QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem

kshegunov

@ad5xj said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

While you may be correct about removing the CONFIG lines, It makes no difference in the current problem.

You should remove it nonetheless.

@ad5xj said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

The LIBS line you mention was removed from the .pro in an effort to find the problem posted. It too make no difference in finding the problem.

If you remove the LIBS line there is no sane way you'd be getting the same error. There's something very fishy here.

Could you also attach the generated Makefile.Debug? I don't see anything obviously wrong from the build log. Additionally, please check, if you have any files like .qmake.conf in your project directory?

VRonin

@ad5xj said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

The LIBS line you mention was removed from the .pro in an effort to find the problem posted. It too make no difference in finding the problem.

This is strange!
How do you recompile the project? Are you sure you are re-running qmake? Qt Creator is very bad at detecting changes in the .pro file so if you just click on "Build" it won't "process" your pro file from scratch but use a cached version of it (I'm oversimplifying but it's not the point here)

also notice that the .dll part should not be included in the LIBS line.Your original post showed it.

ad5xj

I shall post the Makefile.Debug for you.

I seems strange because it is out of the ordinary. I posted here because I have done all the normal troubleshooting. I cleaned the project. Removed the Makefile. removed the compile generated folders (.obj, .moc, .ui, etc) and started over.

I have run the compile with and without the .dll. With and without the user LIBS line. It makes no difference.

As mentioned before this is a running project on Linux Mint 18. This is a problem unique to Microsoft Windows 10 Qt 5.7.0 32-bit MinGW. All the suggestions so far would affect the RUNNING application - NOT the problem posted. While I appreciate the suggestions, I would like to stay on topic.

BTW I have done a text search in the Makefiles for any reference to c:\utils and there is none. The only support or configure file I have found that does is the one mentioned before in the Qt install folder under mkspecs files. It is not something I can change with the QtCreator options.

I am still trying to figure out how to attach a file in this forum since the new format. I don't see it. Maybe someone can help there.

kshegunov

@ad5xj said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

I shall post the Makefile.Debug for you.

Use an external site and just post the link here. We don't have file/image uploads in the forum.

This is a problem unique to Microsoft Windows 10 Qt 5.7.0 32-bit MinGW.

Or to your mint development setup being too lenient or both.

All the suggestions so far would affect the RUNNING application - NOT the problem posted.

Nope, all the suggestions so far were definitely referring to the BUILD error you're getting.

While I appreciate the suggestions, I would like to stay on topic.

No one has strayed so far.

ad5xj

Well I have some progress albeit minor overall. I am able to compile all but the linker is not seeing the references to the .dll in the application. I will note that both QWT and FFTW3 folders are in the project path.

Here is the current .pro:

TARGET = ardoptnc
TEMPLATE = app
target.path = bin

QT     += widgets multimedia serialport
CONFIG += qt thread c++11 #silent

MOC_DIR = .moc
OBJECTS_DIR = .obj
UI_DIR  = .ui

INCLUDEPATH += \
    $$FFTW3_INCL_PATH \
    $$QWT_INCL_PATH

INCLUDEPATH += \
    .ui \
    inc \
    inc/fft \
    inc/network \
    inc/ui \
    inc/utils \
    inc/sound \
    inc/widgets \
    inc/protocol

DEPENDPATH += \
    $$FFTW_LIB_PATH \
    $$QWT_LIB_PATH

HEADERS += $${FFTW3_LIB_PATH}/fftw3.h

HEADERS += \
    inc/widgets/vumeterwidget.hpp \
    inc/widgets/waterfallwidget.hpp

HEADERS += inc/globals.hpp

HEADERS += \
    $${QWT_INCL_PATH}/qwt.h \
    $${QWT_INCL_PATH}/qwt_plot_spectrogram.h \
    $${QWT_INCL_PATH}/qwt_scale_map.h

HEADERS += \
    inc/network/sslparams.h \
    inc/network/tcpipserver.hpp

HEADERS +=  inc/sound/audioio.hpp

HEADERS += inc/utils/utils.hpp

HEADERS += inc/fft/fftcalc.hpp

HEADERS += \
    inc/tncsetup.hpp \
    inc/radiosetup.hpp \
    inc/tncpanel.hpp

