| 1 | /* BFD back-end for linux flavored i386 a.out binaries.
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| 2 | Copyright 1992, 1993, 1994, 1995, 1996, 1997, 2001, 2002, 2003
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| 3 | Free Software Foundation, Inc.
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| 4 |
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| 5 | This file is part of BFD, the Binary File Descriptor library.
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| 6 |
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| 7 | This program is free software; you can redistribute it and/or modify
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| 8 | it under the terms of the GNU General Public License as published by
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| 9 | the Free Software Foundation; either version 2 of the License, or
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| 10 | (at your option) any later version.
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| 11 |
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| 12 | This program is distributed in the hope that it will be useful,
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| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of
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| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 15 | GNU General Public License for more details.
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| 16 |
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| 17 | You should have received a copy of the GNU General Public License
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| 18 | along with this program; if not, write to the Free Software
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| 19 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
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| 20 |
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| 21 | #define TARGET_PAGE_SIZE 4096
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| 22 | #define ZMAGIC_DISK_BLOCK_SIZE 1024
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| 23 | #define SEGMENT_SIZE TARGET_PAGE_SIZE
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| 24 | #define TEXT_START_ADDR 0x0
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| 25 | #define N_SHARED_LIB(x) 0
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| 26 |
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| 27 | #define MACHTYPE_OK(mtype) ((mtype) == M_386 || (mtype) == M_UNKNOWN)
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| 28 |
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| 29 | #include "bfd.h"
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| 30 | #include "sysdep.h"
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| 31 | #include "libbfd.h"
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| 32 | #include "aout/aout64.h"
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| 33 | #include "aout/stab_gnu.h"
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| 34 | #include "aout/ar.h"
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| 35 | #include "libaout.h" /* BFD a.out internal data structures */
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| 36 |
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| 37 | #define DEFAULT_ARCH bfd_arch_i386
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| 38 |
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| 39 | /* Do not "beautify" the CONCAT* macro args. Traditional C will not
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| 40 | remove whitespace added here, and thus will fail to concatenate
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| 41 | the tokens. */
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| 42 | #define MY(OP) CONCAT2 (i386linux_,OP)
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| 43 | #define TARGETNAME "a.out-i386-linux"
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| 44 |
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| 45 | extern const bfd_target MY(vec);
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| 46 |
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| 47 | /* We always generate QMAGIC files in preference to ZMAGIC files. It
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| 48 | would be possible to make this a linker option, if that ever
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| 49 | becomes important. */
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| 50 |
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| 51 | static void MY_final_link_callback
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| 52 | PARAMS ((bfd *, file_ptr *, file_ptr *, file_ptr *));
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| 53 | static bfd_boolean i386linux_bfd_final_link
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| 54 | PARAMS ((bfd *, struct bfd_link_info *));
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| 55 | static bfd_boolean i386linux_write_object_contents PARAMS ((bfd *));
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| 56 |
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| 57 | static bfd_boolean
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| 58 | i386linux_bfd_final_link (abfd, info)
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| 59 | bfd *abfd;
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| 60 | struct bfd_link_info *info;
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| 61 | {
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| 62 | obj_aout_subformat (abfd) = q_magic_format;
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| 63 | return NAME(aout,final_link) (abfd, info, MY_final_link_callback);
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| 64 | }
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| 65 |
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| 66 | #define MY_bfd_final_link i386linux_bfd_final_link
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| 67 |
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| 68 | /* Set the machine type correctly. */
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| 69 |
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| 70 | static bfd_boolean
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| 71 | i386linux_write_object_contents (abfd)
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| 72 | bfd *abfd;
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| 73 | {
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| 74 | struct external_exec exec_bytes;
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| 75 | struct internal_exec *execp = exec_hdr (abfd);
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| 76 |
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| 77 | N_SET_MACHTYPE (*execp, M_386);
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| 78 |
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| 79 | obj_reloc_entry_size (abfd) = RELOC_STD_SIZE;
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| 80 |
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| 81 | WRITE_HEADERS(abfd, execp);
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| 82 |
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| 83 | return TRUE;
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| 84 | }
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| 85 |
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| 86 | #define MY_write_object_contents i386linux_write_object_contents
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| 87 | |
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| 88 |
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| 89 | /* Code to link against Linux a.out shared libraries. */
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| 90 |
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| 91 | /* See if a symbol name is a reference to the global offset table. */
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| 92 |
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| 93 | #ifndef GOT_REF_PREFIX
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| 94 | #define GOT_REF_PREFIX "__GOT_"
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| 95 | #endif
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| 96 |
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| 97 | #define IS_GOT_SYM(name) \
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| 98 | (strncmp (name, GOT_REF_PREFIX, sizeof GOT_REF_PREFIX - 1) == 0)
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| 99 |
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| 100 | /* See if a symbol name is a reference to the procedure linkage table. */
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| 101 |
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| 102 | #ifndef PLT_REF_PREFIX
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| 103 | #define PLT_REF_PREFIX "__PLT_"
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| 104 | #endif
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| 105 |
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| 106 | #define IS_PLT_SYM(name) \
