c - 重定位被截断以适合 : R_X86_64_PC32 against undefined symbol `cfree'

Question

我正在尝试在 Cygwin 中为 Win64 编译 C4.5 算法。我的错误为

besttree.o:besttree.c:(.text+0x240): undefined reference to `cfree'
besttree.o:besttree.c:(.text+0x240): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `cfree'

当我查看besttree.c时，我发现cfree位于

FormTarget(Size)
/*  -----------  */
    ItemNo Size;
{
    ItemNo i, *ClassFreq;
    ClassNo c, Smallest, ClassesLeft=0;

    ClassFreq = (ItemNo *) calloc(MaxClass+1, sizeof(ItemNo));



    while ( ClassesLeft )
    {
    /*  Find least common class of which there are some items  */

    Smallest = -1;
    ForEach(c, 0, MaxClass)
    {
        if ( ClassFreq[c] &&
         ( Smallest < 0 || ClassFreq[c] < ClassFreq[Smallest] ) )
        {
        Smallest = c;
        }
    }

    /*  Allocate the no. of items of this class to use in the window  */

    TargetClassFreq[Smallest] = Min(ClassFreq[Smallest], Round(Size/ClassesLeft));

    ClassFreq[Smallest] = 0;

    Size -= TargetClassFreq[Smallest];
    ClassesLeft--;
    }

    cfree(ClassFreq);
}

这次编译可能出现什么问题？是因为Cygwin for Win64编译的原因吗？我也找不到 cfree api 的来源。谢谢

Answer 1

我的经验是C4.5无法在Cygwin中编译，因为Cygwin没有像Linux中那样携带完整的库。所以我在我的 Windows 机器上安装 Ubuntu 作为虚拟操作系统。然后就可以编译成功了。