Help using PCRE in C++

问题:

this is my first time trying to build a C++ application, so I'm kind of lost. I've looked at some examples but I still dont really know what's wrong.

#include <iostream>
#include <stdio.h>
#include <windows.h>
#include <pcrecpp.h>
#include <string>
#include <cstring>

using namespace std;

int main()
{
    char title[256];
    char url[256];
    string song, diff;
    HWND hwnd = FindWindow("WindowsForms10.Window.8.app.0.33c0d9d", NULL);
    GetWindowTextA(hwnd, title, 255);
    pcrecpp::RE re("^osu!  - (.*) \\[(.*)\\] \\[[|-]{21}\\]$");
    re.FullMatch(title, &song, &diff);
    sprintf(url, "xfire:game_stats?game=%s&%s=%s&%s=%s", "osu", "Playing", song.c_str(), "Difficulty", diff.c_str());
    ShellExecute(NULL, NULL, url, NULL, NULL, SW_SHOWDEFAULT);
    return 0;
}

When I try to compile, I get the following compiler errors

obj\Debug\main.o||In function 'main':| C:\Users\Zeffy\Desktop\osu-gamestats\main.cpp|18|undefined reference to '_imp___ZN7pcrecpp2RE6no_argE'| C:\Users\Zeffy\Desktop\osu-gamestats\main.cpp|18|undefined reference to '_imp___ZN7pcrecpp2RE6no_argE'| C:\Users\Zeffy\Desktop\osu-gamestats\main.cpp|18|undefined reference to '_imp___ZN7pcrecpp2RE6no_argE'| C:\Users\Zeffy\Desktop\osu-gamestats\main.cpp|18|undefined reference to '_imp___ZN7pcrecpp2RE6no_argE'| C:\Users\Zeffy\Desktop\osu-gamestats\main.cpp|18|undefined reference to '_imp___ZN7pcrecpp2RE6no_argE'| obj\Debug\main.o:C:\Users\Zeffy\Desktop\osu-gamestats\main.cpp|18|more undefined references to '_imp___ZN7pcrecpp2RE6no_argE' follow| obj\Debug\main.o||In function 'main':| C:\Users\Zeffy\Desktop\osu-gamestats\main.cpp|18|undefined reference to '_imp___ZNK7pcrecpp2RE9FullMatchERKNS_11StringPieceERKNS_3ArgES6_S6_S6_S6_S6_S6_S6_S6_S6_S6_S6_S6_S6_S6_S6_'| C:\Users\Zeffy\Desktop\osu-gamestats\main.cpp|17|undefined reference to '_imp___ZN7pcrecpp2RED1Ev'| C:\Users\Zeffy\Desktop\osu-gamestats\main.cpp|17|undefined reference to '_imp___ZN7pcrecpp2RED1Ev'| obj\Debug\main.o||In function 'Arg':| C:\MinGW\msys\1.0\local\include\pcrecpparg.h|89|undefined reference to '_imp___ZN7pcrecpp3Arg12parse_stringEPKciPv'| obj\Debug\main.o||In function 'RE':| C:\MinGW\msys\1.0\local\include\pcrecpp.h|493|undefined reference to '_imp___ZN7pcrecpp2RE4InitERKSsPKNS_10RE_OptionsE'| ||=== Build finished: 11 errors, 0 warnings ===|

回答1:

_imp___ZN7pcrecpp2RE6no_argE is a mangled name. Since it contains the parts pcrecpp and no_arg, I suspect that the problem is that you fail to link against Pcrecpp. Therefore, the no_arg symbol is not defined.