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| 107 | (strncmp (name, PLT_REF_PREFIX, sizeof PLT_REF_PREFIX - 1) == 0)
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| 108 |
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| 109 | /* This string is used to generate specialized error messages. */
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| 110 |
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| 111 | #ifndef NEEDS_SHRLIB
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| 112 | #define NEEDS_SHRLIB "__NEEDS_SHRLIB_"
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| 113 | #endif
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| 114 |
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| 115 | /* This special symbol is a set vector that contains a list of
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| 116 | pointers to fixup tables. It will be present in any dynamicly
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| 117 | linked file. The linker generated fixup table should also be added
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| 118 | to the list, and it should always appear in the second slot (the
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| 119 | first one is a dummy with a magic number that is defined in
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| 120 | crt0.o). */
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| 121 |
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| 122 | #ifndef SHARABLE_CONFLICTS
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| 123 | #define SHARABLE_CONFLICTS "__SHARABLE_CONFLICTS__"
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| 124 | #endif
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| 125 |
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| 126 | /* We keep a list of fixups. The terminology is a bit strange, but
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| 127 | each fixup contains two 32 bit numbers. A regular fixup contains
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| 128 | an address and a pointer, and at runtime we should store the
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| 129 | address at the location pointed to by the pointer. A builtin fixup
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| 130 | contains two pointers, and we should read the address using one
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| 131 | pointer and store it at the location pointed to by the other
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| 132 | pointer. Builtin fixups come into play when we have duplicate
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| 133 | __GOT__ symbols for the same variable. The builtin fixup will copy
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| 134 | the GOT pointer from one over into the other. */
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| 135 |
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| 136 | struct fixup
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| 137 | {
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| 138 | struct fixup *next;
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| 139 | struct linux_link_hash_entry *h;
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| 140 | bfd_vma value;
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| 141 |
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| 142 | /* Nonzero if this is a jump instruction that needs to be fixed,
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| 143 | zero if this is just a pointer */
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| 144 | char jump;
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| 145 |
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| 146 | char builtin;
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| 147 | };
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| 148 |
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| 149 | /* We don't need a special hash table entry structure, but we do need
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| 150 | to keep some information between linker passes, so we use a special
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| 151 | hash table. */
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| 152 |
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| 153 | struct linux_link_hash_entry
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| 154 | {
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| 155 | struct aout_link_hash_entry root;
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| 156 | };
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| 157 |
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| 158 | struct linux_link_hash_table
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| 159 | {
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| 160 | struct aout_link_hash_table root;
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| 161 |
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| 162 | /* First dynamic object found in link. */
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| 163 | bfd *dynobj;
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| 164 |
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| 165 | /* Number of fixups. */
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| 166 | size_t fixup_count;
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| 167 |
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| 168 | /* Number of builtin fixups. */
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| 169 | size_t local_builtins;
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| 170 |
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| 171 | /* List of fixups. */
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| 172 | struct fixup *fixup_list;
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| 173 | };
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| 174 |
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| 175 | static struct bfd_hash_entry *linux_link_hash_newfunc
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| 176 | PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *));
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| 177 | static struct bfd_link_hash_table *linux_link_hash_table_create
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| 178 | PARAMS ((bfd *));
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| 179 | static struct fixup *new_fixup
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| 180 | PARAMS ((struct bfd_link_info *, struct linux_link_hash_entry *,
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| 181 | bfd_vma, int));
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| 182 | static bfd_boolean linux_link_create_dynamic_sections
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| 183 | PARAMS ((bfd *, struct bfd_link_info *));
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| 184 | static bfd_boolean linux_add_one_symbol
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| 185 | PARAMS ((struct bfd_link_info *, bfd *, const char *, flagword, asection *,
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| 186 | bfd_vma, const char *, bfd_boolean, bfd_boolean,
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| 187 | struct bfd_link_hash_entry **));
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| 188 | static bfd_boolean linux_tally_symbols
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| 189 | PARAMS ((struct linux_link_hash_entry *, PTR));
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| 190 | static bfd_boolean linux_finish_dynamic_link
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| 191 | PARAMS ((bfd *, struct bfd_link_info *));
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| 192 |
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| 193 | /* Routine to create an entry in an Linux link hash table. */
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| 194 |
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| 195 | static struct bfd_hash_entry *
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| 196 | linux_link_hash_newfunc (entry, table, string)
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| 197 | struct bfd_hash_entry *entry;
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| 198 | struct bfd_hash_table *table;
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| 199 | const char *string;
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| 200 | {
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| 201 | struct linux_link_hash_entry *ret = (struct linux_link_hash_entry *) entry;
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| 202 |
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| 203 | /* Allocate the structure if it has not already been allocated by a
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| 204 | subclass. */
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| 205 | if (ret == (struct linux_link_hash_entry *) NULL)
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| 206 | ret = ((struct linux_link_hash_entry *)
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| 207 | bfd_hash_allocate (table, sizeof (struct linux_link_hash_entry)));
