11.8.1 Building aggregate library projects

For example, we can define an aggregate project Agg that groups A, B and C:

        aggregate library project Agg is
           for Project_Files use ("a.gpr", "b.gpr", "c.gpr");
           for Library_Name use ("agg");
           for Library_Dir use ("lagg");
        end Agg;

Then, when you build with:

         gprbuild agg.gpr

This will build all units from projects A, B and C and will create a static library named libagg.a into the lagg directory. An aggregate library project has the same set of restriction as a standard library project.

Note that a shared aggregate library project cannot aggregates a static library project. In platforms where a compiler option is required to create relocatable object files, a Builder package in the aggregate library project may be used:

        aggregate library project Agg is
           for Project_Files use ("a.gpr", "b.gpr", "c.gpr");
           for Library_Name use ("agg");
           for Library_Dir use ("lagg");
           for Library_Kind use "relocatable";
     
           package Builder is
              for Global_Compilation_Switches ("Ada") use ("-fPIC");
           end Builder;
        end Agg;

With the above aggregate library Builder package, the -fPIC option will be passed to the compiler when building any source code from projects a.gpr, b.gpr and c.gpr.