old-cross-binutils/bfd/linker.c

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/* linker.c -- BFD linker routines
Copyright 1993 Free Software Foundation, Inc.
Written by Steve Chamberlain and Ian Lance Taylor, Cygnus Support
This file is part of BFD
GLD is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GLD is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GLD; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "bfd.h"
#include "sysdep.h"
#include "libbfd.h"
#include "bfdlink.h"
#include "genlink.h"
static struct bfd_hash_entry *generic_link_hash_newfunc
PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *,
const char *));
static boolean generic_link_add_object_symbols
PARAMS ((bfd *, struct bfd_link_info *));
static boolean generic_link_check_archive_element
PARAMS ((bfd *, struct bfd_link_info *, boolean *pneeded));
static boolean generic_link_add_symbol_list
PARAMS ((bfd *, struct bfd_link_info *, bfd_size_type count, asymbol **));
static boolean generic_add_output_symbol
PARAMS ((bfd *, size_t *psymalloc, asymbol *));
static boolean default_fill_link_order
PARAMS ((bfd *, struct bfd_link_info *, asection *,
struct bfd_link_order *));
/* The link hash table structure is defined in bfdlink.h. It provides
a base hash table which the backend specific hash tables are built
upon. */
/* Routine to create an entry in the link hash table. */
struct bfd_hash_entry *
_bfd_link_hash_newfunc (entry, table, string)
struct bfd_hash_entry *entry;
struct bfd_hash_table *table;
const char *string;
{
struct bfd_link_hash_entry *ret = (struct bfd_link_hash_entry *) entry;
/* Allocate the structure if it has not already been allocated by a
subclass. */
if (ret == (struct bfd_link_hash_entry *) NULL)
ret = ((struct bfd_link_hash_entry *)
bfd_hash_allocate (table, sizeof (struct bfd_link_hash_entry)));
/* Call the allocation method of the superclass. */
ret = ((struct bfd_link_hash_entry *)
bfd_hash_newfunc ((struct bfd_hash_entry *) ret, table, string));
/* Initialize the local fields. */
ret->type = bfd_link_hash_new;
ret->written = false;
ret->next = NULL;
return (struct bfd_hash_entry *) ret;
}
/* Initialize a link hash table. The BFD argument is the one
responsible for creating this table. */
boolean
_bfd_link_hash_table_init (table, abfd, newfunc)
struct bfd_link_hash_table *table;
bfd *abfd;
struct bfd_hash_entry *(*newfunc) PARAMS ((struct bfd_hash_entry *,
struct bfd_hash_table *,
const char *));
{
table->creator = abfd->xvec;
table->undefs = NULL;
table->undefs_tail = NULL;
return bfd_hash_table_init (&table->table, newfunc);
}
/* Look up a symbol in a link hash table. If follow is true, we
follow bfd_link_hash_indirect and bfd_link_hash_warning links to
the real symbol. */
struct bfd_link_hash_entry *
bfd_link_hash_lookup (table, string, create, copy, follow)
struct bfd_link_hash_table *table;
const char *string;
boolean create;
boolean copy;
boolean follow;
{
struct bfd_link_hash_entry *ret;
ret = ((struct bfd_link_hash_entry *)
bfd_hash_lookup (&table->table, string, create, copy));
if (follow && ret != (struct bfd_link_hash_entry *) NULL)
{
while (ret->type == bfd_link_hash_indirect
|| ret->type == bfd_link_hash_warning)
ret = ret->u.i.link;
}
return ret;
}
/* Traverse a generic link hash table. The only reason this is not a
macro is to do better type checking. This code presumes that an
argument passed as a struct bfd_hash_entry * may be cause as a
struct bfd_link_hash_entry * with no explicit cast required on the
call. */
void
bfd_link_hash_traverse (table, func, info)
struct bfd_link_hash_table *table;
boolean (*func) PARAMS ((struct bfd_link_hash_entry *, PTR));
PTR info;
{
bfd_hash_traverse (&table->table,
((boolean (*) PARAMS ((struct bfd_hash_entry *, PTR)))
func),
info);
}
/* Add a symbol to the linker hash table undefs list. */
INLINE void
bfd_link_add_undef (table, h)
struct bfd_link_hash_table *table;
struct bfd_link_hash_entry *h;
{
BFD_ASSERT (h->next == NULL);
if (table->undefs_tail != (struct bfd_link_hash_entry *) NULL)
table->undefs_tail->next = h;
if (table->undefs == (struct bfd_link_hash_entry *) NULL)
table->undefs = h;
table->undefs_tail = h;
}
/* Routine to create an entry in an generic link hash table. */
static struct bfd_hash_entry *
generic_link_hash_newfunc (entry, table, string)
struct bfd_hash_entry *entry;
struct bfd_hash_table *table;
const char *string;
{
struct generic_link_hash_entry *ret =
(struct generic_link_hash_entry *) entry;
/* Allocate the structure if it has not already been allocated by a
subclass. */
if (ret == (struct generic_link_hash_entry *) NULL)
ret = ((struct generic_link_hash_entry *)
bfd_hash_allocate (table, sizeof (struct generic_link_hash_entry)));
/* Call the allocation method of the superclass. */
ret = ((struct generic_link_hash_entry *)
_bfd_link_hash_newfunc ((struct bfd_hash_entry *) ret,
table, string));
