메모리 누수 확인

kim@ubuntu:~/Desktop$ cat ValGrindTest.c
# include <stdio.h>
# include <stdlib.h>
# include <string.h>

typedef struct _test_t {
 int data;
}test_t;

int main(void)
{
 test_t *test = NULL;
 test = (test_t*)malloc(sizeof(test_t));
 test->data = 3;
 printf("test->data = %d\n", test->data);

 return 0;
}

 

 

kim@ubuntu:~/Desktop$ valgrind ./ValGrindTest --tool=memcheck --leck-check=summary
==3775== Memcheck, a memory error detector
==3775== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==3775== Using Valgrind-3.12.0 and LibVEX; rerun with -h for copyright info
==3775== Command: ./ValGrindTest --tool=memcheck --leck-check=summary
==3775==
test->data = 3
==3775==
==3775== HEAP SUMMARY:
==3775==     in use at exit: 4 bytes in 1 blocks
==3775==   total heap usage: 2 allocs, 1 frees, 1,028 bytes allocated
==3775==
==3775== LEAK SUMMARY:
==3775==    definitely lost: 4 bytes in 1 blocks [4byte 짜리 1개 블럭이 현재 메모리 누수]
==3775==    indirectly lost: 0 bytes in 0 blocks
==3775==      possibly lost: 0 bytes in 0 blocks
==3775==    still reachable: 0 bytes in 0 blocks
==3775==         suppressed: 0 bytes in 0 blocks
==3775== Rerun with --leak-check=full to see details of leaked memory
==3775==
==3775== For counts of detected and suppressed errors, rerun with: -v
==3775== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

 

 

 

[코드 수정 후]

kim@ubuntu:~/Desktop$ valgrind ./ValGrindTest --tool=memcheck --leck-check=summary
==3824== Memcheck, a memory error detector
==3824== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==3824== Using Valgrind-3.12.0 and LibVEX; rerun with -h for copyright info
==3824== Command: ./ValGrindTest --tool=memcheck --leck-check=summary
==3824==
test->data = 3
==3824==
==3824== HEAP SUMMARY:
==3824==     in use at exit: 0 bytes in 0 blocks
==3824==   total heap usage: 2 allocs, 2 frees, 1,028 bytes allocated
==3824==
==3824== All heap blocks were freed -- no leaks are possible
==3824==
==3824== For counts of detected and suppressed errors, rerun with: -v
==3824== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)