| blob | 1dfed2fdd1508bcf33cb82c7e25ed7f289f292bd |
1 /* ELF linking support for BFD.
2 Copyright (C) 1995-2021 Free Software Foundation, Inc.
4 This file is part of BFD, the Binary File Descriptor library.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
19 MA 02110-1301, USA. */
25 #define ARCH_SIZE 0
30 #if BFD_SUPPORTS_PLUGINS
33 #endif
35 #ifdef HAVE_LIMITS_H
36 #include <limits.h>
37 #endif
38 #ifndef CHAR_BIT
39 #define CHAR_BIT 8
40 #endif
42 /* This struct is used to pass information to routines called via
43 elf_link_hash_traverse which must return failure. */
45 struct elf_info_failed
46 {
48 bfd_boolean failed;
49 };
51 /* This structure is used to pass information to
52 _bfd_elf_link_find_version_dependencies. */
54 struct elf_find_verdep_info
55 {
56 /* General link information. */
58 /* The number of dependencies. */
60 /* Whether we had a failure. */
61 bfd_boolean failed;
62 };
64 static bfd_boolean _bfd_elf_fix_symbol_flags
67 asection *
70 bfd_boolean discard)
71 {
74 {
87 else
89 }
90 else
91 {
92 /* It's not a relocation against a global symbol,
93 but it could be a relocation against a local
94 symbol for a discarded section. */
98 /* Need to: get the symbol; get the section. */
104 }
106 }
108 /* Define a symbol in a dynamic linkage section. */
115 {
122 {
123 /* Zap symbol defined in an as-needed lib that wasn't linked.
124 This is a symptom of a larger problem: Absolute symbols
125 defined in shared libraries can't be overridden, because we
126 lose the link to the bfd which is via the symbol section. */
129 }
130 else
149 }
151 bfd_boolean
153 {
154 flagword flags;
160 /* This function may be called more than once. */
183 {
189 }
191 /* The first bit of the global offset table is the header. */
195 {
196 /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got
197 (or .got.plt) section. We don't do this in the linker script
198 because we don't want to define the symbol if we are not creating
199 a global offset table. */
205 }
208 }
209 \f
210 /* Create a strtab to hold the dynamic symbol names. */
211 static bfd_boolean
213 {
218 {
219 /* We may not set dynobj, an input file holding linker created
220 dynamic sections to abfd, which may be a dynamic object with
221 its own dynamic sections. We need to find a normal input file
222 to hold linker created sections if possible. */
224 {
234 {
237 }
238 }
240 }
243 {
247 }
249 }
251 /* Create some sections which will be filled in with dynamic linking
252 information. ABFD is an input file which requires dynamic sections
253 to be created. The dynamic sections take up virtual memory space
254 when the final executable is run, so we need to create them before
255 addresses are assigned to the output sections. We work out the
256 actual contents and size of these sections later. */
258 bfd_boolean
260 {
261 flagword flags;
280 /* A dynamically linked executable has a .interp section, but a
281 shared library does not. */
283 {
288 }
290 /* Create sections to hold version informations. These are removed
291 if they are not needed. */
327 /* The special symbol _DYNAMIC is always set to the start of the
328 .dynamic section. We could set _DYNAMIC in a linker script, but we
329 only want to define it if we are, in fact, creating a .dynamic
330 section. We don't want to define it if there is no .dynamic
331 section, since on some ELF platforms the start up code examines it
332 to decide how to initialize the process. */
339 {
346 }
349 {
355 /* For 64-bit ELF, .gnu.hash is a non-uniform entity size section:
356 4 32-bit words followed by variable count of 64-bit words, then
357 variable count of 32-bit words. */
360 else
362 }
364 /* Let the backend create the rest of the sections. This lets the
365 backend set the right flags. The backend will normally create
366 the .got and .plt sections. */
374 }
376 /* Create dynamic sections when linking against a dynamic object. */
378 bfd_boolean
380 {
387 /* We need to create .plt, .rel[a].plt, .got, .got.plt, .dynbss, and
388 .rel[a].bss sections. */
393 /* We do not clear SEC_ALLOC here because we still want the OS to
394 allocate space for the section; it's just that there's nothing
395 to read in from the object file. */
397 else
408 /* Define the symbol _PROCEDURE_LINKAGE_TABLE_ at the start of the
409 .plt section. */
411 {
417 }
432 {
433 /* The .dynbss section is a place to put symbols which are defined
434 by dynamic objects, are referenced by regular objects, and are
435 not functions. We must allocate space for them in the process
436 image and use a R_*_COPY reloc to tell the dynamic linker to
437 initialize them at run time. The linker script puts the .dynbss
438 section into the .bss section of the final image. */
446 {
447 /* Similarly, but for symbols that were originally in read-only
448 sections. This section doesn't really need to have contents,
449 but make it like other .data.rel.ro sections. */
451 flags);
455 }
457 /* The .rel[a].bss section holds copy relocs. This section is not
458 normally needed. We need to create it here, though, so that the
459 linker will map it to an output section. We can't just create it
460 only if we need it, because we will not know whether we need it
461 until we have seen all the input files, and the first time the
462 main linker code calls BFD after examining all the input files
463 (size_dynamic_sections) the input sections have already been
464 mapped to the output sections. If the section turns out not to
465 be needed, we can discard it later. We will never need this
466 section when generating a shared object, since they do not use
467 copy relocs. */
469 {
480 {
481 s = (bfd_make_section_anyway_with_flags
489 }
490 }
491 }
494 }
495 \f
496 /* Record a new dynamic symbol. We record the dynamic symbols as we
497 read the input files, since we need to have a list of all of them
498 before we can determine the final sizes of the output sections.
499 Note that we may actually call this function even though we are not
500 going to output any dynamic symbols; in some cases we know that a
501 symbol should be in the dynamic symbol table, but only if there is
502 one. */
504 bfd_boolean
507 {
509 {
517 {
518 /* An IR symbol should not be made dynamic. */
523 }
525 /* XXX: The ABI draft says the linker must turn hidden and
526 internal symbols into STB_LOCAL symbols when producing the
527 DSO. However, if ld.so honors st_other in the dynamic table,
528 this would not be necessary. */
530 {
535 {
539 }
543 }
550 {
551 /* Create a strtab to hold the dynamic symbol names. */
555 }
557 /* We don't put any version information in the dynamic string
558 table. */
562 /* We know that the p points into writable memory. In fact,
563 there are only a few symbols that have read-only names, being
564 those like _GLOBAL_OFFSET_TABLE_ that are created specially
565 by the backends. Most symbols will have names pointing into
566 an ELF string table read from a file, or to objalloc memory. */
577 }
580 }
581 \f
582 /* Mark a symbol dynamic. */
584 static void
588 {
591 /* It may be called more than once on the same H. */
604 {
606 /* NB: If a symbol is made dynamic by --dynamic-list, it has
607 non-IR reference. */
609 }
610 }
612 /* Record an assignment to a symbol made by a linker script. We need
613 this in case some dynamic object refers to this symbol. */
615 bfd_boolean
619 bfd_boolean provide,
620 bfd_boolean hidden)
621 {
638 {
639 /* Set versioned if symbol version is unknown. */
642 {
645 else
647 }
648 }
650 /* Symbols defined in a linker script but not referenced anywhere
651 else will have non_elf set. */
653 {
656 }
659 {
666 /* Since we're defining the symbol, don't let it seem to have not
667 been defined. record_dynamic_symbol and size_dynamic_sections
668 may depend on this. */
676 /* We had a versioned symbol in a dynamic library. We make the
677 the versioned symbol point to this one. */
683 /* We don't need to update h->root.u since linker will set them
684 later. */
693 }
695 /* If this symbol is being provided by the linker script, and it is
696 currently defined by a dynamic object, but not by a regular
697 object, then mark it as undefined so that the generic linker will
698 force the correct value. */
704 /* If this symbol is currently defined by a dynamic object, but not
705 by a regular object, then clear out any version information because
706 the symbol will not be associated with the dynamic object any
707 more. */
711 /* Make sure this symbol is not garbage collected. */
717 {
722 }
724 /* STV_HIDDEN and STV_INTERNAL symbols must be STB_LOCAL in shared objects
725 and executables. */
738 {
742 /* If this is a weak defined symbol, and we know a corresponding
743 real symbol from the same dynamic object, make sure the real
744 symbol is also made into a dynamic symbol. */
746 {
752 }
753 }
756 }
758 /* Record a new local dynamic symbol. Returns 0 on failure, 1 on
759 success, and 2 on a failure caused by attempting to record a symbol
760 in a discarded section, eg. a discarded link-once section symbol. */
762 int
766 {
773 Elf_External_Sym_Shndx eshndx;
779 /* See if the entry exists already. */
789 /* Go find the symbol, so that we can find it's name. */
792 {
795 }
799 {
804 {
805 /* We can still bfd_release here as nothing has done another
806 bfd_alloc. We can't do this later in this function. */
809 }
810 }
812 name = (bfd_elf_string_from_elf_section
818 {
819 /* Create a strtab to hold the dynamic symbol names. */
823 }
838 /* Whatever binding the symbol had before, it's now local. */
842 /* The dynindx will be set at the end of size_dynamic_sections. */
845 }
847 /* Return the dynindex of a local dynamic symbol. */
849 long
853 {
860 }
862 /* This function is used to renumber the dynamic symbols, if some of
863 them are removed because they are marked as local. This is called
864 via elf_link_hash_traverse. */
866 static bfd_boolean
869 {
879 }
882 /* Like elf_link_renumber_hash_table_dynsyms, but just number symbols with
883 STB_LOCAL binding. */
885 static bfd_boolean
888 {
898 }
900 /* Return true if the dynamic symbol for a given section should be
901 omitted when creating a shared library. */
902 bfd_boolean
906 {
911 {
914 /* If sh_type is yet undecided, assume it could be
915 SHT_PROGBITS/SHT_NOBITS. */
925 /* There shouldn't be section relative relocations
926 against any other section. */
929 }
930 }
932 bfd_boolean
933 _bfd_elf_omit_section_dynsym_all
937 {
939 }
941 /* Assign dynsym indices. In a shared library we generate a section
942 symbol for each output section, which come first. Next come symbols
943 which have been forced to local binding. Then all of the back-end
944 allocated local dynamic syms, followed by the rest of the global
945 symbols. If SECTION_SYM_COUNT is NULL, section dynindx is not set.