/* Set local fields. */
ret->sym = NULL;
return (struct bfd_hash_entry *) ret;
}
/* Create an generic link hash table. */
struct bfd_link_hash_table *
_bfd_generic_link_hash_table_create (abfd)
bfd *abfd;
{
struct generic_link_hash_table *ret;
ret = ((struct generic_link_hash_table *)
bfd_xmalloc (sizeof (struct generic_link_hash_table)));
if (! _bfd_link_hash_table_init (&ret->root, abfd,
generic_link_hash_newfunc))
{
free (ret);
return (struct bfd_link_hash_table *) NULL;
}
return &ret->root;
}
/* Generic function to add symbols from an object file to the global
hash table. */
boolean
_bfd_generic_link_add_symbols (abfd, info)
bfd *abfd;
struct bfd_link_info *info;
{
boolean ret;
switch (bfd_get_format (abfd))
{
case bfd_object:
ret = generic_link_add_object_symbols (abfd, info);
break;
case bfd_archive:
ret = _bfd_generic_link_add_archive_symbols
(abfd, info, generic_link_check_archive_element);
break;
default:
bfd_error = wrong_format;
ret = false;
}
/* If we might be using the C based alloca function, make sure we
have dumped the symbol tables we just allocated. */
#ifndef __GNUC__
#ifndef alloca
alloca (0);
#endif
#endif
return ret;
}
/* Add symbols from an object file to the global hash table. */
static boolean
generic_link_add_object_symbols (abfd, info)
bfd *abfd;
struct bfd_link_info *info;
{
size_t symsize;
asymbol **symbols;
bfd_size_type symbol_count;
symsize = get_symtab_upper_bound (abfd);
symbols = (asymbol **) alloca (symsize);
symbol_count = bfd_canonicalize_symtab (abfd, symbols);
return generic_link_add_symbol_list (abfd, info, symbol_count, symbols);
}
/* We build a hash table of all symbols defined in an archive. */
/* An archive symbol may be defined by multiple archive elements.
This linked list is used to hold the elements. */
struct archive_list
{
struct archive_list *next;
int indx;
};
/* An entry in an archive hash table. */
struct archive_hash_entry
{
struct bfd_hash_entry root;
/* Where the symbol is defined. */
struct archive_list *defs;
};
/* An archive hash table itself. */
struct archive_hash_table
{
struct bfd_hash_table table;
};
static struct bfd_hash_entry *archive_hash_newfunc
PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *));
static boolean archive_hash_table_init
PARAMS ((struct archive_hash_table *,
struct bfd_hash_entry *(*) (struct bfd_hash_entry *,
struct bfd_hash_table *,
const char *)));
/* Create a new entry for an archive hash table. */
static struct bfd_hash_entry *
archive_hash_newfunc (entry, table, string)
struct bfd_hash_entry *entry;
struct bfd_hash_table *table;
const char *string;
{
struct archive_hash_entry *ret = (struct archive_hash_entry *) entry;
/* Allocate the structure if it has not already been allocated by a
subclass. */
if (ret == (struct archive_hash_entry *) NULL)
ret = ((struct archive_hash_entry *)
bfd_hash_allocate (table, sizeof (struct archive_hash_entry)));
/* Call the allocation method of the superclass. */
ret = ((struct archive_hash_entry *)
bfd_hash_newfunc ((struct bfd_hash_entry *) ret, table, string));
/* Initialize the local fields. */
ret->defs = (struct archive_list *) NULL;
return (struct bfd_hash_entry *) ret;
}
/* Initialize an archive hash table. */
static boolean
archive_hash_table_init (table, newfunc)
struct archive_hash_table *table;
struct bfd_hash_entry *(*newfunc) PARAMS ((struct bfd_hash_entry *,
struct bfd_hash_table *,
const char *));
{
return bfd_hash_table_init (&table->table, newfunc);
}
/* Look up an entry in an archive hash table. */
#define archive_hash_lookup(t, string, create, copy) \
((struct archive_hash_entry *) \
bfd_hash_lookup (&(t)->table, (string), (create), (copy)))
/* Free an archive hash table. */
#define archive_hash_table_free(t) bfd_hash_table_free (&(t)->table)
/* Generic function to add symbols from an archive file to the global
hash file. This function presumes that the archive symbol table
has already been read in (this is normally done by the
bfd_check_format entry point). It looks through the undefined and
common symbols and searches the archive symbol table for them. If
it finds an entry, it includes the associated object file in the
link.
The old linker looked through the archive symbol table for
undefined symbols. We do it the other way around, looking through
undefined symbols for symbols defined in the archive. The
advantage of the newer scheme is that we only have to look through
the list of undefined symbols once, whereas the old method had to
re-search the symbol table each time a new object file was added.
The CHECKFN argument is used to see if an object file should be
included. CHECKFN should set *PNEEDED to true if the object file
should be included, and must also call the bfd_link_info
add_archive_element callback function and handle adding the symbols
to the global hash table. CHECKFN should only return false if some
sort of error occurs.
