条件跳转或移动取决于未初始化的值

yot*_*moo 3 c valgrind

我一直在努力解决这个问题一段时间,寻找每一个可能的解决方案.我是C的新手,所以我很难.我知道我有一些未初始化的变量,但我找不到它们.我正在尝试打印矩阵.这是构造函数:

BoardP createNewBoard(int width, int high)
{  

    BoardP board = (BoardP) malloc(sizeof(Board));

    if (board == NULL)
    {
        reportError(MEM_OUT);
        return NULL;
    }
    board->height = high;
    board->width = width;
    board->board = (char**) malloc(high * sizeof(char*));
    int i;
    for (i=0; i<high; i++)
    {
        board->board[i] = (char*) malloc(width * sizeof(char));
        if (board->board[i] == NULL)
        {
            freeTempBoard(board,i);
            return NULL;
        }
    }

    return board;
}
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构造函数返回BoardP,一个对Board的pinter,它是:

typedef struct Board
{
    int width;
    int height;
    char **board;
} Board;
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现在我没有尝试打印板 - >板.我循环遍历矩阵,对于每个单元格,我调用此函数:

static void printChar(ConstBoardP board, int X, int Y)
{
    if (X>=board->height || Y>=board->width)
    {
        printf(" ");
    }
    else
    {
        printf("%c ",board->board[X][Y]); //!!THIS IS LINE 299 IN Board.c!!
    }
}
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而fianlly这是我得到的错误:

==4931== Conditional jump or move depends on uninitialised value(s)
==4931==    at 0x4E973D9: _IO_file_overflow@@GLIBC_2.2.5 (fileops.c:880)
==4931==    by 0x4E6F01B: vfprintf (vfprintf.c:1614)
==4931==    by 0x4E75879: printf (printf.c:35)
==4931==    by 0x400D91: printChar (Board.c:299)
==4931==    by 0x400CED: printBoard (Board.c:284)
==4931==    by 0x400F1A: main (PlayBoard.c:19)
==4931== 
==4931== Conditional jump or move depends on uninitialised value(s)
==4931==    at 0x4E97401: _IO_file_overflow@@GLIBC_2.2.5 (fileops.c:887)
==4931==    by 0x4E6F01B: vfprintf (vfprintf.c:1614)
==4931==    by 0x4E75879: printf (printf.c:35)
==4931==    by 0x400D91: printChar (Board.c:299)
==4931==    by 0x400CED: printBoard (Board.c:284)
==4931==    by 0x400F1A: main (PlayBoard.c:19)
==4931== 
==4931== Conditional jump or move depends on uninitialised value(s)
==4931==    at 0x4E6F025: vfprintf (vfprintf.c:1614)
==4931==    by 0x4E75879: printf (printf.c:35)
==4931==    by 0x400D91: printChar (Board.c:299)
==4931==    by 0x400CED: printBoard (Board.c:284)
==4931==    by 0x400F1A: main (PlayBoard.c:19)
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现在有另一个文件调用createNewBoard,然后创建printBoard(newBoard,0,0).唯一可能未被初始化的是董事会 - >董事会,除此之外,我没有任何想法.我不知道如何调试它.我知道很多文字,但我找不到问题.任何想法将不胜感激

cni*_*tar 5

尝试:

for (i=0; i<high; i++)
{
    board->board[i] = (char*) malloc(width * sizeof(char));
    /* ... */
    memset(board[i], 0, width);
}
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  • 此外,您可以对数组使用 calloc 而不是 malloc。 (3认同)