[PATCH] D27040: [ELF] - Add support for access to most of synthetic sections from linkerscript.

[Rui Ueyama via llvm-commits]

ruiu added inline comments.


================
Comment at: ELF/SyntheticSections.cpp:1589-1590
+template <class ELFT> bool VersionTableSection<ELFT>::empty() const {
+  bool HasVerNeed = In<ELFT>::VerNeed->getNeedNum() != 0;
+  return !In<ELFT>::VerDef && !HasVerNeed;
+}
----------------
grimar wrote:
> ruiu wrote:
> > grimar wrote:
> > > ruiu wrote:
> > > > I don't understand these conditions. Is this the same as the code below?
> > > > 
> > > >   if (!In<ELFT>::Verdef)
> > > >     return true;
> > > >   return In<ELFT>::VerNeed->empty();
> > > It is the same as:
> > > 
> > > ```
> > > template <class ELFT> bool VersionTableSection<ELFT>::empty() const {
> > >   return !In<ELFT>::VerDef && In<ELFT>::VerNeed->empty();
> > > }
> > > ```
> > So, you meant VersionTable is empty if
> > 
> >  - we have a VerDef section,
> >  - and VerNeed is empty.
> > 
> > But why?
> Mmm, no, it is empty if
>   - we **do not** have Verdef
>   - and VerNeed is empty.
> 
> 
Then

  if (In<ELFT>::VerDef == nullptr)
    return true;
  return In<ELFT>::VerNeed->empty();

This is the same code as I wrote in the first comment.


https://reviews.llvm.org/D27040