowLeaks 登记到我的 github 中，但是，当它不再存在时，我会把它列在这里以备将来使用。
mainwindow.ui
<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
<class>MainWindow</class>
<widget class="QMainWindow" name="MainWindow">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>800</width>
<height>600</height>
</rect>
</property>
<property name="windowTitle">
<string>Qt MainWindow Leaks</string>
</property>
<widget class="QWidget" name="centralwidget">
<property name="sizePolicy">
<sizepolicy hsizetype="Expanding" vsizetype="Expanding">
<horstretch>1</horstretch>
<verstretch>1</verstretch>
</sizepolicy>
</property>
<layout class="QHBoxLayout" name="horizontalLayout"/>
</widget>
<widget class="QMenuBar" name="menubar">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>800</width>
<height>25</height>
</rect>
</property>
</widget>
<widget class="QStatusBar" name="statusbar"/>
<action name="actionExit">
<property name="text">
<string>Exit</string>
</property>
</action>
</widget>
<resources/>
<connections/>
</ui>
mainwindow.hpp
#ifndef QTPROBLEMS_MAINWINDOW_HPP
#define QTPROBLEMS_MAINWINDOW_HPP
#include <QMainWindow>
QT_BEGIN_NAMESPACE
namespace Ui
{
class MainWindow;
}
QT_END_NAMESPACE
class MainWindow final : public QMainWindow
{
Q_OBJECT
public:
explicit MainWindow(QWidget* parent = nullptr);
~MainWindow() override;
private:
Ui::MainWindow* m_ui; ///< Qt generated object that is the main window
};
#endif
mainwindow.cpp
#include "mainwindow.hpp"
#include "./ui_mainwindow.h"
MainWindow::MainWindow(QWidget* parent)
: QMainWindow(parent)
, m_ui(new Ui::MainWindow)
{
m_ui->setupUi(this);
}
MainWindow::~MainWindow()
{
delete m_ui;
}
main.cpp
#include "mainwindow.hpp"
#include <iostream>
#include <QtWidgets/QApplication>
int main(int argc, char** argv)
{
QApplication app(argc, argv);
MainWindow window;
window.show();
int returnCode = 1;
try
{
returnCode = QApplication::exec();
}
catch(std::exception& e)
{
std::cerr << "An unhandled std::exception has escaped the main event loop: {}", e.what();
}
catch(...)
{
std::cerr << "An unhandled exception, of unknown type, has escaped the main event loop";
}
return returnCode;
}
CmakeLists.txt
cmake_minimum_required(VERSION 3.0)
project(qtproblems)
set(CMAKE_CXX_STANDARD 17)
set(CMAKE_INCLUDE_CURRENT_DIR ON)
set(CMAKE_AUTOMOC ON)
set(CMAKE_AUTOUIC ON)
set(CMAKE_AUTORCC ON)
find_package(Qt5 5.14 REQUIRED COMPONENTS Core Widgets)
set(MOC_HEADERS
mainwindow.hpp
)
set(UI_FORMS
mainwindow.ui
)
add_executable(qtproblems
${MOC_HEADERS}
${UI_FORMS}
mainwindow.cpp
main.cpp
)
target_link_libraries(qtproblems PRIVATE
Qt5::Core
Qt5::Widgets
)
输出：
==26444== Memcheck, a memory error detector
==26444== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==26444== Using Valgrind-3.14.0 and LibVEX; rerun with -h for copyright info
==26444== Command: /home/cpisz/git-workspace/QMainWindowLeaks/cmake-build-debug/qtproblems
==26444== Parent PID: 31394
==26444==
==26444==
==26444== HEAP SUMMARY:
==26444== in use at exit: 305,230 bytes in 6,852 blocks
==26444== total heap usage: 107,812 allocs, 100,960 frees, 232,668,695 bytes allocated
==26444==
==26444== 38 bytes in 1 blocks are definitely lost in loss record 73 of 284
==26444== at 0x4C29E63: malloc (vg_replace_malloc.c:309)
==26444== by 0x1664CF1E: ???
==26444== by 0x1662FC54: ???
==26444== by 0x1327FC80: q_dbus_bus_get_private(DBusBusType, DBusError*) (qdbus_symbols_p.h:198)
==26444== by 0x13280818: QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData*) (qdbusconnection.cpp:263)
==26444== by 0x13286D27: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void, void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:152)
==26444== by 0x13286ABC: void QtPrivate::FunctionPointer<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call<QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:185)
==26444== by 0x13285FF3: QtPrivate::QSlotObject<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (qobjectdefs_impl.h:414)
==26444== by 0x670D63C: QtPrivate::QSlotObjectBase::call(QObject*, void**) (qobjectdefs_impl.h:394)
==26444== by 0x673DB2E: QMetaCallEvent::placeMetaCall(QObject*) (qobject.cpp:619)
==26444== by 0x673EAF3: QObject::event(QEvent*) (qobject.cpp:1339)
==26444== by 0x649CA55: QThread::event(QEvent*) (qthread.cpp:980)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:malloc
obj:*
obj:*
fun:_ZL22q_dbus_bus_get_private11DBusBusTypeP9DBusError
fun:_ZN22QDBusConnectionManager24executeConnectionRequestEPNS_21ConnectionRequestDataE
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJPN22QDBusConnectionManager21ConnectionRequestDataEEEEvMS4_FvS6_EE4callES9_PS4_PPv
fun:_ZN9QtPrivate15FunctionPointerIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEEE4callINS_4ListIJS3_EEEvEEvS5_PS1_PPv
fun:_ZN9QtPrivate11QSlotObjectIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEENS_4ListIJS3_EEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb
fun:_ZN9QtPrivate15QSlotObjectBase4callEP7QObjectPPv
fun:_ZN14QMetaCallEvent13placeMetaCallEP7QObject
fun:_ZN7QObject5eventEP6QEvent
fun:_ZN7QThread5eventEP6QEvent
}
==26444== 72 (24 direct, 48 indirect) bytes in 1 blocks are definitely lost in loss record 141 of 284
==26444== at 0x4C29E63: malloc (vg_replace_malloc.c:309)
==26444== by 0x1664ED05: ???