SOURCES += \
    network/sslparams.cpp \
    network/tcpipserver.cpp

SOURCES += sound/audioio.cpp

SOURCES += fft/fftcalc.cpp

SOURCES += utils/utils.cpp

SOURCES += \
    widgets/vumeterwidget.cpp \
    widgets/waterfallwidget.cpp

SOURCES += \
    tncsetup.cpp \
    radiosetup.cpp \
    tncpanel.cpp \
    main.cpp

FORMS   += \
    ui/tncsetup.ui \
    ui/radiosetup.ui \
    ui/tncpanel.ui

LIBS += -L$${QWT_LIB_PATH}/ -lqwt
LIBS += -L$${FFTW3_LIB_PATH}/libfftw3-3.dll
LIBS += -L$${FFTW3_LIB_PATH}/libfftw3l-3.dll
LIBS += -L$${FFTW3_LIB_PATH}/libfftw3f-3.dll

I get this error when linking (abbr for clarity):

./.obj\fftcalc.o: In function `ZN7fftCalcD2Ev':
C:\Projects\C++\ardoptnc/fft/fftcalc.cpp:15: undefined reference to `_imp__fftw_destroy_plan'
C:\Projects\C++\ardoptnc/fft/fftcalc.cpp:16: undefined reference to `_imp__fftw_free'
C:\Projects\C++\ardoptnc/fft/fftcalc.cpp:17: undefined reference to `_imp__fftw_free'
./.obj\fftcalc.o: In function `ZN7fftCalc5doFFTEv':
C:\Projects\C++\ardoptnc/fft/fftcalc.cpp:49: undefined reference to `_imp__fftw_execute'
./.obj\fftcalc.o: In function `ZN7fftCalc4initEiii':
C:\Projects\C++\ardoptnc/fft/fftcalc.cpp:64: undefined reference to `_imp__fftw_destroy_plan'
C:\Projects\C++\ardoptnc/fft/fftcalc.cpp:65: undefined reference to `_imp__fftw_free'
C:\Projects\C++\ardoptnc/fft/fftcalc.cpp:66: undefined reference to `_imp__fftw_free'
C:\Projects\C++\ardoptnc/fft/fftcalc.cpp:67: undefined reference to `_imp__fftw_malloc'
C:\Projects\C++\ardoptnc/fft/fftcalc.cpp:68: undefined reference to `_imp__fftw_malloc'
C:\Projects\C++\ardoptnc/fft/fftcalc.cpp:71: undefined reference to `_imp__fftw_plan_r2r_1d'
collect2.exe: error: ld returned 1 exit status

The lines referred to are just library calls to FFTW. The fftw3.h is specified in the includes. The LIBS does have the correct path and it is in the project path - yet the undefined referreces. Something is not right at all.

kshegunov

@ad5xj
Your linkage is incorrect, thus the fftw isn't linked, thus you get the errors.

LIBS += -L$${FFTW3_LIB_PATH}/libfftw3-3.dll
LIBS += -L$${FFTW3_LIB_PATH}/libfftw3l-3.dll
LIBS += -L$${FFTW3_LIB_PATH}/libfftw3f-3.dll

should be:

LIBS += -L$${FFTW3_LIB_PATH} -lfftw3-3 -lfftw3l-3 -lfftw3f-3

And you should have the appropriate .lib (or .a if you're using mingw) files in $${FFTW3_LIB_PATH}.

JKSH

@ad5xj said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

I get this error when linking (abbr for clarity)

Do you only get errors for FFTW, or Qwt as well?

LIBS += -L$${FFTW3_LIB_PATH} -lfftw3-3.dll

That's supposed to be -lfftw3-3 (no ".dll")

LIBS += -L$${FFTW3_LIB_PATH}/libfftw3-3.dll
LIBS += -L$${FFTW3_LIB_PATH}/libfftw3l-3.dll
LIBS += -L$${FFTW3_LIB_PATH}/libfftw3f-3.dll

FFTW3_LIB_PATH == "C:/FFTW3/", right? That means your lines expand to things like LIBS += -LC:/FFTW//libfftw3-3.dll (2 slashes).

Let's do a sanity check: Replace all the variables in your *.pro file with hard-coded paths, e.g. LIBS += -L"C:/FFTW3/" -lfftw3-3 -lfftw3l-3 -lfftw3f-3 and see what happens.