946 (This prevents the early call before elf_backend_init_index_section
947 and strip_excluded_output_sections setting dynindx for sections
948 that are stripped.) */
950 static unsigned long
954 {
960 {
968 {
972 }
975 }
980 elf_link_renumber_local_hash_table_dynsyms,
984 {
988 }
992 elf_link_renumber_hash_table_dynsyms,
995 /* There is an unused NULL entry at the head of the table which we
996 must account for in our count even if the table is empty since it
997 is intended for the mandatory DT_SYMTAB tag (.dynsym section) in
998 .dynamic section. */
999 dynsymcount++;
1003 }
1005 /* Merge st_other field. */
1007 static void
1011 {
1014 /* If st_other has a processor-specific meaning, specific
1015 code might be needed here. */
1018 dynamic);
1021 {
1025 /* Keep the most constraining visibility. Leave the remainder
1026 of the st_other field to elf_backend_merge_symbol_attribute. */
1029 }
1034 }
1036 /* This function is called when we want to merge a new symbol with an
1037 existing symbol. It handles the various cases which arise when we
1038 find a definition in a dynamic object, or when there is already a
1039 definition in a dynamic object. The new symbol is described by
1040 NAME, SYM, PSEC, and PVALUE. We set SYM_HASH to the hash table
1041 entry. We set POLDBFD to the old symbol's BFD. We set POLD_WEAK
1042 if the old symbol was weak. We set POLD_ALIGNMENT to the alignment
1043 of an old common symbol. We set OVERRIDE if the old symbol is
1044 overriding a new definition. We set TYPE_CHANGE_OK if it is OK for
1045 the type to change. We set SIZE_CHANGE_OK if it is OK for the size
1046 to change. By OK to change, we mean that we shouldn't warn if the
1047 type or size does change. */
1049 static bfd_boolean
1065 {
1086 else
1095 /* NEW_VERSION is the symbol version of the new symbol. */
1097 {
1098 /* Symbol version is unknown or versioned. */
1101 {
1103 {
1106 else
1108 }
1112 }
1113 else
1115 }
1116 else
1119 /* For merging, we only care about real symbols. But we need to make
1120 sure that indirect symbol dynamic flags are updated. */
1127 {
1130 else
1131 {
1132 /* OLD_HIDDEN is true if the existing symbol is only visible
1133 to the symbol with the same symbol version. NEW_HIDDEN is
1134 true if the new symbol is only visible to the symbol with
1135 the same symbol version. */
1139 /* The new symbol matches the existing symbol if both
1140 aren't hidden. */
1142 else
1143 {
1144 /* OLD_VERSION is the symbol version of the existing
1145 symbol. */
1151 else
1154 /* The new symbol matches the existing symbol if they
1155 have the same symbol version. */
1160 }
1161 }
1162 }
1164 /* OLDBFD and OLDSEC are a BFD and an ASECTION associated with the
1165 existing symbol. */
1170 {
1191 }
1195 /* Differentiate strong and weak symbols. */
1202 /* We have to check it for every instance since the first few may be
1203 references and not all compilers emit symbol type for undefined
1204 symbols. */
1207 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
1208 respectively, is from a dynamic object. */
1212 /* ref_dynamic_nonweak and dynamic_def flags track actual undefined
1213 syms and defined syms in dynamic libraries respectively.
1214 ref_dynamic on the other hand can be set for a symbol defined in
1215 a dynamic library, and def_dynamic may not be set; When the
1216 definition in a dynamic lib is overridden by a definition in the
1217 executable use of the symbol in the dynamic lib becomes a
1218 reference to the executable symbol. */
1220 {
1222 {
1224 {
1227 }
1228 }
1229 else
1230 {
1231 /* Update the existing symbol only if they match. */
1235 }
1236 }
1238 /* If we just created the symbol, mark it as being an ELF symbol.
1239 Other than that, there is nothing to do--there is no merge issue
1240 with a newly defined symbol--so we just return. */
1243 {
1246 }
1248 /* In cases involving weak versioned symbols, we may wind up trying
1249 to merge a symbol with itself. Catch that here, to avoid the
1250 confusion that results if we try to override a symbol with
1251 itself. The additional tests catch cases like
1252 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
1253 dynamic object, which we do want to handle here. */
1264 {
1265 /* This handles the special SHN_MIPS_{TEXT,DATA} section
1266 indices used by MIPS ELF. */
1268 }
1270 /* Handle a case where plugin_notice won't be called and thus won't
1271 set the non_ir_ref flags on the first pass over symbols. */
1275 {
1278 }
1280 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
1281 respectively, appear to be a definition rather than reference. */
1289 /* NEWFUNC and OLDFUNC indicate whether the new or old symbol,
1290 respectively, appear to be a function. */
1304 {
1305 /* If creating a default indirect symbol ("foo" or "foo@") from
1306 a dynamic versioned definition ("foo@@") skip doing so if
1307 there is an existing regular definition with a different
1308 type. We don't want, for example, a "time" variable in the
1309 executable overriding a "time" function in a shared library. */
1312 {
1315 }
1317 /* When adding a symbol from a regular object file after we have
1318 created indirect symbols, undo the indirection and any
1319 dynamic state. */
1321 && !newdyn
1323 {
1331 {
1334 }
1335 else
1336 {
1339 }
1341 }
1342 }
1344 /* Check TLS symbols. We don't check undefined symbols introduced
1345 by "ld -u" which have no type (and oldbfd NULL), and we don't
1346 check symbols from plugins because they also have no type. */
1352 {
1358 {
1365 }
1366 else
1367 {
1374 }
1377 _bfd_error_handler
1378 /* xgettext:c-format */
1383 _bfd_error_handler
1384 /* xgettext:c-format */
1389 _bfd_error_handler
1390 /* xgettext:c-format */
1394 else
1395 _bfd_error_handler
1396 /* xgettext:c-format */
1403 }
1405 /* If the old symbol has non-default visibility, we ignore the new
1406 definition from a dynamic object. */
1410 {
1412 /* Make sure this symbol is dynamic. */
1415 /* A protected symbol has external availability. Make sure it is
1416 recorded as dynamic.
