Bootstrap of trunk fails with Ada on powerpc-unknown-linux-gnu.

[Richard Kenner]

    I asked RTH about this before posting this here and he said Ada 
    front-end was broken and you need to create a temporary variable for the 
    ADDR_EXPR.

Well, it never did it before.  So what changed?

Also, we've informally defined GENERIC as "the tree language used before
the tree-ssa project" and ADDR_EXPR of a CONSTRUCTOR was most certainly
valid then.  So I don't see any justification for the restriction.

    I think there was another case like this in the Objective-C front-end
    which fixed to create a CONST_DECL for it.

It's not clear to me that a CONST_DECL is the most appropriate representation.
But it would seem that the gimplifier is what's best-suited to make that
determination.