When I cross compile from Linux/i686 to Linux/ia64 with --enable-languages=c,c++, Ada compiler is enabled. The problem is BOOT_LANGUAGES = c ada in gcc/Makefile. Apparently, it was overriden for native build, but not for cross build.
Wrong target is used for cross compiler build.
Reopening.
*** Bug 29531 has been marked as a duplicate of this bug. ***
Confirmed.
As mentioned this was invalid because HJL used the wrong make target.