1418 FIXME: Should we check type and size for protected symbol? */
1421 else
1423 }
1427 {
1428 /* If the new symbol with non-default visibility comes from a
1429 relocatable file and the old definition comes from a dynamic
1430 object, we remove the old definition. */
1432 {
1433 /* Handle the case where the old dynamic definition is
1434 default versioned. We need to copy the symbol info from
1435 the symbol with default version to the normal one if it
1436 was referenced before. */
1438 {
1445 {
1446 /* If the new symbol is hidden or internal, completely undo
1447 any dynamic link state. */
1451 }
1452 else
1456 /* FIXME: Should we check type and size for protected symbol? */
1461 }
1462 else
1464 }
1466 /* If the old symbol was undefined before, then it will still be
1467 on the undefs list. If the new symbol is undefined or
1468 common, we can't make it bfd_link_hash_new here, because new
1469 undefined or common symbols will be added to the undefs list
1470 by _bfd_generic_link_add_one_symbol. Symbols may not be
1471 added twice to the undefs list. Also, if the new symbol is
1472 undefweak then we don't want to lose the strong undef. */
1474 {
1477 }
1478 else
1479 {
1482 }
1485 {
1486 /* If the new symbol is hidden or internal, completely undo
1487 any dynamic link state. */
1491 }
1492 else
1495 /* FIXME: Should we check type and size for protected symbol? */
1499 }
1501 /* If a new weak symbol definition comes from a regular file and the
1502 old symbol comes from a dynamic library, we treat the new one as
1503 strong. Similarly, an old weak symbol definition from a regular
1504 file is treated as strong when the new symbol comes from a dynamic
1505 library. Further, an old weak symbol from a dynamic library is
1506 treated as strong if the new symbol is from a dynamic library.
1507 This reflects the way glibc's ld.so works.
1509 Also allow a weak symbol to override a linker script symbol
1510 defined by an early pass over the script. This is done so the
1511 linker knows the symbol is defined in an object file, for the
1512 DEFINED script function.
1514 Do this before setting *type_change_ok or *size_change_ok so that
1515 we warn properly when dynamic library symbols are overridden. */
1522 /* Allow changes between different types of function symbol. */
1526 /* It's OK to change the type if either the existing symbol or the
1527 new symbol is weak. A type change is also OK if the old symbol
1528 is undefined and the new symbol is defined. */
1531 || newweak
1532 || (newdef
1536 /* It's OK to change the size if either the existing symbol or the
1537 new symbol is weak, or if the old symbol is undefined. */
1543 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
1544 symbol, respectively, appears to be a common symbol in a dynamic
1545 object. If a symbol appears in an uninitialized section, and is
1546 not weak, and is not a function, then it may be a common symbol
1547 which was resolved when the dynamic object was created. We want
1548 to treat such symbols specially, because they raise special
1549 considerations when setting the symbol size: if the symbol
1550 appears as a common symbol in a regular object, and the size in
1551 the regular object is larger, we must make sure that we use the
1552 larger size. This problematic case can always be avoided in C,
1553 but it must be handled correctly when using Fortran shared
1554 libraries.
1556 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
1557 likewise for OLDDYNCOMMON and OLDDEF.
1559 Note that this test is just a heuristic, and that it is quite
1560 possible to have an uninitialized symbol in a shared object which
1561 is really a definition, rather than a common symbol. This could
1562 lead to some minor confusion when the symbol really is a common
1563 symbol in some regular object. However, I think it will be
1564 harmless. */
1567 && newdef
1568 && !newweak
1574 else
1578 && olddef
1586 else
1589 /* We now know everything about the old and new symbols. We ask the
1590 backend to check if we can merge them. */
1592 {
1596 }
1598 /* There are multiple definitions of a normal symbol. Skip the
1599 default symbol as well as definition from an IR object. */
1605 {
1606 /* Handle a multiple definition. */
1611 }
1613 /* If both the old and the new symbols look like common symbols in a
1614 dynamic object, set the size of the symbol to the larger of the
1615 two. */
1618 && newdyncommon
1620 {
1621 /* Since we think we have two common symbols, issue a multiple
1622 common warning if desired. Note that we only warn if the
1623 size is different. If the size is the same, we simply let
1624 the old symbol override the new one as normally happens with
1625 symbols defined in dynamic objects. */
1633 }
1635 /* If we are looking at a dynamic object, and we have found a
1636 definition, we need to see if the symbol was already defined by
1637 some other object. If so, we want to use the existing
1638 definition, and we do not want to report a multiple symbol
1639 definition error; we do this by clobbering *PSEC to be
1640 bfd_und_section_ptr.
1642 We treat a common symbol as a definition if the symbol in the
1643 shared library is a function, since common symbols always
1644 represent variables; this can cause confusion in principle, but
1645 any such confusion would seem to indicate an erroneous program or
1646 shared library. We also permit a common symbol in a regular
1647 object to override a weak symbol in a shared object. */
1650 && newdef
1651 && (olddef
1654 {
1662 /* If we get here when the old symbol is a common symbol, then
1663 we are explicitly letting it override a weak symbol or
1664 function in a dynamic object, and we don't want to warn about
1665 a type change. If the old symbol is a defined symbol, a type
1666 change warning may still be appropriate. */
1670 }
1672 /* Handle the special case of an old common symbol merging with a
1673 new symbol which looks like a common symbol in a shared object.
1674 We change *PSEC and *PVALUE to make the new symbol look like a
1675 common symbol, and let _bfd_generic_link_add_one_symbol do the
1676 right thing. */
1680 {
1687 }
1689 /* Skip weak definitions of symbols that are already defined. */
1691 {
1692 /* Don't skip new non-IR weak syms. */
1696 {
1699 }
1701 /* Merge st_other. If the symbol already has a dynamic index,
1702 but visibility says it should not be visible, turn it into a
1703 local symbol. */
1707 {
1712 }
1713 }
1715 /* If the old symbol is from a dynamic object, and the new symbol is
1716 a definition which is not from a dynamic object, then the new
1717 symbol overrides the old symbol. Symbols from regular files
1718 always take precedence over symbols from dynamic objects, even if
1719 they are defined after the dynamic object in the link.
1721 As above, we again permit a common symbol in a regular object to
1722 override a definition in a shared object if the shared object
1723 symbol is a function or is weak. */
1727 && (newdef
1730 && olddyn
1731 && olddef
1733 {
1734 /* Change the hash table entry to undefined, and let
1735 _bfd_generic_link_add_one_symbol do the right thing with the
1736 new definition. */
1745 /* We again permit a type change when a common symbol may be
1746 overriding a function. */
1749 {
1751 {
1752 /* If a common symbol overrides a function, make sure
1753 that it isn't defined dynamically nor has type
1754 function. */
1757 }
1759 }
1763 else
1764 /* This union may have been set to be non-NULL when this symbol
1765 was seen in a dynamic object. We must force the union to be
1766 NULL, so that it is correct for a regular symbol. */
1768 }
1770 /* Handle the special case of a new common symbol merging with an
1771 old symbol that looks like it might be a common symbol defined in
1772 a shared object. Note that we have already handled the case in
1773 which a new common symbol should simply override the definition
1774 in the shared library. */
1779 {
1780 /* It would be best if we could set the hash table entry to a
1781 common symbol, but we don't know what to use for the section
1782 or the alignment. */
1786 /* If the presumed common symbol in the dynamic object is
1787 larger, pretend that the new symbol has its size. */
1792 /* We need to remember the alignment required by the symbol
1793 in the dynamic object. */
1808 else
1810 }
1813 {
1814 /* Handle the case where we had a versioned symbol in a dynamic
1815 library and now find a definition in a normal object. In this
1816 case, we make the versioned symbol point to the normal one. */
1823 {
1826 }
1827 }
1830 }
1832 /* This function is called to create an indirect symbol from the
1833 default for the symbol with the default version if needed. The
1834 symbol is described by H, NAME, SYM, SEC, and VALUE. We
1835 set DYNSYM if the new indirect symbol is dynamic. */
1837 static bfd_boolean
1844 bfd_vma value,
1847 {
1848 bfd_boolean type_change_ok;
1849 bfd_boolean size_change_ok;
1850 bfd_boolean skip;
1855 bfd_boolean collect;
1856 bfd_boolean dynamic;
1861 bfd_boolean matched;
1866 /* If this symbol has a version, and it is the default version, we
1867 create an indirect symbol from the default name to the fully
1868 decorated name. This will cause external references which do not
1869 specify a version to be bound to this version of the symbol. */
1872 {
1874 {
1877 }
1878 else
1879 {
1881 {
1884 }
1885 else
1887 }
1888 }
1889 else
1890 {
1891 /* PR ld/19073: We may see an unversioned definition after the
1892 default version. */
1895 }
1908 /* We are going to create a new symbol. Merge it with any existing
1909 symbol with this name. For the purposes of the merge, act as
1910 though we were defining the symbol we just defined, although we
1911 actually going to define an indirect symbol. */
1925 {
1926 /* If the undecorated symbol will have a version added by a
1927 script different to H, then don't indirect to/from the
1928 undecorated symbol. This isn't ideal because we may not yet
1929 have seen symbol versions, if given by a script on the
1930 command line rather than via --version-script. */
1932 {
1933 bfd_boolean hide;
1939 {
1942 }
1943 }
1947 }
1950 {
1951 /* Add the default symbol if not performing a relocatable link. */
1953 {
1958 {
1959 /* Mark the previous definition from IR object as
1960 undefined so that the generic linker will override
1961 it. */
1964 }
1967 bfd_ind_section_ptr,
1971 }
1972 }
1973 else
1974 {
1975 /* In this case the symbol named SHORTNAME is overriding the
1976 indirect symbol we want to add. We were planning on making
1977 SHORTNAME an indirect symbol referring to NAME. SHORTNAME
1978 is the name without a version. NAME is the fully versioned
1979 name, and it is the default version.
