gimplify_parameters

[Richard Kenner]

    The following fixes the ICE on s-fileio.adb.  I guess I'll run it through
    and see what happens.  And then try and fix the C problems you uncovered.

	* gimplify.c (eval_save_expr): New.
	(gimplify_one_sizepos): Use it.

My gut feeling was right.  It didn't get very far into the Ada RTS build,
blowing up compiling g-debpoo.adb with an SSA_NAME in an array bound when
writing debugging information.

You really *can't* call gimplify_type_sizes just because a type used
as a the type of parameter.  This stuff is very tricky, but I can
assure you it won't work if you do that.  The only solution I see is
somehow to arrange to call it only in the specific case in question,
which is unique to C.

I also don't think it's good enough to only gimplify a SAVE_EXPR.