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| 208 | if (ret == NULL)
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| 209 | return (struct bfd_hash_entry *) ret;
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| 210 |
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| 211 | /* Call the allocation method of the superclass. */
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| 212 | ret = ((struct linux_link_hash_entry *)
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| 213 | NAME(aout,link_hash_newfunc) ((struct bfd_hash_entry *) ret,
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| 214 | table, string));
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| 215 | if (ret != NULL)
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| 216 | {
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| 217 | /* Set local fields; there aren't any. */
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| 218 | }
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| 219 |
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| 220 | return (struct bfd_hash_entry *) ret;
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| 221 | }
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| 222 |
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| 223 | /* Create a Linux link hash table. */
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| 224 |
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| 225 | static struct bfd_link_hash_table *
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| 226 | linux_link_hash_table_create (abfd)
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| 227 | bfd *abfd;
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| 228 | {
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| 229 | struct linux_link_hash_table *ret;
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| 230 | bfd_size_type amt = sizeof (struct linux_link_hash_table);
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| 231 |
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| 232 | ret = (struct linux_link_hash_table *) bfd_alloc (abfd, amt);
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| 233 | if (ret == (struct linux_link_hash_table *) NULL)
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| 234 | return (struct bfd_link_hash_table *) NULL;
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| 235 | if (! NAME(aout,link_hash_table_init) (&ret->root, abfd,
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| 236 | linux_link_hash_newfunc))
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| 237 | {
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| 238 | free (ret);
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| 239 | return (struct bfd_link_hash_table *) NULL;
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| 240 | }
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| 241 |
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| 242 | ret->dynobj = NULL;
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| 243 | ret->fixup_count = 0;
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| 244 | ret->local_builtins = 0;
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| 245 | ret->fixup_list = NULL;
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| 246 |
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| 247 | return &ret->root.root;
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| 248 | }
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| 249 |
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| 250 | /* Look up an entry in a Linux link hash table. */
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| 251 |
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| 252 | #define linux_link_hash_lookup(table, string, create, copy, follow) \
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| 253 | ((struct linux_link_hash_entry *) \
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| 254 | aout_link_hash_lookup (&(table)->root, (string), (create), (copy),\
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| 255 | (follow)))
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| 256 |
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| 257 | /* Traverse a Linux link hash table. */
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| 258 |
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| 259 | #define linux_link_hash_traverse(table, func, info) \
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| 260 | (aout_link_hash_traverse \
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| 261 | (&(table)->root, \
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| 262 | (bfd_boolean (*) PARAMS ((struct aout_link_hash_entry *, PTR))) (func), \
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| 263 | (info)))
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| 264 |
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| 265 | /* Get the Linux link hash table from the info structure. This is
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| 266 | just a cast. */
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| 267 |
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| 268 | #define linux_hash_table(p) ((struct linux_link_hash_table *) ((p)->hash))
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| 269 |
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| 270 | /* Store the information for a new fixup. */
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| 271 |
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| 272 | static struct fixup *
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| 273 | new_fixup (info, h, value, builtin)
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| 274 | struct bfd_link_info *info;
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| 275 | struct linux_link_hash_entry *h;
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| 276 | bfd_vma value;
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| 277 | int builtin;
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| 278 | {
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| 279 | struct fixup *f;
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| 280 |
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| 281 | f = (struct fixup *) bfd_hash_allocate (&info->hash->table,
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| 282 | sizeof (struct fixup));
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| 283 | if (f == NULL)
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| 284 | return f;
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| 285 | f->next = linux_hash_table (info)->fixup_list;
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| 286 | linux_hash_table (info)->fixup_list = f;
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| 287 | f->h = h;
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| 288 | f->value = value;
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| 289 | f->builtin = builtin;
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| 290 | f->jump = 0;
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| 291 | ++linux_hash_table (info)->fixup_count;
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| 292 | return f;
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| 293 | }
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| 294 |
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| 295 | /* We come here once we realize that we are going to link to a shared
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| 296 | library. We need to create a special section that contains the
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| 297 | fixup table, and we ultimately need to add a pointer to this into
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| 298 | the set vector for SHARABLE_CONFLICTS. At this point we do not
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| 299 | know the size of the section, but that's OK - we just need to
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| 300 | create it for now. */
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| 301 |
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| 302 | static bfd_boolean
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| 303 | linux_link_create_dynamic_sections (abfd, info)
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| 304 | bfd *abfd;
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| 305 | struct bfd_link_info *info ATTRIBUTE_UNUSED;
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| 306 | {
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| 307 | flagword flags;
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| 308 | register asection *s;
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| 309 |
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| 310 | /* Note that we set the SEC_IN_MEMORY flag. */
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| 311 | flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY;
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| 312 |
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| 313 | /* We choose to use the name ".linux-dynamic" for the fixup table.