==26444== by 0x1664ED66: ???
==26444== by 0x1662F97D: ???
==26444== by 0x1327FC80: q_dbus_bus_get_private(DBusBusType, DBusError*) (qdbus_symbols_p.h:198)
==26444== by 0x13280818: QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData*) (qdbusconnection.cpp:263)
==26444== by 0x13286D27: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void, void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:152)
==26444== by 0x13286ABC: void QtPrivate::FunctionPointer<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call<QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:185)
==26444== by 0x13285FF3: QtPrivate::QSlotObject<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (qobjectdefs_impl.h:414)
==26444== by 0x670D63C: QtPrivate::QSlotObjectBase::call(QObject*, void**) (qobjectdefs_impl.h:394)
==26444== by 0x673DB2E: QMetaCallEvent::placeMetaCall(QObject*) (qobject.cpp:619)
==26444== by 0x673EAF3: QObject::event(QEvent*) (qobject.cpp:1339)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:malloc
obj:*
obj:*
obj:*
fun:_ZL22q_dbus_bus_get_private11DBusBusTypeP9DBusError
fun:_ZN22QDBusConnectionManager24executeConnectionRequestEPNS_21ConnectionRequestDataE
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJPN22QDBusConnectionManager21ConnectionRequestDataEEEEvMS4_FvS6_EE4callES9_PS4_PPv
fun:_ZN9QtPrivate15FunctionPointerIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEEE4callINS_4ListIJS3_EEEvEEvS5_PS1_PPv
fun:_ZN9QtPrivate11QSlotObjectIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEENS_4ListIJS3_EEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb
fun:_ZN9QtPrivate15QSlotObjectBase4callEP7QObjectPPv
fun:_ZN14QMetaCallEvent13placeMetaCallEP7QObject
fun:_ZN7QObject5eventEP6QEvent
}
==26444== 73 bytes in 1 blocks are definitely lost in loss record 142 of 284
==26444== at 0x4C29E63: malloc (vg_replace_malloc.c:309)
==26444== by 0x1664CF1E: ???
==26444== by 0x1662F3B4: ???
==26444== by 0x1662FAC2: ???
==26444== by 0x1327FC80: q_dbus_bus_get_private(DBusBusType, DBusError*) (qdbus_symbols_p.h:198)
==26444== by 0x13280818: QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData*) (qdbusconnection.cpp:263)
==26444== by 0x13286D27: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void, void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:152)
==26444== by 0x13286ABC: void QtPrivate::FunctionPointer<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call<QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:185)
==26444== by 0x13285FF3: QtPrivate::QSlotObject<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (qobjectdefs_impl.h:414)
==26444== by 0x670D63C: QtPrivate::QSlotObjectBase::call(QObject*, void**) (qobjectdefs_impl.h:394)
==26444== by 0x673DB2E: QMetaCallEvent::placeMetaCall(QObject*) (qobject.cpp:619)
==26444== by 0x673EAF3: QObject::event(QEvent*) (qobject.cpp:1339)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:malloc
obj:*
obj:*
obj:*
fun:_ZL22q_dbus_bus_get_private11DBusBusTypeP9DBusError
fun:_ZN22QDBusConnectionManager24executeConnectionRequestEPNS_21ConnectionRequestDataE
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJPN22QDBusConnectionManager21ConnectionRequestDataEEEEvMS4_FvS6_EE4callES9_PS4_PPv
fun:_ZN9QtPrivate15FunctionPointerIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEEE4callINS_4ListIJS3_EEEvEEvS5_PS1_PPv
fun:_ZN9QtPrivate11QSlotObjectIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEENS_4ListIJS3_EEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb
fun:_ZN9QtPrivate15QSlotObjectBase4callEP7QObjectPPv
fun:_ZN14QMetaCallEvent13placeMetaCallEP7QObject
fun:_ZN7QObject5eventEP6QEvent
}
==26444== 73 bytes in 1 blocks are definitely lost in loss record 143 of 284
==26444== at 0x4C29E63: malloc (vg_replace_malloc.c:309)
==26444== by 0x1664CF1E: ???
==26444== by 0x1662FCAD: ???
