c / intermediate
Snippet
Avoiding Memory Leaks with realloc
When using realloc, always use a temporary pointer. If realloc fails, it returns NULL but the original memory remains allocated.
snippet.c
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#include <stdlib.h>#include <stdio.h>int main() {int *arr = malloc(2 * sizeof(int));if (!arr) return 1;int *temp = realloc(arr, 10 * sizeof(int));if (!temp) {free(arr);return 1;}arr = temp;free(arr);return 0;}
Breakdown
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int *temp = realloc(arr, ...);
Store result in temp to prevent losing the original address on failure.
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if (!temp) { free(arr); }
Explicitly free the original buffer if the expansion fails.