Re: Patch to fix i960 objc runtime build

[Jim Wilson <wilson at cygnus dot com>]

>> + #define REAL_TYPE       _C_DBL
>
>OK, I give up.  How is this supposed to work?  REAL_TYPE as used in
>ROUND_TYPE_ALIGN is unrelated to the ObjC encoding char _C_DBL, at
>least as I understand the code.

The entire file is a hack.  It looks like objc has some kind of way to
create new types at run-time.  That requires a way to layout types at
runtime.  This was implemented by copying most of layout_type from
stor-layout.c into the objc runtime file encoding.c.  This includes various
macros that rely on gcc internals, such as ROUND_TYPE_ALIGN.  To make that
work, the file tries to map tree.h macros into the objc runtime equivalents.
The i960 port is failing here because it uses a bit of tree.h that isn't
already mapped to some objc runtime equivalent.

The whole approach looks risky to me.  A builtin function that calls into
the real layout_type function is probably a better solution.

Or maybe generalize the macros for type layout, so that it is easier
for libraries or other compilers to get the same type layout as gcc.

Jim