[EDIT: @kshegunov beat me to it!]

HEADERS += $${FFTW3_LIB_PATH}/fftw3.h

...

HEADERS += \
    $${QWT_INCL_PATH}/qwt.h \
    $${QWT_INCL_PATH}/qwt_plot_spectrogram.h \
    $${QWT_INCL_PATH}/qwt_scale_map.h

Do not add 3rd-party library headers to HEADER. Instead, add their folders to INCLUDEPATH.

By adding the files to HEADER, you are asking the toolchain to compile the headers into your binaries. This causes errors if the headers contain any definitions that have already been built into the 3rd party DLL. This also causes Qt's code generator (moc) to generate a new copy of the QObjects that are found in the headers, which breaks the signal-slot mechanism (among other things) for the library.

LIBS += -L$${QWT_LIB_PATH}/ -lqwt

This is not strictly necessary, but the cleanest way to use Qwt in your project is to write include(C:/QWT/Qwt-6.1.3/features/qwt.prf) in your *.pro file. You can then get rid of all the other Qwt-related lines.

ad5xj

Thanks for the QWT tip I will try that.

As to the fftw3 dlls ... I did have it the way you describe and the linker complains. With some experimentation, I did find the current syntax to work. It may not be as expected but it works. Go figure.

I have had little nor no problem with QWT. No error messages about the QWT .dlls at all.

SGaist

What exact error do you still have with Qwt ?

JKSH

@ad5xj said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

With some experimentation, I did find the current syntax to work. It may not be as expected but it works. Go figure.

When you say "it works", do you mean everything builds and links correctly? Or that the linker doesn't complain about missing libraries? There's a difference.

A typo in -l gets reported directly by your toolchain. Example:

LIBS += -L"C:/FFTW3/" -lfftw4-4

...

ld.exe: cannot find -lfftw4-4

In contrast, a typo in -L does not get detected or reported directly. Instead, you just get the generic "undefined reference" errors.

Anyway, note also that:

-L is for specifying a folder that the linker should search
- -LC:/FFTW3/libfftw3-3.dll makes your toolchain look inside a folder called "C:/FFTW3/libfftw3-3.dll/"... which probably doesn't exist (but the toolchain doesn't tell you that)
-l is for specifying a filename root
- -lFoo makes your toolchain link against a file called libFoo.dll (inside the folders specified by -L)

As to the fftw3 dlls ... I did have it the way you describe and the linker complains.

Please try again, especially with hard-coded paths. Then, post your unmodified .pro file and error messages.

ad5xj

Sorry for being ambiguous. I mean to say the linker finds the libraries and tries to link. Whereas before it could not find the libraries -lfftw3-3.dll or -lfftw3.

I understand your explanation to be the expected. I am only reporting the actual results of repeated attempts with failure before hitting on what works even if it is not what "should" be correct.

BTW SGiast I do not now, nor ever have had a problem with QWT libraries during the compile and link process. Sorry if I was not clear before.

JKSH

@ad5xj said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

Sorry for being ambiguous. I mean to say the linker finds the libraries and tries to link.

No worries. So, does that mean all problems are gone now?

ad5xj

Well I do not know how to answer you JKSH.

It seems the LIBS statement is not interpreting the path and .dll name correctly for FFTW3 dll's. As you pointed out earlier, if the correct syntax is used, the linker does not find the libraries. When specified as -L<path>/<libname.dll> the linker seems to find the libraries and tries to link with them. Not sure if that is a bug in the Windows 32 bit version of qmake or something else. It needs to work as advertised but doesn't.

I also notice that if a substitution like $$FFTW3_LIB_PATH is used but not defined, the qmake hangs indefinitely without giving a message. Something new I just discovered.

I will also say that in desperation, I have uninstalled Qt, cleaned the registry and file system, and reinstalled Qt with no change in the problem.

At this point I believe the LIBS problem is a bug and possibly the substitution problem as well.

JKSH

@ad5xj said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

When specified as -L<path>/<libname.dll> the linker seems to find the libraries and tries to link with them.

How do you know that the linker found the libraries? What messages do you get?

If you see "Undefined references", that means your linker couldn't find the libraries.

I also notice that if a substitution like $$FFTW3_LIB_PATH is used but not defined, the qmake hangs indefinitely without giving a message. Something new I just discovered.

