aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorH.J. Lu <hjl.tools@gmail.com>2001-11-30 15:50:56 +0000
committerH.J. Lu <hjl.tools@gmail.com>2001-11-30 15:50:56 +0000
commit215007a64883740af82c24537ecf5641163159f2 (patch)
treec04db2f0236c98db1a8599a276fe37bd4700ffff
parent82e03011ac9a7bc82eb4496f424c5347350e8b25 (diff)
downloadgdb-215007a64883740af82c24537ecf5641163159f2.zip
gdb-215007a64883740af82c24537ecf5641163159f2.tar.gz
gdb-215007a64883740af82c24537ecf5641163159f2.tar.bz2
2001-11-30 H.J. Lu <hjl@gnu.org>
* elflink.h (elf_add_default_symbol): New. (elf_link_add_object_symbols): Call elf_add_default_symbol () to create an indirect symbol from the default for the symbol with the default version if needed.
-rw-r--r--bfd/ChangeLog7
-rw-r--r--bfd/elflink.h468
2 files changed, 261 insertions, 214 deletions
diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 599f5f0..420fe6f 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,10 @@
+2001-11-30 H.J. Lu <hjl@gnu.org>
+
+ * elflink.h (elf_add_default_symbol): New.
+ (elf_link_add_object_symbols): Call elf_add_default_symbol ()
+ to create an indirect symbol from the default for the symbol
+ with the default version if needed.
+
2001-11-29 "Peter.Schauer" <Peter.Schauer@regent.e-technik.tu-muenchen.de>
* elf.c (elfcore_grok_prstatus): Do not overwite the core signal
diff --git a/bfd/elflink.h b/bfd/elflink.h
index c01e03d..d78832d 100644
--- a/bfd/elflink.h
+++ b/bfd/elflink.h
@@ -39,9 +39,14 @@ static boolean elf_link_add_object_symbols
static boolean elf_link_add_archive_symbols
PARAMS ((bfd *, struct bfd_link_info *));
static boolean elf_merge_symbol
- PARAMS ((bfd *, struct bfd_link_info *, const char *, Elf_Internal_Sym *,
- asection **, bfd_vma *, struct elf_link_hash_entry **,
- boolean *, boolean *, boolean *, boolean));
+ PARAMS ((bfd *, struct bfd_link_info *, const char *,
+ Elf_Internal_Sym *, asection **, bfd_vma *,
+ struct elf_link_hash_entry **, boolean *, boolean *,
+ boolean *, boolean));
+static boolean elf_add_default_symbol
+ PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *,
+ const char *, Elf_Internal_Sym *, asection **, bfd_vma *,
+ boolean *, boolean, boolean));
static boolean elf_export_symbol
PARAMS ((struct elf_link_hash_entry *, PTR));
static boolean elf_finalize_dynstr
@@ -894,6 +899,243 @@ elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
return true;
}
+/* This function is called to create an indirect symbol from the
+ default for the symbol with the default version if needed. The
+ symbol is described by H, NAME, SYM, SEC, VALUE, and OVERRIDE. We
+ set DYNSYM if the new indirect symbol is dynamic. DT_NEEDED
+ indicates if it comes from a DT_NEEDED entry of a shared object. */
+
+static boolean
+elf_add_default_symbol (abfd, info, h, name, sym, sec, value,
+ dynsym, override, dt_needed)
+ bfd *abfd;
+ struct bfd_link_info *info;
+ struct elf_link_hash_entry *h;
+ const char *name;
+ Elf_Internal_Sym *sym;
+ asection **sec;
+ bfd_vma *value;
+ boolean *dynsym;
+ boolean override;
+ boolean dt_needed;
+{
+ boolean type_change_ok;
+ boolean size_change_ok;
+ char *shortname;
+ struct elf_link_hash_entry *hi;
+ struct elf_backend_data *bed;
+ boolean collect;
+ boolean dynamic;
+ char *p;
+
+ /* If this symbol has a version, and it is the default version, we
+ create an indirect symbol from the default name to the fully
+ decorated name. This will cause external references which do not
+ specify a version to be bound to this version of the symbol. */
+ p = strchr (name, ELF_VER_CHR);
+ if (p == NULL || p[1] != ELF_VER_CHR)
+ return true;
+
+ if (override)
+ {
+ /* We are overridden by an old defition. We need to check if we
+ need to crreate the indirect symbol from the default name. */
+ hi = elf_link_hash_lookup (elf_hash_table (info), name, true,
+ false, false);
+ BFD_ASSERT (hi != NULL);
+ if (hi == h)
+ return true;
+ while (hi->root.type == bfd_link_hash_indirect
+ || hi->root.type == bfd_link_hash_warning)
