Some days ago I compiled Boost ver. 1.53.0 for VS2012. It works fine, compiles fine. Now I want to use Boost with Qt Creator. In the .pro file I've included
INCLUDEPATH += C:\boost\boost_1_53_0\ -lboost_filesystem
LIBS += C:/boost/boost_1_53_0/stage/lib/
But when I compile I get 2 errors:
:-1: error: cannot find C:/boost/boost_1_53_0/stage/lib/: Permission denied
collect2.exe:-1: error: error: ld returned 1 exit status
What should I do? I've googled but seems I'm the first with this error.
INCLUDEPATH += C:\boost\boost_1_53_0\ -lboost_filesystem
LIBS += C:/boost/boost_1_53_0/stage/lib/
Wrong.
Read this.
Solution:
INCLUDEPATH += C:/boost/boost_1_53_0/
LIBS += "-LC:/boost/boost_1_53_0/stage/lib/"
Boost has complicated library names ("libboost_filesystem-vc90-mt-1_53.lib") and in case of msvc it links them automatically.)
If you want to link additional lib, you do it like this:
LIBS += "-LMyLibraryPath" -lmylib
Where MyLibraryPath is library path, and mylib is library you want to link with.
i'm the first with this error.
The error most likely occurs because compiler tries to open directory as if it were a file or something like that.
win32 {
INCLUDEPATH += C:/Users/User/Downloads/dev/boost_1_61_0
LIBS += "-LC:/dev/Boost/lib/" \
"-Llibboost_filesystem-mgw53-mt-d-1_61.a", "-Llibboost_system-mgw53-mt-d-1_61.a", "-Llibboost_serialization-mgw53-mt-d-1_61.a" -LLIBS
}
Related
I have got an issue while integrating opencv 3.1 with Qt 5.6.
the project .pro file contains
INCLUDEPATH += C:/opencv/build/include
LIBS += -LC:/opencv/build/x64/vc14/lib
INCLUDEPATH += LIBS += -lopencv_world310
but gives undefined reference errors like:
error: undefined reference to `cv::VideoCapture::VideoCapture()
I have even tried using cmake, but it still gives the same error.
Thanks in advance for your help.
I'm trying to use the Sha512 function in openSSL but can't seem to get it to work as I get compiler errors just starting into the code. I include #include <openssl/sha.h> at the top of the .cpp file, then in the action of a button event I put just the following code below.
SHA512_CTX ctx;
SHA512_Init(&ctx);
//Will uncomment below in later if I get SHA512_Init to work
//SHA512_Update(&ctx, string, strlen(string));
//SHA512_Final(digest, &ctx);
I get a linker error telling my undefined symbols for architecture x86_64, implying the function does not exist?
I'm aware QT 5 has a hash function, but I'm limited to QT 4.8 so I can not use the cryptographic sha512 hash function available in the QT 5+ framework.
Any help is appreciated!
Used macports to install openssl
I'm using Mac OS 10.9.2
MAKE FILE
#-------------------------------------------------
#
# Project created by QtCreator 2014-06-11T20:27:49
#
#-------------------------------------------------
QT += core gui network
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
TARGET = ExchangeTab
TEMPLATE = app
LIBS += -L/usr/include/openssl -openssl
INCLUDEPATH += /usr/include/openssl
SOURCES += main.cpp\
mainwindow.cpp \
httpsocket.cpp \
cloaksend.cpp \
exchange.cpp
HEADERS += mainwindow.h \
httpsocket.h \
cloaksend.h \
exchange.h
FORMS += mainwindow.ui
RESOURCES += \
AppResources.qrc
Looking for cross platform solution please.
You need to link to the right library (openSSL)
Have a look here: How to Include OpenSSL in a Qt project
Specifically, add this to your .pro file.:
LIBS += -L/opt/local/lib/ -lcrypto
For including .h files add this line to your .pro file :
INCLUDEPATH += /opt/local/include
[1] says that the default include path will be /opt/local/include/.
LIBS += -L/usr/include/openssl -openssl
INCLUDEPATH += /usr/include/openssl
This looks incorrect. The OpenSSL libraries are libcrypto (-lcrypto) and libssl (-lssl). There is nolibopenssl(-lopenssl). Try:
LIBS += -L/usr/lib -lcrypto
INCLUDEPATH += /usr/include/openssl
But the libraries are version 0.9.8. You might consider upgrading to 1.0.1h.
$ ls /usr/lib | grep crypto
libcrypto.0.9.7.dylib
libcrypto.0.9.8.dylib
libcrypto.dylib
libk5crypto.dylib
And
$ /usr/bin/openssl version
OpenSSL 0.9.8y 5 Feb 2013
If you choose to upgrade, OpenSSL will install into /usr/local/ssl. Avoid mixing/matching version of OpenSSL with the following.
INCLUDEPATH += /usr/local/ssl/include/openssl
LIBS += /usr/local/ssl/lib/libcrypto.a
Its OK to specify objects and archives in LIBS. See How to add object files to a project in Qt.
Okay so I may have answered my own question but I will need some help understanding why it worked.
My make file was indeed the problem. I added the following 3 lines.