1981 Overriding means that we already saw a definition for the
1982 symbol SHORTNAME in a regular object, and it is overriding
1983 the symbol defined in the dynamic object.
1985 When this happens, we actually want to change NAME, the
1986 symbol we just added, to refer to SHORTNAME. This will cause
1987 references to NAME in the shared object to become references
1988 to SHORTNAME in the regular object. This is what we expect
1989 when we override a function in a shared object: that the
1990 references in the shared object will be mapped to the
1991 definition in the regular object. */
2000 {
2005 {
2008 }
2009 }
2011 /* Now set HI to H, so that the following code will set the
2012 other fields correctly. */
2014 }
2016 /* Check if HI is a warning symbol. */
2020 /* If there is a duplicate definition somewhere, then HI may not
2021 point to an indirect symbol. We will have reported an error to
2022 the user in that case. */
2025 {
2031 /* If we first saw a reference to SHORTNAME with non-default
2032 visibility, merge that visibility to the @@VER symbol. */
2035 /* A reference to the SHORTNAME symbol from a dynamic library
2036 will be satisfied by the versioned symbol at runtime. In
2037 effect, we have a reference to the versioned symbol. */
2041 /* See if the new flags lead us to realize that the symbol must
2042 be dynamic. */
2044 {
2046 {
2051 }
2052 else
2053 {
2056 }
2057 }
2058 }
2060 /* We also need to define an indirection from the nondefault version
2061 of the symbol. */
2063 nondefault:
2071 /* Once again, merge with any existing symbol. */
2081 {
2085 {
2086 /* We are handling a weak sym@@ver and attempting to define
2087 a weak sym@ver, but _bfd_elf_merge_symbol said to skip the
2088 new weak sym@ver because there is already a strong sym@ver.
2089 However, sym@ver and sym@@ver are really the same symbol.
2090 The existing strong sym@ver ought to override sym@@ver. */
2096 }
2097 else
2099 }
2101 {
2102 /* Here SHORTNAME is a versioned name, so we don't expect to see
2103 the type of override we do in the case above unless it is
2104 overridden by a versioned definition. */
2107 _bfd_error_handler
2108 /* xgettext:c-format */
2112 }
2113 else
2114 {
2121 }
2123 /* If there is a duplicate definition somewhere, then HI may not
2124 point to an indirect symbol. We will have reported an error
2125 to the user in that case. */
2127 {
2132 /* If we first saw a reference to @VER symbol with
2133 non-default visibility, merge that visibility to the
2134 @@VER symbol. */
2137 /* See if the new flags lead us to realize that the symbol
2138 must be dynamic. */
2140 {
2142 {
2146 }
2147 else
2148 {
2151 }
2152 }
2153 }
2156 }
2157 \f
2158 /* This routine is used to export all defined symbols into the dynamic
2159 symbol table. It is called via elf_link_hash_traverse. */
2161 static bfd_boolean
2163 {
2166 /* Ignore indirect symbols. These are added by the versioning code. */
2170 /* Ignore this if we won't export it. */
2178 {
2180 {
2183 }
2184 }
2187 }
2188 \f
2189 /* Look through the symbols which are defined in other shared
2190 libraries and referenced here. Update the list of version
2191 dependencies. This will be put into the .gnu.version_r section.
2192 This function is called via elf_link_hash_traverse. */
2194 static bfd_boolean
2197 {
2203 /* We only care about symbols defined in shared objects with version
2204 information. */
2213 /* See if we already know about this version. */
2217 {
2226 }
2228 /* This is a new version. Add it to tree we are building. */
2231 {
2235 {
2238 }
2243 }
2248 {
2251 }
2253 /* Note that we are copying a string pointer here, and testing it
2254 above. If bfd_elf_string_from_elf_section is ever changed to
2255 discard the string data when low in memory, this will have to be
2256 fixed. */
2270 }
2272 /* Return TRUE and set *HIDE to TRUE if the versioned symbol is
2273 hidden. Set *T_P to NULL if there is no match. */
2275 static bfd_boolean
2281 {
2284 /* Look for the version. If we find it, it is no longer weak. */
2286 {
2288 {
2309 /* See if there is anything to force this symbol to
2310 local scope. */
2312 {
2318 }
2322 }
2323 }
2328 }
2330 /* Return TRUE if the symbol H is hidden by version script. */
2332 bfd_boolean
2335 {
2341 /* Version script only hides symbols defined in regular objects. */
2347 {
2357 {
2361 }
2362 }
2364 /* If we don't have a version for this symbol, see if we can find
2365 something. */
2367 {
2372 {
2375 }
2376 }
2379 }
2381 /* Figure out appropriate versions for all the symbols. We may not
2382 have the version number script until we have read all of the input
2383 files, so until that point we don't know which symbols should be
2384 local. This function is called via elf_link_hash_traverse. */
2386 static bfd_boolean
2388 {
2394 bfd_boolean hide;
2399 /* Fix the symbol flags. */
2403 {
2407 }
2411 /* We only need version numbers for symbols defined in regular
2412 objects. */
2414 {
2415 /* Hide symbols defined in discarded input sections. */
2421 }
2426 {
2433 /* If there is no version string, we can just return out. */
2438 {
2441 }
2446 /* If we are building an application, we need to create a
2447 version node for this version. */
2449 {
2453 /* If we aren't going to export this symbol, we don't need
2454 to worry about it. */
2461 {
2464 }
2471 /* Don't count anonymous version tag. */
2484 }
2486 {
2487 /* We could not find the version for a symbol when
2488 generating a shared archive. Return an error. */
2489 _bfd_error_handler
2490 /* xgettext:c-format */
2496 }
2497 }
2499 /* If we don't have a version for this symbol, see if we can find
2500 something. */
2504 {
2510 }
2513 }
2514 \f
2515 /* Read and swap the relocs from the section indicated by SHDR. This
2516 may be either a REL or a RELA section. The relocations are
2517 translated into RELA relocations and stored in INTERNAL_RELOCS,
2518 which should have already been allocated to contain enough space.
2519 The EXTERNAL_RELOCS are a buffer where the external form of the
2520 relocations should be stored.