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| 314 | Why not? */
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| 315 | s = bfd_make_section (abfd, ".linux-dynamic");
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| 316 | if (s == NULL
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| 317 | || ! bfd_set_section_flags (abfd, s, flags)
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| 318 | || ! bfd_set_section_alignment (abfd, s, 2))
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| 319 | return FALSE;
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| 320 | s->_raw_size = 0;
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| 321 | s->contents = 0;
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| 322 |
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| 323 | return TRUE;
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| 324 | }
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| 325 |
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| 326 | /* Function to add a single symbol to the linker hash table. This is
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| 327 | a wrapper around _bfd_generic_link_add_one_symbol which handles the
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| 328 | tweaking needed for dynamic linking support. */
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| 329 |
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| 330 | static bfd_boolean
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| 331 | linux_add_one_symbol (info, abfd, name, flags, section, value, string,
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| 332 | copy, collect, hashp)
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| 333 | struct bfd_link_info *info;
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| 334 | bfd *abfd;
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| 335 | const char *name;
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| 336 | flagword flags;
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| 337 | asection *section;
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| 338 | bfd_vma value;
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| 339 | const char *string;
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| 340 | bfd_boolean copy;
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| 341 | bfd_boolean collect;
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| 342 | struct bfd_link_hash_entry **hashp;
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| 343 | {
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| 344 | struct linux_link_hash_entry *h;
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| 345 | bfd_boolean insert;
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| 346 |
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| 347 | /* Look up and see if we already have this symbol in the hash table.
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| 348 | If we do, and the defining entry is from a shared library, we
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| 349 | need to create the dynamic sections.
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| 350 |
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| 351 | FIXME: What if abfd->xvec != info->hash->creator? We may want to
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| 352 | be able to link Linux a.out and ELF objects together, but serious
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| 353 | confusion is possible. */
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| 354 |
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| 355 | insert = FALSE;
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| 356 |
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| 357 | if (! info->relocateable
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| 358 | && linux_hash_table (info)->dynobj == NULL
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| 359 | && strcmp (name, SHARABLE_CONFLICTS) == 0
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| 360 | && (flags & BSF_CONSTRUCTOR) != 0
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| 361 | && abfd->xvec == info->hash->creator)
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| 362 | {
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| 363 | if (! linux_link_create_dynamic_sections (abfd, info))
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| 364 | return FALSE;
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| 365 | linux_hash_table (info)->dynobj = abfd;
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| 366 | insert = TRUE;
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| 367 | }
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| 368 |
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| 369 | if (bfd_is_abs_section (section)
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| 370 | && abfd->xvec == info->hash->creator)
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| 371 | {
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| 372 | h = linux_link_hash_lookup (linux_hash_table (info), name, FALSE,
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| 373 | FALSE, FALSE);
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| 374 | if (h != NULL
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| 375 | && (h->root.root.type == bfd_link_hash_defined
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| 376 | || h->root.root.type == bfd_link_hash_defweak))
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| 377 | {
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| 378 | struct fixup *f;
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| 379 |
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| 380 | if (hashp != NULL)
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| 381 | *hashp = (struct bfd_link_hash_entry *) h;
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| 382 |
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| 383 | f = new_fixup (info, h, value, ! IS_PLT_SYM (name));
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| 384 | if (f == NULL)
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| 385 | return FALSE;
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| 386 | f->jump = IS_PLT_SYM (name);
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| 387 |
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| 388 | return TRUE;
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| 389 | }
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| 390 | }
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| 391 |
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| 392 | /* Do the usual procedure for adding a symbol. */
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| 393 | if (! _bfd_generic_link_add_one_symbol (info, abfd, name, flags, section,
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| 394 | value, string, copy, collect,
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| 395 | hashp))
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| 396 | return FALSE;
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| 397 |
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| 398 | /* Insert a pointer to our table in the set vector. The dynamic
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| 399 | linker requires this information */
|
|---|
| 400 | if (insert)
|
|---|
| 401 | {
|
|---|
| 402 | asection *s;
|
|---|
| 403 |
|
|---|
| 404 | /* Here we do our special thing to add the pointer to the
|
|---|
| 405 | dynamic section in the SHARABLE_CONFLICTS set vector. */
|
|---|
| 406 | s = bfd_get_section_by_name (linux_hash_table (info)->dynobj,
|
|---|
| 407 | ".linux-dynamic");
|
|---|
| 408 | BFD_ASSERT (s != NULL);
|
|---|
| 409 |
|
|---|
| 410 | if (! (_bfd_generic_link_add_one_symbol
|
|---|
| 411 | (info, linux_hash_table (info)->dynobj, SHARABLE_CONFLICTS,
|
|---|
| 412 | BSF_GLOBAL | BSF_CONSTRUCTOR, s, (bfd_vma) 0, NULL,
|
|---|
| 413 | FALSE, FALSE, NULL)))
|
|---|
| 414 | return FALSE;
|
|---|
| 415 | }
|
|---|
| 416 |
|
|---|
| 417 | return TRUE;
|
|---|
| 418 | }
|
|---|
| 419 |
|
|---|
| 420 | /* We will crawl the hash table and come here for every global symbol.
|
|---|
| 421 | We will examine each entry and see if there are indications that we
|
|---|
| 422 | need to add a fixup. There are two possible cases - one is where
|
|---|
| 423 | you have duplicate definitions of PLT or GOT symbols - these will
|
|---|
| 424 | have already been caught and added as "builtin" fixups. If we find
|
|---|
| 425 | that the corresponding non PLT/GOT symbol is also present, we
|
|---|
| 426 | convert it to a regular fixup instead.
