I can get other boost libraries to work in Eclipse C++ plugin, but have problem in boost thread. What's the problem?
#include <boost/thread/thread.hpp>
#include <iostream>
using namespace std;
void hello()
{
cout<<"hello world!"<<endl;
}
int main()
{
boost::thread thrd(&hello);
cout<<"Just a test!"<<endl;
return 0;
}
Error messages:
** Rebuild of configuration Debug for project Hello **
Internal Builder is used for build **
g++ -IC:\boost_1_47_0 -O0 -g3 -Wall -c -fmessage-length=0 -osrc\hello.o ..\src\hello.cpp
In file included from C:\boost_1_47_0/boost/thread/win32/thread_data.hpp:12,
from C:\boost_1_47_0/boost/thread/thread.hpp:15,
from ..\src\hello.cpp:1:
C:\boost_1_47_0/boost/thread/win32/thread_heap_alloc.hpp:59: warning: inline function 'void* boost::detail::allocate_raw_heap_memory(unsigned int)' declared as dllimport: attribute ignored
C:\boost_1_47_0/boost/thread/win32/thread_heap_alloc.hpp:69: warning: inline function 'void boost::detail::free_raw_heap_memory(void*)' declared as dllimport: attribute ignored
g++ -LC:\boost_1_47_0\stage\lib -oHello.exe src\hello.o -lboost_filesystem-mgw46-mt-d-1_47 -lboost_regex-mgw46-mt-1_47 -lboost_system-mgw46-mt-1_47 -lboost_thread-mgw46-mt-1_47 -lboost_date_time-mgw46-mt-1_47
src\hello.o: In function `main':
C:\Users\cmin\workspace\Hello\Debug/../src/hello.cpp:15: undefined reference to `_imp___ZN5boost6threadD1Ev'
C:\Users\cmin\workspace\Hello\Debug/../src/hello.cpp:15: undefined reference to `_imp___ZN5boost6threadD1Ev'
src\hello.o: In function `thread<void (*)()>':
C:/boost_1_47_0/boost/thread/detail/thread.hpp:204: undefined reference to `_imp___ZN5boost6thread12start_threadEv'
collect2: ld returned 1 exit status
Build error occurred, build is stopped
Time consumed: 1044 ms.
Related
I'm trying to compile a DLIB example: http://dlib.net/image_ex.cpp.html
and I copied it word-for-word:
#include <dlib/gui_widgets.h>
#include <dlib/image_io.h>
#include <dlib/image_transforms.h>
#include <fstream>
using namespace std;
using namespace dlib;
// ----------------------------------------------------------------------------
int main(int argc, char** argv)
{
try
{
// make sure the user entered an argument to this program
if (argc != 2)
{
cout << "error, you have to enter a BMP file as an argument to this program" << endl;
return 1;
}
And I used this command:
g++ dlib1.cpp -o dlib1 -std=c++11 -O3 -I ~/Packages/dlib/ -lpthread -lX11 -ljpeg -lpng -DDLIB_JPEG_SUPPORT -DDLIB_PNG_SUPPORT
And despite that command working fine months ago: [Can't include the JPEG_SUPPORT headers in a dlib cpp file ] this time, it gave me hundreds of errors:
dlibTest-0.cpp:(.text._ZNK4dlib10png_loader9get_imageINS_7array2dINS_9rgb_pixelENS_33memory_manager_stateless_kernel_1IcEEEEEEvRT_[_ZNK4dlib10png_loader9get_imageINS_7array2dINS_9rgb_pixelENS_33memory_manager_stateless_kernel_1IcEEEEEEvRT_]+0x7e): undefined reference to `dlib::png_loader::is_gray() const'
dlibTest-0.cpp:(.text._ZNK4dlib10png_loader9get_imageINS_7array2dINS_9rgb_pixelENS_33memory_manager_stateless_kernel_1IcEEEEEEvRT_[_ZNK4dlib10png_loader9get_imageINS_7array2dINS_9rgb_pixelENS_33memory_manager_stateless_kernel_1IcEEEEEEvRT_]+0x94): undefined reference to `dlib::png_loader::is_gray() const'