2522 Returns FALSE if something goes wrong. */
2524 static bfd_boolean
2530 {
2539 /* Position ourselves at the start of the section. */
2543 /* Read the relocations. */
2552 /* Convert the external relocations to the internal format. */
2557 else
2558 {
2561 }
2564 /* Setting erelaend like this and comparing with <= handles case of
2565 a fuzzed object with sh_size not a multiple of sh_entsize. */
2569 {
2570 bfd_vma r_symndx;
2577 {
2579 {
2580 _bfd_error_handler
2581 /* xgettext:c-format */
2588 }
2589 }
2591 {
2592 _bfd_error_handler
2593 /* xgettext:c-format */
2601 }
2604 }
2607 }
2609 /* Read and swap the relocs for a section O. They may have been
2610 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2611 not NULL, they are used as buffers to read into. They are known to
2612 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2613 the return value is allocated using either malloc or bfd_alloc,
2614 according to the KEEP_MEMORY argument. If O has two relocation
2615 sections (both REL and RELA relocations), then the REL_HDR
2616 relocations will appear first in INTERNAL_RELOCS, followed by the
2617 RELA_HDR relocations. */
2619 Elf_Internal_Rela *
2624 bfd_boolean keep_memory)
2625 {
2639 {
2640 bfd_size_type size;
2645 else
2649 }
2652 {
2664 }
2668 {
2670 external_relocs,
2671 internal_relocs))
2677 }
2681 external_relocs,
2682 internal_rela_relocs)))
2685 /* Cache the results for next time, if we can. */
2691 /* Don't free alloc2, since if it was allocated we are passing it
2692 back (under the name of internal_relocs). */
2696 error_return:
2699 {
2702 else
2704 }
2706 }
2708 /* Compute the size of, and allocate space for, REL_HDR which is the
2709 section header for a section containing relocations for O. */
2711 static bfd_boolean
2714 {
2717 /* That allows us to calculate the size of the section. */
2720 /* The contents field must last into write_object_contents, so we
2721 allocate it with bfd_alloc rather than malloc. Also since we
2722 cannot be sure that the contents will actually be filled in,
2723 we zero the allocated space. */
2729 {
2738 }
2741 }
2743 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
2744 originated from the section given by INPUT_REL_HDR) to the
2745 OUTPUT_BFD. */
2747 bfd_boolean
2753 ATTRIBUTE_UNUSED)
2754 {
2769 {
2772 }
2775 {
2778 }
2779 else
2780 {
2781 _bfd_error_handler
2782 /* xgettext:c-format */
2787 }
2795 {
2799 }
2801 /* Bump the counter, so that we know where to add the next set of
2802 relocations. */
2806 }
2807 \f
2808 /* Make weak undefined symbols in PIE dynamic. */
2810 bfd_boolean
2813 {
2820 }
2822 /* Fix up the flags for a symbol. This handles various cases which
2823 can only be fixed after all the input files are seen. This is
2824 currently called by both adjust_dynamic_symbol and
2825 assign_sym_version, which is unnecessary but perhaps more robust in
2826 the face of future changes. */
2828 static bfd_boolean
2831 {
2834 /* If this symbol was mentioned in a non-ELF file, try to set
2835 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
2836 permit a non-ELF file to correctly refer to a symbol defined in
2837 an ELF dynamic object. */
2839 {
2845 {
2848 }
2849 else
2850 {
2854 {
2857 }
2858 else
2860 }
2865 {
2867 {
2870 }
2871 }
2872 }
2873 else
2874 {
2875 /* Unfortunately, NON_ELF is only correct if the symbol
2876 was first seen in a non-ELF file. Fortunately, if the symbol
2877 was first seen in an ELF file, we're probably OK unless the
2878 symbol was defined in a non-ELF file. Catch that case here.
2879 FIXME: We're still in trouble if the symbol was first seen in
2880 a dynamic object, and then later in a non-ELF regular object. */
2890 }
2892 /* Backend specific symbol fixup. */
2898 /* If this is a final link, and the symbol was defined as a common
2899 symbol in a regular object file, and there was no definition in
2900 any dynamic object, then the linker will have allocated space for
2901 the symbol in a common section but the DEF_REGULAR
2902 flag will not have been set. */
2910 /* Symbols defined in discarded sections shouldn't be dynamic. */
2914 /* If a weak undefined symbol has non-default visibility, we also
2915 hide it from the dynamic linker. */
2920 /* A hidden versioned symbol in executable should be forced local if
2921 it is is locally defined, not referenced by shared library and not
2922 exported. */
2931 /* If -Bsymbolic was used (which means to bind references to global
2932 symbols to the definition within the shared object), and this
2933 symbol was defined in a regular object, then it actually doesn't
2934 need a PLT entry. Likewise, if the symbol has non-default
2935 visibility. If the symbol has hidden or internal visibility, we
2936 will force it local. */
2943 {
2944 bfd_boolean force_local;
2949 }
2951 /* If this is a weak defined symbol in a dynamic object, and we know
2952 the real definition in the dynamic object, copy interesting flags
2953 over to the real definition. */
2955 {
2958 /* If the real definition is defined by a regular object file,
2959 don't do anything special. See the longer description in
2960 _bfd_elf_adjust_dynamic_symbol, below. If the def is not
2961 bfd_link_hash_defined as it was when put on the alias list
2962 then it must have originally been a versioned symbol (for
2963 which a non-versioned indirect symbol is created) and later
2964 a definition for the non-versioned symbol is found. In that
2965 case the indirection is flipped with the versioned symbol
2966 becoming an indirect pointing at the non-versioned symbol.
2967 Thus, not an alias any more. */
2970 {
2974 }
2975 else
2976 {
2983 }
2984 }
2987 }
2989 /* Make the backend pick a good value for a dynamic symbol. This is
2990 called via elf_link_hash_traverse, and also calls itself
2991 recursively. */
2993 static bfd_boolean
2995 {
3003 /* Ignore indirect symbols. These are added by the versioning code. */
3007 /* Fix the symbol flags. */
3015 {
3023 {
3025 {
3028 }
3029 }
3030 }
3032 /* If this symbol does not require a PLT entry, and it is not
3033 defined by a dynamic object, or is not referenced by a regular
3034 object, ignore it. We do have to handle a weak defined symbol,
3035 even if no regular object refers to it, if we decided to add it
3036 to the dynamic symbol table. FIXME: Do we normally need to worry
3037 about symbols which are defined by one dynamic object and
3038 referenced by another one? */
3045 {
3048 }
3050 /* If we've already adjusted this symbol, don't do it again. This
3051 can happen via a recursive call. */
3055 /* Don't look at this symbol again. Note that we must set this
3056 after checking the above conditions, because we may look at a
3057 symbol once, decide not to do anything, and then get called
3058 recursively later after REF_REGULAR is set below. */
3061 /* If this is a weak definition, and we know a real definition, and
3062 the real symbol is not itself defined by a regular object file,
3063 then get a good value for the real definition. We handle the
3064 real symbol first, for the convenience of the backend routine.
3066 Note that there is a confusing case here. If the real definition
3067 is defined by a regular object file, we don't get the real symbol
3068 from the dynamic object, but we do get the weak symbol. If the
3069 processor backend uses a COPY reloc, then if some routine in the
3070 dynamic object changes the real symbol, we will not see that
3071 change in the corresponding weak symbol. This is the way other
3072 ELF linkers work as well, and seems to be a result of the shared
3073 library model.
3075 I will clarify this issue. Most SVR4 shared libraries define the
3076 variable _timezone and define timezone as a weak synonym. The
3077 tzset call changes _timezone. If you write
3078 extern int timezone;
3079 int _timezone = 5;
3080 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3081 you might expect that, since timezone is a synonym for _timezone,
3082 the same number will print both times. However, if the processor
3083 backend uses a COPY reloc, then actually timezone will be copied
3084 into your process image, and, since you define _timezone
3085 yourself, _timezone will not. Thus timezone and _timezone will
3086 wind up at different memory locations. The tzset call will set
3087 _timezone, leaving timezone unchanged. */
3090 {
3093 /* If we get to this point, there is an implicit reference to
3094 the alias by a regular object file via the weak symbol H. */
3097 /* Ensure that the backend adjust_dynamic_symbol function sees
3098 the strong alias before H by recursively calling ourselves. */
3101 }
3103 /* If a symbol has no type and no size and does not require a PLT
3104 entry, then we are probably about to do the wrong thing here: we
3105 are probably going to create a COPY reloc for an empty object.