==26444== by 0x1327FC80: q_dbus_bus_get_private(DBusBusType, DBusError*) (qdbus_symbols_p.h:198)
==26444== by 0x13280818: QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData*) (qdbusconnection.cpp:263)
==26444== by 0x13286D27: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void, void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:152)
==26444== by 0x13286ABC: void QtPrivate::FunctionPointer<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call<QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:185)
==26444== by 0x13285FF3: QtPrivate::QSlotObject<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (qobjectdefs_impl.h:414)
==26444== by 0x670D63C: QtPrivate::QSlotObjectBase::call(QObject*, void**) (qobjectdefs_impl.h:394)
==26444== by 0x673DB2E: QMetaCallEvent::placeMetaCall(QObject*) (qobject.cpp:619)
==26444== by 0x673EAF3: QObject::event(QEvent*) (qobject.cpp:1339)
==26444== by 0x649CA55: QThread::event(QEvent*) (qthread.cpp:980)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:malloc
obj:*
obj:*
fun:_ZL22q_dbus_bus_get_private11DBusBusTypeP9DBusError
fun:_ZN22QDBusConnectionManager24executeConnectionRequestEPNS_21ConnectionRequestDataE
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJPN22QDBusConnectionManager21ConnectionRequestDataEEEEvMS4_FvS6_EE4callES9_PS4_PPv
fun:_ZN9QtPrivate15FunctionPointerIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEEE4callINS_4ListIJS3_EEEvEEvS5_PS1_PPv
fun:_ZN9QtPrivate11QSlotObjectIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEENS_4ListIJS3_EEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb
fun:_ZN9QtPrivate15QSlotObjectBase4callEP7QObjectPPv
fun:_ZN14QMetaCallEvent13placeMetaCallEP7QObject
fun:_ZN7QObject5eventEP6QEvent
fun:_ZN7QThread5eventEP6QEvent
}
==26444== 520 bytes in 13 blocks are definitely lost in loss record 198 of 284
==26444== at 0x4C29E63: malloc (vg_replace_malloc.c:309)
==26444== by 0x16655141: ???
==26444== by 0x16648EF4: ???
==26444== by 0x16649068: ???
==26444== by 0x1664D509: ???
==26444== by 0x16641F8A: ???
==26444== by 0x1327FDED: q_dbus_get_local_machine_id() (qdbus_symbols_p.h:435)
==26444== by 0x13282716: QDBusConnection::localMachineId() (qdbusconnection.cpp:1251)
==26444== by 0x163F7054: QIBusPlatformInputContextPrivate::getSocketPath() (qibusplatforminputcontext.cpp:733)
==26444== by 0x163F72B0: QIBusPlatformInputContextPrivate::createConnection() (qibusplatforminputcontext.cpp:741)
==26444== by 0x163F675F: QIBusPlatformInputContextPrivate::initBus() (qibusplatforminputcontext.cpp:648)
==26444== by 0x163F669E: QIBusPlatformInputContextPrivate::QIBusPlatformInputContextPrivate() (qibusplatforminputcontext.cpp:638)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:malloc
obj:*
obj:*
obj:*
obj:*
obj:*
fun:_ZL27q_dbus_get_local_machine_idv
fun:_ZN15QDBusConnection14localMachineIdEv
fun:_ZN32QIBusPlatformInputContextPrivate13getSocketPathEv
fun:_ZN32QIBusPlatformInputContextPrivate16createConnectionEv
fun:_ZN32QIBusPlatformInputContextPrivate7initBusEv
fun:_ZN32QIBusPlatformInputContextPrivateC1Ev
}
==26444== 545 (184 direct, 361 indirect) bytes in 1 blocks are definitely lost in loss record 199 of 284
==26444== at 0x4C2BF79: calloc (vg_replace_malloc.c:762)
==26444== by 0x1663CA74: ???
==26444== by 0x166414AE: ???
==26444== by 0x16649CB7: ???
==26444== by 0x16649DD2: ???
==26444== by 0x1664A87E: ???
==26444== by 0x1664B0F0: ???
==26444== by 0x16649A77: ???
==26444== by 0x16632FCC: ???
==26444== by 0x1328AB07: q_dbus_watch_handle(DBusWatch*, unsigned int) (qdbus_symbols_p.h:275)
==26444== by 0x13290700: QDBusConnectionPrivate::socketRead(int) (qdbusintegrator.cpp:1213)
==26444== by 0x132A6513: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<int>, void, void (QDBusConnectionPrivate::*)(int)>::call(void (QDBusConnectionPrivate::*)(int), QDBusConnectionPrivate*, void**) (qobjectdefs_impl.h:152)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:calloc
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
fun:_ZL19q_dbus_watch_handleP9DBusWatchj
fun:_ZN22QDBusConnectionPrivate10socketReadEi
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJiEEEvM22QDBusConnectionPrivateFviEE4callES7_PS5_PPv
}
==26444== 727 (184 direct, 543 indirect) bytes in 1 blocks are definitely lost in loss record 208 of 284
==26444== at 0x4C2BF79: calloc (vg_replace_malloc.c:762)
==26444== by 0x1663CA74: ???
==26444== by 0x1663D871: ???
==26444== by 0x1662F774: ???
