ar command fails silently

[himamis]

Related to issue #572
With a project over 3500 files, the createStaticLibrary command fails silently. The failing command is ar used to link the object files, creating a static library.
I've extraced the command, and ran in, I get the Argument list too long error.

If I move the files into Xcode, and compile it there, it is successful. That is, because Xcode uses libtool instead of ar, with the parameter -objectlist file, where file contains the names of the objects to link together (http://www.gnu.org/software/libtool/manual/libtool.html#Link-mode). In essence, libtool can act as a wrapper for the ar library. This is the same solution that we implemented in #572.

My proposal here, is to remove the linking tasks from the native compilation, and use libtool instead, with the same arguments, and using an arg file.

@brunobowden we might want to wait with the new release, until we can find a solution to this problem.

[himamis]

Discussion about the same problem:
https://discuss.gradle.org/t/how-to-work-around-argument-list-too-long-error-when-compiling-library-c-plugin/5000.