Hello, I am building "boost" libraries from boost source code and I have two options: to build it "static" or to build it "shared" (e.g. dynamic). Which is better idea?
I prefer dynamic (shared) linking but when I tried to build boost shared libraries (on Ubuntu Linux), I got lots of errors or warnings (why there are always errors, warning, notes and other stuff when compiling, grrrrrrrr), so I don't know if it was compiled alright?
Thanks.
Better is subjective. Shared cuts down on size, at the risk of dependencies. Static solves dependency issues but increases the size.
For your purposes, I'd say building it in which ever way gets you to code faster is the better solution.
Static libraries are used when you don't need to dynamically load a componenet into the program. It is compiled into the exe.
A shared library is loaded on runtime, and is usually used for plugins or extentions.
Imo a static library is better here since you will probably load the boost shared library anyway on the program's startup.
Why do you prefer a shared library?
You will almost always want to use shared libraries over static libraries. A key advantage to using shared libraries is that if the library is updated, you can replace the shared libraries with the newer version (assuming binary compatibility) and reap the benefits of the improved implementation without recompiling your application. Additionally, using shared libraries saves space, if multiple programs are using them.
As for the dependencies issue, it is possible to link against a specific version of a shared library, or to place your shared libraries in a special location that is specific to your program -- which doesn't save you space, but which does give you the flexibility associated with shared libraries -- so that should not be a reason to choose static libraries over shared libraries. I am actually hard pressed to come up with a single instance, on a typical desktop, laptop, or server machine where using static libraries is better than using shared libraries.
P.S. If you are trying to install Boost on Ubuntu Linux, just run "sudo apt-get install libboost1.37-dev". You were probably getting errors because you did not install all of Boost's dependencies. These are automatically downloaded and installed when you use Ubuntu's apt-get package manager to install it. Also, it is generally better to use an OSs package manager for installing software packages, than to build from source. For example, using the package system's version of Boost will make it more likely that your software will run smoothly on other Ubuntu Linux deployments which use the package manager's version of Boost.
P.P.S. Boost uses some very advanced features of C++. It kind of pushes C++ to the limit. It is not uncommon to see warnings when compiling Boost. In fact, I have built Boost quite a number of times on various operating systems, and I don't recall a time when there were no warnings.
The recommended way to use the Boost C++ libraries on Linux is via shared linking. On an Ubuntu Linux box already configured for development you should not get any errors at all. Compilation warnings are expected -- for various mindset, technical, and time-constraint issues there are a few produced. Since regular release testing covers Ubuntu, I would not worry about functionality of created libraries -- if there's .so, it should work.