==26444== by 0x1327FC3B: q_dbus_bus_register(DBusConnection*, DBusError*) (qdbus_symbols_p.h:195)
==26444== by 0x132808BE: QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData*) (qdbusconnection.cpp:276)
==26444== by 0x13286D27: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void, void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:152)
==26444== by 0x13286ABC: void QtPrivate::FunctionPointer<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call<QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:185)
==26444== by 0x13285FF3: QtPrivate::QSlotObject<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (qobjectdefs_impl.h:414)
==26444== by 0x670D63C: QtPrivate::QSlotObjectBase::call(QObject*, void**) (qobjectdefs_impl.h:394)
==26444== by 0x673DB2E: QMetaCallEvent::placeMetaCall(QObject*) (qobject.cpp:619)
==26444== by 0x673EAF3: QObject::event(QEvent*) (qobject.cpp:1339)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:calloc
obj:*
obj:*
obj:*
fun:_ZL19q_dbus_bus_registerP14DBusConnectionP9DBusError
fun:_ZN22QDBusConnectionManager24executeConnectionRequestEPNS_21ConnectionRequestDataE
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJPN22QDBusConnectionManager21ConnectionRequestDataEEEEvMS4_FvS6_EE4callES9_PS4_PPv
fun:_ZN9QtPrivate15FunctionPointerIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEEE4callINS_4ListIJS3_EEEvEEvS5_PS1_PPv
fun:_ZN9QtPrivate11QSlotObjectIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEENS_4ListIJS3_EEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb
fun:_ZN9QtPrivate15QSlotObjectBase4callEP7QObjectPPv
fun:_ZN14QMetaCallEvent13placeMetaCallEP7QObject
fun:_ZN7QObject5eventEP6QEvent
}
==26444== 727 (184 direct, 543 indirect) bytes in 1 blocks are definitely lost in loss record 209 of 284
==26444== at 0x4C2BF79: calloc (vg_replace_malloc.c:762)
==26444== by 0x1663CA74: ???
==26444== by 0x166409BA: ???
==26444== by 0x16643857: ???
==26444== by 0x166336FD: ???
==26444== by 0x166339BF: ???
==26444== by 0x1662F793: ???
==26444== by 0x1327FC3B: q_dbus_bus_register(DBusConnection*, DBusError*) (qdbus_symbols_p.h:195)
==26444== by 0x132808BE: QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData*) (qdbusconnection.cpp:276)
==26444== by 0x13286D27: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void, void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:152)
==26444== by 0x13286ABC: void QtPrivate::FunctionPointer<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call<QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:185)
==26444== by 0x13285FF3: QtPrivate::QSlotObject<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (qobjectdefs_impl.h:414)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:calloc
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
fun:_ZL19q_dbus_bus_registerP14DBusConnectionP9DBusError
fun:_ZN22QDBusConnectionManager24executeConnectionRequestEPNS_21ConnectionRequestDataE
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJPN22QDBusConnectionManager21ConnectionRequestDataEEEEvMS4_FvS6_EE4callES9_PS4_PPv
fun:_ZN9QtPrivate15FunctionPointerIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEEE4callINS_4ListIJS3_EEEvEEvS5_PS1_PPv
fun:_ZN9QtPrivate11QSlotObjectIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEENS_4ListIJS3_EEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb
}
==26444== 1,119 (368 direct, 751 indirect) bytes in 2 blocks are definitely lost in loss record 232 of 284
==26444== at 0x4C2BF79: calloc (vg_replace_malloc.c:762)
==26444== by 0x1663CA74: ???
==26444== by 0x166414AE: ???
==26444== by 0x16649CB7: ???
==26444== by 0x16649DD2: ???
==26444== by 0x1664A87E: ???
==26444== by 0x1664AFD5: ???
==26444== by 0x16649B79: ???
==26444== by 0x166329FB: ???
==26444== by 0x166333DC: ???
==26444== by 0x166339D9: ???
==26444== by 0x1662F793: ???
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:calloc
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
}
==26444== LEAK SUMMARY:
==26444== definitely lost: 1,648 bytes in 22 blocks
==26444== indirectly lost: 2,246 bytes in 12 blocks
==26444== possibly lost: 0 bytes in 0 blocks
==26444== still reachable: 301,336 bytes in 6,818 blocks
==26444== suppressed: 0 bytes in 0 blocks
==26444== Reachable blocks (those to which a pointer was found) are not shown.
==26444== To see them, rerun with: --leak-check=full --show-leak-kinds=all
==26444==
==26444== For counts of detected and suppressed errors, rerun with: -v
==26444== ERROR SUMMARY: 9 errors from 9 contexts (suppressed: 0 from 0)
这对于某些类型的库来说是正常的，例如 C 标准库。这就是为什么你需要 Valgrind 抑制文件，所以它知道哪些泄漏是正常的。为了轻松获得 Qt 的良好抑制数据，运行 Qt Creator (documentation link) 下的 Valgrind。
原因是，库会为与操作系统（例如窗口系统）通信之类的事情保留内存，但无法控制何时 您的 应用程序不再需要它。它可以通过退出挂钩在应用程序退出时释放，但整个应用程序将从内存中删除，因此进行内存清理只会减慢应用程序关闭的速度，几乎没有任何好处。
请注意，随着 C++ 对象超出范围，大部分 内存仍会被清理。 C++ 对象无论如何都需要调用它们的析构函数，这通常由 delete 为堆中的对象完成。此外，这绝对不是您应该在普通 C++ 应用程序代码中优化的内容。在退出时分配的库（并且需要 Valgrind 抑制）通常是低级的东西，对整个应用程序是全局的，不属于单个 C++ 对象实例。
我在生产代码中收到来自 valgrind 的内存泄漏报告。因此，很自然地，我将其缩小为一个最小的可编译示例。奇怪的是，我不得不“最小化它”，以至于除了 Qt 的实例化 Window!
