- return false;
-}
-
-/* This function is called when we want to define a new symbol. It
- handles the various cases which arise when we find a definition in
- a dynamic object, or when there is already a definition in a
- dynamic object. The new symbol is described by NAME, SYM, PSEC,
- and PVALUE. We set SYM_HASH to the hash table entry. We set
- OVERRIDE if the old symbol is overriding a new definition. We set
- TYPE_CHANGE_OK if it is OK for the type to change. We set
- SIZE_CHANGE_OK if it is OK for the size to change. By OK to
- change, we mean that we shouldn't warn if the type or size does
- change. DT_NEEDED indicates if it comes from a DT_NEEDED entry of
- a shared object. */
-
-static boolean
-elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
- override, type_change_ok, size_change_ok, dt_needed)
- bfd *abfd;
- struct bfd_link_info *info;
- const char *name;
- Elf_Internal_Sym *sym;
- asection **psec;
- bfd_vma *pvalue;
- struct elf_link_hash_entry **sym_hash;
- boolean *override;
- boolean *type_change_ok;
- boolean *size_change_ok;
- boolean dt_needed;
-{
- asection *sec;
- struct elf_link_hash_entry *h;
- int bind;
- bfd *oldbfd;
- boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
-
- *override = false;
-
- sec = *psec;
- bind = ELF_ST_BIND (sym->st_info);
-
- if (! bfd_is_und_section (sec))
- h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
- else
- h = ((struct elf_link_hash_entry *)
- bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
- if (h == NULL)
- return false;
- *sym_hash = h;
-
- /* This code is for coping with dynamic objects, and is only useful
- if we are doing an ELF link. */
- if (info->hash->creator != abfd->xvec)
- return true;
-
- /* For merging, we only care about real symbols. */
-
- while (h->root.type == bfd_link_hash_indirect
- || h->root.type == bfd_link_hash_warning)
- h = (struct elf_link_hash_entry *) h->root.u.i.link;
-
- /* If we just created the symbol, mark it as being an ELF symbol.
- Other than that, there is nothing to do--there is no merge issue
- with a newly defined symbol--so we just return. */
-
- if (h->root.type == bfd_link_hash_new)
- {
- h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
- return true;
- }
-
- /* OLDBFD is a BFD associated with the existing symbol. */
-
- switch (h->root.type)
- {
- default:
- oldbfd = NULL;
- break;
-
- case bfd_link_hash_undefined:
- case bfd_link_hash_undefweak:
- oldbfd = h->root.u.undef.abfd;
- break;
-
- case bfd_link_hash_defined:
- case bfd_link_hash_defweak:
- oldbfd = h->root.u.def.section->owner;
- break;
-
- case bfd_link_hash_common:
- oldbfd = h->root.u.c.p->section->owner;
- break;
- }
-
- /* In cases involving weak versioned symbols, we may wind up trying
- to merge a symbol with itself. Catch that here, to avoid the
- confusion that results if we try to override a symbol with
- itself. The additional tests catch cases like
- _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
- dynamic object, which we do want to handle here. */
- if (abfd == oldbfd
- && ((abfd->flags & DYNAMIC) == 0
- || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0))
- return true;
-
- /* NEWDYN and OLDDYN indicate whether the new or old symbol,
- respectively, is from a dynamic object. */
-
- if ((abfd->flags & DYNAMIC) != 0)
- newdyn = true;
- else
- newdyn = false;
-
- if (oldbfd != NULL)
- olddyn = (oldbfd->flags & DYNAMIC) != 0;
- else
- {
- asection *hsec;
-
- /* This code handles the special SHN_MIPS_{TEXT,DATA} section
- indices used by MIPS ELF. */
- switch (h->root.type)
- {
- default:
- hsec = NULL;
- break;
-
- case bfd_link_hash_defined:
- case bfd_link_hash_defweak:
- hsec = h->root.u.def.section;
- break;
-
- case bfd_link_hash_common:
- hsec = h->root.u.c.p->section;
- break;
- }
-
- if (hsec == NULL)
- olddyn = false;
- else
- olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
- }
-
- /* NEWDEF and OLDDEF indicate whether the new or old symbol,
- respectively, appear to be a definition rather than reference. */
-
- if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
- newdef = false;
- else
- newdef = true;
-
- if (h->root.type == bfd_link_hash_undefined
- || h->root.type == bfd_link_hash_undefweak
- || h->root.type == bfd_link_hash_common)
- olddef = false;
- else
- olddef = true;
-
- /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
- symbol, respectively, appears to be a common symbol in a dynamic
- object. If a symbol appears in an uninitialized section, and is
- not weak, and is not a function, then it may be a common symbol
- which was resolved when the dynamic object was created. We want
- to treat such symbols specially, because they raise special
- considerations when setting the symbol size: if the symbol
- appears as a common symbol in a regular object, and the size in
- the regular object is larger, we must make sure that we use the
- larger size. This problematic case can always be avoided in C,
- but it must be handled correctly when using Fortran shared
- libraries.
