Re: gdb can't handle a DIE with both sibling and children

H. J. Lu
2003-07-31T19:56:42Z

On Thu, Jul 31, 2003 at 12:36:15PM -0700, David Carlton wrote:
> On Thu, 31 Jul 2003 14:20:49 -0400, Daniel Jacobowitz <drow@mvista.com> said:
>
> > It seems quite clear that the code above is deliberately only
> > visiting children of DW_TAG_enumeration_type and DW_TAG_namespace,
> > since those are the only things whose children it needs to visit. I
> > don't know why it was written that way, which does seem strange; I
> > imagine it does a lot of useless recursing.
>
> It's not written in the clearest fashion. I have this cleaned up on
> my branch to some extent, in a matter which, I hope, makes it clearer
> that, normally, we always want to skip children (whether or not the
> DIE happens to have a DW_AT_sibling attached to it): after all, most
> of the information contained in children is information that we don't
> need until a full symtab has been loaded. My rewrite then forks off
> the special cases for which we actually do want to look at children
> into their own special functions; maybe H.J. could add one for
> subprograms that looks for entry point tags. (Assuming, of course,
> that it really is important for the partial symbol table to know about
> entry point tags, not just the full symbol table.)
>

I don't know for sure how DW_TAG_entry_point works. It seems to me
that DW_TAG_entry_point should inherit DW_AT_accessibility and
DW_AT_high_pc from its parent.

H.J.
----
<1><8e>: Abbrev Number: 4 (DW_TAG_subprogram)
DW_AT_decl_line : 6
DW_AT_decl_column : 0
DW_AT_decl_file : 1
DW_AT_sibling : <125>
DW_AT_accessibility: 1 (public)
DW_AT_name : wkinit
DW_AT_type : <61>
DW_AT_prototyped : 0
DW_AT_high_pc : 0x8049456 134517846
DW_AT_low_pc : 0x8049206 134517254
DW_AT_external : 1
<2><c3>: Abbrev Number: 6 (DW_TAG_entry_point)
DW_AT_decl_line : 20
DW_AT_decl_column : 0
DW_AT_decl_file : 1
DW_AT_sibling : <f2>
DW_AT_name : wkprnt
DW_AT_type : <61>
DW_AT_low_pc : 0x80492ac 134517420
---
implicit none
call wkinit(10)
call wkprnt(5)
end

subroutine wkinit(wksize)
implicit none
integer wksize, nsize
integer jpr
integer jprint
save jpr

jpr = wksize

print *, 'On entry, wksize = ',wksize

nsize = wksize
return

entry wkprnt(jprint)
print *, 'On entry, jpr = ',jpr
print *, 'On entry, jprint = ',jprint
if (jprint.eq.2) then
jpr = 1-jpr
else
jpr = jprint
endif
print *, 'jpr = ',jpr
return

end