[Bug lto/82757] [8 regression] r251560 causes: plugin needed to handle lto object

[rguenther at suse dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82757

--- Comment #6 from rguenther at suse dot de <rguenther at suse dot de> ---
On Mon, 30 Oct 2017, amodra at gmail dot com wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82757
> 
> --- Comment #5 from Alan Modra <amodra at gmail dot com> ---
> Incidentally, the only reason ld.bfd gets past the "plugin needed" warning is
> that it only warns on a common symbol called __gnu_lto_slim, not an undefined
> one..  Bump st_name by one for __gnu_lto_ symbols, perhaps?

I guess that would work.  We already handle __gnu_lto_ symbols
specially by making them hidden.

Index: libiberty/simple-object-elf.c
===================================================================
--- libiberty/simple-object-elf.c       (revision 254211)
+++ libiberty/simple-object-elf.c       (working copy)
@@ -1384,7 +1384,12 @@ simple_object_elf_copy_lto_debug_section
                                  && p[1] == '_'
                                  && strncmp (p + (p[2] == '_'),
                                              "__gnu_lto_", 10) == 0)
-                               other = STV_HIDDEN;
+                               {
+                                 other = STV_HIDDEN;
+                                 ELF_SET_FIELD (type_functions, ei_class, 
Sym,
+                                                ent, st_name, Elf_Word,
+                                                st_name + 1);
+                               }
                            }
                        }
                      *st_other = other;