|
|---|
| 427 |
|
|---|
| 428 | This function is called via linux_link_hash_traverse. */
|
|---|
| 429 |
|
|---|
| 430 | static bfd_boolean
|
|---|
| 431 | linux_tally_symbols (h, data)
|
|---|
| 432 | struct linux_link_hash_entry *h;
|
|---|
| 433 | PTR data;
|
|---|
| 434 | {
|
|---|
| 435 | struct bfd_link_info *info = (struct bfd_link_info *) data;
|
|---|
| 436 | struct fixup *f, *f1;
|
|---|
| 437 | int is_plt;
|
|---|
| 438 | struct linux_link_hash_entry *h1, *h2;
|
|---|
| 439 | bfd_boolean exists;
|
|---|
| 440 |
|
|---|
| 441 | if (h->root.root.type == bfd_link_hash_warning)
|
|---|
| 442 | h = (struct linux_link_hash_entry *) h->root.root.u.i.link;
|
|---|
| 443 |
|
|---|
| 444 | if (h->root.root.type == bfd_link_hash_undefined
|
|---|
| 445 | && strncmp (h->root.root.root.string, NEEDS_SHRLIB,
|
|---|
| 446 | sizeof NEEDS_SHRLIB - 1) == 0)
|
|---|
| 447 | {
|
|---|
| 448 | const char *name;
|
|---|
| 449 | char *p;
|
|---|
| 450 | char *alloc = NULL;
|
|---|
| 451 |
|
|---|
| 452 | name = h->root.root.root.string + sizeof NEEDS_SHRLIB - 1;
|
|---|
| 453 | p = strrchr (name, '_');
|
|---|
| 454 | if (p != NULL)
|
|---|
| 455 | alloc = (char *) bfd_malloc ((bfd_size_type) strlen (name) + 1);
|
|---|
| 456 |
|
|---|
| 457 | if (p == NULL || alloc == NULL)
|
|---|
| 458 | (*_bfd_error_handler) (_("Output file requires shared library `%s'\n"),
|
|---|
| 459 | name);
|
|---|
| 460 | else
|
|---|
| 461 | {
|
|---|
| 462 | strcpy (alloc, name);
|
|---|
| 463 | p = strrchr (alloc, '_');
|
|---|
| 464 | *p++ = '\0';
|
|---|
| 465 | (*_bfd_error_handler)
|
|---|
| 466 | (_("Output file requires shared library `%s.so.%s'\n"),
|
|---|
| 467 | alloc, p);
|
|---|
| 468 | free (alloc);
|
|---|
| 469 | }
|
|---|
| 470 |
|
|---|
| 471 | abort ();
|
|---|
| 472 | }
|
|---|
| 473 |
|
|---|
| 474 | /* If this symbol is not a PLT/GOT, we do not even need to look at it */
|
|---|
| 475 | is_plt = IS_PLT_SYM (h->root.root.root.string);
|
|---|
| 476 |
|
|---|
| 477 | if (is_plt || IS_GOT_SYM (h->root.root.root.string))
|
|---|
| 478 | {
|
|---|
| 479 | /* Look up this symbol twice. Once just as a regular lookup,
|
|---|
| 480 | and then again following all of the indirect links until we
|
|---|
| 481 | reach a real symbol. */
|
|---|
| 482 | h1 = linux_link_hash_lookup (linux_hash_table (info),
|
|---|
| 483 | (h->root.root.root.string
|
|---|
| 484 | + sizeof PLT_REF_PREFIX - 1),
|
|---|
| 485 | FALSE, FALSE, TRUE);
|
|---|
| 486 | /* h2 does not follow indirect symbols. */
|
|---|
| 487 | h2 = linux_link_hash_lookup (linux_hash_table (info),
|
|---|
| 488 | (h->root.root.root.string
|
|---|
| 489 | + sizeof PLT_REF_PREFIX - 1),
|
|---|
| 490 | FALSE, FALSE, FALSE);
|
|---|
| 491 |
|
|---|
| 492 | /* The real symbol must exist but if it is also an ABS symbol,
|
|---|
| 493 | there is no need to have a fixup. This is because they both
|
|---|
| 494 | came from the same library. If on the other hand, we had to
|
|---|
| 495 | use an indirect symbol to get to the real symbol, we add the
|
|---|
| 496 | fixup anyway, since there are cases where these symbols come
|
|---|
| 497 | from different shared libraries */
|
|---|
| 498 | if (h1 != NULL
|
|---|
| 499 | && (((h1->root.root.type == bfd_link_hash_defined
|
|---|
| 500 | || h1->root.root.type == bfd_link_hash_defweak)
|
|---|
| 501 | && ! bfd_is_abs_section (h1->root.root.u.def.section))
|
|---|
| 502 | || h2->root.root.type == bfd_link_hash_indirect))
|
|---|
| 503 | {
|
|---|
| 504 | /* See if there is a "builtin" fixup already present
|
|---|
| 505 | involving this symbol. If so, convert it to a regular
|
|---|
