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POC - realloc causes an issue with structure
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  1. POC - realloc causes an issue with structure
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    copied!<p>First of all, my appology that the code I post below is a bit ambiguous, since I have to simplify it in a way that readers can understand (the original code is quite complicated).</p> <p>In the code below:</p> <ol> <li>There is a list of 10 items.</li> <li>Each item has a list of info about it.</li> <li>Each info has a list of name.</li> </ol> <p>So I'm trying to populate the list of items, but I failed at reallocate the memory on line that I marked "<code>&lt;&lt;&lt;&lt;</code>". There is no compiling error, but when I print all the items's names out, it doesn't print any of those. I did some debugging on it and I'm pretty sure that the line "<code>&lt;&lt;&lt;&lt;</code>" causes an error, but I don't know why.</p> <pre><code>typedef struct { char *name; } NAME; typedef struct { int id; int nNames; NAME *names; } INFO; typedef struct { INFO *info; } ITEM; void *buildListInfo(LIST *list) { if (list != NULL) { list-&gt;nNames++; list-&gt;names = realloc(list-&gt;names, sizeof(INFO) * list-&gt;nNames++); // &lt;&lt;&lt;&lt; list-&gt;names[list-&gt;nNames-1].name = "example"; // index 0 first } return list; } int main() { int itemSize = 10; ITEM *items = malloc(sizeof(ITEM)*itemSize); for (int i = 0; i &lt; ind-&gt;nTerms; i++) { items[i].info = malloc(sizeof(INFO)); } /* construct an array that holds the number of lists that an item has */ int num[itemSize]; for (int i = 0; i &lt; itemSize; i++) { num[i] = 0; } /* build all items, each item has a list that contains its info (many) */ while (&lt;some_finite_condition&gt;) for (int i = 0; i &lt; itemSize; i++) { items[i].info[num[i]] = *buildList(&amp;(items[i].info[list[i]])); num[i]++; } } } </code></pre>
 

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