For some formats, such as a.out, it is possible to look through an
object file but not actually include it in the link. The
archive_pass field in a BFD is used to avoid checking the symbols
of an object files too many times. When an object is included in
the link, archive_pass is set to -1. If an object is scanned but
not included, archive_pass is set to the pass number. The pass
number is incremented each time a new object file is included. The
pass number is used because when a new object file is included it
may create new undefined symbols which cause a previously examined
object file to be included. */
boolean
_bfd_generic_link_add_archive_symbols (abfd, info, checkfn)
bfd *abfd;
struct bfd_link_info *info;
boolean (*checkfn) PARAMS ((bfd *, struct bfd_link_info *,
boolean *pneeded));
{
carsym *arsyms;
carsym *arsym_end;
register carsym *arsym;
int pass;
struct archive_hash_table arsym_hash;
int indx;
struct bfd_link_hash_entry **pundef;
if (! bfd_has_map (abfd))
{
bfd_error = no_symbols;
return false;
}
arsyms = bfd_ardata (abfd)->symdefs;
arsym_end = arsyms + bfd_ardata (abfd)->symdef_count;
/* In order to quickly determine whether an symbol is defined in
this archive, we build a hash table of the symbols. */
if (! archive_hash_table_init (&arsym_hash, archive_hash_newfunc))
return false;
for (arsym = arsyms, indx = 0; arsym < arsym_end; arsym++, indx++)
{
struct archive_hash_entry *arh;
struct archive_list *l;
arh = archive_hash_lookup (&arsym_hash, arsym->name, true, false);
if (arh == (struct archive_hash_entry *) NULL)
return false;
l = (struct archive_list *) alloca (sizeof (struct archive_list));
l->next = arh->defs;
arh->defs = l;
l->indx = indx;
}
pass = 1;
/* New undefined symbols are added to the end of the list, so we
only need to look through it once. */
pundef = &info->hash->undefs;
while (*pundef != (struct bfd_link_hash_entry *) NULL)
{
struct bfd_link_hash_entry *h;
struct archive_hash_entry *arh;
struct archive_list *l;
h = *pundef;
/* When a symbol is defined, it is not necessarily removed from
the list. */
if (h->type != bfd_link_hash_undefined
&& h->type != bfd_link_hash_common)
{
/* Remove this entry from the list, for general cleanliness
and because we are going to look through the list again
if we search any more libraries. We can't remove the
entry if it is the tail, because that would lose any
entries we add to the list later on. */
if (*pundef != info->hash->undefs_tail)
*pundef = (*pundef)->next;
else
pundef = &(*pundef)->next;
continue;
}
/* Look for this symbol in the archive symbol map. */
arh = archive_hash_lookup (&arsym_hash, h->root.string, false, false);
if (arh == (struct archive_hash_entry *) NULL)
{
pundef = &(*pundef)->next;
continue;
}
/* Look at all the objects which define this symbol. */
for (l = arh->defs; l != (struct archive_list *) NULL; l = l->next)
{
bfd *element;
boolean needed;
/* If the symbol has gotten defined along the way, quit. */
if (h->type != bfd_link_hash_undefined
&& h->type != bfd_link_hash_common)
break;
element = bfd_get_elt_at_index (abfd, l->indx);
if (element == (bfd *) NULL)
return false;
/* If we've already included this element, or if we've
already checked it on this pass, continue. */
if (element->archive_pass == -1
|| element->archive_pass == pass)
continue;
/* If we can't figure this element out, just ignore it. */
if (! bfd_check_format (element, bfd_object))
{
element->archive_pass = -1;
continue;
}
/* CHECKFN will see if this element should be included, and
go ahead and include it if appropriate. */
if (! (*checkfn) (element, info, &needed))
return false;
if (! needed)
element->archive_pass = pass;
else
{
element->archive_pass = -1;
/* Increment the pass count to show that we may need to
recheck object files which were already checked. */
++pass;
}
}
pundef = &(*pundef)->next;
}
archive_hash_table_free (&arsym_hash);
return true;
}
/* See if we should include an archive element. */
static boolean
generic_link_check_archive_element (abfd, info, pneeded)
bfd *abfd;
struct bfd_link_info *info;
boolean *pneeded;
{
size_t symsize;
asymbol **symbols;
bfd_size_type symbol_count;
asymbol **pp, **ppend;
*pneeded = false;
symsize = get_symtab_upper_bound (abfd);
symbols = (asymbol **) alloca (symsize);
symbol_count = bfd_canonicalize_symtab (abfd, symbols);
pp = symbols;
ppend = symbols + symbol_count;
for (; pp < ppend; pp++)
{
asymbol *p;
struct bfd_link_hash_entry *h;
p = *pp;
/* We are only interested in globally visible symbols. */
if (! bfd_is_com_section (p->section)
&& (p->flags & (BSF_GLOBAL | BSF_INDIRECT | BSF_WEAK)) == 0)
continue;
/* We are only interested if we know something about this
symbol, and it is undefined or common. An undefined weak
symbol (type bfd_link_hash_weak) is not considered to be a
reference when pulling files out of an archive. See the SVR4
ABI, p. 4-27. */
h = bfd_link_hash_lookup (info->hash, bfd_asymbol_name (p), false,
false, true);
if (h == (struct bfd_link_hash_entry *) NULL
|| (h->type != bfd_link_hash_undefined
&& h->type != bfd_link_hash_common))
continue;
/* P is a symbol we are looking for. */
if (! bfd_is_com_section (p->section))
{
