Re: [rfa] Deprecate msymbol.info, add msymbol.bfd_symbol?

[Andrew Cagney <ac131313@redhat.com>]

> ac says:
> 
> 	sym = lookup_minimal_symbol_by_pc (memaddr);
> 	if (sym && sym->bfd_symbol is "elf like")
> 	  return (ELF_ST_TYPE (((elf_symbol_type *) 
> (sym->bfd_symbol))->internal_elf_sym.st_info) == STT_LOPROC)
> 	else
> 	  return 0;
> 
> Okay, I see.  The existing code has a hook in the symbol reader that
> reads the bfd symbol and calls MSYMBOL_SET_SPECIAL to stash some bits in
> msymbol.info for later.  You would get rid of the hook or simplify and
> just store a simple pointer in msymbol.bfd_symbol.  Have I got that
> right?

Yep!

> Sounds like a great idea to me.  A bunch of squirrelly caching and
> casting code would go away.
> 
>                /* Pass symbol size field in via BFD.  FIXME!!!  */
>                size = ((elf_symbol_type *) sym)->internal_elf_sym.st_size;
>                msym = record_minimal_symbol_and_info
>                  ((char *) sym->name, symaddr,
>                   ms_type, (void *) size, sym->section, objfile);
> 
> Yeah, for this code, you could either have msymbol.size or use the
> information available from msymbol.bfd_symbol.  Anything but
> mysmbol.info.

Yep!

>> This could immediatly eliminate two of them.  I think the coff version 
>> of ARM could also be eliminated if coffread (yea, right ... :-) fully 
>> utilized BFD.
> 
> 
> I'm saying that this code is already dead:
> 
>                 gdb_assert (sizeof (void *) >= sizeof (cs->c_sclass));
>                 msym = prim_record_minimal_symbol_and_info
>                   (cs->c_name, tmpaddr, ms_type, (void *) (long) cs->c_sclass,
>                    sec, NULL, objfile);
> 
> I'm not sure about these lines immediately after it:
> 
>                if (msym)
>                   COFF_MAKE_MSYMBOL_SPECIAL (cs->c_sclass, msym);
> 
> I think you are saying that coffread.c can be made to work using
> the new fields.  I don't know whether the existing code works or not,
> I'm juse pointing to the deadness.

Yep!

(COFF_MAKE_MSYMBOL_SPECIAL is currently be used by arm.  coffread 
doesn't use bfd_canonicalize_symtab so doesn't have access to the bfd 
symbol.)

Andrew