3106 This case can arise when a shared object is built with assembly
3107 code, and the assembly code fails to set the symbol type. */
3111 _bfd_error_handler
3116 {
3119 }
3122 }
3124 /* Adjust the dynamic symbol, H, for copy in the dynamic bss section,
3125 DYNBSS. */
3127 bfd_boolean
3131 {
3133 bfd_vma mask;
3136 /* The section alignment of the definition is the maximum alignment
3137 requirement of symbols defined in the section. Since we don't
3138 know the symbol alignment requirement, we start with the
3139 maximum alignment and check low bits of the symbol address
3140 for the minimum alignment. */
3144 {
3147 }
3150 {
3151 /* Adjust the section alignment if needed. */
3154 }
3156 /* We make sure that the symbol will be aligned properly. */
3159 /* Define the symbol as being at this point in DYNBSS. */
3163 /* Increment the size of DYNBSS to make room for the symbol. */
3166 /* No error if extern_protected_data is true. */
3176 }
3178 /* Adjust all external symbols pointing into SEC_MERGE sections
3179 to reflect the object merging within the sections. */
3181 static bfd_boolean
3183 {
3190 {
3198 }
3201 }
3203 /* Returns false if the symbol referred to by H should be considered
3204 to resolve local to the current module, and true if it should be
3205 considered to bind dynamically. */
3207 bfd_boolean
3210 bfd_boolean not_local_protected)
3211 {
3212 bfd_boolean binding_stays_local_p;
3223 /* If it was forced local, then clearly it's not dynamic. */
3229 /* Identify the cases where name binding rules say that a
3230 visible symbol resolves locally. */
3235 {
3247 /* Proper resolution for function pointer equality may require
3248 that these symbols perhaps be resolved dynamically, even though
3249 we should be resolving them to the current module. */
3256 }
3258 /* If it isn't defined locally, then clearly it's dynamic. */
3262 /* Otherwise, the symbol is dynamic if binding rules don't tell
3263 us that it remains local. */
3265 }
3267 /* Return true if the symbol referred to by H should be considered
3268 to resolve local to the current module, and false otherwise. Differs
3269 from (the inverse of) _bfd_elf_dynamic_symbol_p in the treatment of
3270 undefined symbols. The two functions are virtually identical except
3271 for the place where dynindx == -1 is tested. If that test is true,
3272 _bfd_elf_dynamic_symbol_p will say the symbol is local, while
3273 _bfd_elf_symbol_refs_local_p will say the symbol is local only for
3274 defined symbols.
3275 It might seem that _bfd_elf_dynamic_symbol_p could be rewritten as
3276 !_bfd_elf_symbol_refs_local_p, except that targets differ in their
3277 treatment of undefined weak symbols. For those that do not make
3278 undefined weak symbols dynamic, both functions may return false. */
3280 bfd_boolean
3283 bfd_boolean local_protected)
3284 {
3288 /* If it's a local sym, of course we resolve locally. */
3292 /* STV_HIDDEN or STV_INTERNAL ones must be local. */
3297 /* Forced local symbols resolve locally. */
3301 /* Common symbols that become definitions don't get the DEF_REGULAR
3302 flag set, so test it first, and don't bail out. */
3305 /* If we don't have a definition in a regular file, then we can't
3306 resolve locally. The sym is either undefined or dynamic. */
3310 /* Non-dynamic symbols resolve locally. */
3314 /* At this point, we know the symbol is defined and dynamic. In an
3315 executable it must resolve locally, likewise when building symbolic
3316 shared libraries. */
3320 /* Now deal with defined dynamic symbols in shared libraries. Ones
3321 with default visibility might not resolve locally. */
3331 /* If extern_protected_data is false, STV_PROTECTED non-function
3332 symbols are local. */
3339 /* Function pointer equality tests may require that STV_PROTECTED
3340 symbols be treated as dynamic symbols. If the address of a
3341 function not defined in an executable is set to that function's
3342 plt entry in the executable, then the address of the function in
3343 a shared library must also be the plt entry in the executable. */
3345 }
3347 /* Caches some TLS segment info, and ensures that the TLS segment vma is
3348 aligned. Returns the first TLS output section. */
3352 {
3367 /* Ensure the alignment of the first section (usually .tdata) is the largest
3368 alignment, so that the tls segment starts aligned. */
3373 }
3375 /* Return TRUE iff this is a non-common, definition of a non-function symbol. */
3376 static bfd_boolean
3379 {
3382 /* Local symbols do not count, but target specific ones might. */
3388 /* Function symbols do not count. */
3392 /* If the section is undefined, then so is the symbol. */
3396 /* If the symbol is defined in the common section, then
3397 it is a common definition and so does not count. */
3401 /* If the symbol is in a target specific section then we
3402 must rely upon the backend to tell us what it is. */
3404 /* FIXME - this function is not coded yet:
3406 return _bfd_is_global_symbol_definition (abfd, sym);
3408 Instead for now assume that the definition is not global,
3409 Even if this is wrong, at least the linker will behave
3410 in the same way that it used to do. */
3414 }
3416 /* Search the symbol table of the archive element of the archive ABFD
3417 whose archive map contains a mention of SYMDEF, and determine if
3418 the symbol is defined in this element. */
3419 static bfd_boolean
3421 {
3429 bfd_boolean result;
3438 /* Select the appropriate symbol table. If we don't know if the
3439 object file is an IR object, give linker LTO plugin a chance to
3440 get the correct symbol table. */
3442 #if BFD_SUPPORTS_PLUGINS
3445 #endif
3446 )
3447 {
3448 /* Use the IR symbol table if the object has been claimed by
3449 plugin. */
3452 }
3455 else
3460 /* The sh_info field of the symtab header tells us where the
3461 external symbols start. We don't care about the local symbols. */
3463 {
3466 }
3467 else
3468 {
3471 }
3476 /* Read in the symbol table. */
3482 /* Scan the symbol table looking for SYMDEF. */
3485 {
3494 {
3497 }
3498 }
3503 }
3504 \f
3505 /* Add an entry to the .dynamic table. */
3507 bfd_boolean
3509 bfd_vma tag,
3510 bfd_vma val)
3511 {
3515 bfd_size_type newsize;
3517 Elf_Internal_Dyn dyn;
3543 }
3545 /* Strip zero-sized dynamic sections. */
3547 bfd_boolean
3549 {
3554 Elf_Internal_Dyn dyn;
3557 bfd_boolean strip_zero_sized;
3558 bfd_boolean strip_zero_sized_plt;
3580 /* Strip zero-sized dynamic sections. */
3589 {
3598 {
3601 }
3602 else
3606 }
3607 else
3614 {
3618 {
3624 /* Strip DT_PLTRELSZ, DT_JMPREL and DT_PLTREL entries if
3625 the procedure linkage table (the .plt section) has been
3626 removed. */
3630 }
3631 }
3634 {
3635 /* Regenerate program headers. */
3638 }
3641 }
3643 /* Add a DT_NEEDED entry for this dynamic object. Returns -1 on error,
3644 1 if a DT_NEEDED tag already exists, and 0 on success. */
3646 int
3648 {
3663 {
3674 {
3675 Elf_Internal_Dyn dyn;
3680 {
3683 }
3684 }
3685 }
3694 }
3696 /* Return true if SONAME is on the needed list between NEEDED and STOP
3697 (or the end of list if STOP is NULL), and needed by a library that
3698 will be loaded. */
3700 static bfd_boolean
3704 {
3709 /* If needed by a library that itself is not directly
3710 needed, recursively check whether that library is
3711 indirectly needed. Since we add DT_NEEDED entries to
3712 the end of the list, library dependencies appear after
3713 the library. Therefore search prior to the current
3714 LOOK, preventing possible infinite recursion. */
3719 }
3721 /* Sort symbol by value, section, size, and type. */
3722 static int
3724 {
3727 bfd_signed_vma vdiff;
3742 /* Sort so that sized symbols are selected over zero size symbols. */
3747 /* Sort so that STT_OBJECT is selected over STT_NOTYPE. */
3751 /* If symbols are properly sized and typed, and multiple strong
3752 aliases are not defined in a shared library by the user we
3753 shouldn't get here. Unfortunately linker script symbols like
3754 __bss_start sometimes match a user symbol defined at the start of
3755 .bss without proper size and type. We'd like to preference the
3756 user symbol over reserved system symbols. Sort on leading
3757 underscores. */
3761 {
3766 }
3772 /* Final sort on name selects user symbols like '_u' over reserved
3773 system symbols like '_Z' and also will avoid qsort instability. */
3775 }
3777 /* This function is used to adjust offsets into .dynstr for
3778 dynamic symbols. This is called via elf_link_hash_traverse. */
3780 static bfd_boolean
3782 {
3788 }
3790 /* Assign string offsets in .dynstr, update all structures referencing
3791 them. */
3793 static bfd_boolean
3795 {
3801 bfd_size_type size;
3808 /* Allow the linker to examine the dynsymtab now it's fully populated. */
3817 /* Update all .dynamic entries referencing .dynstr strings. */
3821 {
3822 Elf_Internal_Dyn dyn;
3826 {
3842 }
3844 }
3846 /* Now update local dynamic symbols. */
3851 /* And the rest of dynamic symbols. */
3854 /* Adjust version definitions. */
3856 {
3860 Elf_Internal_Verdef def;
3861 Elf_Internal_Verdaux defaux;
3865 do
3866 {
3873 {
3881 }
3882 }
3884 }
3886 /* Adjust version references. */
3888 {
3892 Elf_Internal_Verneed need;
3893 Elf_Internal_Vernaux needaux;
3897 do
3898 {
3906 {
3915 }
3916 }
3918 }
3921 }
3922 \f
3923 /* Return TRUE iff relocations for INPUT are compatible with OUTPUT.