/* This object file defines this symbol, so pull it in. */
if (! (*info->callbacks->add_archive_element) (info, abfd,
bfd_asymbol_name (p)))
return false;
if (! generic_link_add_symbol_list (abfd, info, symbol_count,
symbols))
return false;
*pneeded = true;
return true;
}
/* P is a common symbol. */
if (h->type == bfd_link_hash_undefined)
{
bfd *symbfd;
symbfd = h->u.undef.abfd;
if (symbfd == (bfd *) NULL)
{
/* This symbol was created as undefined from outside
BFD. We assume that we should link in the object
file. This is for the -u option in the linker. */
if (! (*info->callbacks->add_archive_element)
(info, abfd, bfd_asymbol_name (p)))
return false;
*pneeded = true;
return true;
}
/* Turn the symbol into a common symbol but do not link in
the object file. This is how a.out works. Object
formats that require different semantics must implement
this function differently. This symbol is already on the
undefs list. */
h->type = bfd_link_hash_common;
h->u.c.size = bfd_asymbol_value (p);
h->u.c.section = bfd_make_section_old_way (symbfd,
"COMMON");
}
else
{
/* Adjust the size of the common symbol if necessary. This
is how a.out works. Object formats that require
different semantics must implement this function
differently. */
if (bfd_asymbol_value (p) > h->u.c.size)
h->u.c.size = bfd_asymbol_value (p);
}
}
/* This archive element is not needed. */
return true;
}
/* Add the symbol from an object file to the global hash table. */
static boolean
generic_link_add_symbol_list (abfd, info, symbol_count, symbols)
bfd *abfd;
struct bfd_link_info *info;
bfd_size_type symbol_count;
asymbol **symbols;
{
asymbol **pp, **ppend;
pp = symbols;
ppend = symbols + symbol_count;
for (; pp < ppend; pp++)
{
asymbol *p;
p = *pp;
if ((p->flags & (BSF_INDIRECT
| BSF_WARNING
| BSF_GLOBAL
| BSF_CONSTRUCTOR
| BSF_WEAK)) != 0
|| bfd_get_section (p) == &bfd_und_section
|| bfd_is_com_section (bfd_get_section (p))
|| bfd_get_section (p) == &bfd_ind_section)
{
const char *name;
const char *string;
struct generic_link_hash_entry *h;
name = bfd_asymbol_name (p);
if ((p->flags & BSF_INDIRECT) != 0
|| p->section == &bfd_ind_section)
string = bfd_asymbol_name ((asymbol *) p->value);
else if ((p->flags & BSF_WARNING) != 0)
{
/* The name of P is actually the warning string, and the
value is actually a pointer to the symbol to warn
about. */
string = name;
name = bfd_asymbol_name ((asymbol *) p->value);
}
else
string = NULL;
if (! (_bfd_generic_link_add_one_symbol
(info, abfd, name, p->flags, bfd_get_section (p),
p->value, string, false,
(struct bfd_link_hash_entry **) &h)))
return false;
/* Save the BFD symbol so that we don't lose any backend
specific information that may be attached to it. We only
want this one if it gives more information than the
existing one; we don't want to replace a defined symbol
with an undefined one. This routine may be called with a
hash table other than the generic hash table, so we only
do this if we are certain that the hash table is a
generic one. */
if (info->hash->creator == abfd->xvec)
{
if (h->sym == (asymbol *) NULL
|| (bfd_get_section (p) != &bfd_und_section
&& (! bfd_is_com_section (bfd_get_section (p))
|| (bfd_get_section (h->sym) == &bfd_und_section))))
h->sym = p;
}
}
}
return true;
}
/* We use a state table to deal with adding symbols from an object
file. The first index into the state table describes the symbol
from the object file. The second index into the state table is the
type of the symbol in the hash table. */
/* The symbol from the object file is turned into one of these row
values. */
enum link_row
{
UNDEF_ROW, /* Undefined. */
UNDEFW_ROW, /* Weak undefined. */
DEF_ROW, /* Defined. */
DEFW_ROW, /* Weak defined. */
COMMON_ROW, /* Common. */
INDR_ROW, /* Indirect. */
WARN_ROW, /* Warning. */
SET_ROW /* Member of set. */
};
/* The actions to take in the state table. */
enum link_action
{
FAIL, /* Abort. */
UND, /* Mark symbol undefined. */
WEAK, /* Mark symbol weak undefined. */
DEF, /* Mark symbol defined. */
COM, /* Mark symbol common. */
CREF, /* Possibly warn about common reference to defined symbol. */
CDEF, /* Define existing common symbol. */
NOACT, /* No action. */
BIG, /* Mark symbol common using largest size. */
MDEF, /* Multiple definition error. */
IND, /* Make indirect symbol. */
SET, /* Add value to set. */
MWARN, /* Make warning symbol. */
WARN, /* Issue warning. */
CYCLE, /* Repeat with symbol pointed to. */
WARNC /* Issue warning and then CYCLE. */
};
/* The state table itself. The first index is a link_row and the
second index is a bfd_link_hash_type. */
static const enum link_action link_action[8][7] =
{
/* current\prev new undef weak def com indr warn */
/* UNDEF_ROW */ {UND, NOACT, NOACT, NOACT, NOACT, CYCLE, WARNC },
/* UNDEFW_ROW */ {WEAK, WEAK, NOACT, NOACT, NOACT, CYCLE, WARNC },
/* DEF_ROW */ {DEF, DEF, DEF, MDEF, CDEF, CYCLE, CYCLE },
/* DEFW_ROW */ {DEF, DEF, DEF, NOACT, NOACT, CYCLE, CYCLE },
/* COMMON_ROW */ {COM, COM, COM, CREF, BIG, CYCLE, WARNC },
/* INDR_ROW */ {IND, IND, IND, MDEF, MDEF, MDEF, WARNC },
/* WARN_ROW */ {MWARN, WARN, WARN, MWARN, MWARN, MWARN, NOACT },
/* SET_ROW */ {SET, SET, SET, SET, SET, CYCLE, WARNC }
};
/* Add a symbol to the global hash table.