Qt 有问题吗？我没有正确调用 valgrind 吗？
我的工具和版本，来自 Centos 7：
cmake3 3.17.2
gcc 8.3.1
Qt 5.14
valgrind 3.14.0
它目前已在 https://github.com/ChristopherPisz/QMainWindowLeaks 登记到我的 github 中，但是，当它不再存在时，我会把它列在这里以备将来使用。
mainwindow.ui
<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
<class>MainWindow</class>
<widget class="QMainWindow" name="MainWindow">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>800</width>
<height>600</height>
</rect>
</property>
<property name="windowTitle">
<string>Qt MainWindow Leaks</string>
</property>
<widget class="QWidget" name="centralwidget">
<property name="sizePolicy">
<sizepolicy hsizetype="Expanding" vsizetype="Expanding">
<horstretch>1</horstretch>
<verstretch>1</verstretch>
</sizepolicy>
</property>
<layout class="QHBoxLayout" name="horizontalLayout"/>
</widget>
<widget class="QMenuBar" name="menubar">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>800</width>
<height>25</height>
</rect>
</property>
</widget>
<widget class="QStatusBar" name="statusbar"/>
<action name="actionExit">
<property name="text">
<string>Exit</string>
</property>
</action>
</widget>
<resources/>
<connections/>
</ui>
mainwindow.hpp
#ifndef QTPROBLEMS_MAINWINDOW_HPP
#define QTPROBLEMS_MAINWINDOW_HPP
#include <QMainWindow>
QT_BEGIN_NAMESPACE
namespace Ui
{
class MainWindow;
}
QT_END_NAMESPACE
class MainWindow final : public QMainWindow
{
Q_OBJECT
public:
explicit MainWindow(QWidget* parent = nullptr);
~MainWindow() override;
private:
Ui::MainWindow* m_ui; ///< Qt generated object that is the main window
};
#endif
mainwindow.cpp
#include "mainwindow.hpp"
#include "./ui_mainwindow.h"
MainWindow::MainWindow(QWidget* parent)
: QMainWindow(parent)
, m_ui(new Ui::MainWindow)
{
m_ui->setupUi(this);
}
MainWindow::~MainWindow()
{
delete m_ui;
}
main.cpp
#include "mainwindow.hpp"
#include <iostream>
#include <QtWidgets/QApplication>
int main(int argc, char** argv)
{
QApplication app(argc, argv);
MainWindow window;
window.show();
int returnCode = 1;
try
{
returnCode = QApplication::exec();
}
catch(std::exception& e)
{
std::cerr << "An unhandled std::exception has escaped the main event loop: {}", e.what();
}
catch(...)
{
std::cerr << "An unhandled exception, of unknown type, has escaped the main event loop";
}
return returnCode;
}
CmakeLists.txt
cmake_minimum_required(VERSION 3.0)
project(qtproblems)
set(CMAKE_CXX_STANDARD 17)
set(CMAKE_INCLUDE_CURRENT_DIR ON)
set(CMAKE_AUTOMOC ON)
set(CMAKE_AUTOUIC ON)
set(CMAKE_AUTORCC ON)
find_package(Qt5 5.14 REQUIRED COMPONENTS Core Widgets)
set(MOC_HEADERS
mainwindow.hpp
)
set(UI_FORMS
mainwindow.ui
)
add_executable(qtproblems
${MOC_HEADERS}
${UI_FORMS}
mainwindow.cpp
main.cpp
)
target_link_libraries(qtproblems PRIVATE
Qt5::Core
Qt5::Widgets
)
输出：
==26444== Memcheck, a memory error detector
==26444== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==26444== Using Valgrind-3.14.0 and LibVEX; rerun with -h for copyright info
==26444== Command: /home/cpisz/git-workspace/QMainWindowLeaks/cmake-build-debug/qtproblems
==26444== Parent PID: 31394
==26444==
==26444==
==26444== HEAP SUMMARY:
==26444== in use at exit: 305,230 bytes in 6,852 blocks
==26444== total heap usage: 107,812 allocs, 100,960 frees, 232,668,695 bytes allocated
==26444==
==26444== 38 bytes in 1 blocks are definitely lost in loss record 73 of 284
==26444== at 0x4C29E63: malloc (vg_replace_malloc.c:309)
==26444== by 0x1664CF1E: ???
==26444== by 0x1662FC54: ???
==26444== by 0x1327FC80: q_dbus_bus_get_private(DBusBusType, DBusError*) (qdbus_symbols_p.h:198)
==26444== by 0x13280818: QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData*) (qdbusconnection.cpp:263)
==26444== by 0x13286D27: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void, void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:152)
==26444== by 0x13286ABC: void QtPrivate::FunctionPointer<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call<QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:185)
==26444== by 0x13285FF3: QtPrivate::QSlotObject<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (qobjectdefs_impl.h:414)
==26444== by 0x670D63C: QtPrivate::QSlotObjectBase::call(QObject*, void**) (qobjectdefs_impl.h:394)
==26444== by 0x673DB2E: QMetaCallEvent::placeMetaCall(QObject*) (qobject.cpp:619)
==26444== by 0x673EAF3: QObject::event(QEvent*) (qobject.cpp:1339)
==26444== by 0x649CA55: QThread::event(QEvent*) (qthread.cpp:980)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:malloc
obj:*
obj:*
fun:_ZL22q_dbus_bus_get_private11DBusBusTypeP9DBusError
fun:_ZN22QDBusConnectionManager24executeConnectionRequestEPNS_21ConnectionRequestDataE
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJPN22QDBusConnectionManager21ConnectionRequestDataEEEEvMS4_FvS6_EE4callES9_PS4_PPv
fun:_ZN9QtPrivate15FunctionPointerIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEEE4callINS_4ListIJS3_EEEvEEvS5_PS1_PPv
fun:_ZN9QtPrivate11QSlotObjectIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEENS_4ListIJS3_EEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb
fun:_ZN9QtPrivate15QSlotObjectBase4callEP7QObjectPPv
fun:_ZN14QMetaCallEvent13placeMetaCallEP7QObject
fun:_ZN7QObject5eventEP6QEvent
fun:_ZN7QThread5eventEP6QEvent
}
==26444== 72 (24 direct, 48 indirect) bytes in 1 blocks are definitely lost in loss record 141 of 284
==26444== at 0x4C29E63: malloc (vg_replace_malloc.c:309)
==26444== by 0x1664ED05: ???
