Question

我有大约350行代码，我正在解析xml文件并使用C ++创建另外两张代码。

添加最后2或3个函数后，我开始出现内存错误，

信号：SIGSEGV（分段故障）

删除它们并没有解决错误所以我肯定编辑了其他内容。我在网上搜索了一下valgrind，发现了我无法翻译的错误。

根据valgrind手册，我必须从下到上检查，以便按照最后一个，

== 7276 == 4个块中的4,064个字节肯定会丢失在54的丢失记录52中   == 7276 ==在0x4C2DB8F：malloc（在/usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
  == 7276 == by 0x456BDD：??? （在/ usr / bin / g ++ - 5中）
  == 7276 == by 0x4EC260D：_obstack_begin（obstack.c：176）
  == 7276 == by 0x456FCE：??? （在/ usr / bin / g ++ - 5中）
  == 7276 == by 0x43BA49：??? （在/ usr / bin / g ++ - 5中）
  == 7276 == by 0x43BAC0：??? （在/ usr / bin / g ++ - 5中）
  == 7276 == by 0x4E5A82F :(主要）（libc-start.c：291）

第291行是以下代码中的追加行

if (vlan_ether)
sprintf(cConfStr, "**.Switch%ld.eth[%d].queue.VlanClassifier = true\n", srcindex + 1, portno);
else if (!vlan_ether)
sprintf(cConfStr, "**.Switch%ld.eth[%d].queue.etherType = false\n", srcindex + 1, portno);
else
cout << "Switch" << srcindex + 1 << "port# " << portno << " Classifier is not specified." << endl;
confStr.append(string(cConfStr));

删除上面的行没有做任何更改，而第176行是注释，所以我犹豫说valgrind没有显示错误行。

所以我不确定在代码中我的问题中向您展示了什么。我仍然确定它应该与字符串和字符用法相关，其中我多次使用它们。

char cNedStr[600];
char cConfStr[600];

sprintf(cConfStr, "%d ", intervalvector[q]);
confStr.append(string(cConfStr));

Valgrind结果如下，

amr@amr-PC:~$ valgrind --leak-check=yes  g++ main.cpp pugixml.cpp headers.h -Wall -std=c++11

修改

amr@amr-PC:~/ClionProjects/converter$ valgrind ./a.out
==7624== Memcheck, a memory error detector
==7624== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==7624== Using Valgrind-3.11.0 and LibVEX; rerun with -h for copyright info
==7624== Command: ./a.out
==7624== Invalid free() / delete / delete[] / realloc()
==7624==    at 0x4C2F24B: operator delete(void*) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==7624==    by 0x5714FF7: __run_exit_handlers (exit.c:82)
==7624==    by 0x5715044: exit (exit.c:104)
==7624==    by 0x56FB836: (below main) (libc-start.c:325)
==7624==  Address 0x35663a37323a6536 is not stack'd, malloc'd or (recently) free'd
==7624== 
==7624== 
==7624== HEAP SUMMARY:
==7624==     in use at exit: 72,704 bytes in 1 blocks
==7624==   total heap usage: 525 allocs, 525 frees, 214,887 bytes allocated
==7624== 
==7624== LEAK SUMMARY:
==7624==    definitely lost: 0 bytes in 0 blocks
==7624==    indirectly lost: 0 bytes in 0 blocks
==7624==      possibly lost: 0 bytes in 0 blocks
==7624==    still reachable: 72,704 bytes in 1 blocks
==7624==         suppressed: 0 bytes in 0 blocks
==7624== Rerun with --leak-check=full to see details of leaked memory
==7624== 
==7624== For counts of detected and suppressed errors, rerun with: -v
==7624== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 0 from 0)

Answer 1

首先编译，没有头文件，（默认输出为a.out）：

g++ main.cpp pugixml.cpp -Wall -std=c++11

然后使用valgrind检查：

valgrind --leak-check=yes ./a.out

其他评论：

您可以考虑将以下标志添加到g ++：

-Wextra（更多警告）
-pedantic（关闭扩展并生成更多警告）
-g（调试符号）
-O3（最大化优化，不推荐用于调试！）

使用valgrind分析进行c ++ char内存泄漏

1 个答案: