C 在拼写检查器中使用大小为8的未初始化值

我编写了一个拼写检查器，它使用trie来存储和检查拼写错误的单词。它将文本文件字典加载到内存中，接受单词以检查拼写错误，并卸载内存。程序编译成功，但运行时会产生分段错误。基于valgrind，问题似乎是在我的插入函数中使用了未初始化的值

//If word not present, inserts word into trie
//If the word is a prefix of a node, marks the "leaf node" (end-of-word node)
void insert(struct node *root, const char *word)
{
int length = strlen(word);
int index = 0;

//start from root node
struct node *tempNode = root;

for(int i = 0; i < length; i++)
{
    //if the current letter in word is a letter
    if(word[i] != '\'')

        //convert the alphabet to it's respective index number
        index = CHAR_TO_INDEX(tolower(word[i]));

    else
        //assign index number 27 (for apostrophe)
        index = INPUT_SIZE;

    //create a new node if path doesn't exist (is NULL)
    if(!(tempNode->children[index]))
        tempNode->children[index] = getNode();

        //go to next node  
        tempNode = tempNode->children[index];
        }
    //mark last node as leaf
    tempNode->isWord = true;
}

和getNode（），创建初始化为NULL的新节点：

    //Returns new trie node initialised to NULL
    struct node *getNode(void)
    {
    //initialise new node
    struct node *newNode = NULL;

    newNode = malloc(sizeof(struct node));

    //proceed if enough memory to allocate
    if(newNode) 
    {
    //initialise pointers
    for(int i = 0; i < INPUT_SIZE; i++)
        newNode->children[i] = NULL;

    newNode->isWord = false;
    }
    else return false;

    return newNode;
    }

valgrind在--leak check=full、--leak check=full和--show leak kinds=all的情况下运行。我曾尝试引用以前文章中类似的错误，但上下文的差异使我很难确定应该做什么。第84行的内容是if（！（tempNode->children[index]）。（在我看来）这似乎是问题的根源

谢谢大家!

while((ch = fgetc(file)) != '\n')
{
    word[counter] = ch;
    counter++;
}
//whole word found, insert word and reset counter, increment word count
insert(root, word);

这是导致未定义行为的代码部分

您的字符串

word

不是以null结尾的，但是

insert

希望它是以null结尾的（因为它做的第一件事是调用

strlen

，它需要以null结尾的字符串）

简单的解决办法是

word[counter] = '\0';

---

在调用

insert

之前，假设所有内容都在边界内。

调试器可能会告诉您的更多什么是结构节点？子节点是指针数组吗？这里可能有帮助。我在中添加了结构节点的定义。谢谢你的提问@伊兰

    Conditional jump or move depends on uninitialised value(s)
==9334==    at 0x4011DD: insert (dictionary.c:84)
==9334==    by 0x4014D1: load (dictionary.c:188)
==9334==    by 0x40095D: main (speller.c:40)
==9334==  Uninitialised value was created by a heap allocation
==9334==    at 0x4C2AB80: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==9334==    by 0x4010CB: getNode (dictionary.c:40)
==9334==    by 0x4011E7: insert (dictionary.c:85)
==9334==    by 0x4014D1: load (dictionary.c:188)
==9334==    by 0x40095D: main (speller.c:40)
==9334== 
==9334== Use of uninitialised value of size 8
==9334==    at 0x4011D5: insert (dictionary.c:84)
==9334==    by 0x4014D1: load (dictionary.c:188)
==9334==    by 0x40095D: main (speller.c:40)
==9334==  Uninitialised value was created by a heap allocation
==9334==    at 0x4C2AB80: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==9334==    by 0x4010CB: getNode (dictionary.c:40)
==9334==    by 0x4011E7: insert (dictionary.c:85)
==9334==    by 0x4014D1: load (dictionary.c:188)
==9334==    by 0x40095D: main (speller.c:40)
==9334== 
==9334== Invalid read of size 8
==9334==    at 0x4011D5: insert (dictionary.c:84)
==9334==    by 0x4014D1: load (dictionary.c:188)
==9334==    by 0x40095D: main (speller.c:40)
==9334==  Address 0x91 is not stack'd, malloc'd or (recently) free'd
==9334== 
==9334== 
==9334== Process terminating with default action of signal 11 (SIGSEGV)
==9334==  Access not within mapped region at address 0x91
==9334==    at 0x4011D5: insert (dictionary.c:84)
==9334==    by 0x4014D1: load (dictionary.c:188)
==9334==    by 0x40095D: main (speller.c:40)

while((ch = fgetc(file)) != '\n')
{
    word[counter] = ch;
    counter++;
}
//whole word found, insert word and reset counter, increment word count
insert(root, word);

word[counter] = '\0';