ada frontend stuff lives in subdirectory - why?

[Maxim Blinov <maxim.a.blinov@xxxxxxxxx>]

Hi all, I was perusing through some frontend stuff, and found a curiosity.

$ find . | grep -E "config\-lang\.in"
./c/config-lang.in
./fortran/config-lang.in
./lto/config-lang.in
./d/config-lang.in
./cp/config-lang.in
./ada/config-lang.in
./ada/gcc-interface/config-lang.in
./objcp/config-lang.in
./go/config-lang.in
./jit/config-lang.in
./objc/config-lang.in
./brig/config-lang.in

How come ada puts an additional `config-lang.in` in the gcc-interface directory?

Maxim