I build my own static library with gcc and ar like this.
g++ \
... list of library sources ... \
... a lot of -L -l -I -D options etc... \
-c \
&& ar crf ./lib/libpackager.a *.o
Then I use this library in my app. Currently I built it like this.
g++ \
myApp.cpp \
... same -L -l -I options as in library ... \
-L. -lpackager \
-o myApp
It works, but I am little odd for me that I need to duplicate all -l and -L during building the app. Is it possible include all this library dependencies inside the library. My goal to build app like this.
g++ myApp.cpp -L. -lpackager -o myApp
Transferring comments into an answer.
Specifying the -l and -L operations when compiling to object files is irrelevant. Some versions of GCC warn about arguments that won't be used because they are link-time arguments, and linking won't be used when you include the -c flag.
The ar command doesn't know what to do with the C compiler's -l and -L arguments (it might have its own uses for the flags; one version of ar accepts but ignores -l).
So, you have to specify the dependencies when you link with the static library. That is the way life has been since the early 70s — that aspect hasn't changed yet. Shared libraries can be built with the dependency information, but not static libraries.
As I understand it, I need to build a shared library and link it in a static way, right?
No. You either need to build and link a shared library as a shared library, or you need to accept that using a static library means you will need to specify other libraries on the command line when you use this library. There are systems to help manage such information; pkg-config is one such. AFAIK, you cannot link a shared library in a 'static way'.