这是我的代码:
std::string getword()
{
std::string temp;
std::cin >> temp;
return temp;
}
Valgrind 在 std::cin >> temp 行抛出错误。
以下是询问者的 valgrind 输出:
HEAP SUMMARY:
==18490== in use at exit: 33 bytes in 1 blocks
==18490== total heap usage: 397 allocs, 396 frees, 12,986 bytes allocated
==18490==
==18490== 33 bytes in 1 blocks are possibly lost in loss record 1 of 1
==18490== at 0x4C2AF8E: operator new(unsigned long) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==18490== by 0x4EEE3B8: std::string::_Rep::_S_create(unsigned long, unsigned long, std::allocator<char> const&) (in /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.17)
==18490== by 0x4EEF127: std::string::_Rep::_M_clone(std::allocator<char> const&, unsigned long) (in /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.17)
==18490== by 0x4EEF20F: std::string::reserve(unsigned long) (in /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.17)
==18490== by 0x4EA7D14: std::basic_istream<char, std::char_traits<char> >& std::operator>><char, std::char_traits<char>, std::allocator<char> >(std::basic_istream<char, std::char_traits<char> >&, std::basic_string<char, std::char_traits<char>, std::allocator<char> >&) (in /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.17)
==18490== by 0x401681: getword() (netsim.cc:29)
==18490== by 0x401F6E: main (netsim.cc:96)
==18490==
==18490== LEAK SUMMARY:
==18490== definitely lost: 0 bytes in 0 blocks
==18490== indirectly lost: 0 bytes in 0 blocks
==18490== possibly lost: 33 bytes in 1 blocks
==18490== still reachable: 0 bytes in 0 blocks
==18490== suppressed: 0 bytes in 0 blocks
==18490==
==18490== For counts of detected and suppressed errors, rerun with: -v
==18490== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 2 from 2)
netsim.cc:96 是程序中对 getword() 的第二次调用。该代码读取
std::string network = getword();
netsim.cc:29 是 getword() 本身的代码。29号线是线
std::cin >> temp
我仍然不明白为什么会这样,但我设法解决了这个问题。我有代码
std::string s = getword();
就在上面
std::string network = getword();
我制作了 s 和 network 全局变量,不知何故问题得到了解决。
如果有人能解释为什么会这样,我将不胜感激。