Not able to do reproducible builds

[streaksu]

I am trying to do reproducible builds of gprbuild projects, for testing that the builds are reproducible, I have used reprotest and disorderfs, which randomize OS reported folder content order.

By using those tools, I found out gprbuild seems to rely on the OS'es reported folder contents for linking order, instead of sorting the files itself, leading to discrepancies and non-reproducible builds if the order of said contents varies.

Is there a way to override this behaviour, or to sort them for the linker step? Am I wrong about this?

The gpr project file I am using to test this can be found here.