m68k: Check UNDEFWEAK_NO_DYNAMIC_RELOC

Don't generate dynamic relocation against weak undefined symbol if it
is resolved to zero.  FIXME: UNDEFWEAK_NO_DYNAMIC_RELOC may need to be
checked in more places.

	PR ld/22269
	* elf32-m68k.c (elf_m68k_check_relocs): Don't allocate dynamic
	relocations if UNDEFWEAK_NO_DYNAMIC_RELOC is true.
	(elf_m68k_adjust_dynamic_symbol): Don't make symbol dynamic if
	UNDEFWEAK_NO_DYNAMIC_RELOC is true.
	(elf_m68k_relocate_section): Don't generate dynamic relocation
	if UNDEFWEAK_NO_DYNAMIC_RELOC is true.

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 34dde75c1d857a4b131bc2c5c4d4278551a8ad12..90a85a751ea51356e879aeb91d26a560767ba86c 100644 (file)
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,13 @@
+2017-10-14  H.J. Lu  <hongjiu.lu@intel.com>
+
+       PR ld/22269
+       * elf32-m68k.c (elf_m68k_check_relocs): Don't allocate dynamic
+       relocations if UNDEFWEAK_NO_DYNAMIC_RELOC is true.
+       (elf_m68k_adjust_dynamic_symbol): Don't make symbol dynamic if
+       UNDEFWEAK_NO_DYNAMIC_RELOC is true.
+       (elf_m68k_relocate_section): Don't generate dynamic relocation
+       if UNDEFWEAK_NO_DYNAMIC_RELOC is true.
+
 2017-10-14  H.J. Lu  <hongjiu.lu@intel.com>
 
        PR ld/22269

diff --git a/bfd/elf32-m68k.c b/bfd/elf32-m68k.c
index 21bff66ab4037a2e27a533b1d53006be6c160054..501190db12e11c9ba088c0bb42a89a1741cdca9d 100644 (file)
--- a/bfd/elf32-m68k.c
+++ b/bfd/elf32-m68k.c
@@ -2773,7 +2773,9 @@ elf_m68k_check_relocs (bfd *abfd,
 
          /* If we are creating a shared library, we need to copy the
             reloc into the shared library.  */
-         if (bfd_link_pic (info))
+         if (bfd_link_pic (info)
+             && (h == NULL
+                 || !UNDEFWEAK_NO_DYNAMIC_RELOC (info, h)))
            {
              /* When creating a shared object, we must copy these
                 reloc types into the output file.  We create a reloc
@@ -3095,7 +3097,8 @@ elf_m68k_adjust_dynamic_symbol (struct bfd_link_info *info,
     {
       if ((h->plt.refcount <= 0
            || SYMBOL_CALLS_LOCAL (info, h)
-          || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
+          || ((ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
+               || UNDEFWEAK_NO_DYNAMIC_RELOC (info, h))
               && h->root.type == bfd_link_hash_undefweak))
          /* We must always create the plt entry if it was referenced
             by a PLTxxO relocation.  In this case we already recorded
@@ -3622,6 +3625,7 @@ elf_m68k_relocate_section (bfd *output_bfd,
       bfd_vma relocation;
       bfd_boolean unresolved_reloc;
       bfd_reloc_status_type r;
+      bfd_boolean resolved_to_zero;
 
       r_type = ELF32_R_TYPE (rel->r_info);
       if (r_type < 0 || r_type >= (int) R_68K_max)
@@ -3661,6 +3665,9 @@ elf_m68k_relocate_section (bfd *output_bfd,
       if (bfd_link_relocatable (info))
        continue;
 
+      resolved_to_zero = (h != NULL
+                         && UNDEFWEAK_NO_DYNAMIC_RELOC (info, h));
+
       switch (r_type)
        {
        case R_68K_GOT8:
@@ -3785,7 +3792,8 @@ elf_m68k_relocate_section (bfd *output_bfd,
                                                          h)
                        || (bfd_link_pic (info)
                            && SYMBOL_REFERENCES_LOCAL (info, h))
-                       || (ELF_ST_VISIBILITY (h->other)
+                       || ((ELF_ST_VISIBILITY (h->other)
+                            || resolved_to_zero)
                            && h->root.type == bfd_link_hash_undefweak))
                      {
                        /* This is actually a static link, or it is a
@@ -3954,7 +3962,8 @@ elf_m68k_relocate_section (bfd *output_bfd,
              && r_symndx != STN_UNDEF
              && (input_section->flags & SEC_ALLOC) != 0
              && (h == NULL
-                 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
+                 || (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
+                     && !resolved_to_zero)
                  || h->root.type != bfd_link_hash_undefweak)
              && ((r_type != R_68K_PC8
                   && r_type != R_68K_PC16