+ {
+ hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
+ if (hi == h)
+ return true;
+ }
+ }
+
+ bed = get_elf_backend_data (abfd);
+ collect = bed->collect;
+ dynamic = (abfd->flags & DYNAMIC) != 0;
+
+ shortname = bfd_hash_allocate (&info->hash->table,
+ (size_t) (p - name + 1));
+ if (shortname == NULL)
+ return false;
+ strncpy (shortname, name, (size_t) (p - name));
+ shortname [p - name] = '\0';
+
+ /* We are going to create a new symbol. Merge it with any existing
+ symbol with this name. For the purposes of the merge, act as
+ though we were defining the symbol we just defined, although we
+ actually going to define an indirect symbol. */
+ type_change_ok = false;
+ size_change_ok = false;
+ if (! elf_merge_symbol (abfd, info, shortname, sym, sec, value,
+ &hi, &override, &type_change_ok,
+ &size_change_ok, dt_needed))
+ return false;
+
+ if (! override)
+ {
+ if (! (_bfd_generic_link_add_one_symbol
+ (info, abfd, shortname, BSF_INDIRECT, bfd_ind_section_ptr,
+ (bfd_vma) 0, name, false, collect,
+ (struct bfd_link_hash_entry **) &hi)))
+ return false;
+ }
+ else
+ {
+ /* In this case the symbol named SHORTNAME is overriding the
+ indirect symbol we want to add. We were planning on making
+ SHORTNAME an indirect symbol referring to NAME. SHORTNAME
+ is the name without a version. NAME is the fully versioned
+ name, and it is the default version.
+
+ Overriding means that we already saw a definition for the
+ symbol SHORTNAME in a regular object, and it is overriding
+ the symbol defined in the dynamic object.
+
+ When this happens, we actually want to change NAME, the
+ symbol we just added, to refer to SHORTNAME. This will cause
+ references to NAME in the shared object to become references
+ to SHORTNAME in the regular object. This is what we expect
+ when we override a function in a shared object: that the
+ references in the shared object will be mapped to the
+ definition in the regular object. */
+
+ while (hi->root.type == bfd_link_hash_indirect
+ || hi->root.type == bfd_link_hash_warning)
+ hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
+
+ h->root.type = bfd_link_hash_indirect;
+ h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
+ if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
+ {
+ h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
+ hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
+ if (hi->elf_link_hash_flags
+ & (ELF_LINK_HASH_REF_REGULAR
+ | ELF_LINK_HASH_DEF_REGULAR))
+ {
+ if (! _bfd_elf_link_record_dynamic_symbol (info, hi))
+ return false;
+ }
+ }
+
+ /* Now set HI to H, so that the following code will set the
+ other fields correctly. */
+ hi = h;
+ }
+
+ /* If there is a duplicate definition somewhere, then HI may not
+ point to an indirect symbol. We will have reported an error to
+ the user in that case. */
+
+ if (hi->root.type == bfd_link_hash_indirect)
+ {
+ struct elf_link_hash_entry *ht;
+
+ /* If the symbol became indirect, then we assume that we have
+ not seen a definition before. */
+ BFD_ASSERT ((hi->elf_link_hash_flags
+ & (ELF_LINK_HASH_DEF_DYNAMIC
+ | ELF_LINK_HASH_DEF_REGULAR)) == 0);
+
+ ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
+ (*bed->elf_backend_copy_indirect_symbol) (ht, hi);
+
+ /* See if the new flags lead us to realize that the symbol must
+ be dynamic. */
+ if (! *dynsym)
+ {
+ if (! dynamic)
+ {
+ if (info->shared
+ || ((hi->elf_link_hash_flags
+ & ELF_LINK_HASH_REF_DYNAMIC) != 0))
+ *dynsym = true;
+ }
+ else
+ {
+ if ((hi->elf_link_hash_flags
+ & ELF_LINK_HASH_REF_REGULAR) != 0)
+ *dynsym = true;
+ }
+ }
+ }
+
+ /* We also need to define an indirection from the nondefault version
+ of the symbol. */
+
+ shortname = bfd_hash_allocate (&info->hash->table, strlen (name));
+ if (shortname == NULL)
+ return false;
+ strncpy (shortname, name, (size_t) (p - name));
+ strcpy (shortname + (p - name), p + 1);
+
+ /* Once again, merge with any existing symbol. */
+ type_change_ok = false;
+ size_change_ok = false;
