Maintain maximum alignment for common symbols. Warn reducing alignment for
authorNick Clifton <nickc@redhat.com>
Mon, 14 Apr 2003 11:06:25 +0000 (11:06 +0000)
committerNick Clifton <nickc@redhat.com>
Mon, 14 Apr 2003 11:06:25 +0000 (11:06 +0000)
common symbols. Report old filename when symbol size changes.

bfd/ChangeLog
bfd/elflink.h

index d72ec9e6bfdc9284eb7847af8997c35d9979b6e4..a1fef7ea0604d0a08d4b6ac0b468e350207b584e 100644 (file)
@@ -1,3 +1,9 @@
+2003-04-14  H.J. Lu <hjl@gnu.org>
+
+       * elflink.h (elf_link_add_object_symbols): Maintain maximum
+       alignment for common symbols. Warn reducing alignment for
+       common symbols. Report old filename when symbol size changes.
+
 2003-04-12  Alexandre Oliva  <aoliva@redhat.com>
 
        * elfxx-mips.c (mips_elf_calculate_relocation): Adjust two other
index 3535da5547a22305076b089e549c41341e3dc2ca..780e341d42cc39ad72f6aedf76c700e709f72650 100644 (file)
@@ -1609,10 +1609,12 @@ elf_link_add_object_symbols (abfd, info)
       const char *name;
       struct elf_link_hash_entry *h;
       bfd_boolean definition;
-      bfd_boolean size_change_ok, type_change_ok;
+      bfd_boolean size_change_ok;
+      bfd_boolean type_change_ok;
       bfd_boolean new_weakdef;
-      unsigned int old_alignment;
       bfd_boolean override;
+      unsigned int old_alignment;
+      bfd *old_bfd;
 
       override = FALSE;
 
@@ -1717,6 +1719,8 @@ elf_link_add_object_symbols (abfd, info)
       size_change_ok = FALSE;
       type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
       old_alignment = 0;
+      old_bfd = NULL;
+
       if (info->hash->creator->flavour == bfd_target_elf_flavour)
        {
          Elf_Internal_Versym iver;
@@ -1834,9 +1838,23 @@ elf_link_add_object_symbols (abfd, info)
             that we don't reduce the alignment later on.  We can't
             check later, because _bfd_generic_link_add_one_symbol
             will set a default for the alignment which we want to
-            override.  */
-         if (h->root.type == bfd_link_hash_common)
-           old_alignment = h->root.u.c.p->alignment_power;
+            override. We also remember the old bfd where the existing
+            definition comes from.  */
+         switch (h->root.type)
+           {
+           default:
+             break;
+
+           case bfd_link_hash_defined:
+           case bfd_link_hash_defweak:
+             old_bfd = h->root.u.def.section->owner;
+             break;
+           
+           case bfd_link_hash_common:
+             old_bfd = h->root.u.c.p->section->owner;
+             old_alignment = h->root.u.c.p->alignment_power;
+             break;
+           }
 
          if (elf_tdata (abfd)->verdef != NULL
              && ! override
@@ -1893,6 +1911,8 @@ elf_link_add_object_symbols (abfd, info)
                 is specified and no other alignments have been specified.  */
              || (isym->st_value == 1 && old_alignment == 0))
            h->root.u.c.p->alignment_power = align;
+         else
+           h->root.u.c.p->alignment_power = old_alignment;
        }
 
       if (info->hash->creator->flavour == bfd_target_elf_flavour)
@@ -1901,15 +1921,50 @@ elf_link_add_object_symbols (abfd, info)
          bfd_boolean dynsym;
          int new_flag;
 
+         /* Check the alignment when a common symbol is involved. This
+            can change when a common symbol is overriden by a normal
+            definition or a common symbol is ignored due to the old
+            normal definition. We need to make sure the maximum
+            alignment is maintained.  */
+         if ((old_alignment || isym->st_shndx == SHN_COMMON)
+             && h->root.type != bfd_link_hash_common)
+           {
+             unsigned int common_align, normal_align, symbol_align;
+
+             symbol_align = ffs (h->root.u.def.value) - 1;
+             if ((h->root.u.def.section->owner->flags & DYNAMIC) == 0)
+               {
+                 normal_align = h->root.u.def.section->alignment_power;
+                 if (normal_align > symbol_align)
+                   normal_align = symbol_align;
+               }
+             else
+               normal_align = symbol_align;
+
+             if (old_alignment)
+               common_align = old_alignment;
+             else
+               common_align = bfd_log2 (isym->st_value);
+
+             if (normal_align < common_align)
+               (*_bfd_error_handler)
+                 (_("Warning: alignment %u of symbol `%s' in %s is smaller than %u in %s"),
+                  1 << normal_align, name,
+                  bfd_archive_filename (old_bfd),
+                  1 << common_align, bfd_archive_filename (abfd));
+           }
+
          /* Remember the symbol size and type.  */
          if (isym->st_size != 0
              && (definition || h->size == 0))
            {
              if (h->size != 0 && h->size != isym->st_size && ! size_change_ok)
                (*_bfd_error_handler)
-                 (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
+                 (_("Warning: size of symbol `%s' changed from %lu in %s to %lu in %s"),
                   name, (unsigned long) h->size,
-                  (unsigned long) isym->st_size, bfd_archive_filename (abfd));
+                  bfd_archive_filename (old_bfd),
+                  (unsigned long) isym->st_size,
+                  bfd_archive_filename (abfd));
 
              h->size = isym->st_size;
            }