Cannot compile

[El_Professor]

Hello, I started a small project. I need to use an external library (.a).

.pro

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = OgameBot
TEMPLATE = app

# The following define makes your compiler emit warnings if you use
# any feature of Qt which has been marked as deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \
        main.cpp \
        mainwindow.cpp

HEADERS += \
        mainwindow.h

FORMS += \
        mainwindow.ui



win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../libRequests/release/ -lRequests
else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../libRequests/debug/ -lRequests
else:unix: LIBS += -L$$PWD/../libRequests/ -lRequests

INCLUDEPATH += $$PWD/../libRequests
DEPENDPATH += $$PWD/../libRequests

win32-g++:CONFIG(release, debug|release): PRE_TARGETDEPS += $$PWD/../libRequests/release/libRequests.a
else:win32-g++:CONFIG(debug, debug|release): PRE_TARGETDEPS += $$PWD/../libRequests/debug/libRequests.a
else:win32:!win32-g++:CONFIG(release, debug|release): PRE_TARGETDEPS += $$PWD/../libRequests/release/Requests.lib
else:win32:!win32-g++:CONFIG(debug, debug|release): PRE_TARGETDEPS += $$PWD/../libRequests/debug/Requests.lib
else:unix: PRE_TARGETDEPS += $$PWD/../libRequests/libRequests.a

main.cpp

#include <QApplication>

#include "mainwindow.h"
#include "Request.h"

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    HTTP::Request request;

    return a.exec();
}

I just call HTTP::Request which is in the external library.

Here are the errors in the compilation:

/Library/Developer/CommandLineTools/usr/bin/clang++ -stdlib=libc++ -headerpad_max_install_names  -arch x86_64 -Wl,-syslibroot,/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk -mmacosx-version-min=10.10 -Wl,-rpath,@executable_path/Frameworks -Wl,-rpath,/Users/jordanbarbe/Qt/5.10.1/clang_64/lib -o OgameBot.app/Contents/MacOS/OgameBot main.o mainwindow.o moc_mainwindow.o   -F/Users/jordanbarbe/Qt/5.10.1/clang_64/lib -L/Users/jordanbarbe/go-workspace/Project/OgameBot/../libRequests/ -lRequests -framework QtWidgets -framework QtGui -framework QtCore -framework DiskArbitration -framework IOKit -framework OpenGL -framework AGL 
ld: warning: object file (/Users/jordanbarbe/go-workspace/Project/libRequests/libRequests.a(Request.o)) was built for newer OSX version (10.13) than being linked (10.10)
ld: warning: object file (/Users/jordanbarbe/go-workspace/Project/libRequests/libRequests.a(Headers.o)) was built for newer OSX version (10.13) than being linked (10.10)
ld: warning: object file (/Users/jordanbarbe/go-workspace/Project/libRequests/libRequests.a(Response.o)) was built for newer OSX version (10.13) than being linked (10.10)
Undefined symbols for architecture x86_64:
  "_curl_easy_cleanup", referenced from:
      HTTP::Request::~Request() in libRequests.a(Request.o)
      HTTP::Request::~Request() in libRequests.a(Request.o)
  "_curl_easy_getinfo", referenced from:
      HTTP::Request::perform(HTTP::Response&) in libRequests.a(Request.o)
  "_curl_easy_init", referenced from:
      HTTP::Request::Request() in libRequests.a(Request.o)
      HTTP::Request::Request() in libRequests.a(Request.o)
  "_curl_easy_perform", referenced from:
      HTTP::Request::perform(HTTP::Response&) in libRequests.a(Request.o)
  "_curl_easy_reset", referenced from:
      HTTP::Request::Request() in libRequests.a(Request.o)
      HTTP::Request::curlReset() in libRequests.a(Request.o)
      HTTP::Request::Request() in libRequests.a(Request.o)
      HTTP::Request::get(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in libRequests.a(Request.o)
      HTTP::Request::get(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, HTTP::Headers const&) in libRequests.a(Request.o)
      HTTP::Request::post(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in libRequests.a(Request.o)
      HTTP::Request::post(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, HTTP::Headers const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in libRequests.a(Request.o)
      ...
  "_curl_easy_setopt", referenced from:
      HTTP::Request::Request() in libRequests.a(Request.o)
      HTTP::Request::curlReset() in libRequests.a(Request.o)
      HTTP::Request::Request() in libRequests.a(Request.o)
      HTTP::Request::get(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in libRequests.a(Request.o)
      HTTP::Request::get(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, HTTP::Headers const&) in libRequests.a(Request.o)
      HTTP::Request::post(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in libRequests.a(Request.o)
      HTTP::Request::post(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, HTTP::Headers const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in libRequests.a(Request.o)
      ...
  "_curl_easy_strerror", referenced from:
      HTTP::Request::perform(HTTP::Response&) in libRequests.a(Request.o)
  "_curl_slist_append", referenced from:
      HTTP::Headers::set(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in libRequests.a(Headers.o)
      HTTP::Headers::set(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in libRequests.a(Headers.o)
  "_curl_slist_free_all", referenced from:
      HTTP::Headers::~Headers() in libRequests.a(Headers.o)
      HTTP::Headers::clear() in libRequests.a(Headers.o)
      HTTP::Headers::~Headers() in libRequests.a(Headers.o)
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [OgameBot.app/Contents/MacOS/OgameBot] Error 1

here is the library I'm trying to use: lib request

Thank you for your future answer.

[Edit ~aha_1980: fixed link]

[aha_1980]

@El_Professor said in Cannot compile:

I'm no Mac user, but these lines looks suspicious to me:

ld: warning: object file (/Users/jordanbarbe/go-workspace/Project/libRequests/libRequests.a(Request.o)) was built for newer OSX version (10.13) than being linked (10.10)
ld: warning: object file (/Users/jordanbarbe/go-workspace/Project/libRequests/libRequests.a(Headers.o)) was built for newer OSX version (10.13) than being linked (10.10)
ld: warning: object file (/Users/jordanbarbe/go-workspace/Project/libRequests/libRequests.a(Response.o)) was built for newer OSX version (10.13) than being linked (10.10)

ld: symbol(s) not found for architecture x86_64

Did you get the library pre-compiled? From where? Can you build it yourself?

[El_Professor]

Hi, yes I compiled the library well before. I have my request.a file and 3 header files. I added the library via Qt with a right click on the project then "add a new library" .
So I was looking for the library in my computer in another folder in Qt. I selected external library.

thanks you

[aha_1980]

@El_Professor said in Cannot compile:

Hi, yes I compiled the library well before.

Hmm, so why does the linker complains:

ld: warning: object file [..] was built for newer OSX version (10.13) than being linked (10.10)

Maybe a Mac user can help you more in that regard.

[El_Professor]

I don't know exactly. I only cloned the above mentioned repository. and then made a Make in this repository which directly creates a libRequests.a file for me.

[aha_1980]

@El_Professor

It seems that library handles HTTP requests. Any reason you don't use Qt's QNetworkAccessManager?

[El_Professor]

I don't know. I thought we couldn't deal with it?

thanks you for reply

[aha_1980]

@El_Professor So what do you want to do exactly?

[El_Professor]

I'm learning. So I try to get a web page for example from a game and then connect to that game via the c++/Qt code.

[aha_1980]

@El_Professor so why can't you use QNetworkAccessManager?

[El_Professor]

In fact a friend explained to me that he was using this library I thought I would take the same one. I forgot Qt can do it. Thank you for your response. I already started my program with this class. And I can do the same thing with librequest for lib.a.
sorry for the inconvenience