How to link with Boost libraries in Qt Creator?

franc

Hi all, I need to build a project using Qt Creator. This project needs to link with the static libraries boost_system and boost_thread.

I have compiled Boost libraries using Visual Studio 2015 (v.14.0), so that I have included the following lines to my .pro file:

DEFINES = BOOST_ALL_NO_LIB
Boost_USE_STATIC_LIBS = ON
win32 {
    DEFINES = BOOST_ALL_NO_LIB
    BOOSTHOME = C:/Boost
    INCLUDEPATH += C:/Boost/include/boost-1_55
    DEPENDPATH += C:/Boost/include/boost-1_55
    LIBS += -LC:/Boost/lib \
            -lboost_system-vc140-mt-gd-1_55 \
            -lboost_thread-vc140-mt-gd-1_55
     !win32-g++: PRE_TARGETDEPS += C:/Boost/lib/boost_system-vc140-gd-1_55.lib
     !win32-g++: PRE_TARGETDEPS += C:/Boost/lib/boost_thread-vc140-mt-gd-1_55.lib
}

The variable BOOST_ALL_NO_LIB should tell the system not to select automatically the linking libraries, which are explicitly expressed in the LIBS variable.

During the linking phase, the following error occurs:

error: LNK1104: cannot open file 'libboost_system-vc120-mt-gd-1_55.lib'

which is very strange, since I have never installed Visual Studio 12.0 on this PC, and it should link with boost_system-vc140. I tried every suggestion found on other forums, like modifying auto_link.hpp, including auto_link.hpp in the code to link manually (and rebuild many times Boost libraries in the middle), but the system always tries to link with boost_system-vc120, and not boost_system-vc140.

I write because at this point I am not totally sure whether I am using the .pro file in a proper way, and I do not know whether it follows what I state (define BOOST_ALL_NO_LIB, expressing LIBS, etc...).

Any idea? Is it possible to show the environmental variables during the linking phase with Qt Creator?

SGaist

Hi,

Did you check the content of the Makefile generated ?

One thing that doesn't look correct is your DEFINES =, this nukes all values that might have been set before.
What does Boost_USE_STATIC_LIBS do ? Is it also a define ?

franc

Boost_USE_STATIC_LIBS when it is set on ON, should tell the linker to use the static version of the boost libraries.
I have solved the issue: the problem was an incompatibility between architectures. I had to rebuilt boost libraries in X86 architecture instead of x64.

Then, I have changed the line:

LIBS += -LC:/Boost/lib \

with:

LIBS += -LC:\Program Files\boost_1_55_0\stage\x86\lib \

but now I have another linker problem:

LINK : fatal error LNK1104: cannot open file 'Files\boost_1_55_0\stage\x86\lib.obj'

I think that the white space between "Program" and "Files" is causing some issues. I am trying to solve the problem, but if someone has already a solution it is well accepted!

EDIT: I changed again the above line with:

LIBS += -L"C:\Program Files\boost_1_55_0\stage\x86\lib" \

It builds, but the program does not even start. The debugger returns the error message:

The CBD process terminated.

because the boost_thread-vc140-mt-gd-1_55.dll and boost_system-vc140-mt-gd-1_55 libraries cannot be found. It is very strange because I want to use static library. And, anyway, the problem should not be present because in C:\Program Files\boost_1_55_0\stage\x86\lib I do have both libraries (both .dll and .lib).

EDIT: the problem has been solved rebooting the machine. I have never switched off my computer after having built the Boost libraries with x86 architecture. Windows is awesome.

SGaist

In the Run part of the Project panel, modify the PATH environment variable and add C:\Program Files\boost_1_55_0\stage\x86\lib to it.

aha_1980

@SGaist FYI: Creator does this automatically if you specify LIBS+=-L<path>.