| 506 | fixup. In the end, this relaxes some of the requirements
|
|---|
| 507 | about the order of performing fixups. */
|
|---|
| 508 | exists = FALSE;
|
|---|
| 509 | for (f1 = linux_hash_table (info)->fixup_list;
|
|---|
| 510 | f1 != NULL;
|
|---|
| 511 | f1 = f1->next)
|
|---|
| 512 | {
|
|---|
| 513 | if ((f1->h != h && f1->h != h1)
|
|---|
| 514 | || (! f1->builtin && ! f1->jump))
|
|---|
| 515 | continue;
|
|---|
| 516 | if (f1->h == h1)
|
|---|
| 517 | exists = TRUE;
|
|---|
| 518 | if (! exists
|
|---|
| 519 | && bfd_is_abs_section (h->root.root.u.def.section))
|
|---|
| 520 | {
|
|---|
| 521 | f = new_fixup (info, h1, f1->h->root.root.u.def.value, 0);
|
|---|
| 522 | f->jump = is_plt;
|
|---|
| 523 | }
|
|---|
| 524 | f1->h = h1;
|
|---|
| 525 | f1->jump = is_plt;
|
|---|
| 526 | f1->builtin = 0;
|
|---|
| 527 | exists = TRUE;
|
|---|
| 528 | }
|
|---|
| 529 | if (! exists
|
|---|
| 530 | && bfd_is_abs_section (h->root.root.u.def.section))
|
|---|
| 531 | {
|
|---|
| 532 | f = new_fixup (info, h1, h->root.root.u.def.value, 0);
|
|---|
| 533 | if (f == NULL)
|
|---|
| 534 | {
|
|---|
| 535 | /* FIXME: No way to return error. */
|
|---|
| 536 | abort ();
|
|---|
| 537 | }
|
|---|
| 538 | f->jump = is_plt;
|
|---|
| 539 | }
|
|---|
| 540 | }
|
|---|
| 541 |
|
|---|
| 542 | /* Quick and dirty way of stripping these symbols from the
|
|---|
| 543 | symtab. */
|
|---|
| 544 | if (bfd_is_abs_section (h->root.root.u.def.section))
|
|---|
| 545 | h->root.written = TRUE;
|
|---|
| 546 | }
|
|---|
| 547 |
|
|---|
| 548 | return TRUE;
|
|---|
| 549 | }
|
|---|
| 550 |
|
|---|
| 551 | /* This is called to set the size of the .linux-dynamic section is.
|
|---|
| 552 | It is called by the Linux linker emulation before_allocation
|
|---|
| 553 | routine. We have finished reading all of the input files, and now
|
|---|
| 554 | we just scan the hash tables to find out how many additional fixups
|
|---|
| 555 | are required. */
|
|---|
| 556 |
|
|---|
| 557 | bfd_boolean
|
|---|
| 558 | bfd_i386linux_size_dynamic_sections (output_bfd, info)
|
|---|
| 559 | bfd *output_bfd;
|
|---|
| 560 | struct bfd_link_info *info;
|
|---|
| 561 | {
|
|---|
| 562 | struct fixup *f;
|
|---|
| 563 | asection *s;
|
|---|
| 564 |
|
|---|
| 565 | if (output_bfd->xvec != &MY(vec))
|
|---|
| 566 | return TRUE;
|
|---|
| 567 |
|
|---|
| 568 | /* First find the fixups... */
|
|---|
| 569 | linux_link_hash_traverse (linux_hash_table (info),
|
|---|
| 570 | linux_tally_symbols,
|
|---|
| 571 | (PTR) info);
|
|---|
| 572 |
|
|---|
| 573 | /* If there are builtin fixups, leave room for a marker. This is
|
|---|
| 574 | used by the dynamic linker so that it knows that all that follow
|
|---|
| 575 | are builtin fixups instead of regular fixups. */
|
|---|
| 576 | for (f = linux_hash_table (info)->fixup_list; f != NULL; f = f->next)
|
|---|
| 577 | {
|
|---|
| 578 | if (f->builtin)
|
|---|
| 579 | {
|
|---|
| 580 | ++linux_hash_table (info)->fixup_count;
|
|---|
| 581 | ++linux_hash_table (info)->local_builtins;
|
|---|
| 582 | break;
|
|---|
| 583 | }
|
|---|
| 584 | }
|
|---|
| 585 |
|
|---|
| 586 | if (linux_hash_table (info)->dynobj == NULL)
|
|---|
| 587 | {
|
|---|
| 588 | if (linux_hash_table (info)->fixup_count > 0)
|
|---|
| 589 | abort ();
|
|---|
| 590 | return TRUE;
|
|---|
| 591 | }
|
|---|
| 592 |
|
|---|
| 593 | /* Allocate memory for our fixup table. We will fill it in later. */
|
|---|
| 594 | s = bfd_get_section_by_name (linux_hash_table (info)->dynobj,
|
|---|
| 595 | ".linux-dynamic");
|
|---|
| 596 | if (s != NULL)
|
|---|
| 597 | {
|
|---|
| 598 | s->_raw_size = linux_hash_table (info)->fixup_count + 1;