-
- Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
- likewise for OLDDYNCOMMON and OLDDEF.
-
- Note that this test is just a heuristic, and that it is quite
- possible to have an uninitialized symbol in a shared object which
- is really a definition, rather than a common symbol. This could
- lead to some minor confusion when the symbol really is a common
- symbol in some regular object. However, I think it will be
- harmless. */
-
- if (newdyn
- && newdef
- && (sec->flags & SEC_ALLOC) != 0
- && (sec->flags & SEC_LOAD) == 0
- && sym->st_size > 0
- && bind != STB_WEAK
- && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
- newdyncommon = true;
- else
- newdyncommon = false;
-
- if (olddyn
- && olddef
- && h->root.type == bfd_link_hash_defined
- && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
- && (h->root.u.def.section->flags & SEC_ALLOC) != 0
- && (h->root.u.def.section->flags & SEC_LOAD) == 0
- && h->size > 0
- && h->type != STT_FUNC)
- olddyncommon = true;
- else
- olddyncommon = false;
-
- /* It's OK to change the type if either the existing symbol or the
- new symbol is weak unless it comes from a DT_NEEDED entry of
- a shared object, in which case, the DT_NEEDED entry may not be
- required at the run time. */
-
- if ((! dt_needed && h->root.type == bfd_link_hash_defweak)
- || h->root.type == bfd_link_hash_undefweak
- || bind == STB_WEAK)
- *type_change_ok = true;
-
- /* It's OK to change the size if either the existing symbol or the
- new symbol is weak, or if the old symbol is undefined. */
-
- if (*type_change_ok
- || h->root.type == bfd_link_hash_undefined)
- *size_change_ok = true;
-
- /* If both the old and the new symbols look like common symbols in a
- dynamic object, set the size of the symbol to the larger of the
- two. */
-
- if (olddyncommon
- && newdyncommon
- && sym->st_size != h->size)
- {
- /* Since we think we have two common symbols, issue a multiple
- common warning if desired. Note that we only warn if the
- size is different. If the size is the same, we simply let
- the old symbol override the new one as normally happens with
- symbols defined in dynamic objects. */
-
- if (! ((*info->callbacks->multiple_common)
- (info, h->root.root.string, oldbfd, bfd_link_hash_common,
- h->size, abfd, bfd_link_hash_common, sym->st_size)))
- return false;
-
- if (sym->st_size > h->size)
- h->size = sym->st_size;
-
- *size_change_ok = true;
- }
-
- /* If we are looking at a dynamic object, and we have found a
- definition, we need to see if the symbol was already defined by
- some other object. If so, we want to use the existing
- definition, and we do not want to report a multiple symbol
- definition error; we do this by clobbering *PSEC to be
- bfd_und_section_ptr.
-
- We treat a common symbol as a definition if the symbol in the
- shared library is a function, since common symbols always
- represent variables; this can cause confusion in principle, but
- any such confusion would seem to indicate an erroneous program or
- shared library. We also permit a common symbol in a regular
- object to override a weak symbol in a shared object.
-
- We prefer a non-weak definition in a shared library to a weak
- definition in the executable unless it comes from a DT_NEEDED
- entry of a shared object, in which case, the DT_NEEDED entry
- may not be required at the run time. */
-
- if (newdyn
- && newdef
- && (olddef
- || (h->root.type == bfd_link_hash_common
- && (bind == STB_WEAK
- || ELF_ST_TYPE (sym->st_info) == STT_FUNC)))
- && (h->root.type != bfd_link_hash_defweak
- || dt_needed
- || bind == STB_WEAK))
- {
- *override = true;
- newdef = false;
- newdyncommon = false;
-
- *psec = sec = bfd_und_section_ptr;
- *size_change_ok = true;
-
- /* If we get here when the old symbol is a common symbol, then
- we are explicitly letting it override a weak symbol or
- function in a dynamic object, and we don't want to warn about
- a type change. If the old symbol is a defined symbol, a type
- change warning may still be appropriate. */
-
- if (h->root.type == bfd_link_hash_common)
- *type_change_ok = true;
- }
-
- /* Handle the special case of an old common symbol merging with a
- new symbol which looks like a common symbol in a shared object.
- We change *PSEC and *PVALUE to make the new symbol look like a
- common symbol, and let _bfd_generic_link_add_one_symbol will do
- the right thing. */
-
- if (newdyncommon
- && h->root.type == bfd_link_hash_common)
- {
- *override = true;
- newdef = false;
- newdyncommon = false;
- *pvalue = sym->st_size;
- *psec = sec = bfd_com_section_ptr;
- *size_change_ok = true;
- }
-
- /* If the old symbol is from a dynamic object, and the new symbol is
- a definition which is not from a dynamic object, then the new
- symbol overrides the old symbol. Symbols from regular files
- always take precedence over symbols from dynamic objects, even if
- they are defined after the dynamic object in the link.