Hmm... sounds like a bug, but I wouldn't worry about it for now.

At this point I believe the LIBS problem is a bug and possibly the substitution problem as well.

That's why I asked you to get rid of substitution and use hard-coded paths like LIBS += -LC:/FFTW3 -lfftw3-3

You can also try LIBS += C:/FFTW3/libfftw3-3.dll (don't write "-L")

Well I do not know how to answer you JKSH.

The answer is, "No, the problems are not yet gone" ;)

We'll get there eventually, I'm sure.

kshegunov

@ad5xj said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

It seems the LIBS statement is not interpreting the path and .dll name correctly for FFTW3 dll's.

What statement are you using? One doesn't link to .dll files, and one doesn't need a path to a .dll file for linkage.

When specified as -L<path>/<libname.dll> the linker seems to find the libraries and tries to link with them.

That most certainly isn't true. -L is for specifying only additional link directories.

It needs to work as advertised but doesn't.

How is it advertised?

ad5xj

JKSH

I created a much smaller sub-project with only one form (mainwindow) and tested to see what would happen with the two different LIBS statements.

When stated: LIBS += -L$${FFTW3_LIB_PATH}/ -llibfftw3-3.dll

The linker does not find the dll.

When stated: LIBS += -L$${FFTW3_LIB_PATH}/libfftw3-3.dll

The linker finds the dll and successfully links the exe. It does run as expected.

However, in the larger project, this approach does not work - it does have the undefined reference error messages for the FFTW3 functions with the latter form of the LIBS statement and does not find the dlls (link output - file not found) with the former.

kshegunov

Your message seems contradictory to the thread messages so far. I have tried to eliminate the LIBS statement referencing the dlls but that does not even work at all.

kshegunov

Contradictory? Redundant is more like it. Let me quote a couple:

@VRonin said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

also you never set the LIBS variable
LIBS += -L$${QWT_LIB_PATH} -L$${QWT_LIB_PATH} -lfftw3-3 -lqwt

@kshegunov said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

should be:

LIBS += -L$${FFTW3_LIB_PATH} -lfftw3-3 -lfftw3l-3 -lfftw3f-3

And then I added:

And you should have the appropriate .lib (or .a if you're using mingw) files in $${FFTW3_LIB_PATH}.

Here's the qmake variable reference, as you can see yourself there's no guesswork involved in all this.

JKSH

@ad5xj said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

However, in the larger project, this approach does not work

Did you set $${FFTW3_LIB_PATH} to different values in the 2 different projects?

C:/FFTW3/ is not equal to C:/FFTW3

When stated: LIBS += -L$${FFTW3_LIB_PATH}/ -llibfftw3-3.dll

The linker does not find the dll.

That should be -lfftw3-3, not -llibfftw3-3.dll

ad5xj

kshegunov

You must be confused. The thread has moved far past the VRonin post.

As to your reference to the qmake variable reference; here is the quote from the docs:

"LIBS
Specifies a list of libraries to be linked into the project. If you use the Unix -l (library) and -L (library path) flags, qmake handles the libraries correctly on Windows (that is, passes the full path of the library to the linker). The library must exist for qmake to find the directory where a -l lib is located.
For example:

unix:LIBS += -L/usr/local/lib -lmath
win32:LIBS += c:/mylibs/math.lib
"
You can plainly see the full pathname including the file name is in the LIBS statement. I understand the example is a static library reference and not a dll but there is no such distiinction made - with or without the .dll extension.

I did not feel that LIBS += $${FFTW3_LIB_PATH}/libfftw3-3.dll violated that example. It seems you have another idea and I would like to hear it. I am just looking for the correct way to get this done. The docs do not seem to contradict my use of the above statement, but I am open to a different way of doing it. Doing what you indicate does not work either.

I have -- several times at suggestions from other posts -- eliminated the dll reference from the .pro file. As stated this does not work.

Now, whether this is a bug or some quirk of qmake I do not know. I just want it to work.

JKSH

No. The same .pri was used to define the variables in the sub-project. So no there essentially no difference in the variable substitution value.

kshegunov

@ad5xj said in QtCreator 4.1.0 Qt 5.7.0 Windows 10 MinGW problem:

You must be confused.

I must have been.