* d10v-tdep.c (d10v_frame_chain_valid): Remove unnecessary tests.
* hppa-tdep.c (hppa_frame_chain_valid): Remove unnecessary test.
* blockframe.c: Include "gdbcmd.h" and "command.h".
(backtrace_below_main): New variable.
(file_frame_chain_valid, func_frame_chain_valid)
(nonnull_frame_chain_valid, generic_file_frame_chain_valid)
(generic_func_frame_chain_valid): Remove functions.
(frame_chain_valid, do_flush_frames_sfunc): New functions.
(_initialize_blockframe): New function.
* Makefile.in (blockframe.o): Update dependencies.
* frame.c (frame_saved_regs_id_unwind, get_prev_frame): Remove FIXME
comment. Call frame_chain_valid ().
* frame.h: Remove old prototypes. Add prototype for
frame_chain_valid and update comments to match.
* gdbarch.sh: Change FRAME_CHAIN_VALID into a predicated function.
Remove old comment.
* gdbarch.h: Regenerated.
* gdbarch.c: Regenerated.
Plus updates to all other targets not to provide a FRAME_CHAIN_VALID.
symbol special handling when INHIBIT_SUNSOLIB_TRANSFER_TABLE_HACK
is defined.
* infrun.c (IN_SOLIB_CALL_TRAMPOLINE): Renamed from
IN_SOLIB_TRAMPOLINE. All callers changed.
(IN_SOLIB_RETURN_TRAMPOLINE): Provide default definition.
(wait_for_inferior): Handle single stepping through trampolines on
return paths from shared libraries.
* config/pa/tm-hppa.h (IN_SOLIB_CALL_TRAMPOLINE): Use
in_solib_call_trampoline.
(IN_SOLIB_RETURN_TRAMPOLINE): Use in_solib_return_trampoline.
(INHIBIT_SUNSOLIB_TRANSFER_TABLE_HACK): Define.
* hppa-tdep.c (in_solib_call_trampoline): New function.
(in_solib_return_trampoline): New function.
* dst.h, dstread.c, config/m68k/{apollo68b.mt,tm-apollo68b.h}:
New files.
* config/m68k/nm-apollo68b.h: Add more defines.
* configure.in: Recognize apollo target, not just host.