-
- As above, we again permit a common symbol in a regular object to
- override a definition in a shared object if the shared object
- symbol is a function or is weak.
-
- As above, we permit a non-weak definition in a shared object to
- override a weak definition in a regular object. */
-
- if (! newdyn
- && (newdef
- || (bfd_is_com_section (sec)
- && (h->root.type == bfd_link_hash_defweak
- || h->type == STT_FUNC)))
- && olddyn
- && olddef
- && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
- && (bind != STB_WEAK
- || h->root.type == bfd_link_hash_defweak))
- {
- /* Change the hash table entry to undefined, and let
- _bfd_generic_link_add_one_symbol do the right thing with the
- new definition. */
-
- h->root.type = bfd_link_hash_undefined;
- h->root.u.undef.abfd = h->root.u.def.section->owner;
- *size_change_ok = true;
-
- olddef = false;
- olddyncommon = false;
-
- /* We again permit a type change when a common symbol may be
- overriding a function. */
-
- if (bfd_is_com_section (sec))
- *type_change_ok = true;
-
- /* This union may have been set to be non-NULL when this symbol
- was seen in a dynamic object. We must force the union to be
- NULL, so that it is correct for a regular symbol. */
-
- h->verinfo.vertree = NULL;
-
- /* In this special case, if H is the target of an indirection,
- we want the caller to frob with H rather than with the
- indirect symbol. That will permit the caller to redefine the
- target of the indirection, rather than the indirect symbol
- itself. FIXME: This will break the -y option if we store a
- symbol with a different name. */
- *sym_hash = h;
- }
-
- /* Handle the special case of a new common symbol merging with an
- old symbol that looks like it might be a common symbol defined in
- a shared object. Note that we have already handled the case in
- which a new common symbol should simply override the definition
- in the shared library. */
-
- if (! newdyn
- && bfd_is_com_section (sec)
- && olddyncommon)
- {
- /* It would be best if we could set the hash table entry to a
- common symbol, but we don't know what to use for the section
- or the alignment. */
- if (! ((*info->callbacks->multiple_common)
- (info, h->root.root.string, oldbfd, bfd_link_hash_common,
- h->size, abfd, bfd_link_hash_common, sym->st_size)))
- return false;
-
- /* If the predumed common symbol in the dynamic object is
- larger, pretend that the new symbol has its size. */
-
- if (h->size > *pvalue)
- *pvalue = h->size;
-
- /* FIXME: We no longer know the alignment required by the symbol
- in the dynamic object, so we just wind up using the one from
- the regular object. */
-
- olddef = false;
- olddyncommon = false;
-
- h->root.type = bfd_link_hash_undefined;
- h->root.u.undef.abfd = h->root.u.def.section->owner;
-
- *size_change_ok = true;
- *type_change_ok = true;
-
- h->verinfo.vertree = NULL;
- }
-
- /* Handle the special case of a weak definition in a regular object
- followed by a non-weak definition in a shared object. In this
- case, we prefer the definition in the shared object unless it
- comes from a DT_NEEDED entry of a shared object, in which case,
- the DT_NEEDED entry may not be required at the run time. */
- if (olddef
- && ! dt_needed
- && h->root.type == bfd_link_hash_defweak
- && newdef
- && newdyn
- && bind != STB_WEAK)
- {
- /* To make this work we have to frob the flags so that the rest
- of the code does not think we are using the regular
- definition. */
- if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
- h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
- else if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)
- h->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
- h->elf_link_hash_flags &= ~ (ELF_LINK_HASH_DEF_REGULAR
- | ELF_LINK_HASH_DEF_DYNAMIC);
-
- /* If H is the target of an indirection, we want the caller to
- use H rather than the indirect symbol. Otherwise if we are
- defining a new indirect symbol we will wind up attaching it
- to the entry we are overriding. */
- *sym_hash = h;
- }
-
- /* Handle the special case of a non-weak definition in a shared
- object followed by a weak definition in a regular object. In
- this case we prefer to definition in the shared object. To make
- this work we have to tell the caller to not treat the new symbol
- as a definition. */
- if (olddef
- && olddyn
- && h->root.type != bfd_link_hash_defweak
- && newdef
- && ! newdyn
- && bind == STB_WEAK)
- *override = true;
-
- 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;
- size_t len, shortlen;
-
- /* 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 create 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;
-
- shortlen = p - name;
- shortname = bfd_hash_allocate (&info->hash->table, shortlen + 1);
- if (shortname == NULL)
- return false;
- memcpy (shortname, name, shortlen);
- shortname[shortlen] = '\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. */
-
- len = strlen (name);
- shortname = bfd_hash_allocate (&info->hash->table, len);
- if (shortname == NULL)
- return false;
- memcpy (shortname, name, shortlen);
- memcpy (shortname + shortlen, p + 1, len - shortlen);
-
- /* 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;