undefined reference to `check(std::string const&)' while linking - c++

Question

I have some "simple" code in C++ to connect to a MySQL database (which is localhost, btw).
#include <stdlib.h>
#include <iostream>
#include "mysql/include/mysql/jdbc.h"
using namespace sql;
int main() {
std::cout << "Test"<< std::endl;
try {
sql::Driver *myDriver;
sql::Connection *myConn;
sql::Statement *myStmt;
sql::ResultSet *myRes;
myDriver = sql::mysql::get_mysql_driver_instance();
myConn = myDriver ->connect("tcp://127.0.0.1", "root", "");
myConn->setSchema("root");
myStmt = myConn->createStatement();
myRes = myStmt->executeQuery("SELECT 'Hello World' AS _message");
while (myRes->next()) {
std::cout << myRes->getString("_message") << std::endl;
}
delete myRes;
delete myStmt;
delete myConn;
} catch (sql::SQLException &e) {
std::cout << "Filed connect to Database" << std::endl;
std::cout << "Error: " << e.what() << std::endl;
std::cout << "Error code: " << e.getErrorCode() << std::endl;
}
}
The file jdbc.h is just a lot of different #include for header files.
I use 2 commands to compile:
g++ -c -Wall -I/usr/include/cppconn connect.cpp -o connect.o and
g++ -lm -L/usr/lib/x86_64-linux-gnu -lmysqlcppconn connect.o -o connect
Which produced this linking error:
/usr/bin/ld: connect.o: in function "check_lib()':
connect.cpp:(.text+0x2c): undefined reference to `check(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)"
/usr/bin/ld: connect.cpp:(.text+0x77): undefined reference to "check(std::map<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::less<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > > const&)"
/usr/bin/ld: connect.o: in function `sql::mysql::get_driver_instance_by_name(char const*)':
connect.cpp:(.text+0xfa): undefined reference to "sql::mysql::_get_driver_instance_by_name(char const*)"
collect2: error: ld returned 1 exit status
Which I kinda resolved using this answer: https://stackoverflow.com/a/33395489/14814564 , essentially by putting #define _GLIBCXX_USE_CXX11_ABI 0 at the top of the file, which after compilation, produces this linking error:
/usr/bin/ld: connect.o: in function "check_lib()':
connect.cpp:(.text+0x2c): undefined reference to "check(std::string const&)'
/usr/bin/ld: connect.cpp:(.text+0x77): undefined reference to "check(std::map<std::string, std::string, std::less<std::string>, std::allocator<std::pair<std::string const, std::string> > > const&)'
/usr/bin/ld: connect.o: in function `sql::mysql::get_driver_instance_by_name(char const*)':
connect.cpp:(.text+0xfa): undefined reference to "sql::mysql::_get_driver_instance_by_name(char const*)'
collect2: error: ld returned 1 exit status
Why does this linking error keep popping up and how do I resolve it?

Answer 1

I had the same problem, I solved it by building a Makefile`
MYSQL_CONCPP_DIR = ./mysql
CPPFLAGS=-I $(MYSQL_CONCPP_DIR)/include/mysql -L $(MYSQL_CONCPP_DIR)/lib64
LDLIBS=-lmysqlcppconn
CXXFLAGS=-std=c++11
out.exe:test.cpp
g++ test.cpp ${LDLIBS} ${CXXFLAGS} ${CPPFLAGS} -o out.exe
You have there
#include "mysql/include/mysql/jdbc.h"
In my case include needs to be done like this`
#include <jdbc.h>