Problem with disassembler and SIGILL signal

[mrjj]

@Amaury
Well you can declare it anywhere. :)
You want to try crash on purpose`?

[Amaury]

Yes I'd like to look at all my pointers, see if there's somewhere that one is not declared or thing like that.

[mrjj]

@Amaury

• one is not declared
  I assume you mean instantiated or in non japanese
  new'ed
  as in
  ClassX * varX = new X()

[Amaury]

Yes that's alright .

Btw I got a question , there's some code that I didn't develop myself and I was wondering if there could be an error in some parameters here's the setup :

main.cpp

static const QString path = "localhost";
DataBase MemTampon::Db(path);

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    QTextCodec::setCodecForCStrings(QTextCodec::codecForName("UTF-8"));
    QTextCodec::setCodecForTr(QTextCodec::codecForName("UTF-8"));

    QTranslator *qtTranslator = new QTranslator;
        qtTranslator->load("qt_" + QLocale::system().name(), QLibraryInfo::location(QLibraryInfo::TranslationsPath));
        a.installTranslator(qtTranslator);

        MemTampon::Db.aff_Temperature();
        MemTampon::Db.aff_Humidite();
        MemTampon::Db.aff_Puissance();
        MemTampon::Db.aff_Nom_SD();

    MainWindow w;
    w.show();

    return a.exec();

}

memtampon.h (memtampon.cpp is empty)

class MemTampon
{
public:
    static DataBase Db;
    static Options Opt;

};

and Database.cpp

DataBase::DataBase(const QString &path)
{
        db = QSqlDatabase::addDatabase("QMYSQL");
        db.setHostName("localhost");
        db.setDatabaseName("SmartDevice_DB_V1");
        db.setUserName("root");
        db.setPassword("root");

        if (!db.open())
        {
           qDebug() << "Error: connection with database fail";
        }
        else
        {
           qDebug() << "Database: connection ok";
        }
}

I assume that with the path variable I am able to call the functions that are in my cpp but, it tells me that path is an unused parameter could it possibly give me an error ?

[mrjj]

Its impossible to say
But global variables are good candidate to be check. (always)

I dont think
static const QString path;
can give such error.

[Amaury]

Thank you I was a little disapointed by this function and wasn't able to say if that was correct or not

[mrjj]

@Amaury
Well you can always single step it and see if something happens.

[kshegunov]

@Amaury
Also you can cut the code that you suspect and see if the problem manifest itself. I wouldn't in principle initialize anything outside of main (like your database) if I can help it, that way I stumble on to less errors in my code, and thus makes for an easier time debugging. Still, my best guess is there some subtle architecture mismatch, so the compiler generates a mostly valid code. However I have no clue how to really test that at present.

[Amaury]

By using step I can't see any bugs so that's not here.

By the way I'm using the memory check Valgind through QT and when I do a memory check thats starting but I got this message after a few seconds :

Analyzing memory of /home/pi/Desktop/SmartDevice/SauvegardeRASPI/New/build-SmartDevice_QT_V11-Desktop-Debug/SmartDevice_QT_V11
    <frame>
      <ip>0x485F6F0</ip>
      <obj>/usr/lib/arm-linux-gnueabihf/libarmmem.so</obj>
    </frame>
  </stack>
Analyzing finished.
** Unknown error **

I followed the steps here :
http://doc.qt.io/qtcreator/creator-valgrind-overview.html
http://doc.qt.io/qtcreator/creator-analyzer.html

[Amaury]

@kshegunov
If I don't declare it there where could I do it ? As said before that's not a code that I did myself and I don't really understand the way that it works (how the "path" is used thorugh the different pages ...

[kshegunov]

@Amaury said in Problem with disassembler and SIGILL signal:

If I don't declare it there where could I do it

From the looks of it you can safely put the db initialization in main (after you've created the application object). As for the string, it's okay to leave it as a global.

[Amaury]

@kshegunov

I tried like that but that doesn't work got a qualified-id in declaration before '(' token error

static const QString path = "localhost";

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    DataBase MemTampon::Db(path);
.
.
.
}

Even with the string inside the main ...

[kshegunov]

It should be:

DataBase Db(path);

You're not initializing a static anymore.

[Amaury]

The problem is if I don't use a static I can't do the calls for my other functions in my Database class..

const QString path = "localhost";

int main(int argc, char *argv[])
{

    QApplication a(argc, argv);


    QTextCodec::setCodecForCStrings(QTextCodec::codecForName("UTF-8"));
    QTextCodec::setCodecForTr(QTextCodec::codecForName("UTF-8"));

    QTranslator *qtTranslator = new QTranslator;
        qtTranslator->load("qt_" + QLocale::system().name(), QLibraryInfo::location(QLibraryInfo::TranslationsPath));
        a.installTranslator(qtTranslator);

        DataBase Db(path);
        DataBase::Db.aff_Temperature();
        DataBase::Db.aff_Humidite();
        DataBase::Db.aff_Puissance();
        DataBase::Db.aff_Nom_SD();

    MainWindow w;
    w.show();


    return a.exec();
}

(By the way I've delete the MemTampon that I agree was useless ... )

EDIT : My bad I'm dumb I think ^^ for the main it's alright just had to cut out the "DataBase::"

But I'm doing reference to the "Db" inside another page but the call doesn't work...

 if (Db.isOpen())
    {

        Temp  = Db.aff_Temperature();
        Humid  = Db.aff_Humidite();
        Puiss  = Db.aff_Puissance();
        Nom = Db.aff_Nom_SD();
        Axe_X = Db.aff_AxeX();
        Axe_Y = Db.aff_AxeY();
        Axe_Z = Db.aff_AxeZ();

[kshegunov]

@Amaury said in Problem with disassembler and SIGILL signal:

if I don't use a static I can't do the calls for my other functions in my Database class..

Why not, you can always get the opened database (it's default named) by calling QSqlDatabase db = QSqlDatabase::database(). The QSqlDatabase class already keeps track of the opened connections for you.

[Amaury]

So what you mean is that for now my function Database Db(path) is just to specify if the connection is opened or not ?

[kshegunov]

@Amaury
Eh, yes I suppose you could say that, currently in the constructor of your object you open the database:

db = QSqlDatabase::addDatabase("QMYSQL");
db.setHostName("localhost");
// ...

so it serves as database initialization. You can do that in main() too, but that's another point. After the constructor's run, you can get the opened database the way I mentioned in my previous post. In principle it's not really needed to have a "database manager" with Qt, because the QSqlDatabase class already keeps track of the connections, as mentioned. You can look up the two functions QSqlDatabase::addDatabase and QSqlDatabase::database in the docs and I think it'll become clear from the examples there.

[Amaury]

Alright I'm going to check and change some things to see if that deletes the Sigill signal (hope so) I come back to give you feedback.

Thanks !

[Amaury]

Hi there ,

I'm back again for some feedback , I changed the way I use my Database, I'm still connecting the same way, But all my functions that were in my class get swith into the only page that need those instructions .
That Way I Just connect through my databse page and just make a Signal Slot use when I need it.

That said , my problem isn't solve for now I though maybe it was the Databse but seems not , maybe it's my refresh timer for my UI that creates crashes , anyway I'm still triying to find the problem..

If anyone could give me a clue for Valgrind to work , it's crashing a few seconds after starting the analysis and I just have the message that I post earlier.

That's a big post thank's for help and if I can't get in touch happy Christmas holidays.