==26444== by 0x1664ED66: ???
==26444== by 0x1662F97D: ???
==26444== by 0x1327FC80: q_dbus_bus_get_private(DBusBusType, DBusError*) (qdbus_symbols_p.h:198)
==26444== by 0x13280818: QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData*) (qdbusconnection.cpp:263)
==26444== by 0x13286D27: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void, void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:152)
==26444== by 0x13286ABC: void QtPrivate::FunctionPointer<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call<QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:185)
==26444== by 0x13285FF3: QtPrivate::QSlotObject<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (qobjectdefs_impl.h:414)
==26444== by 0x670D63C: QtPrivate::QSlotObjectBase::call(QObject*, void**) (qobjectdefs_impl.h:394)
==26444== by 0x673DB2E: QMetaCallEvent::placeMetaCall(QObject*) (qobject.cpp:619)
==26444== by 0x673EAF3: QObject::event(QEvent*) (qobject.cpp:1339)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:malloc
obj:*
obj:*
obj:*
fun:_ZL22q_dbus_bus_get_private11DBusBusTypeP9DBusError
fun:_ZN22QDBusConnectionManager24executeConnectionRequestEPNS_21ConnectionRequestDataE
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJPN22QDBusConnectionManager21ConnectionRequestDataEEEEvMS4_FvS6_EE4callES9_PS4_PPv
fun:_ZN9QtPrivate15FunctionPointerIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEEE4callINS_4ListIJS3_EEEvEEvS5_PS1_PPv
fun:_ZN9QtPrivate11QSlotObjectIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEENS_4ListIJS3_EEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb
fun:_ZN9QtPrivate15QSlotObjectBase4callEP7QObjectPPv
fun:_ZN14QMetaCallEvent13placeMetaCallEP7QObject
fun:_ZN7QObject5eventEP6QEvent
}
==26444== 73 bytes in 1 blocks are definitely lost in loss record 142 of 284
==26444== at 0x4C29E63: malloc (vg_replace_malloc.c:309)
==26444== by 0x1664CF1E: ???
==26444== by 0x1662F3B4: ???
==26444== by 0x1662FAC2: ???
==26444== by 0x1327FC80: q_dbus_bus_get_private(DBusBusType, DBusError*) (qdbus_symbols_p.h:198)
==26444== by 0x13280818: QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData*) (qdbusconnection.cpp:263)
==26444== by 0x13286D27: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void, void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:152)
==26444== by 0x13286ABC: void QtPrivate::FunctionPointer<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call<QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:185)
==26444== by 0x13285FF3: QtPrivate::QSlotObject<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (qobjectdefs_impl.h:414)
==26444== by 0x670D63C: QtPrivate::QSlotObjectBase::call(QObject*, void**) (qobjectdefs_impl.h:394)
==26444== by 0x673DB2E: QMetaCallEvent::placeMetaCall(QObject*) (qobject.cpp:619)
==26444== by 0x673EAF3: QObject::event(QEvent*) (qobject.cpp:1339)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:malloc
obj:*
obj:*
obj:*
fun:_ZL22q_dbus_bus_get_private11DBusBusTypeP9DBusError
fun:_ZN22QDBusConnectionManager24executeConnectionRequestEPNS_21ConnectionRequestDataE
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJPN22QDBusConnectionManager21ConnectionRequestDataEEEEvMS4_FvS6_EE4callES9_PS4_PPv
fun:_ZN9QtPrivate15FunctionPointerIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEEE4callINS_4ListIJS3_EEEvEEvS5_PS1_PPv
fun:_ZN9QtPrivate11QSlotObjectIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEENS_4ListIJS3_EEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb
fun:_ZN9QtPrivate15QSlotObjectBase4callEP7QObjectPPv
fun:_ZN14QMetaCallEvent13placeMetaCallEP7QObject
fun:_ZN7QObject5eventEP6QEvent
}
==26444== 73 bytes in 1 blocks are definitely lost in loss record 143 of 284
==26444== at 0x4C29E63: malloc (vg_replace_malloc.c:309)
==26444== by 0x1664CF1E: ???
==26444== by 0x1662FCAD: ???