ABFD is the BFD the symbol comes from.
NAME is the name of the symbol.
FLAGS is the BSF_* bits associated with the symbol.
SECTION is the section in which the symbol is defined; this may be
bfd_und_section or bfd_com_section.
VALUE is the value of the symbol, relative to the section.
STRING is used for either an indirect symbol, in which case it is
the name of the symbol to indirect to, or a warning symbol, in
which case it is the warning string.
COPY is true if NAME or STRING must be copied into locally
allocated memory if they need to be saved.
HASHP, if not NULL, is a place to store the created hash table
entry. */
boolean
_bfd_generic_link_add_one_symbol (info, abfd, name, flags, section, value,
string, copy, hashp)
struct bfd_link_info *info;
bfd *abfd;
const char *name;
flagword flags;
asection *section;
bfd_vma value;
const char *string;
boolean copy;
struct bfd_link_hash_entry **hashp;
{
enum link_row row;
struct bfd_link_hash_entry *h;
boolean cycle;
if (section == &bfd_ind_section
|| (flags & BSF_INDIRECT) != 0)
row = INDR_ROW;
else if ((flags & BSF_WARNING) != 0)
row = WARN_ROW;
else if ((flags & BSF_CONSTRUCTOR) != 0)
row = SET_ROW;
else if (section == &bfd_und_section)
{
if ((flags & BSF_WEAK) != 0)
row = UNDEFW_ROW;
else
row = UNDEF_ROW;
}
else if ((flags & BSF_WEAK) != 0)
row = DEFW_ROW;
else if (bfd_is_com_section (section))
row = COMMON_ROW;
else
row = DEF_ROW;
h = bfd_link_hash_lookup (info->hash, name, true, copy, false);
if (h == (struct bfd_link_hash_entry *) NULL)
{
if (hashp != (struct bfd_link_hash_entry **) NULL)
*hashp = NULL;
return false;
}
if (info->notice_hash != (struct bfd_hash_table *) NULL
&& (bfd_hash_lookup (info->notice_hash, name, false, false)
!= (struct bfd_hash_entry *) NULL))
{
if (! (*info->callbacks->notice) (info, name, abfd, section, value))
return false;
}
if (hashp != (struct bfd_link_hash_entry **) NULL)
*hashp = h;
do
{
enum link_action action;
cycle = false;
action = link_action[(int) row][(int) h->type];
switch (action)
{
case FAIL:
abort ();
case UND:
h->type = bfd_link_hash_undefined;
h->u.undef.abfd = abfd;
bfd_link_add_undef (info->hash, h);
break;
case WEAK:
h->type = bfd_link_hash_weak;
h->u.undef.abfd = abfd;
break;
case CDEF:
BFD_ASSERT (h->type == bfd_link_hash_common);
if (! ((*info->callbacks->multiple_common)
(info, name,
h->u.c.section->owner, bfd_link_hash_common, h->u.c.size,
abfd, bfd_link_hash_defined, (bfd_vma) 0)))
return false;
/* Fall through. */
case DEF:
h->type = bfd_link_hash_defined;
h->u.def.section = section;
h->u.def.value = value;
break;
case COM:
if (h->type == bfd_link_hash_new)
bfd_link_add_undef (info->hash, h);
h->type = bfd_link_hash_common;
h->u.c.size = value;
if (section == &bfd_com_section)
h->u.c.section = bfd_make_section_old_way (abfd, "COMMON");
else if (section->owner != abfd)
h->u.c.section = bfd_make_section_old_way (abfd, section->name);
else
h->u.c.section = section;
break;
case NOACT:
break;
case BIG:
BFD_ASSERT (h->type == bfd_link_hash_common);
if (! ((*info->callbacks->multiple_common)
(info, name,
h->u.c.section->owner, bfd_link_hash_common, h->u.c.size,
abfd, bfd_link_hash_common, value)))
return false;
if (value > h->u.c.size)
h->u.c.size = value;
if (h->u.c.section == (asection *) NULL)
h->u.c.section = bfd_make_section_old_way (abfd, "COMMON");
break;
case CREF:
BFD_ASSERT (h->type == bfd_link_hash_defined);
if (! ((*info->callbacks->multiple_common)
(info, name,
h->u.def.section->owner, bfd_link_hash_defined, (bfd_vma) 0,
abfd, bfd_link_hash_common, value)))
return false;
break;
case MDEF:
{
asection *msec;
bfd_vma mval;
switch (h->type)
{
case bfd_link_hash_defined:
msec = h->u.def.section;
mval = h->u.def.value;
break;
case bfd_link_hash_common:
msec = &bfd_com_section;
mval = h->u.c.size;
break;
case bfd_link_hash_indirect:
msec = &bfd_ind_section;
mval = 0;
break;
default:
abort ();
}
if (! ((*info->callbacks->multiple_definition)
(info, name, msec->owner, msec, mval, abfd, section,
value)))
return false;
}
break;
case IND:
{
struct bfd_link_hash_entry *inh;
/* STRING is the name of the symbol we want to indirect
to. */
inh = bfd_link_hash_lookup (info->hash, string, true, copy,
false);
if (inh == (struct bfd_link_hash_entry *) NULL)
