PR22431, powerpc64 ld segfault when .plt discarded

The fix for the PR is to not use input_section->output_section->owner
to get to the output bfd, but use the output bfd directly since it is
available nowadays in struct bfd_link_info.

I thought it worth warning when non-empty dynamic sections are
discarded too, which meant a tweak to one of the ld tests to avoid the
warning.

bfd/
	PR 22431
	* elf64-ppc.c (ppc64_elf_size_dynamic_sections): Warn on discarding
	non-empty dynamic section.
	(ppc_build_one_stub): Take elf_gp from output bfd, not output
	section owner.
	(ppc_size_one_stub, ppc64_elf_next_toc_section): Likewise.
ld/
	* testsuite/ld-elf/note-3.t: Don't discard .got.

(cherry picked from commit 06bcf5416feae129e239476ab1408e038bba171d)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 4ad3675763aea164e02b46967951b82c22e7d32d..c8bcf8eabe02e145b5dd28d5fe2a4c6285b2d622 100644 (file)
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,14 @@
+2017-11-24  Alan Modra  <amodra@gmail.com>
+
+       Apply from master
+       2017-11-14  Alan Modra  <amodra@gmail.com>
+       PR 22431
+       * elf64-ppc.c (ppc64_elf_size_dynamic_sections): Warn on discarding
+       non-empty dynamic section.
+       (ppc_build_one_stub): Take elf_gp from output bfd, not output
+       section owner.
+       (ppc_size_one_stub, ppc64_elf_next_toc_section): Likewise.
+
 2017-11-05  Alan Modra  <amodra@gmail.com>
 
        PR 22397

diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c
index 3c8e2865d79de3cefa822a9cf9dc4fda0798d39d..e2d4ba15e51d5d07b0e90e9c9361273c22fd3e20 100644 (file)
--- a/bfd/elf64-ppc.c
+++ b/bfd/elf64-ppc.c
@@ -10329,6 +10329,10 @@ ppc64_elf_size_dynamic_sections (bfd *output_bfd,
          continue;
        }
 
+      if (bfd_is_abs_section (s->output_section))
+       _bfd_error_handler (_("warning: discarding dynamic section %s"),
+                           s->name);
+
       if ((s->flags & SEC_HAS_CONTENTS) == 0)
        continue;
 
@@ -11123,7 +11127,7 @@ ppc_build_one_stub (struct bfd_hash_entry *gen_entry, void *in_arg)
              + htab->brlt->output_section->vma);
 
       off = (dest
-            - elf_gp (htab->brlt->output_section->owner)
+            - elf_gp (info->output_bfd)
             - htab->sec_info[stub_entry->group->link_sec->id].toc_off);
 
       if (off + 0x80008000 > 0xffffffff || (off & 7) != 0)
@@ -11274,7 +11278,7 @@ ppc_build_one_stub (struct bfd_hash_entry *gen_entry, void *in_arg)
        }
 
       off = (dest
-            - elf_gp (plt->output_section->owner)
+            - elf_gp (info->output_bfd)
             - htab->sec_info[stub_entry->group->link_sec->id].toc_off);
 
       if (off + 0x80008000 > 0xffffffff || (off & 7) != 0)
@@ -11422,7 +11426,7 @@ ppc_size_one_stub (struct bfd_hash_entry *gen_entry, void *in_arg)
        plt = htab->elf.iplt;
       off += (plt->output_offset
              + plt->output_section->vma
-             - elf_gp (plt->output_section->owner)
+             - elf_gp (info->output_bfd)
              - htab->sec_info[stub_entry->group->link_sec->id].toc_off);
 
       size = plt_stub_size (htab, stub_entry, off);
@@ -11525,7 +11529,7 @@ ppc_size_one_stub (struct bfd_hash_entry *gen_entry, void *in_arg)
          off = (br_entry->offset
                 + htab->brlt->output_offset
                 + htab->brlt->output_section->vma
-                - elf_gp (htab->brlt->output_section->owner)
+                - elf_gp (info->output_bfd)
                 - htab->sec_info[stub_entry->group->link_sec->id].toc_off);
 
          if (info->emitrelocations)
@@ -11645,7 +11649,7 @@ ppc64_elf_next_toc_section (struct bfd_link_info *info, asection *isec)
         output toc base plus 0x8000.  Making the input elf_gp an
         offset allows us to move the toc as a whole without
         recalculating input elf_gp.  */
-      off = htab->toc_curr - elf_gp (isec->output_section->owner);
+      off = htab->toc_curr - elf_gp (info->output_bfd);
       off += TOC_BASE_OFF;
 
       /* Die if someone uses a linker script that doesn't keep input
@@ -11674,7 +11678,7 @@ ppc64_elf_next_toc_section (struct bfd_link_info *info, asection *isec)
     }
   addr = (htab->toc_first_sec->output_offset
          + htab->toc_first_sec->output_section->vma);
-  off = addr - elf_gp (isec->output_section->owner) + TOC_BASE_OFF;
+  off = addr - elf_gp (info->output_bfd) + TOC_BASE_OFF;
   elf_gp (isec->owner) = off;
 
   return TRUE;

diff --git a/ld/ChangeLog b/ld/ChangeLog
index 364b1040ec6febd0dba37e857e2e9c64b840b941..0415ea9777cd58c88de6720face5bc4e52b45a29 100644 (file)
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,9 @@
+2017-11-24  Alan Modra  <amodra@gmail.com>
+
+       Apply from master
+       2017-11-14  Alan Modra  <amodra@gmail.com>
+       * testsuite/ld-elf/note-3.t: Don't discard .got.
+
 2017-11-01  Alan Modra  <amodra@gmail.com>
 
        Apply from master

diff --git a/ld/testsuite/ld-elf/note-3.t b/ld/testsuite/ld-elf/note-3.t
index 13324ae5470a3bb960e8a31e0587f9f2535ae643..4c617d8f2a09803f2f479147e83163f40b007bf6 100644 (file)
--- a/ld/testsuite/ld-elf/note-3.t
+++ b/ld/testsuite/ld-elf/note-3.t
@@ -17,6 +17,7 @@ SECTIONS
   
   .dynstr : { *(.dynstr) }
   .dynsym : { *(.dynsym) }
+  .got : { *(.got .toc) *(.igot) }
   .got.plt : { *(.got.plt) *(.igot.plt) }
   /DISCARD/ : { *(*) }
 }