==26444== by 0x1327FC80: q_dbus_bus_get_private(DBusBusType, DBusError*) (qdbus_symbols_p.h:198)
==26444== by 0x13280818: QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData*) (qdbusconnection.cpp:263)
==26444== by 0x13286D27: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void, void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:152)
==26444== by 0x13286ABC: void QtPrivate::FunctionPointer<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call<QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:185)
==26444== by 0x13285FF3: QtPrivate::QSlotObject<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (qobjectdefs_impl.h:414)
==26444== by 0x670D63C: QtPrivate::QSlotObjectBase::call(QObject*, void**) (qobjectdefs_impl.h:394)
==26444== by 0x673DB2E: QMetaCallEvent::placeMetaCall(QObject*) (qobject.cpp:619)
==26444== by 0x673EAF3: QObject::event(QEvent*) (qobject.cpp:1339)
==26444== by 0x649CA55: QThread::event(QEvent*) (qthread.cpp:980)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:malloc
obj:*
obj:*
fun:_ZL22q_dbus_bus_get_private11DBusBusTypeP9DBusError
fun:_ZN22QDBusConnectionManager24executeConnectionRequestEPNS_21ConnectionRequestDataE
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJPN22QDBusConnectionManager21ConnectionRequestDataEEEEvMS4_FvS6_EE4callES9_PS4_PPv
fun:_ZN9QtPrivate15FunctionPointerIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEEE4callINS_4ListIJS3_EEEvEEvS5_PS1_PPv
fun:_ZN9QtPrivate11QSlotObjectIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEENS_4ListIJS3_EEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb
fun:_ZN9QtPrivate15QSlotObjectBase4callEP7QObjectPPv
fun:_ZN14QMetaCallEvent13placeMetaCallEP7QObject
fun:_ZN7QObject5eventEP6QEvent
fun:_ZN7QThread5eventEP6QEvent
}
==26444== 520 bytes in 13 blocks are definitely lost in loss record 198 of 284
==26444== at 0x4C29E63: malloc (vg_replace_malloc.c:309)
==26444== by 0x16655141: ???
==26444== by 0x16648EF4: ???
==26444== by 0x16649068: ???
==26444== by 0x1664D509: ???
==26444== by 0x16641F8A: ???
==26444== by 0x1327FDED: q_dbus_get_local_machine_id() (qdbus_symbols_p.h:435)
==26444== by 0x13282716: QDBusConnection::localMachineId() (qdbusconnection.cpp:1251)
==26444== by 0x163F7054: QIBusPlatformInputContextPrivate::getSocketPath() (qibusplatforminputcontext.cpp:733)
==26444== by 0x163F72B0: QIBusPlatformInputContextPrivate::createConnection() (qibusplatforminputcontext.cpp:741)
==26444== by 0x163F675F: QIBusPlatformInputContextPrivate::initBus() (qibusplatforminputcontext.cpp:648)
==26444== by 0x163F669E: QIBusPlatformInputContextPrivate::QIBusPlatformInputContextPrivate() (qibusplatforminputcontext.cpp:638)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:malloc
obj:*
obj:*
obj:*
obj:*
obj:*
fun:_ZL27q_dbus_get_local_machine_idv
fun:_ZN15QDBusConnection14localMachineIdEv
fun:_ZN32QIBusPlatformInputContextPrivate13getSocketPathEv
fun:_ZN32QIBusPlatformInputContextPrivate16createConnectionEv
fun:_ZN32QIBusPlatformInputContextPrivate7initBusEv
fun:_ZN32QIBusPlatformInputContextPrivateC1Ev
}
==26444== 545 (184 direct, 361 indirect) bytes in 1 blocks are definitely lost in loss record 199 of 284
==26444== at 0x4C2BF79: calloc (vg_replace_malloc.c:762)
==26444== by 0x1663CA74: ???
==26444== by 0x166414AE: ???
==26444== by 0x16649CB7: ???
==26444== by 0x16649DD2: ???
==26444== by 0x1664A87E: ???
==26444== by 0x1664B0F0: ???
==26444== by 0x16649A77: ???
==26444== by 0x16632FCC: ???
==26444== by 0x1328AB07: q_dbus_watch_handle(DBusWatch*, unsigned int) (qdbus_symbols_p.h:275)
==26444== by 0x13290700: QDBusConnectionPrivate::socketRead(int) (qdbusintegrator.cpp:1213)
==26444== by 0x132A6513: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<int>, void, void (QDBusConnectionPrivate::*)(int)>::call(void (QDBusConnectionPrivate::*)(int), QDBusConnectionPrivate*, void**) (qobjectdefs_impl.h:152)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:calloc
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
fun:_ZL19q_dbus_watch_handleP9DBusWatchj
fun:_ZN22QDBusConnectionPrivate10socketReadEi
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJiEEEvM22QDBusConnectionPrivateFviEE4callES7_PS5_PPv
}
==26444== 727 (184 direct, 543 indirect) bytes in 1 blocks are definitely lost in loss record 208 of 284
==26444== at 0x4C2BF79: calloc (vg_replace_malloc.c:762)
==26444== by 0x1663CA74: ???
==26444== by 0x1663D871: ???
==26444== by 0x1662F774: ???
