Two functions making my game crash when running in a row - c++

Question

I usually find answers for my problems on this forum, but this time I can't. This is why I am asking you. (Sorry in advance for the mistakes I'm doing in english or c++)
So here is my void function, it is just the start of a little game I'm making in the console. It is just showing some informations. By the way it's a french game, but I don't think that a traduction is needed to solve my problem.
void showIntro (Personnage a, Personnage b, Personnage c)
{
cout << endl;
cout << "VOUS ENTREZ DANS LES MINES DE LA MORIA" << endl << endl;
cout << "ENNEMIS PRESENTS : " << endl << endl;
cout << " " << "Orc robuste" << endl << endl << endl;
a.afficherEtatIntro ();
cout << endl << endl;
cout << " " << "Orc robuste" << endl << endl << endl;
b.afficherEtatIntro ();
cout << endl << endl;
cout << " " << "Orc robuste" << endl << endl << endl;
c.afficherEtatIntro ();
cout << endl << endl;
cout << "Le combat va commencer";
Sleep(1000);
cout << ".";
Sleep(1000);
cout << ".";
Sleep(1000);
cout << "." << endl << endl << endl;
cout << "Gimli : ";
string phraseGimli ("Je vengerai mes freres!");
for (int f = 0; f <= phraseGimli.size(); f++) // Just writing a sentence
{
cout << phraseGimli[f];
Sleep(100);
}
cout << endl << "Legolas : ";
string phraseLegolas ("Nous sommes avec toi mon ami");
for (int g = 0; g <= phraseLegolas.size(); g++) // Writing a sentence
{
cout << phraseLegolas[g];
Sleep(100);
}
cout << endl << "Aragorn : ";
string phraseAragorn ("POUR LE GONDOR");
for (int i = 0; i <= phraseAragorn.size(); i++) // Writing a sentence
{
cout << phraseAragorn[i];
Sleep(100);
}
}
And here is the other one.
void choixAttaque (Personnage joueur, Personnage a, Personnage b, Personnage c, string nom)
{
cout << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl << endl;
cout << "Qui souhaitez vous attaquer ?" << endl;
cout << endl;
cout << endl;
cout << " " << nom << endl << endl << endl;
a.afficherEtatIntro ();
cout << endl << "Tapez 1" << endl;
cout << " " << nom << endl << endl << endl;
b.afficherEtatIntro ();
cout << endl << "Tapez 2" << endl;
cout << " " << nom << endl << endl << endl;
c.afficherEtatIntro ();
cout << endl << "Tapez 3" << endl;
int choix;
do
{
cin >> choix;
} while (choix <= 0 || choix >= 4);
switch (choix)
{
case 1:
joueur.attaquer(a);
case 2:
joueur.attaquer(b);
case 3:
joueur.attaquer(c);
}
}
afficherEtatIntro ()
void Personnage::afficherEtatIntro () const
{
cout << " " << "Vie : " << m_vie << endl;
cout << " ";
m_arme->afficher();
}
m_arme means m_weapon, I used "->" because it is from a pointer. I'm new to all of this, so it can be really possible that the mistake comes from here.
When I'm using only one, it works, but when I'm using both in a row, it does that.
first void function showing properly
And then.
Path of things in my computer
I hope I gave the informations needed to solve the problem, and I hope it can be solved. Thanks in advance for everything, and sorry for all the mistakes I may have made in english, c++ or by linking my lines of code. ^^'
(Btw, all the "cout << endl;" looks ugly I guess, but that is just until I learn how to use Qt..)
From debugger: "Program received signal SIGSEGV, Segmentation fault."
And a picture in comment. (Need more reputation for 3 links..)