本周技术概要20231016-20231022与生活点滴

一、linux下Qt treeView内存泄漏

当把原来Qt程序由ubuntu 32位的程序迁移到ubuntu 64位时，测试程序发现了内存泄漏问题，经过排查，最终定位在Qt的treeView的setCurrentIndex调用上。到目前还没有排查出来，有遇到同样问题的同志可以一起交流下。程序测试demo在64位环境下有明显内存泄漏，但是同样程序在32位上运行正常，接下来可能要继续更换Qt的版本进行测试了。

目前推测就是Qt自身Widget库的问题。

测试环境：Linux ubuntu 4.15.0-142-generic #146~16.04.1-Ubuntu

测试程序如下：

头文件：

代码语言：javascript复制

/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
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** This file is part of the examples of the Qt Toolkit.
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#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QModelIndex>
#include <QTreeView>

QT_BEGIN_NAMESPACE
class QTreeView; //forward declarations
class QStandardItemModel;
class QStandardItem;
class QTimer;

QT_END_NAMESPACE


class MainWindow : public QMainWindow
{
    Q_OBJECT

private slots:
    void slot_valueIncrease();
    void slot_modelIndex(QModelIndex index);

private:
    QTreeView *treeView;

    QTreeView TreeView;

    QStandardItemModel *standardModel;
    QList<QStandardItem *> prepareRow(const QString &first) const;

    QTimer *timer_;
    int count{0};

    QStandardItem *root_;
    QStandardItem *first_;
    QStandardItem *second_;


public:
    MainWindow(QWidget *parent = nullptr);
};

#endif // MAINWINDOW_H

‍

cpp文件：

代码语言：javascript复制

    root_ = new QStandardItem("root");
    first_ = new QStandardItem("first");
    second_ = new QStandardItem("second");

    first_->appendRow(second_);
    root_->appendRow(first_);
定时器溢出后：
    treeView->setCurrentIndex(first_->index());
    treeView->setCurrentIndex(second_->index());

最后使用top指令观察RES值，会有明显连续增加。程序运行效果：