return false;
if (inh->type == bfd_link_hash_new)
{
inh->type = bfd_link_hash_undefined;
inh->u.undef.abfd = abfd;
bfd_link_add_undef (info->hash, inh);
}
h->type = bfd_link_hash_indirect;
h->u.i.link = inh;
}
break;
case SET:
if (! (*info->callbacks->add_to_set) (info, h, abfd, section, value))
return false;
break;
case WARN:
case WARNC:
if (h->u.i.warning != NULL)
{
if (! (*info->callbacks->warning) (info, h->u.i.warning))
return false;
/* Only issue a warning once. */
h->u.i.warning = NULL;
}
if (action == WARN)
break;
/* Fall through. */
case CYCLE:
h = h->u.i.link;
cycle = true;
break;
case MWARN:
{
struct bfd_link_hash_entry *sub;
/* STRING is the warning to give. */
sub = ((struct bfd_link_hash_entry *)
bfd_hash_allocate (&info->hash->table,
sizeof (struct bfd_link_hash_entry)));
*sub = *h;
h->type = bfd_link_hash_warning;
h->u.i.link = sub;
if (! copy)
h->u.i.warning = string;
else
{
char *w;
w = bfd_hash_allocate (&info->hash->table,
strlen (string) + 1);
strcpy (w, string);
h->u.i.warning = w;
}
}
break;
}
}
while (cycle);
return true;
}
/* Generic final link routine. */
boolean
_bfd_generic_final_link (abfd, info)
bfd *abfd;
struct bfd_link_info *info;
{
bfd *sub;
asection *o;
struct bfd_link_order *p;
size_t outsymalloc;
struct generic_write_global_symbol_info wginfo;
abfd->outsymbols = (asymbol **) NULL;
abfd->symcount = 0;
outsymalloc = 0;
/* Build the output symbol table. This also reads in the symbols
for all the input BFDs, keeping them in the outsymbols field. */
for (sub = info->input_bfds; sub != (bfd *) NULL; sub = sub->link_next)
if (! _bfd_generic_link_output_symbols (abfd, sub, info, &outsymalloc))
return false;
/* Accumulate the global symbols. */
wginfo.output_bfd = abfd;
wginfo.psymalloc = &outsymalloc;
_bfd_generic_link_hash_traverse (_bfd_generic_hash_table (info),
_bfd_generic_link_write_global_symbol,
(PTR) &wginfo);
if (info->relocateable)
{
/* Allocate space for the output relocs for each section. */
for (o = abfd->sections;
o != (asection *) NULL;
o = o->next)
{
o->reloc_count = 0;
for (p = o->link_order_head;
p != (struct bfd_link_order *) NULL;
p = p->next)
{
if (p->type == bfd_indirect_link_order)
{
asection *input_section;
bfd *input_bfd;
bfd_size_type relsize;
arelent **relocs;
bfd_size_type reloc_count;
input_section = p->u.indirect.section;
input_bfd = input_section->owner;
relsize = bfd_get_reloc_upper_bound (input_bfd,
input_section);
relocs = (arelent **) bfd_xmalloc (relsize);
reloc_count =
bfd_canonicalize_reloc (input_bfd, input_section,
relocs,
bfd_get_outsymbols (input_bfd));
BFD_ASSERT (reloc_count == input_section->reloc_count);
o->reloc_count += reloc_count;
free (relocs);
}
}
if (o->reloc_count > 0)
{
o->orelocation = ((arelent **)
bfd_alloc (abfd,
(o->reloc_count
* sizeof (arelent *))));
/* Reset the count so that it can be used as an index
when putting in the output relocs. */
o->reloc_count = 0;
}
}
}
/* Handle all the link order information for the sections. */
for (o = abfd->sections;
o != (asection *) NULL;
o = o->next)
{
for (p = o->link_order_head;
p != (struct bfd_link_order *) NULL;
p = p->next)
{
switch (p->type)
{
case bfd_indirect_link_order:
if (! _bfd_generic_indirect_link_order (abfd, info, o, p))
return false;
break;
default:
if (! _bfd_default_link_order (abfd, info, o, p))
return false;
break;
}
}
}
return true;
}
/* Add an output symbol to the output BFD. */
static boolean
generic_add_output_symbol (output_bfd, psymalloc, sym)
bfd *output_bfd;
size_t *psymalloc;
asymbol *sym;
{
if (output_bfd->symcount >= *psymalloc)
{
asymbol **newsyms;
if (*psymalloc == 0)
*psymalloc = 124;
else
*psymalloc *= 2;
if (output_bfd->outsymbols == (asymbol **) NULL)
newsyms = (asymbol **) malloc (*psymalloc * sizeof (asymbol *));
else
newsyms = (asymbol **) realloc (output_bfd->outsymbols,
*psymalloc * sizeof (asymbol *));
if (newsyms == (asymbol **) NULL)
{
bfd_error = no_memory;
return false;
}
output_bfd->outsymbols = newsyms;
}
output_bfd->outsymbols[output_bfd->symcount] = sym;
++output_bfd->symcount;
return true;
}
/* Handle the symbols for an input BFD. */
boolean
_bfd_generic_link_output_symbols (output_bfd, input_bfd, info, psymalloc)
bfd *output_bfd;
bfd *input_bfd;
