【发布时间】:2012-04-01 19:36:51
【问题描述】:
已解决
我不得不删除旧的目标文件并重建整个项目来解决问题。不幸的是,我不知道我收到此错误的真正原因。
可能是一些错误放置的包含语句,或者可能在我同时删除的 accountsContainer.h 的类声明中存在定义。
我正在尝试编译一个小型 C/C++ 应用程序,但遇到了链接问题:
确切的错误是这样的:
make all
g++ -g -Wall -fmessage-length=0 -I "Z:/SRS/Verwaltung/EDV/Marcus EDV/Programmierung/link libraries/c++/curl-7.24.0/include/curl/" -c -o accountsContainer.o accountsContainer.cpp
g++ -o libcurl.exe signatureUpdater.o accountsContainer.o network.o registry.o emailAccount.o filesystem.o libcurl.o "Z:/SRS/Verwaltung/EDV/Marcus EDV/Programmierung/link libraries/c++/curl-7.24.0/lib/libcurl.dll"
accountsContainer.o: In function `accountsContainer':
G:\#1Arbeit\htdocs\libcurl/accountsContainer.cpp:11: multiple definition of `accountsContainer::accountsContainer()'
signatureUpdater.o:G:\#1Arbeit\htdocs\libcurl/accountsContainer.h:13: first defined here
collect2: ld returned 1 exit status
make: *** [libcurl.exe] Error 1
我不明白这个错误来自哪里。我已经在互联网上对“多重定义”-错误进行了一些研究。 这是我所知道的: 我认为您可以根据需要多次声明类或函数,但我只能定义一次。
这就是我所做的: 我在 accountsContainer.cpp 中定义了类构造函数“accountsContainer::accountsContainer(){...}”,它从未包含在任何地方,但只能使用我的 make-file 编译到 accountsContainer.o accountsContainer.h 包含类的声明
但是为什么链接器会抱怨在头文件中定义了accountsContainer::accountsContainer(){...}?
这些是我的文件: “accountsContainer.h”
/*
* accountsContainer.h
*
* Created on: 16.03.2012
* Author: Admin
*/
#ifndef ACCOUNTSCONTAINER_H_
#define ACCOUNTSCONTAINER_H_
#include "emailAccount.h"
#include <string>
#include <iostream>
#include <algorithm>
class accountsContainer {
public:
const static int MAX_ACCOUNTS = 50;
private:
emailAccount srsAccounts[],emailAccounts[];
//can only be initalized in the constructor
int nAccounts;
int nSrsAccounts;
//methods
private:
void emailToLowerCase();
void findSrsAccounts();
public:
accountsContainer();
void printSrsAccounts();
emailAccount & getSrsAccount(int);
};
#endif /* ACCOUNTSCONTAINER_H_ */
“accountsContainer.cpp”
/*
* accountsContainer.cpp
*
* Created on: 16.03.2012
* Author: Admin
*/
#include "accountsContainer.h"
#include "signatureUpdater.h"
accountsContainer::accountsContainer() {
//init variables
nAccounts = 0;
nSrsAccounts = 0;
/*
* read email Accounts from registry and save them to the srsAccounts Array
*/
signatureUpdater::reg.getEmailAccounts(srsAccounts,MAX_ACCOUNTS);
//make all e-mail adresses lower case
emailToLowerCase();
findSrsAccounts();
}
void accountsContainer::printSrsAccounts(){
string locS;
for(int i=0;i < nSrsAccounts;i++){
wcout << L"Account " << i << L" : " << srsAccounts[i].displayName <<endl;
wcout << L"Name: " << srsAccounts[i].accName.c_str() << endl;
wcout << L"E-Mail:" << srsAccounts[i].email.c_str() << endl << endl;
}
}
emailAccount & accountsContainer::getSrsAccount(int i){
return srsAccounts[i];
}
void accountsContainer::emailToLowerCase(){
wstring s;
for(int i=0; i < nAccounts; i++){
s = emailAccounts[i].email;
std::transform(s.begin(), s.end(), s.begin(), std::ptr_fun<int,int>(std::tolower));
emailAccounts[i].email = s;
}
}
void accountsContainer::findSrsAccounts(){
/*
* resets Number of SRS accounts
* then iterates all e-mail accounts
* and searches for domain srsonline.de
* in lowercase!
*/
size_t found;
wstring emailAdr;
nSrsAccounts = 0;
for(int i=0;i<nAccounts;i++){
emailAdr=emailAccounts[i].email;
found = emailAdr.rfind(L"srsonline.de");
if(found != string::npos && (emailAdr.length()-found) == 12){
/*
wcout << L"für E-mail Konto: " << emailAdr << endl;
cout << "srsonline.de found at: " << found << endl;
*/
// copy SRS Accounts to srsAccounts array
srsAccounts[nSrsAccounts] = emailAccounts[i];
nSrsAccounts++;
}
}
}
这就是我的makefile:
CXXFLAGS = -g -Wall -fmessage-length=0 -I "Z:/SRS/Verwaltung/EDV/Marcus EDV/Programmierung/link libraries/c++/curl-7.24.0/include/curl/" # -O2 no performance improvement because of debugging!
OBJS = signatureUpdater.o accountsContainer.o network.o registry.o emailAccount.o filesystem.o libcurl.o
LIBS = "Z:/SRS/Verwaltung/EDV/Marcus EDV/Programmierung/link libraries/c++/curl-7.24.0/lib/libcurl.dll"
TARGET = libcurl.exe
$(TARGET): $(OBJS)
$(CXX) -o $(TARGET) $(OBJS) $(LIBS)
all: $(TARGET)
clean:
rm -f $(OBJS) $(TARGET)
我希望问题不是来自糟糕的程序架构/设计 谢谢你的帮助!
【问题讨论】:
-
你重建项目了吗?
-
你的意思是如果我做了 make clean 并尝试再次编译整个项目?是的,我这样做了,但错误仍然存在。
-
您确定 signatureUpdater.o 被删除并重建了吗?因为您的 .h 文件的第 13 行是 #include
这与您的课程毫无关系。 -
你是对的!看来我的 rm.bat 包含错误。删除所有手动正确链接的目标文件后。谢谢!
标签: c++ linker definition