|
|---|
| 599 | s->_raw_size *= 8;
|
|---|
| 600 | s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
|
|---|
| 601 | if (s->contents == NULL)
|
|---|
| 602 | return FALSE;
|
|---|
| 603 | }
|
|---|
| 604 |
|
|---|
| 605 | return TRUE;
|
|---|
| 606 | }
|
|---|
| 607 |
|
|---|
| 608 | /* We come here once we are ready to actually write the fixup table to
|
|---|
| 609 | the output file. Scan the fixup tables and so forth and generate
|
|---|
| 610 | the stuff we need. */
|
|---|
| 611 |
|
|---|
| 612 | static bfd_boolean
|
|---|
| 613 | linux_finish_dynamic_link (output_bfd, info)
|
|---|
| 614 | bfd *output_bfd;
|
|---|
| 615 | struct bfd_link_info *info;
|
|---|
| 616 | {
|
|---|
| 617 | asection *s, *os, *is;
|
|---|
| 618 | bfd_byte *fixup_table;
|
|---|
| 619 | struct linux_link_hash_entry *h;
|
|---|
| 620 | struct fixup *f;
|
|---|
| 621 | unsigned int new_addr;
|
|---|
| 622 | int section_offset;
|
|---|
| 623 | unsigned int fixups_written;
|
|---|
| 624 |
|
|---|
| 625 | if (linux_hash_table (info)->dynobj == NULL)
|
|---|
| 626 | return TRUE;
|
|---|
| 627 |
|
|---|
| 628 | s = bfd_get_section_by_name (linux_hash_table (info)->dynobj,
|
|---|
| 629 | ".linux-dynamic");
|
|---|
| 630 | BFD_ASSERT (s != NULL);
|
|---|
| 631 | os = s->output_section;
|
|---|
| 632 | fixups_written = 0;
|
|---|
| 633 |
|
|---|
| 634 | #ifdef LINUX_LINK_DEBUG
|
|---|
| 635 | printf ("Fixup table file offset: %x VMA: %x\n",
|
|---|
| 636 | os->filepos + s->output_offset,
|
|---|
| 637 | os->vma + s->output_offset);
|
|---|
| 638 | #endif
|
|---|
| 639 |
|
|---|
| 640 | fixup_table = s->contents;
|
|---|
| 641 | bfd_put_32 (output_bfd,
|
|---|
| 642 | (bfd_vma) linux_hash_table (info)->fixup_count, fixup_table);
|
|---|
| 643 | fixup_table += 4;
|
|---|
| 644 |
|
|---|
| 645 | /* Fill in fixup table. */
|
|---|
| 646 | for (f = linux_hash_table (info)->fixup_list; f != NULL; f = f->next)
|
|---|
| 647 | {
|
|---|
| 648 | if (f->builtin)
|
|---|
| 649 | continue;
|
|---|
| 650 |
|
|---|
| 651 | if (f->h->root.root.type != bfd_link_hash_defined
|
|---|
| 652 | && f->h->root.root.type != bfd_link_hash_defweak)
|
|---|
| 653 | {
|
|---|
| 654 | (*_bfd_error_handler)
|
|---|
| 655 | (_("Symbol %s not defined for fixups\n"),
|
|---|
| 656 | f->h->root.root.root.string);
|
|---|
| 657 | continue;
|
|---|
| 658 | }
|
|---|
| 659 |
|
|---|
| 660 | is = f->h->root.root.u.def.section;
|
|---|
| 661 | section_offset = is->output_section->vma + is->output_offset;
|
|---|
| 662 | new_addr = f->h->root.root.u.def.value + section_offset;
|
|---|
| 663 |
|
|---|
| 664 | #ifdef LINUX_LINK_DEBUG
|
|---|
| 665 | printf ("Fixup(%d) %s: %x %x\n",f->jump, f->h->root.root.string,
|
|---|
| 666 | new_addr, f->value);
|
|---|
| 667 | #endif
|
|---|
| 668 |
|
|---|
| 669 | if (f->jump)
|
|---|
| 670 | {
|
|---|
| 671 | /* Relative address */
|
|---|
| 672 | new_addr = new_addr - (f->value + 5);
|
|---|
| 673 | bfd_put_32 (output_bfd, (bfd_vma) new_addr, fixup_table);
|
|---|
| 674 | fixup_table += 4;
|
|---|
| 675 | bfd_put_32 (output_bfd, f->value + 1, fixup_table);
|
|---|
| 676 | fixup_table += 4;
|
|---|
| 677 | }
|
|---|
| 678 | else
|
|---|
| 679 | {
|
|---|
| 680 | bfd_put_32 (output_bfd, (bfd_vma) new_addr, fixup_table);
|
|---|
| 681 | fixup_table += 4;
|
|---|
| 682 | bfd_put_32 (output_bfd, f->value, fixup_table);
|
|---|
| 683 | fixup_table += 4;
|
|---|
| 684 | }
|
|---|
| 685 | ++fixups_written;
|
|---|
| 686 | }
|
|---|
| 687 |
|
|---|
| 688 | if (linux_hash_table (info)->local_builtins != 0)
|
|---|
| 689 | {
|
|---|
| 690 | /* Special marker so we know to switch to the other type of fixup */
