[Solved] Linking in a static library

franku

Hi Andre, open the libWidgets.a with a texteditor. If it is an import lib for a dll, then the dll name will be listet in it, otherwise not.

Second use the -static command-line option to force "static linking ":http://pages.cs.wisc.edu/~thomas/X/static-linking.html of the lib. I remember dynamic linking is the default.

franku

Other ideas, for the link-section try to use this:

@
CONFIG( Debug ) {
LIBS += -shared -L../Libraries/Widgets/debug -lWidgets
PRE_TARGETDEPS += ../Libraries/Widgets/debug/libWidgets.a
} else {
@

andre

Hmmm... weird. It does contain Widgets_dll in several places. Does that mean it was build wrong?

Adding -static to the LIBS variable did not help. Or did I misunderstand your second solution?

andre

[quote author="franku" date="1345213035"]Other ideas, for the link-section try to use this:

@
CONFIG( Debug ) {
LIBS += -shared -L../Libraries/Widgets/debug -lWidgets
PRE_TARGETDEPS += ../Libraries/Widgets/debug/libWidgets.a
} else {
@[/quote]

I don't understand this. I don't want a shared library, but a static one.

franku

Ok. If the libwidgets.a lib was built as static lib, then it should not contain references to any dll (I looked for it in some static lib i have for sure and there wasn't). If the -static solution does not static link then in my opinion the build of libwidgets.a went wrong. I do not know yet where or when static and dll libs are used in common.

However, the order of -static and -lwidgets is important. You may have read in the linked comment above. But in my opinion, maybe I am false, the lib is built wrong.

franku

Sorry, this was a typo. I ment -static

andre

Thank you for your help so far.

I think so you are right something goes wrong in the build, but I for the life of me can't figure out what it might me. I have pasted my "build output":http://pastebin.com/cmxjEV42 online. While inspecting the contents of the CONFIG variable, I did find a "shared" there. The documentation lists "dll" as the keyword that triggers building a shared library, but I tried removing it explicitly anyway. That did not help.

I had already tried putting the -static in the LIBS (before the lib itself), without result.

Other suggestions are welcome.

franku

Ok, I will have a look in the build process. Maybe I find out what happens.
rgds, .. frank

franku

Do you have the output for your application being lonked, too?

Uups, linked. With icecream in one hand.

andre

Sorry for the absense.

I managed to link properly! I noticed from the output that the ar tool was used, and that gave me a good feeling. I deleted the Makefiles and all object files from the libary, and the makefiles and produced binary from the application itself. I then build the library again, and no more .dll strings appeared in the result. Then, I build and linked the application, and it just worked.

It seems that, even after cleaning, manually running qmake and doing a complete rebuild, I still had some stale stuff that messed up my build.

Thanks for your help!

franku

Glad having helped to [solve]
:-)

kumararajas

Hi Andre,

I am facing the similar problem.

I am unable to link my static library to my application.

My application is unable to see the functions inside the library.

I get 'undefined reference to' when I access the function.

Any thoughts on this?

Thanks,
Kumar