From: http://bbs.chinaunix.net/thread-908769-1-1.html
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如题。 ------------------------------- 找到了! http://www.valgrind.org/ 同时附一个转自 http://blog.chinaunix.net/u/18381/showart.php?id=162015 的示例: #include <stdlib.h> void f(void) { int* x = malloc(10 * sizeof(int)); x[10] = 0; // problem 1: heap block overrun } // problem 2: memory leak -- x not freed int main(void) { f(); return 0; } 编译代码: gcc -Wall example.c -g -o example 注意：gcc 的-g 选项让Valgrind调试输出时指出相应信息的代码所在的行号。 运行valgrind: valgrind --tool=memcheck --leak-check=yes ./example valgrind的执行结果: ==6742== Memcheck, a memory error detector for x86-linux. ==6742== Copyright (C) 2002-2004, and GNU GPL'd, by Julian Seward et al. ==6742== Using valgrind-2.2.0, a program supervision framework for x86-linux. ==6742== Copyright (C) 2000-2004, and GNU GPL'd, by Julian Seward et al. ==6742== For more details, rerun with: -v ==6742== ==6742== Invalid write of size 4 ==6742== at 0x8048384: f (example.c:6) ==6742== by 0x80483AC: main (example.c:12) ==6742== Address 0x1B908050 is 0 bytes after a block of size 40 alloc'd ==6742== at 0x1B904984: malloc (vg_replace_malloc.c:131) ==6742== by 0x8048377: f (example.c:5) ==6742== by 0x80483AC: main (example.c:12) ==6742== ==6742== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 12 from 1) ==6742== malloc/free: in use at exit: 40 bytes in 1 blocks. ==6742== malloc/free: 1 allocs, 0 frees, 40 bytes allocated. ==6742== For counts of detected errors, rerun with: -v ==6742== searching for pointers to 1 not-freed blocks. ==6742== checked 1360800 bytes. ==6742== ==6742== ==6742== 40 bytes in 1 blocks are definitely lost in loss record 1 of 1 ==6742== at 0x1B904984: malloc (vg_replace_malloc.c:131) ==6742== by 0x8048377: f (example.c:5) ==6742== by 0x80483AC: main (example.c:12) ==6742== ==6742== LEAK SUMMARY: ==6742== definitely lost: 40 bytes in 1 blocks. ==6742== possibly lost: 0 bytes in 0 blocks. ==6742== still reachable: 0 bytes in 0 blocks. ==6742== suppressed: 0 bytes in 0 blocks. ==6742== Reachable blocks (those to which a pointer was found) are not shown. ==6742== To see them, rerun with: --show-reachable=yes 上面的C程序存在两个错误：1. 数组下标越界；2. 分配的内存没有释放，存在内存泄露的问题。 对于错误1，看Valgrind的调试信息片断 ==6742== Invalid write of size 4 ==6742== at 0x8048384: f (example.c:6) ==6742== by 0x80483AC: main (example.c:12) ==6742== Address 0x1B908050 is 0 bytes after a block of size 40 alloc'd ==6742== at 0x1B904984: malloc (vg_replace_malloc.c:131) ==6742== by 0x8048377: f (example.c:5) 对于错误2，看这个 ==6742== malloc/free: 1 allocs, 0 frees, 40 bytes allocated. ...... ==6742== 40 bytes in 1 blocks are definitely lost in loss record 1 of 1 ==6742== at 0x1B904984: malloc (vg_replace_malloc.c:131) ==6742== by 0x8048377: f (example.c:5) ==6742== by 0x80483AC: main (example.c:12) |