dlibTest-0.cpp:(.text._ZNK4dlib10png_loader9get_imageINS_7array2dINS_9rgb_pixelENS_33memory_manager_stateless_kernel_1IcEEEEEEvRT_[_ZNK4dlib10png_loader9get_imageINS_7array2dINS_9rgb_pixelENS_33memory_manager_stateless_kernel_1IcEEEEEEvRT_]+0xaa): undefined reference to `dlib::png_loader::is_graya() const'
dlibTest-0.cpp:(.text._ZNK4dlib10png_loader9get_imageINS_7array2dINS_9rgb_pixelENS_33memory_manager_stateless_kernel_1IcEEEEEEvRT_[_ZNK4dlib10png_loader9get_imageINS_7array2dINS_9rgb_pixelENS_33memory_manager_stateless_kernel_1IcEEEEEEvRT_]+0xd0): undefined reference to `dlib::png_loader::get_row(unsigned int) const'
dlibTest-0.cpp:(.text._ZNK4dlib10png_loader9get_imageINS_7array2dINS_9rgb_pixelENS_33memory_manager_stateless_kernel_1IcEEEEEEvRT_[_ZNK4dlib10png_loader9get_imageINS_7array2dINS_9rgb_pixelENS_33memory_manager_stateless_kernel_1IcEEEEEEvRT_]+0x176): undefined reference to `dlib::png_loader::get_row(unsigned int) const'
dlibTest-0.cpp:(.text._ZNK4dlib10png_loader9get_imageINS_7array2dINS_9rgb_pixelENS_33memory_manager_stateless_kernel_1IcEEEEEEvRT_[_ZNK4dlib10png_loader9get_imageINS_7array2dINS_9rgb_pixelENS_33memory_manager_stateless_kernel_1IcEEEEEEvRT_]+0x1ce): undefined reference to `dlib::png_loader::is_graya() const'
What exactly is going wrong here?
Some of the samples need a command line such as ...
g++ -std=c++11 -O3 -I.. ../dlib/all/source.cpp -lpthread -lX11 example_program_name.cpp
I guess source.cpp is a "library as cpp code" link : dlib compile
I have created a simple C++ application. I can compile it, and it works fine. But now I need to load the library dynamically, and I have added dlfnc.h to my project and added some more code:
#include <iostream>
#include <dlfcn.h>
void *mylib;
int eret;
using namespace std;
int main() {
mylib = dlopen("mylib.so", RTLD_LOCAL | RTLD_LAZY);
eret = dlclose(mylib);
cout << "!!!Hello, World!!!" << endl; // Prints !!!Hello, World!!!
return 0;
}
Compiling:
cd ~/workspace/LinuxGcc/src
g++ LinuxGcc.cpp
And I got a compilation error:
/tmp/ccxTLiGY.o: In function `main':
LinuxGcc.cpp:(.text+0xf): undefined reference to `dlopen'
LinuxGcc.cpp:(.text+0x25): undefined reference to `dlclose'
collect2: error: ld returned 1 exit status
dlfcn.h exist in /usr/include/.
Where is the problem?
From dlopen(3):
Link with -ldl.
so
g++ LinuxGcc.cpp -ldl
will be OK.
The solution is very simple. Add the -ldl flag for linking.
In case of the Bazel build system, linkopts = ['-ldl'].
I am trying to define a macro for the source file from the command line on an ubuntu system using the -D flag .
The source file is:
#include<iostream>
using namespace std;
int factorial(int n){
if(n!=1){
return(n * factorial(n-1));
}
else return 1;
#ifdef DEEPAK
cout<<"hello"<<endl;
#endif
}
int main()
{
factorial(4);
return(0);
}
The command I am typing is:
gcc -Wall -DDEEPAK factorial.cpp -o main
BUT, I am getting the error:
/tmp/cc4Ii5l2.o: In function `__static_initialization_and_destruction_0(int, int)':
factorial.cpp:(.text+0x63): undefined reference to `std::ios_base::Init::Init()'
factorial.cpp:(.text+0x72): undefined reference to `std::ios_base::Init::~Init()'
collect2: error: ld returned 1 exit status
Any help would be deeply appreciated. Thanks.
