Re: [rfa] lookup_symbol_aux_minsym

[Jim Blandy <jimb at redhat dot com>]

Elena Zannoni <ezannoni@redhat.com> writes:
> David Carlton writes:
>  > Here's the part of my previous lookup_symbol_aux patch where I combine
>  > the two versions of the minsym code into a single function
>  > lookup_symbol_aux_minsym.  I've tried to mimic the current flow of
>  > control as exactly as possible: in particular, this code is run at a
>  > different time in HPUXHPPA situations than in other situations, and I
>  > preserved the weird circumstances in which the minsym check might lead
>  > to a NULL return.  (I'm not sure either of those is a good idea, but
>  > that's a matter for a separate patch.)
>  > 
>  > Here are the differences between the two versions of the minsym code
>  > in the current version of lookup_symbol_aux.
>  > 
>  > * The comments differ, to some extent: I picked whichever version of
>  >   the comment I liked more.
>  > 
>  > * The non-HP code has
>  > 
>  >     s = find_pc_sect_symtab (SYMBOL_VALUE_ADDRESS (msymbol),
>  > 			     SYMBOL_BFD_SECTION (msymbol));
>  > 
>  >   where the HP code has
>  > 
>  >     s = find_pc_symtab (SYMBOL_VALUE_ADDRESS (msymbol));
>  > 
>  >   Both seem fine to me; I picked the former, but I don't have a strong
>  >   feeling about this.
>  > 
> 
> Some random comments....
> 
> 
> I don't know about this. find_pc_symtab calls find_pc_sect_symtab with
> NULL as section parameter, unless there are overlays involved.  I
> don't know if it would make a difference, but it seems that it would
> in case of overlays, because finding the section is a bit more involved.
> Maybe we should adopt the other approach? I.e. use the 
> 
> s = find_pc_symtab (SYMBOL_VALUE_ADDRESS (msymbol));
> 
> What do you think?

Actually, I'm pretty sure we're supposed to use find_pc_sect_symtab.
The non-'sect' version is just for cases where we don't know the
section associated with the address --- when we do know the section,
we should provide it, so find_pc_sect_symtab can do clever
overlay-related things.  Since we're starting with a linker symbol, we
definitely know the section, and we should pass that along.