struct bfd_link_info *info;
size_t *psymalloc;
{
size_t symsize;
asymbol **sym_ptr;
asymbol **sym_end;
symsize = get_symtab_upper_bound (input_bfd);
input_bfd->outsymbols = (asymbol **) bfd_alloc (input_bfd, symsize);
input_bfd->symcount = bfd_canonicalize_symtab (input_bfd,
input_bfd->outsymbols);
/* Create a filename symbol if we are supposed to. */
if (info->create_object_symbols_section != (asection *) NULL)
{
asection *sec;
for (sec = input_bfd->sections;
sec != (asection *) NULL;
sec = sec->next)
{
if (sec->output_section == info->create_object_symbols_section)
{
asymbol *newsym;
newsym = bfd_make_empty_symbol (input_bfd);
newsym->name = input_bfd->filename;
newsym->value = 0;
newsym->flags = BSF_LOCAL | BSF_FILE;
newsym->section = sec;
if (! generic_add_output_symbol (output_bfd, psymalloc,
newsym))
return false;
break;
}
}
}
/* Adjust the values of the globally visible symbols, and write out
local symbols. */
sym_ptr = bfd_get_outsymbols (input_bfd);
sym_end = sym_ptr + bfd_get_symcount (input_bfd);
for (; sym_ptr < sym_end; sym_ptr++)
{
asymbol *sym;
struct generic_link_hash_entry *h;
boolean output;
h = (struct generic_link_hash_entry *) NULL;
sym = *sym_ptr;
if ((sym->flags & (BSF_INDIRECT
| BSF_WARNING
| BSF_GLOBAL
| BSF_CONSTRUCTOR
| BSF_WEAK)) != 0
|| bfd_get_section (sym) == &bfd_und_section
|| bfd_is_com_section (bfd_get_section (sym))
|| bfd_get_section (sym) == &bfd_ind_section)
{
h = _bfd_generic_link_hash_lookup (_bfd_generic_hash_table (info),
bfd_asymbol_name (sym),
false, false, true);
if (h != (struct generic_link_hash_entry *) NULL)
{
/* Force all references to this symbol to point to
the same area in memory. It is possible that
this routine will be called with a hash table
other than a generic hash table, so we double
check that. */
if (info->hash->creator == input_bfd->xvec)
{
if (h->sym != (asymbol *) NULL)
*sym_ptr = sym = h->sym;
}
switch (h->root.type)
{
default:
case bfd_link_hash_new:
abort ();
case bfd_link_hash_undefined:
case bfd_link_hash_weak:
break;
case bfd_link_hash_defined:
sym->value = h->root.u.def.value;
sym->section = h->root.u.def.section;
sym->flags |= BSF_GLOBAL;
break;
case bfd_link_hash_common:
sym->value = h->root.u.c.size;
sym->flags |= BSF_GLOBAL;
/* We do not set the section of the symbol to
c.section. c.section is saved so that we know
where to allocate the symbol if we define it. In
this case the type is still bfd_link_hash_common,
so we did not define it, so we do not want to use
that section. */
BFD_ASSERT (bfd_is_com_section (sym->section));
break;
}
}
}
/* This switch is straight from the old code in
write_file_locals in ldsym.c. */
if (info->strip == strip_some
&& (bfd_hash_lookup (info->keep_hash, bfd_asymbol_name (sym),
false, false)
== (struct bfd_hash_entry *) NULL))
output = false;
else if ((sym->flags & (BSF_GLOBAL | BSF_WEAK)) != 0)
{
/* If this symbol is marked as occurring now, rather
than at the end, output it now. This is used for
COFF C_EXT FCN symbols. FIXME: There must be a
better way. */
if (bfd_asymbol_bfd (sym) == input_bfd
&& (sym->flags & BSF_NOT_AT_END) != 0)
output = true;
else
output = false;
}
else if (sym->section == &bfd_ind_section)
output = false;
else if ((sym->flags & BSF_DEBUGGING) != 0)
{
if (info->strip == strip_none)
output = true;
else
output = false;
}
else if (sym->section == &bfd_und_section
|| bfd_is_com_section (sym->section))
output = false;
else if ((sym->flags & BSF_LOCAL) != 0)
{
if ((sym->flags & BSF_WARNING) != 0)
output = false;
else
{
switch (info->discard)
{
default:
case discard_all:
output = false;
break;
case discard_l:
if (bfd_asymbol_name (sym)[0] == info->lprefix[0]
&& (info->lprefix_len == 1
|| strncmp (bfd_asymbol_name (sym), info->lprefix,
info->lprefix_len) == 0))
output = false;
else
output = true;
break;
case discard_none:
output = true;
break;
}
}
}
else if ((sym->flags & BSF_CONSTRUCTOR))
{
if (info->strip != strip_all)
output = true;
else
output = false;
}
else
abort ();
if (output)
{
if (! generic_add_output_symbol (output_bfd, psymalloc, sym))
return false;
if (h != (struct generic_link_hash_entry *) NULL)
h->root.written = true;
}
}
return true;
}
/* Write out a global symbol, if it hasn't already been written out.
