I am distributing my source code via GitHub and GPL. I think that so long as I do that, it doesn't matter whether or not I use static linking in so far as licensing is concerned. My code is open-source, at least that's my intent.
I did find that I was able to easily modify the makefile emitted by Qt Creator to force static linking of most, but not all of the Linux system dependencies. Apparently, some of the OS libraries were available only as shared libraries and in some cases Qt libraries called shared Linux OS libraries so that I was not able to use all the available static libraries offered by Linux.
Too bad that it doesn't appear that one can roll up a desktop app all into one executable with no shared library calls. I'm thinking this would be nice since then, it could be distributed to any Linux machine without consideration of the distribution or kernel version?
Not sure, but probably you have to do a "nmake distclean" in between or it finds your license information. However, this is the opensource forum. You would need to approach the commercial, they have to able to give the proper answer.
I'm no expert but as far as i know, there is static and static. First static is static Qt-Libs second static is a real static standalone executable file.
If you want a real standalone executable you have to get a static version of all dependencies ".a" files not ".so". And you have to add some magic to the compiler -static -static-libgcc -static-libstdc++ (add in the Qt source to qtbase/mkspecs/linux-g++/qmake.conf) and if you want to use any kind of networking, you may also need static nss https://github.com/nss-dev/nss (some Linux versions still got static nss avaliable over packed managers).
And even if you don't use networking in your app, some other libs may include networking even if you don't use it in your code directly.