INCLUDEPATH += $$OPENSSL_INCLUDE_PATH
LIBS += $$join(OPENSSL_LIB_PATH,,-L,)
LIBS += -lcrypto
Then it magically compiled just fine. I found these in another project made with QT that compiled for OpenSSL.
Interestingly enough. I removed the top two lines so only the following remained. Then ran the clean on my project to be sure the code was being recompiled.
LIBS += -lcrypto
This also just 'worked' without linker errors. It looks like that is the only command I need. Question is... will that be cross platform friendly if I take this code and compile on linux or windows? That I am not sure, but this worked.
I've been attempting for the past 16 hours to attach the libusb library to a Qt project without much success. I would appreciate any input on the matter, it's getting frustrating.
The .pro file is this:
TEMPLATE = app
CONFIG += console
CONFIG -= app_bundle
CONFIG -= qt
SOURCES += main.cpp
INCLUDEPATH +=/usr/local/include/libusb-1.0
LIBS += -L/usr/local/lib -libusb-1.0.a
LIBS += -L<libusb.h>
Source code:
#include <iostream>
#include <libusb.h>
using namespace std;
int main()
{
cout << "Hello World!" << endl;
return 0;
}
Compiler output:
13:01:50: Running steps for project lallala...
13:01:50: Configuration unchanged, skipping qmake step.
13:01:50: Starting: "/usr/bin/make" -w
make: Entering directory `/Users/MAXIMUS/Documents/workspace/lallala-build-Desktop_Qt_5_0_0_clang_64bit_SDK-Debug'
/Users/MAXIMUS/Qt5.0.0/5.0.0/clang_64/bin/qmake -spec macx-g++42 CONFIG+=debug CONFIG+=x86_64 CONFIG+=declarative_debug CONFIG+=qml_debug -o Makefile ../lallala/lallala.pro
make: Leaving directory `/Users/MAXIMUS/Documents/workspace/lallala-build-Desktop_Qt_5_0_0_clang_64bit_SDK-Debug'
make: Entering directory `/Users/MAXIMUS/Documents/workspace/lallala-build-Desktop_Qt_5_0_0_clang_64bit_SDK-Debug'
g++-4.2 -headerpad_max_install_names -mmacosx-version-min=10.6 -o lallala main.o -L/usr/local/lib -libusb-1.0.a -L<libusb.h>
/bin/sh: -c: line 0: syntax error near unexpected token `newline'
/bin/sh: -c: line 0: `g++-4.2 -headerpad_max_install_names -mmacosx-version-min=10.6 -o lallala main.o -L/usr/local/lib -libusb-1.0.a -L<libusb.h> '
make: *** [lallala] Error 2
make: Leaving directory `/Users/MAXIMUS/Documents/workspace/lallala-build-Desktop_Qt_5_0_0_clang_64bit_SDK-Debug'
13:01:50: The process "/usr/bin/make" exited with code 2.
Error while building/deploying project lallala (kit: Desktop Qt 5.0.0 clang 64bit (SDK))
When executing step 'Make'
Forming my comment into a proper answer; this is not the correct syntax to use:
LIBS += -L/usr/local/lib -libusb-1.0.a
LIBS += -L<libusb.h>
The proper one would be this:
LIBS += -L/usr/local/lib -lusb-1.0
or
LIBS += -l/full/path/to/libusb-1.0.a
You can drop the second LIBS line in your initial attempt because you have already specified the path in the former, and putting an "include" statement in there would not be reasonable anyhow. So, this is what you could write for your complete .pro file:
TEMPLATE = app
CONFIG += console
CONFIG -= app_bundle
CONFIG -= qt
SOURCES += main.cpp
INCLUDEPATH +=/usr/local/include/libusb-1.0
LIBS += -L/usr/local/lib -lusb-1.0
This is not Qt specific, just generic linkage issue: -lfoo extends to $(prefix)foo$(suffix), where the prefix and suffix are figured out automatically based on the platform. That is, the prefix would be lib in your case, and suffix would be either .a or .so on Unix, probably .dylib on Mac, etc.
You may wish to look into pkg-config support if it is possible to establish. In that case, you would write something like this what we did in QtSerialPort:
CONFIG += link_pkgconfig
PKGCONFIG += libudev
Yet another option is to add the GUI through the QtCreator IDE or similar IDE that you may be using. There is an option usually in the "Linker" section to add a library. Here are two screenshots from my QtCreator:
Click on the project name on the left in the project source tree navigator, and select Add Library. Then the first screenshot will come up, and you can select the external option, and then you can see the second.
It is needless to say that you would need to run qmake after these changes to generate the corresponding Makefile on your desired platform.
Syntax is the following:
-L%LIBRARY_PATH% to make a specific path visible and
-l%LIBRARY_NAME% to link a specific library that is located in a visible path
so I guess this should work (I don't think you need the .a extension):
LIBS += -L/usr/local/lib -llibusb-1.0
and I have no idea what this would do:
LIBS += -L
so I guess I'd remove it.
Once fixed run qmake then build...
Hope it helps...