3924 The default is to only match when the INPUT and OUTPUT are exactly
3925 the same target. */
3927 bfd_boolean
3930 {
3932 }
3934 /* Return TRUE iff relocations for INPUT are compatible with OUTPUT.
3935 This version is used when different targets for the same architecture
3936 are virtually identical. */
3938 bfd_boolean
3941 {
3953 /* If both backends are using this function, deem them compatible. */
3955 }
3957 /* Make a special call to the linker "notice" function to tell it that
3958 we are about to handle an as-needed lib, or have finished
3959 processing the lib. */
3961 bfd_boolean
3965 {
3967 }
3969 /* Check relocations an ELF object file. */
3971 bfd_boolean
3973 {
3977 /* If this object is the same format as the output object, and it is
3978 not a shared library, then let the backend look through the
3979 relocs.
3981 This is required to build global offset table entries and to
3982 arrange for dynamic relocs. It is not required for the
3983 particular common case of linking non PIC code, even when linking
3984 against shared libraries, but unfortunately there is no way of
3985 knowing whether an object file has been compiled PIC or not.
3986 Looking through the relocs is not particularly time consuming.
3987 The problem is that we must either (1) keep the relocs in memory,
3988 which causes the linker to require additional runtime memory or
3989 (2) read the relocs twice from the input file, which wastes time.
3990 This would be a good case for using mmap.
3992 I have no idea how to handle linking PIC code into a file of a
3993 different format. It probably can't be done. */
3999 {
4003 {
4005 bfd_boolean ok;
4007 /* Don't check relocations in excluded sections. Don't do
4008 anything special with non-loaded, non-alloced sections.
4009 In particular, any relocs in such sections should not
4010 affect GOT and PLT reference counting (ie. we don't
4011 allow them to create GOT or PLT entries), there's no
4012 possibility or desire to optimize TLS relocs, and
4013 there's not much point in propagating relocs to shared
4014 libs that the dynamic linker won't relocate. */
4036 }
4037 }
4040 }
4042 /* Add symbols from an ELF object file to the linker hash table. */
4044 static bfd_boolean
4046 {
4053 bfd_boolean dynamic;
4064 bfd_boolean add_needed;
4077 bfd_boolean just_syms;
4084 else
4085 {
4088 /* You can't use -r against a dynamic object. Also, there's no
4089 hope of using a dynamic object which does not exactly match
4090 the format of the output file. */
4094 {
4097 else
4100 }
4101 }
4110 _bfd_error_handler
4111 /* xgettext:c-format */
4115 /* As a GNU extension, any input sections which are named
4116 .gnu.warning.SYMBOL are treated as warning symbols for the given
4117 symbol. This differs from .gnu.warning sections, which generate
4118 warnings when they are included in an output file. */
4119 /* PR 12761: Also generate this warning when building shared libraries. */
4121 {
4126 {
4128 bfd_size_type sz;
4132 /* If this is a shared object, then look up the symbol
4133 in the hash table. If it is there, and it is already
4134 been defined, then we will not be using the entry
4135 from this shared object, so we don't need to warn.
4136 FIXME: If we see the definition in a regular object
4137 later on, we will warn, but we shouldn't. The only
4138 fix is to keep track of what warnings we are supposed
4139 to emit, and then handle them all at the end of the
4140 link. */
4142 {
4147 /* FIXME: What about bfd_link_hash_common? */
4152 }
4170 {
4171 /* Clobber the section size so that the warning does
4172 not get copied into the output file. */
4175 /* Also set SEC_EXCLUDE, so that symbols defined in
4176 the warning section don't get copied to the output. */
4178 }
4179 }
4180 }
4187 {
4188 /* If we are creating a shared library, create all the dynamic
4189 sections immediately. We need to attach them to something,
4190 so we attach them to this BFD, provided it is the right
4191 format and is not from ld --just-symbols. Always create the
4192 dynamic sections for -E/--dynamic-list. FIXME: If there
4193 are no input BFD's of the same format as the output, we can't
4194 make a shared library. */
4203 {
4206 }
4207 }
4210 else
4211 {
4218 /* ld --just-symbols and dynamic objects don't mix very well.
4219 ld shouldn't allow it. */
4223 /* If this dynamic lib was specified on the command line with
4224 --as-needed in effect, then we don't want to add a DT_NEEDED
4225 tag unless the lib is actually used. Similary for libs brought
4226 in by another lib's DT_NEEDED. When --no-add-needed is used
4227 on a dynamic lib, we don't want to add a DT_NEEDED entry for
4228 any dynamic library in DT_NEEDED tags in the dynamic lib at
4229 all. */
4236 {
4243 {
4244 error_free_dyn:
4247 }
4257 {
4258 Elf_Internal_Dyn dyn;
4262 {
4267 }
4269 {
4288 ;
4290 }
4292 {
4313 ;
4315 }
4316 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
4318 {
4339 ;
4341 }
4343 {
4346 }
4347 }
4350 }
4352 /* DT_RUNPATH overrides DT_RPATH. Do _NOT_ bfd_release, as that
4353 frees all more recently bfd_alloc'd blocks as well. */
4358 {
4361 ;
4363 }
4365 /* If we have a PT_GNU_RELRO program header, mark as read-only
4366 all sections contained fully therein. This makes relro
4367 shared library sections appear as they will at run-time. */
4371 {
4373 {
4380 }
4382 }
4384 /* We do not want to include any of the sections in a dynamic
4385 object in the output file. We hack by simply clobbering the
4386 list of sections in the BFD. This could be handled more
4387 cleanly by, say, a new section flag; the existing
4388 SEC_NEVER_LOAD flag is not the one we want, because that one
4389 still implies that the section takes up space in the output
4390 file. */
4393 /* Find the name to use in a DT_NEEDED entry that refers to this
4394 object. If the object has a DT_SONAME entry, we use it.
4395 Otherwise, if the generic linker stuck something in
4396 elf_dt_name, we use that. Otherwise, we just use the file
4397 name. */
4399 {
4403 }
4405 /* Save the SONAME because sometimes the linker emulation code
4406 will need to know it. */
4409 /* If we have already included this dynamic object in the
4410 link, just ignore it. There is no reason to include a
4411 particular dynamic object more than once. */
4415 {
4418 }
4420 /* Create dynamic sections for backends that require that be done
4421 before setup_gnu_properties. */
4426 /* Save the DT_AUDIT entry for the linker emulation code. */
4428 }
4430 /* If this is a dynamic object, we always link against the .dynsym
4431 symbol table, not the .symtab symbol table. The dynamic linker
4432 will only see the .dynsym symbol table, so there is no reason to
4433 look at .symtab for a dynamic object. */
4437 else
4442 /* The sh_info field of the symtab header tells us where the
4443 external symbols start. We don't care about the local symbols at
4444 this point. */
4446 {
4449 }
4450 else
4451 {
4454 }
4458 {
4465 {
4466 /* We store a pointer to the hash table entry for each
4467 external symbol. */
4473 }
4474 }
4477 {
4478 /* Read in any version definitions. */
4483 /* Read in the symbol versions, but don't bother to convert them
4484 to internal format. */
4486 {
4497 }
4498 }
4500 /* If we are loading an as-needed shared lib, save the symbol table
4501 state before we start adding symbols. If the lib turns out
4502 to be unneeded, restore the state. */
4504 {
4509 {
4514 {
4518 {
4521 }
4524 }
4525 }
4532 /* Remember the current objalloc pointer, so that all mem for
4533 symbols added can later be reclaimed. */
4538 /* Make a special call to the linker "notice" function to
4539 tell it that we are about to handle an as-needed lib. */
4543 /* Clone the symbol table. Remember some pointers into the
4544 symbol table, and dynamic symbol count. */
4554 {
4558 }
4561 {
4566 {
4571 {
4575 }
4577 {
4580 }
4581 }
4582 }
4583 }
4590 else
4591 {
4592 /* xgettext:c-format */
4598 }
4602 {
4603 _bfd_error_handler
4605 }
4610 {
4612 bfd_vma value;
4614 flagword flags;
4618 bfd_boolean definition;
4619 bfd_boolean size_change_ok;
4620 bfd_boolean type_change_ok;
4621 bfd_boolean new_weak;
4622 bfd_boolean old_weak;
4624 bfd_boolean common;
4625 bfd_boolean discarded;
4629 bfd_boolean matched;
4638 {
4639 /* Treat common symbol as undefined for --no-define-common. */
4642 }
4647 {
4649 /* This should be impossible, since ELF requires that all
4650 global symbols follow all local symbols, and that sh_info
4651 point to the first global symbol. Unfortunately, Irix 5
4652 screws this up. */
4656 /* If we aren't prepared to handle locals within the globals
4657 then we'll likely segfault on a NULL symbol hash if the
4658 symbol is ever referenced in relocations. */
4666 /* Dynamic object relocations are not processed by ld, so
4667 ld won't run into the problem mentioned above. */
4687 /* Leave it up to the processor backend. */
4689 }
4696 {
4698 /* What ELF calls the size we call the value. What ELF
4699 calls the value we call the alignment. */
4701 }
4702 else
4703 {
4708 {
4709 /* Symbols from discarded section are undefined. We keep
4710 its visibility. */
4714 }
4717 }
4726 {
4730 {
4736 }
4738 }
4742 {
4746 {
4752 }
4754 }
4756 {
4761 /* The hook function sets the name to NULL if this symbol
4762 should be skipped for some reason. */
4765 }
4767 /* Sanity check that all possibilities were handled. */
4771 /* Silently discard TLS symbols from --just-syms. There's
4772 no way to combine a static TLS block with a new TLS block
4773 for this executable. */
4781 else
4793 {
4794 Elf_Internal_Versym iver;
4796 bfd_boolean skip;
4799 {
4801 /* Use the default symbol version created earlier. */
4803 else
4805 }
4807 {
4808 /* xgettext:c-format */
4810 abfd);
4813 }
4814 else
4819 /* If this is a hidden symbol, or if it is not version
4820 1, we append the version name to the symbol name.