|
|---|
| 691 | bfd_put_32 (output_bfd, (bfd_vma) 0, fixup_table);
|
|---|
| 692 | fixup_table += 4;
|
|---|
| 693 | bfd_put_32 (output_bfd, (bfd_vma) 0, fixup_table);
|
|---|
| 694 | fixup_table += 4;
|
|---|
| 695 | ++fixups_written;
|
|---|
| 696 | for (f = linux_hash_table (info)->fixup_list; f != NULL; f = f->next)
|
|---|
| 697 | {
|
|---|
| 698 | if (! f->builtin)
|
|---|
| 699 | continue;
|
|---|
| 700 |
|
|---|
| 701 | if (f->h->root.root.type != bfd_link_hash_defined
|
|---|
| 702 | && f->h->root.root.type != bfd_link_hash_defweak)
|
|---|
| 703 | {
|
|---|
| 704 | (*_bfd_error_handler)
|
|---|
| 705 | (_("Symbol %s not defined for fixups\n"),
|
|---|
| 706 | f->h->root.root.root.string);
|
|---|
| 707 | continue;
|
|---|
| 708 | }
|
|---|
| 709 |
|
|---|
| 710 | is = f->h->root.root.u.def.section;
|
|---|
| 711 | section_offset = is->output_section->vma + is->output_offset;
|
|---|
| 712 | new_addr = f->h->root.root.u.def.value + section_offset;
|
|---|
| 713 |
|
|---|
| 714 | #ifdef LINUX_LINK_DEBUG
|
|---|
| 715 | printf ("Fixup(B) %s: %x %x\n", f->h->root.root.string,
|
|---|
| 716 | new_addr, f->value);
|
|---|
| 717 | #endif
|
|---|
| 718 |
|
|---|
| 719 | bfd_put_32 (output_bfd, (bfd_vma) new_addr, fixup_table);
|
|---|
| 720 | fixup_table += 4;
|
|---|
| 721 | bfd_put_32 (output_bfd, f->value, fixup_table);
|
|---|
| 722 | fixup_table += 4;
|
|---|
| 723 | ++fixups_written;
|
|---|
| 724 | }
|
|---|
| 725 | }
|
|---|
| 726 |
|
|---|
| 727 | if (linux_hash_table (info)->fixup_count != fixups_written)
|
|---|
| 728 | {
|
|---|
| 729 | (*_bfd_error_handler) (_("Warning: fixup count mismatch\n"));
|
|---|
| 730 | while (linux_hash_table (info)->fixup_count > fixups_written)
|
|---|
| 731 | {
|
|---|
| 732 | bfd_put_32 (output_bfd, (bfd_vma) 0, fixup_table);
|
|---|
| 733 | fixup_table += 4;
|
|---|
| 734 | bfd_put_32 (output_bfd, (bfd_vma) 0, fixup_table);
|
|---|
| 735 | fixup_table += 4;
|
|---|
| 736 | ++fixups_written;
|
|---|
| 737 | }
|
|---|
| 738 | }
|
|---|
| 739 |
|
|---|
| 740 | h = linux_link_hash_lookup (linux_hash_table (info),
|
|---|
| 741 | "__BUILTIN_FIXUPS__",
|
|---|
| 742 | FALSE, FALSE, FALSE);
|
|---|
| 743 |
|
|---|
| 744 | if (h != NULL
|
|---|
| 745 | && (h->root.root.type == bfd_link_hash_defined
|
|---|
| 746 | || h->root.root.type == bfd_link_hash_defweak))
|
|---|
| 747 | {
|
|---|
| 748 | is = h->root.root.u.def.section;
|
|---|
| 749 | section_offset = is->output_section->vma + is->output_offset;
|
|---|
| 750 | new_addr = h->root.root.u.def.value + section_offset;
|
|---|
| 751 |
|
|---|
| 752 | #ifdef LINUX_LINK_DEBUG
|
|---|
| 753 | printf ("Builtin fixup table at %x\n", new_addr);
|
|---|
| 754 | #endif
|
|---|
| 755 |
|
|---|
| 756 | bfd_put_32 (output_bfd, (bfd_vma) new_addr, fixup_table);
|
|---|
| 757 | }
|
|---|
| 758 | else
|
|---|
| 759 | bfd_put_32 (output_bfd, (bfd_vma) 0, fixup_table);
|
|---|
| 760 |
|
|---|
| 761 | if (bfd_seek (output_bfd, (file_ptr) (os->filepos + s->output_offset),
|
|---|
| 762 | SEEK_SET) != 0)
|
|---|
| 763 | return FALSE;
|
|---|
| 764 |
|
|---|
| 765 | if (bfd_bwrite ((PTR) s->contents, s->_raw_size, output_bfd) != s->_raw_size)
|
|---|
| 766 | return FALSE;
|
|---|
| 767 |
|
|---|
| 768 | return TRUE;
|
|---|
| 769 | }
|
|---|
| 770 |
|
|---|
| 771 | #define MY_bfd_link_hash_table_create linux_link_hash_table_create
|
|---|
| 772 | #define MY_add_one_symbol linux_add_one_symbol
|
|---|
| 773 | #define MY_finish_dynamic_link linux_finish_dynamic_link
|
|---|
| 774 |
|
|---|
| 775 | #define MY_zmagic_contiguous 1
|
|---|
| 776 |
|
|---|
| 777 | #include "aout-target.h"
|
|---|