Resolved. When I add my library as a normal internal library everything is fine. What I had failed to do was use the MY_LIBRARY_EXPORT macro on some free functions defined in a namespace. Somehow I had manipulated the library import in such a way to get those functions working, but it broke in other ways as described here.
I have not been able to use a shared library using the Qt Creator wizard. I have tried with dynamic linkage, and have failed, and cannot use as a static lib either. In both cases I get an 'undefined reference to `IMP_*' error.
Here are my pro files. They are both in the same SUB_DIR parent project and the paths are correct.
Relevant parts of the library pro file:
TARGET = Prospec
TEMPLATE = lib
CONFIG += staticlib
QMAKE_CXXFLAGS += -std=c++11
DEFINES += PROSPEC_LIBRARY
The entirety of the user .pro file. (ProspecTest is a unit test project for Prospec).
#-------------------------------------------------
#
# Project created by QtCreator 2013-12-12T15:04:30
#
#-------------------------------------------------
QT += testlib
QT -= gui
TARGET = prospectest
CONFIG += console
CONFIG -= app_bundle
TEMPLATE = app
QMAKE_CXXFLAGS += -std=c++11
SOURCES += prospectest.cpp \
mltest.cpp \
convertertest.cpp \
numericitemtest.cpp
DEFINES += SRCDIR=\\\"$$PWD/\\\"
HEADERS += \
utilities.h \
mltest.h \
convertertest.h \
numericitemtest.h
win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../Prospec/release/ -lProspec
else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../Prospec/debug/ -lProspec
INCLUDEPATH += $$PWD/../Prospec/debug
DEPENDPATH += $$PWD/../Prospec/debug
win32:CONFIG(release, debug|release): PRE_TARGETDEPS += $$PWD/../Prospec/release/libProspec.a
else:win32:CONFIG(debug, debug|release): PRE_TARGETDEPS += $$PWD/../Prospec/debug/libProspec.a
# Boost
INCLUDEPATH += C:/boost/boost_1_55_0/
LIBS += "-LC:/boost/boost_1_55_0/stage/lib/"
EDIT: the undefined reference errors happen only where I invoke functionality in a source file. For instance, if I construct a library object I get the error, but if I move that objects constructor into a header file, then compile is OK. Right now I'm not sure if the problem is due to the Qt environment, or me not understanding shared libraries in general.
The error you describe points to a linker error. It happens when a necessary object/lib file is not specified. The most likely scenario is this: you include a header and use a function from that header, but don't specify in which library that function is defined.
Small example:
//test.c
#include <winsock.h>
int main() { gethostbyname("localhost"); }
'undefined reference' linker error:
>gcc test.c
cczICEqq.o:test.c:(.text+0x1e): undefined refer ence to `gethostbyname#4'
collect2.exe: error: ld returned 1 exit status
In this case you would have to specify libwsock32.a like this:
gcc test.c -lwsock32
Also, note that a libsomething.a is not the only place where a reference can be resolved. You might have missed an object file.
Unfortunately without more details I am not able to tell you the exact problem.
You probably forgot to export your symbols, as described here on MSDN and in various questions on this website. It's a pain in general, and there are a few ways to handle this, none much better than the other.
This makes it so that the DLL and import library actually contain a reference to the symbols you compiled into it. You can compare it partially to GCC's symbol visibility, although that only works in Linux, and GCC also supports the stuff described on MSDN for Windows.
Had the same problem just now. Build was working fine on macOS/OSX but not on Windows with the same codebase. Thanks to rubenvb, who pointed me in the right direction. Here the full solution, how to do it for Qt:
Use Q_DECL_EXPORT on functions when building the lib. And use Q_DECL_IMPORT when using the functions from the lib.
Example how to do this here: https://wiki.qt.io/How_to_create_a_library_with_Qt_and_use_it_in_an_application#Creating_a_shared_library
Solved the problem in my case, hope it helps!
I'm trying to compile a GUI program based on the wxWidgets libraries. I get a lot of undefined references to "something". I tried to add a few libraries manually on the LIBS variable of QMake without success. How can i add all the wxWidgets libraries to QMake without hard coding each library? Below is my .pro file.
# simple.pro
TARGET = sample
HEADERS += main.h simple.h
SOURCES += main.cpp simple.cpp
LIBS += -LC:/SourceCode/Libraries/wxWidgets2.8/lib/gcc_dll/wxmsw28_core_gcc.dll \
-LC:/SourceCode/Libraries/wxWidgets2.8/lib/gcc_dll/wxmsw28_gcc.dll \
-LC:/SourceCode/Libraries/wxWidgets2.8/lib/gcc_dll/wxmsw28_aui_gcc.dll
INCLUDEPATH += C:/SourceCode/Libraries/wxWidgets2.8/include
CONFIG += release
The errors are of the form:
release/simple.o:simple.cpp:(.rdata$_ZTV6Simple[vtable for
Simple]+0x320): undefined reference to
`wxFrameBase::SetStatusBar(wxStatusBar*)'
First, you need to use the .a files to add to the linker.
Then you need to define WXUSINGDLL if you link against the shared libraries.
Additionally, you forgot
wxbase29u.a
Hope that helps.