==26444== by 0x1327FC3B: q_dbus_bus_register(DBusConnection*, DBusError*) (qdbus_symbols_p.h:195)
==26444== by 0x132808BE: QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData*) (qdbusconnection.cpp:276)
==26444== by 0x13286D27: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void, void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:152)
==26444== by 0x13286ABC: void QtPrivate::FunctionPointer<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call<QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:185)
==26444== by 0x13285FF3: QtPrivate::QSlotObject<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (qobjectdefs_impl.h:414)
==26444== by 0x670D63C: QtPrivate::QSlotObjectBase::call(QObject*, void**) (qobjectdefs_impl.h:394)
==26444== by 0x673DB2E: QMetaCallEvent::placeMetaCall(QObject*) (qobject.cpp:619)
==26444== by 0x673EAF3: QObject::event(QEvent*) (qobject.cpp:1339)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:calloc
obj:*
obj:*
obj:*
fun:_ZL19q_dbus_bus_registerP14DBusConnectionP9DBusError
fun:_ZN22QDBusConnectionManager24executeConnectionRequestEPNS_21ConnectionRequestDataE
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJPN22QDBusConnectionManager21ConnectionRequestDataEEEEvMS4_FvS6_EE4callES9_PS4_PPv
fun:_ZN9QtPrivate15FunctionPointerIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEEE4callINS_4ListIJS3_EEEvEEvS5_PS1_PPv
fun:_ZN9QtPrivate11QSlotObjectIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEENS_4ListIJS3_EEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb
fun:_ZN9QtPrivate15QSlotObjectBase4callEP7QObjectPPv
fun:_ZN14QMetaCallEvent13placeMetaCallEP7QObject
fun:_ZN7QObject5eventEP6QEvent
}
==26444== 727 (184 direct, 543 indirect) bytes in 1 blocks are definitely lost in loss record 209 of 284
==26444== at 0x4C2BF79: calloc (vg_replace_malloc.c:762)
==26444== by 0x1663CA74: ???
==26444== by 0x166409BA: ???
==26444== by 0x16643857: ???
==26444== by 0x166336FD: ???
==26444== by 0x166339BF: ???
==26444== by 0x1662F793: ???
==26444== by 0x1327FC3B: q_dbus_bus_register(DBusConnection*, DBusError*) (qdbus_symbols_p.h:195)
==26444== by 0x132808BE: QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData*) (qdbusconnection.cpp:276)
==26444== by 0x13286D27: QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void, void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:152)
==26444== by 0x13286ABC: void QtPrivate::FunctionPointer<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*)>::call<QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>(void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QDBusConnectionManager*, void**) (qobjectdefs_impl.h:185)
==26444== by 0x13285FF3: QtPrivate::QSlotObject<void (QDBusConnectionManager::*)(QDBusConnectionManager::ConnectionRequestData*), QtPrivate::List<QDBusConnectionManager::ConnectionRequestData*>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (qobjectdefs_impl.h:414)
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:calloc
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
fun:_ZL19q_dbus_bus_registerP14DBusConnectionP9DBusError
fun:_ZN22QDBusConnectionManager24executeConnectionRequestEPNS_21ConnectionRequestDataE
fun:_ZN9QtPrivate11FunctorCallINS_11IndexesListIJLi0EEEENS_4ListIJPN22QDBusConnectionManager21ConnectionRequestDataEEEEvMS4_FvS6_EE4callES9_PS4_PPv
fun:_ZN9QtPrivate15FunctionPointerIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEEE4callINS_4ListIJS3_EEEvEEvS5_PS1_PPv
fun:_ZN9QtPrivate11QSlotObjectIM22QDBusConnectionManagerFvPNS1_21ConnectionRequestDataEENS_4ListIJS3_EEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb
}
==26444== 1,119 (368 direct, 751 indirect) bytes in 2 blocks are definitely lost in loss record 232 of 284
==26444== at 0x4C2BF79: calloc (vg_replace_malloc.c:762)
==26444== by 0x1663CA74: ???
==26444== by 0x166414AE: ???
==26444== by 0x16649CB7: ???
==26444== by 0x16649DD2: ???
==26444== by 0x1664A87E: ???
==26444== by 0x1664AFD5: ???
==26444== by 0x16649B79: ???
==26444== by 0x166329FB: ???
==26444== by 0x166333DC: ???
==26444== by 0x166339D9: ???
==26444== by 0x1662F793: ???
==26444==
{
<insert_a_suppression_name_here>
Memcheck:Leak
match-leak-kinds: definite
fun:calloc
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
obj:*
}
==26444== LEAK SUMMARY:
==26444== definitely lost: 1,648 bytes in 22 blocks
==26444== indirectly lost: 2,246 bytes in 12 blocks
==26444== possibly lost: 0 bytes in 0 blocks
==26444== still reachable: 301,336 bytes in 6,818 blocks
==26444== suppressed: 0 bytes in 0 blocks
==26444== Reachable blocks (those to which a pointer was found) are not shown.
==26444== To see them, rerun with: --leak-check=full --show-leak-kinds=all
==26444==
==26444== For counts of detected and suppressed errors, rerun with: -v
==26444== ERROR SUMMARY: 9 errors from 9 contexts (suppressed: 0 from 0)
这对于某些类型的库来说是正常的，例如 C 标准库。这就是为什么你需要 Valgrind 抑制文件，所以它知道哪些泄漏是正常的。为了轻松获得 Qt 的良好抑制数据，运行 Qt Creator (documentation link) 下的 Valgrind。
原因是，库会为与操作系统（例如窗口系统）通信之类的事情保留内存，但无法控制何时 您的 应用程序不再需要它。它可以通过退出挂钩在应用程序退出时释放，但整个应用程序将从内存中删除，因此进行内存清理只会减慢应用程序关闭的速度，几乎没有任何好处。
请注意，随着 C++ 对象超出范围，大部分 内存仍会被清理。 C++ 对象无论如何都需要调用它们的析构函数，这通常由 delete 为堆中的对象完成。此外，这绝对不是您应该在普通 C++ 应用程序代码中优化的内容。在退出时分配的库（并且需要 Valgrind 抑制）通常是低级的东西，对整个应用程序是全局的，不属于单个 C++ 对象实例。