You should use g++ instead of gcc in the command, because gcc doesn't link to the C++ STL by default, and hence it gives an undefined reference to std::ios_base.
g++ -Wall -DDEEPAK factorial.cpp -o main
Here's my code. I'm just testing Boost::process so I'll be able to use it if/when I need to. I don't know why I'm getting the linking error that I am getting. I'm a rather novice C++ programmer. I know the concepts, but I make frequent errors in practice and am bad at debugging. I appreciate any help I can get with this.
#include<iostream>
#include<boost/process.hpp>
#include<boost/iostreams/device/file_descriptor.hpp>
namespace bp = ::boost::process;
namespace bpi = ::boost::process::initializers;
namespace bio = ::boost::iostreams;
int main(int argc, char *argv[])
{
bp::pipe p = bp::create_pipe();
bio::file_descriptor_sink sink(p.sink, bio::close_handle);
bp::execute(
bpi::run_exe("/usr/bin/ls"),
bpi::bind_stdout(sink)
);
return(0);
}
And here is my error…
/tmp/cc7cmrV8.o: In function `main':
test.cpp:(.text+0x2b): undefined reference to `boost::iostreams::file_descriptor_sink::file_descriptor_sink(int, boost::iostreams::file_descriptor_flags)'
/tmp/cc7cmrV8.o: In function `boost::process::posix::initializers::bind_stdout::bind_stdout(boost::iostreams::file_descriptor_sink const&)':
test.cpp:(.text._ZN5boost7process5posix12initializers11bind_stdoutC2ERKNS_9iostreams20file_descriptor_sinkE[_ZN5boost7process5posix12initializers11bind_stdoutC5ERKNS_9iostreams20file_descriptor_sinkE]+0x2b): undefined reference to `boost::iostreams::file_descriptor_sink::file_descriptor_sink(boost::iostreams::file_descriptor_sink const&)'
/tmp/cc7cmrV8.o: In function `void boost::process::posix::initializers::bind_stdout::on_exec_setup<boost::process::posix::executor>(boost::process::posix::executor&) const':
test.cpp:(.text._ZNK5boost7process5posix12initializers11bind_stdout13on_exec_setupINS1_8executorEEEvRT_[_ZNK5boost7process5posix12initializers11bind_stdout13on_exec_setupINS1_8executorEEEvRT_]+0x18): undefined reference to `boost::iostreams::file_descriptor::handle() const'
collect2: error: ld returned 1 exit status
Platform: Linux 64-bit
Boost: 1.55 (installed via pacman)
Boost::process: 0.5
Compile command: g++ -Wall test.cpp -o spegh.elf -lboost_system
A simple search threw me at -This-.
Seeing you posted your compile command, I'm guessing you are simply missing -lboost_iostreams in your linker settings.
I am just trying to make a vector, but it gives me a huge error and I am following a working example from my other project. The code:
#include <stdio.h>
#include <stdlib.h>
#include <vector>
using namespace std;
struct organism {
bool One;
bool Two;
};
std::vector<organism> organisms;
int main() {
printf("Content-type: text/html\n\n");
printf("TEST");
printf(getenv("QUERY_STRING"));
return 0;
}
The error:
> "make"
C:/MinGW/bin/gcc.exe -o build/e2.exe source/main.cpp
C:\Users\Stephen\AppData\Local\Temp\ccc0a0w2.o:main.cpp:(.text$_ZN9__gnu_cxx13new_allocatorI8organismE10deallocateEPS1_j[__gnu_cxx::new_allocator<organism>::deallocate(organism*, unsigned int)]+0xd): undefined reference to `operator delete(void*)'
C:\Users\Stephen\AppData\Local\Temp\ccc0a0w2.o:main.cpp:(.eh_frame$_ZNSt12_Vector_baseI8organismSaIS0_EED2Ev+0x13): undefined reference to `__gxx_personality_v0'
C:\Users\Stephen\AppData\Local\Temp\ccc0a0w2.o:main.cpp:(.eh_frame$_ZNSt6vectorI8organismSaIS0_EED1Ev+0x13): undefined reference to `__gxx_personality_v0'
collect2: ld returned 1 exit status
"make": *** [build] Error 1
> Process Exit Code: 2
> Time Taken: 00:01
I can compile it if I comment out std::vector<organism> organisms; but I have no clue what's wrong with that line. It's exactly the same in my other project, which compiles fine.
You need to compile with g++.exe instead of gcc.exe so that it will know it needs to link with the C++ library.