Problems referencing libraries on W7

towtruck

Hello All

I could use some help getting my App to reference a library. Thanks in advance:

First:
OS: W7, 64bit
Qt 5.5 for VS 2013 w/Creator 3.4.2
Visual Studio 2013

I created a library with VS2013 followig the pattern outlined here:
https://msdn.microsoft.com/en-us/library/ms235627(v=vs.120).aspx

Following Qt documetntation (http://doc.qt.io/qt-5/third-party-libraries.html), I added the following line to my *.pro file
LIBS += -L"C:\Users\xxxxxxxx\Documents\CASES_PC\CPP\lib\static" -lVS_casesIO
(the actual library name is VS_casesIO.lib)

I ran Qmake. There were no errors or warning from this process that I could see.

When I tried to run I got:
prjpath.obj:-1: error: LNK2001: unresolved external symbol "public: __cdecl PrjFilePath::PrjFilePath(char const *)" (??0PrjFilePath@@QEAA@PEBD@Z)

What am I doing wrong? Thanks to all.

kshegunov

@towtruck
You need to add your static library to PRE_TARGETDEPS.

towtruck

I added

PRE_TARGETDEPS += "C:\Users\xxxxxxxx\Documents\CASES_PC\CPP\lib\static\VS_casesIO.lib"

to my project file and go the same results... (yes, I reran qmake)

SGaist

Hi,

Maybe a silly question but, are you sure that the library and Qt are build for the same architecture ? 32 vs 64 bit.

towtruck

@SGaist
Never really thought about it, but since I am using Qt for VS2015, and I used VS2015 to build the library, all on the same machine, I kinda figured it was all consistent. How do I check?

SGaist

Something's not clear here, in your first post you wrote that you where using Visual Studio 2013, did you change in between ?

You can check the architecture in your project's settings or using a tool like Dependency Walker.

towtruck

My bad Vs2013 it is .
also,
It looks like the Qt build is 64 bit (From Projects | Build directory):
C:\Users\xxxxxxxx\Documents\build-cng12-Desktop_Qt_5_5_0_MSVC2013_64bit-Debug

SGaist

Indeed it is. Therefore is VS_casesIO.lib also 64bit ?

towtruck

@SGaist I sure expect so, but can;t figure out at the moment. Still a bit new to VS2013 as well...

SGaist

Then get Dependency Walker, it will be faster. When the library is loaded there's a 64 icon if it's a 64 bit build.