+ if (! elf_merge_symbol (abfd, info, shortname, sym, sec, value,
+ &hi, &override, &type_change_ok,
+ &size_change_ok, dt_needed))
+ return false;
+
+ if (override)
+ {
+ /* Here SHORTNAME is a versioned name, so we don't expect to see
+ the type of override we do in the case above. */
+ (*_bfd_error_handler)
+ (_("%s: warning: unexpected redefinition of `%s'"),
+ bfd_archive_filename (abfd), shortname);
+ }
+ else
+ {
+ if (! (_bfd_generic_link_add_one_symbol
+ (info, abfd, shortname, BSF_INDIRECT,
+ bfd_ind_section_ptr, (bfd_vma) 0, name, false,
+ collect, (struct bfd_link_hash_entry **) &hi)))
+ return false;
+
+ /* If there is a duplicate definition somewhere, then HI may not
+ point to an indirect symbol. We will have reported an error
+ to the user in that case. */
+
+ if (hi->root.type == bfd_link_hash_indirect)
+ {
+ /* If the symbol became indirect, then we assume that we have
+ not seen a definition before. */
+ BFD_ASSERT ((hi->elf_link_hash_flags
+ & (ELF_LINK_HASH_DEF_DYNAMIC
+ | ELF_LINK_HASH_DEF_REGULAR)) == 0);
+
+ (*bed->elf_backend_copy_indirect_symbol) (h, hi);
+
+ /* See if the new flags lead us to realize that the symbol
+ must be dynamic. */
+ if (! *dynsym)
+ {
+ if (! dynamic)
+ {
+ if (info->shared
+ || ((hi->elf_link_hash_flags
+ & ELF_LINK_HASH_REF_DYNAMIC) != 0))
+ *dynsym = true;
+ }
+ else
+ {
+ if ((hi->elf_link_hash_flags
+ & ELF_LINK_HASH_REF_REGULAR) != 0)
+ *dynsym = true;
+ }
+ }
+ }
+ }
+
+ return true;
+}
+
/* Add symbols from an ELF object file to the linker hash table. */
static boolean
@@ -1373,6 +1615,9 @@ elf_link_add_object_symbols (abfd, info)
boolean size_change_ok, type_change_ok;
boolean new_weakdef;
unsigned int old_alignment;
+ boolean override;
+
+ override = false;
elf_swap_symbol_in (abfd, esym, &sym);
@@ -1463,7 +1708,6 @@ elf_link_add_object_symbols (abfd, info)
{
Elf_Internal_Versym iver;
unsigned int vernum = 0;
- boolean override;
if (ever != NULL)
{
@@ -1735,217 +1979,13 @@ elf_link_add_object_symbols (abfd, info)
h->elf_link_hash_flags |= new_flag;
- /* If this symbol has a version, and it is the default
- version, we create an indirect symbol from the default
- name to the fully decorated name. This will cause
- external references which do not specify a version to be
- bound to this version of the symbol. */
+ /* Check to see if we need to add an indirect symbol for
+ the default name. */
if (definition || h->root.type == bfd_link_hash_common)
- {
- char *p;
-
- p = strchr (name, ELF_VER_CHR);
- if (p != NULL && p[1] == ELF_VER_CHR)
- {
- char *shortname;
- struct elf_link_hash_entry *hi;
- boolean override;
-
- shortname = bfd_hash_allocate (&info->hash->table,
- (size_t) (p - name + 1));
- if (shortname == NULL)
- goto error_return;
- strncpy (shortname, name, (size_t) (p - name));
- shortname[p - name] = '\0';
-
- /* We are going to create a new symbol. Merge it
- with any existing symbol with this name. For the
- purposes of the merge, act as though we were
- defining the symbol we just defined, although we
- actually going to define an indirect symbol. */
- type_change_ok = false;
- size_change_ok = false;
- if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
- &value, &hi, &override,
- &type_change_ok,
- &size_change_ok, dt_needed))
- goto error_return;
-
- if (! override)
- {
- if (! (_bfd_generic_link_add_one_symbol
- (info, abfd, shortname, BSF_INDIRECT,
- bfd_ind_section_ptr, (bfd_vma) 0, name, false,
- collect, (struct bfd_link_hash_entry **) &hi)))
- goto error_return;
- }
- else
- {
- /* In this case the symbol named SHORTNAME is
- overriding the indirect symbol we want to
- add. We were planning on making SHORTNAME an
- indirect symbol referring to NAME. SHORTNAME
- is the name without a version. NAME is the
- fully versioned name, and it is the default
- version.
-
- Overriding means that we already saw a
- definition for the symbol SHORTNAME in a
- regular object, and it is overriding the
- symbol defined in the dynamic object.