This is called for each symbol in the hash table. */
boolean
_bfd_generic_link_write_global_symbol (h, data)
struct generic_link_hash_entry *h;
PTR data;
{
struct generic_write_global_symbol_info *wginfo =
(struct generic_write_global_symbol_info *) data;
asymbol *sym;
if (h->root.written)
return true;
if (h->sym != (asymbol *) NULL)
{
sym = h->sym;
BFD_ASSERT (strcmp (bfd_asymbol_name (sym), h->root.root.string) == 0);
}
else
{
sym = bfd_make_empty_symbol (wginfo->output_bfd);
sym->name = h->root.root.string;
sym->flags = 0;
}
switch (h->root.type)
{
default:
case bfd_link_hash_new:
abort ();
case bfd_link_hash_undefined:
sym->section = &bfd_und_section;
sym->value = 0;
break;
case bfd_link_hash_weak:
sym->section = &bfd_und_section;
sym->value = 0;
sym->flags |= BSF_WEAK;
case bfd_link_hash_defined:
sym->section = h->root.u.def.section;
sym->value = h->root.u.def.value;
break;
case bfd_link_hash_common:
sym->value = h->root.u.c.size;
/* Do not set the section; see _bfd_generic_link_output_symbols. */
BFD_ASSERT (bfd_is_com_section (sym->section));
break;
case bfd_link_hash_indirect:
case bfd_link_hash_warning:
/* FIXME: What should we do here? */
break;
}
sym->flags |= BSF_GLOBAL;
if (! generic_add_output_symbol (wginfo->output_bfd, wginfo->psymalloc,
sym))
{
/* FIXME: No way to return failure. */
abort ();
}
h->root.written = true;
return true;
}
/* Handle an indirect section when doing a generic link. */
boolean
_bfd_generic_indirect_link_order (output_bfd, info, output_section, link_order)
bfd *output_bfd;
struct bfd_link_info *info;
asection *output_section;
struct bfd_link_order *link_order;
{
asection *input_section;
bfd *input_bfd;
bfd_byte *contents;
BFD_ASSERT ((output_section->flags & SEC_HAS_CONTENTS) != 0);
if (link_order->size == 0)
return true;
input_section = link_order->u.indirect.section;
input_bfd = input_section->owner;
BFD_ASSERT (input_section->output_section == output_section);
BFD_ASSERT (input_section->output_offset == link_order->offset);
BFD_ASSERT (bfd_section_size (input_bfd, input_section) == link_order->size);
/* Get and relocate the section contents. */
contents = (bfd_byte *) alloca (bfd_section_size (input_bfd, input_section));
contents = (bfd_get_relocated_section_contents
(output_bfd, info, link_order, contents, info->relocateable,
bfd_get_outsymbols (input_bfd)));
/* Output the section contents. */
if (! bfd_set_section_contents (output_bfd, output_section, contents,
link_order->offset, link_order->size))
return false;
return true;
}
/* Allocate a new link_order for a section. */
struct bfd_link_order *
bfd_new_link_order (abfd, section)
bfd *abfd;
asection *section;
{
struct bfd_link_order *new;
new = ((struct bfd_link_order *)
bfd_alloc_by_size_t (abfd, sizeof (struct bfd_link_order)));
new->type = bfd_undefined_link_order;
new->offset = 0;
new->size = 0;
new->next = (struct bfd_link_order *) NULL;
if (section->link_order_tail != (struct bfd_link_order *) NULL)
section->link_order_tail->next = new;
else
section->link_order_head = new;
section->link_order_tail = new;
return new;
}
/* Default link order processing routine. */
boolean
_bfd_default_link_order (abfd, info, sec, link_order)
bfd *abfd;
struct bfd_link_info *info;
asection *sec;
struct bfd_link_order *link_order;
{
switch (link_order->type)
{
case bfd_undefined_link_order:
default:
abort ();
case bfd_indirect_link_order:
abort ();
case bfd_fill_link_order:
return default_fill_link_order (abfd, info, sec, link_order);
}
}
/* Default routine to handle a bfd_fill_link_order. */
static boolean
default_fill_link_order (abfd, info, sec, link_order)
bfd *abfd;
struct bfd_link_info *info;
asection *sec;
struct bfd_link_order *link_order;
{
size_t size;
char *space;
size_t i;
int fill;
BFD_ASSERT ((sec->flags & SEC_HAS_CONTENTS) != 0);
size = (size_t) link_order->size;
space = (char *) alloca (size);
fill = link_order->u.fill.value;
for (i = 0; i < size; i += 2)
space[i] = fill >> 8;
for (i = 1; i < size; i += 2)
space[i] = fill;
return bfd_set_section_contents (abfd, sec, space,
(file_ptr) link_order->offset,
link_order->size);
}