[PATCH] D39058: [ELF] - Simplify reporting of garbage collected sections.

[Rui Ueyama via Phabricator via llvm-commits]

ruiu added inline comments.


================
Comment at: ELF/LinkerScript.cpp:286
     for (InputSectionBase *Sec : InputSections) {
-      if (Sec->Assigned)
+      if (Sec->Assigned || !Sec->Live)
         continue;
----------------
grimar wrote:
> ruiu wrote:
> > grimar wrote:
> > > ruiu wrote:
> > > > Question: is it possible that a section is assigned to some output section but is not live? It sounds like a bad state to me.
> > > Yes, it is possible for following case:
> > > `/DISCARD/ : {*(.text*)}`
> > > Here we set Assigned flag for .text. It is probably OK it seems ?
> > > 
> > > (I would probably try to completely get rid of 'Assigned' flag, I think we should be able to do that).
> > No, I don't think that is OK. `/DISCARD/` is a keyword and not a real section. Sections discarded by `/DISCARD/` should be not Assigned and not Live.
> I think that is fine because specification explicitly mentions that input sections are assigned:
> 
> > 
> > The special output section name ‘/DISCARD/’ may be used to discard input sections. Any
> > input sections which are assigned to an output section named ‘/DISCARD/’ are not included
> > in the output file.
> (https://sourceware.org/binutils/docs-2.16/ld/Output-Section-Discarding.html)
> 
> Anyways I believe nice way to solve this would be to remove Assigned flag, 
> what should be possible and should be done in different patch.
> 
> 
I don't think that is fine, please read my commit message for r316622. Can you rebase this patch?


https://reviews.llvm.org/D39058