centos下使用hash_map报错

hsdrhsdr

项目用到hash_map，在编译时出现下面错误：
n file included from /usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../include/c++/4.4.7/ext/hash_map:62,
                 from /root/dev/src/network/EventList.h:13,
                 from /root/dev/src/network/EventList.cpp:9:
/usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../include/c++/4.4.7/backward/hashtable.h: In member function ‘size_t __gnu_cxx::hashtable<_Val, _Key, _HashFcn, _ExtractKey, _EqualKey, _Alloc>::_M_bkt_num_key(const _Key&, size_t) const [with _Val = std::pair<const std::basic_string<char, std::char_traits<char>, std::allocator<char> >, event*>, _Key = std::basic_string<char, std::char_traits<char>, std::allocator<char> >, _HashFcn = __gnu_cxx::hash<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, _ExtractKey = std::_Select1st<std::pair<const std::basic_string<char, std::char_traits<char>, std::allocator<char> >, event*> >, _EqualKey = std::equal_to<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, _Alloc = std::allocator<event*>]’:
/usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../include/c++/4.4.7/backward/hashtable.h:582:   instantiated from ‘size_t __gnu_cxx::hashtable<_Val, _Key, _HashFcn, _ExtractKey, _EqualKey, _Alloc>::_M_bkt_num_key(const _Key&) const [with _Val = std::pair<const std::basic_string<char, std::char_traits<char>, std::allocator<char> >, event*>, _Key = std::basic_string<char, std::char_traits<char>, std::allocator<char> >, _HashFcn = __gnu_cxx::hash<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, _ExtractKey = std::_Select1st<std::pair<const std::basic_string<char, std::char_traits<char>, std::allocator<char> >, event*> >, _EqualKey = std::equal_to<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, _Alloc = std::allocator<event*>]’
/usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../include/c++/4.4.7/backward/hashtable.h:865:   instantiated from ‘size_t __gnu_cxx::hashtable<_Val, _Key, _HashFcn, _ExtractKey, _EqualKey, _Alloc>::erase(const _Key&) [with _Val = std::pair<const std::basic_string<char, std::char_traits<char>, std::allocator<char> >, event*>, _Key = std::basic_string<char, std::char_traits<char>, std::allocator<char> >, _HashFcn = __gnu_cxx::hash<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, _ExtractKey = std::_Select1st<std::pair<const std::basic_string<char, std::char_traits<char>, std::allocator<char> >, event*> >, _EqualKey = std::equal_to<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, _Alloc = std::allocator<event*>]’
/usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../include/c++/4.4.7/ext/hash_map:233:   instantiated from ‘typename __gnu_cxx::hashtable<std::pair<const _Key, _Tp>, _Key, _HashFn, std::_Select1st<std::pair<const _Key, _Tp> >, _EqualKey, _Alloc>::size_type __gnu_cxx::hash_map<_Key, _Tp, _HashFn, _EqualKey, _Alloc>::erase(const typename __gnu_cxx::hashtable<std::pair<const _Key, _Tp>, _Key, _HashFn, std::_Select1st<std::pair<const _Key, _Tp> >, _EqualKey, _Alloc>::key_type&) [with _Key = std::basic_string<char, std::char_traits<char>, std::allocator<char> >, _Tp = event*, _HashFn = __gnu_cxx::hash<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, _EqualKey = std::equal_to<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, _Alloc = std::allocator<event*>]’
/root/dev/src/network/EventList.cpp:54:   instantiated from here
/usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../include/c++/4.4.7/backward/hashtable.h:590: 错误：对‘(const __gnu_cxx::hash<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >) (const std::basic_string<char, std::char_traits<char>, std::allocator<char> >&)’的调用没有匹配
make[2]: *** [CMakeFiles/devServer.dir/src/network/EventList.cpp.o] 错误 1
make[1]: *** [CMakeFiles/devServer.dir/all] 错误 2
make: *** [all] 错误 2

---

EventList代码如下：

#include "EventList.h"
#include <string.h>
#include <stdlib.h>

EventList::EventList()
{
   
}

int EventList::set(char *type, int typeLength, event *evn)
{
    char key[64];
    memset(key, 0, 64);
    memcpy(key, evn->imei, evn->imeiLength);
    memcpy(key+evn->imeiLength, type, typeLength);
   
    std::string strKey = key;
    this->devcmdList[strKey] = evn;
   
    return 0;

}
event *EventList::get(char *type, int typeLength, char *imei, int imeiLength)
{
    char key[64];
    memset(key, 0, 64);
    memcpy(key, imei, imeiLength);
    memcpy(key+imeiLength, type, typeLength);
   
    std::string strKey = key;
    event *evn = this->devcmdList[strKey];
   
    return evn;

}
int EventList::del(char *type, int typeLength, char *imei, int imeiLength)
{
    char key[64];
    memset(key, 0, 64);
    memcpy(key, imei, imeiLength);
    memcpy(key+imeiLength, type, typeLength);
   
    std::string strKey = key;
    event *evn = this->devcmdList[strKey];
    if (evn != NULL) {
        this->devcmdList.erase(strKey);
        free(evn);
    }
    return 0;
}

一大堆错误信息，看不明白，不过在mac平台下编译却可以正常运行

myworkstation

回复 1# hsdrhsdr


加上这个试试：

1. namespace __gnu_cxx {
   
2.     template <>
   
3.         struct hash<std::string> {
   
4.             size_t operator() (const std::string& x) const {
   
5.                 return hash<const char*>()(x.c_str());
   
6.             }
   
7.         };
   
8. }

复制代码

你用的这个版本不支持直接使用std::string作为key(不能直接计算string的hash)所以需要把这个加上。