-
- When this happens, we actually want to change
- NAME, the symbol we just added, to refer to
- SHORTNAME. This will cause references to
- NAME in the shared object to become
- references to SHORTNAME in the regular
- object. This is what we expect when we
- override a function in a shared object: that
- the references in the shared object will be
- mapped to the definition in the regular
- object. */
-
- while (hi->root.type == bfd_link_hash_indirect
- || hi->root.type == bfd_link_hash_warning)
- hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
-
- h->root.type = bfd_link_hash_indirect;
- h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
- if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
- {
- h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
- hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
- if (hi->elf_link_hash_flags
- & (ELF_LINK_HASH_REF_REGULAR
- | ELF_LINK_HASH_DEF_REGULAR))
- {
- if (! _bfd_elf_link_record_dynamic_symbol (info,
- hi))
- goto error_return;
- }
- }
-
- /* Now set HI to H, so that the following code
- will set the other fields correctly. */
- hi = h;
- }
-
- /* If there is a duplicate definition somewhere,
- then HI may not point to an indirect symbol. We
- will have reported an error to the user in that
- case. */
-
- if (hi->root.type == bfd_link_hash_indirect)
- {
- struct elf_link_hash_entry *ht;
-
- /* If the symbol became indirect, then we assume
- that we have not seen a definition before. */
- BFD_ASSERT ((hi->elf_link_hash_flags
- & (ELF_LINK_HASH_DEF_DYNAMIC
- | ELF_LINK_HASH_DEF_REGULAR))
- == 0);
-
- ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
- (*bed->elf_backend_copy_indirect_symbol) (ht, hi);
-
- /* See if the new flags lead us to realize that
- the symbol must be dynamic. */
- if (! dynsym)
- {
- if (! dynamic)
- {
- if (info->shared
- || ((hi->elf_link_hash_flags
- & ELF_LINK_HASH_REF_DYNAMIC)
- != 0))
- dynsym = true;
- }
- else
- {
- if ((hi->elf_link_hash_flags
- & ELF_LINK_HASH_REF_REGULAR) != 0)
- dynsym = true;
- }
- }
- }
-
- /* We also need to define an indirection from the
- nondefault version of the symbol. */
-
- shortname = bfd_hash_allocate (&info->hash->table,
- strlen (name));
- if (shortname == NULL)
- goto error_return;
- strncpy (shortname, name, (size_t) (p - name));
- strcpy (shortname + (p - name), p + 1);
-
- /* Once again, merge with any existing symbol. */
- type_change_ok = false;
- size_change_ok = false;
- if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
- &value, &hi, &override,
- &type_change_ok,
- &size_change_ok, dt_needed))
- goto error_return;
-
- if (override)
- {
- /* Here SHORTNAME is a versioned name, so we
- don't expect to see the type of override we
- do in the case above. */
- (*_bfd_error_handler)
- (_("%s: warning: unexpected redefinition of `%s'"),
- bfd_archive_filename (abfd), shortname);
- }
- else
- {
- if (! (_bfd_generic_link_add_one_symbol
- (info, abfd, shortname, BSF_INDIRECT,
- bfd_ind_section_ptr, (bfd_vma) 0, name, false,
- collect, (struct bfd_link_hash_entry **) &hi)))
- goto error_return;
-
- /* If there is a duplicate definition somewhere,
- then HI may not point to an indirect symbol.
- We will have reported an error to the user in
- that case. */
-
- if (hi->root.type == bfd_link_hash_indirect)
- {
- /* If the symbol became indirect, then we
- assume that we have not seen a definition
- before. */
- BFD_ASSERT ((hi->elf_link_hash_flags
- & (ELF_LINK_HASH_DEF_DYNAMIC
- | ELF_LINK_HASH_DEF_REGULAR))
- == 0);
-
- (*bed->elf_backend_copy_indirect_symbol) (h, hi);
-
- /* See if the new flags lead us to realize
- that the symbol must be dynamic. */
- if (! dynsym)
- {
- if (! dynamic)
- {
- if (info->shared
- || ((hi->elf_link_hash_flags
- & ELF_LINK_HASH_REF_DYNAMIC)
- != 0))
- dynsym = true;
- }
- else
- {
- if ((hi->elf_link_hash_flags
- & ELF_LINK_HASH_REF_REGULAR) != 0)
- dynsym = true;
- }
- }
- }
- }
- }
- }
+ if (! elf_add_default_symbol (abfd, info, h, name, &sym,
+ &sec, &value, &dynsym,
+ override, dt_needed))
+ goto error_return;
if (dynsym && h->dynindx == -1)
{