public int hp { get; set; }

これを

public int hp {
get {
return this.hp;
}
set {
this.hp = value;
}
}

って書き換えると下記のエラーがでる。なんでさ。。。

StackOverflowException: The requested operation caused a stack overflow.
PlayerInfo.set_hp (Int32 value) (at Assets/Scripts/Player/PlayerInfo.cs:13)
PlayerInfo.set_hp (Int32 value) (at Assets/Scripts/Player/PlayerInfo.cs:13)
PlayerInfo.set_hp (Int32 value) (at Assets/Scripts/Player/PlayerInfo.cs:13)
PlayerInfo.set_hp (Int32 value) (at Assets/Scripts/Player/PlayerInfo.cs:13)
PlayerInfo.set_hp (Int32 value) (at Assets/Scripts/Player/PlayerInfo.cs:13)
PlayerInfo.set_hp (Int32 value) (at Assets/Scripts/Player/PlayerInfo.cs:13)