4821 However, we do not modify a non-hidden absolute symbol
4822 if it is not a function, because it might be the version
4823 symbol itself. FIXME: What if it isn't? */
4828 {
4834 {
4838 verstr =
4840 else
4844 {
4845 _bfd_error_handler
4846 /* xgettext:c-format */
4852 }
4853 }
4854 else
4855 {
4856 /* We cannot simply test for the number of
4857 entries in the VERNEED section since the
4858 numbers for the needed versions do not start
4859 at 0. */
4866 {
4870 {
4872 {
4875 }
4876 }
4879 }
4881 {
4882 _bfd_error_handler
4883 /* xgettext:c-format */
4888 }
4889 }
4904 /* If this is a defined non-hidden version symbol,
4905 we add another @ to the name. This indicates the
4906 default version of the symbol. */
4913 }
4915 /* If this symbol has default visibility and the user has
4916 requested we not re-export it, then mark it as hidden. */
4918 && !dynamic
4934 /* Override a definition only if the new symbol matches the
4935 existing one. */
4948 }
4957 /* We need to make sure that indirect symbol dynamic flags are
4958 updated. */
4964 /* Setting the index to -3 tells elf_link_output_extsym that
4965 this symbol is defined in a discarded section. */
4973 && definition
4974 && new_weak
4978 {
4979 /* Keep a list of all weak defined non function symbols from
4980 a dynamic object, using the alias field. Later in this
4981 function we will set the alias field to the correct
4982 value. We only put non-function symbols from dynamic
4983 objects on this list, because that happens to be the only
4984 time we need to know the normal symbol corresponding to a
4985 weak symbol, and the information is time consuming to
4986 figure out. If the alias field is not already NULL,
4987 then this symbol was already defined by some previous
4988 dynamic object, and we will be using that previous
4989 definition anyhow. */
4993 }
4995 /* Set the alignment of a common symbol. */
4998 {
5003 else
5004 {
5005 /* The new symbol is a common symbol in a shared object.
5006 We need to get the alignment from the section. */
5008 }
5011 else
5013 }
5016 {
5017 /* Set a flag in the hash table entry indicating the type of
5018 reference or definition we just found. A dynamic symbol
5019 is one which is referenced or defined by both a regular
5020 object and a shared object. */
5023 /* Plugin symbols aren't normal. Don't set def/ref flags. */
5025 ;
5027 {
5029 {
5033 }
5034 else
5035 {
5038 {
5041 }
5042 }
5043 }
5044 else
5045 {
5047 {
5050 }
5051 else
5052 {
5055 }
5056 }
5058 /* If an indirect symbol has been forced local, don't
5059 make the real symbol dynamic. */
5061 ;
5063 {
5068 }
5069 else
5070 {
5076 }
5078 /* Check to see if we need to add an indirect symbol for
5079 the default name. */
5088 /* Check the alignment when a common symbol is involved. This
5089 can change when a common symbol is overridden by a normal
5090 definition or a common symbol is ignored due to the old
5091 normal definition. We need to make sure the maximum
5092 alignment is maintained. */
5095 {
5109 {
5113 }
5114 else
5118 {
5122 }
5123 else
5124 {
5128 }
5131 {
5132 /* PR binutils/2735 */
5134 _bfd_error_handler
5135 /* xgettext:c-format */
5140 else
5141 _bfd_error_handler
5142 /* xgettext:c-format */
5147 }
5148 }
5150 /* Remember the symbol size if it isn't undefined. */
5154 {
5158 _bfd_error_handler
5159 /* xgettext:c-format */
5166 }
5168 /* If this is a common symbol, then we always want H->SIZE
5169 to be the size of the common symbol. The code just above
5170 won't fix the size if a common symbol becomes larger. We
5171 don't warn about a size change here, because that is
5172 covered by --warn-common. Allow changes between different
5173 function types. */
5181 {
5184 /* Turn an IFUNC symbol from a DSO into a normal FUNC
5185 symbol. */
5191 {
5193 /* xgettext:c-format */
5194 _bfd_error_handler
5200 }
5201 }
5203 /* Merge st_other field. */
5207 /* We don't want to make debug symbol dynamic. */
5213 /* Nor should we make plugin symbols dynamic. */
5218 {
5221 }
5224 {
5227 {
5228 /* Queue non-default versions so that .symver x, x@FOO
5229 aliases can be checked. */
5231 {
5234 nondeflt_vers
5238 }
5240 }
5241 }
5244 {
5249 {
5252 }
5253 }
5255 /* If the symbol already has a dynamic index, but
5256 visibility says it should not be visible, turn it into
5257 a local symbol. */
5259 {
5265 }
5268 && matched
5269 && definition
5270 && ((dynsym
5279 {
5285 /* A symbol from a library loaded via DT_NEEDED of some
5286 other library is referenced by a regular object.
5287 Add a DT_NEEDED entry for it. Issue an error if
5288 --no-add-needed is used and the reference was not
5289 a weak one. */
5292 {
5293 _bfd_error_handler
5294 /* xgettext:c-format */
5299 }
5304 /* Create dynamic sections for backends that require
5305 that be done before setup_gnu_properties. */
5309 }
5310 }
5311 }
5316 && !just_syms
5318 {
5323 else
5326 /* If linker plugin is enabled, set non_ir_ref_regular on symbols
5327 referenced in regular objects so that linker plugin will get
5328 the correct symbol resolution. */
5332 {
5336 /* Don't check relocations in excluded sections. */
5346 NULL,
5354 {
5358 /* Skip local symbols. */
5365 }
5369 }
5370 }
5378 {
5381 /* Restore the symbol table. */
5396 {
5402 {
5403 /* Preserve non_ir_ref_dynamic so that this symbol
5404 will be exported when the dynamic lib becomes needed
5405 in the second pass. */
5415 {
5419 }
5421 {
5424 }
5426 }
5427 }
5429 /* Make a special call to the linker "notice" function to
5430 tell it that symbols added for crefs may need to be removed. */
5436 alloc_mark);
5439 }
5442 {
5447 }
5449 /* Now that all the symbols from this input file are created, if
5450 not performing a relocatable link, handle .symver foo, foo@BAR
5451 such that any relocs against foo become foo@BAR. */
5453 {
5457 {
5482 {
5491 {
5494 }
5495 }
5497 }
5500 }
5502 /* Now set the alias field correctly for all the weak defined
5503 symbols we found. The only way to do this is to search all the
5504 symbols. Since we only need the information for non functions in
5505 dynamic objects, that's the only time we actually put anything on
5506 the list WEAKS. We need this information so that if a regular
5507 object refers to a symbol defined weakly in a dynamic object, the
5508 real symbol in the dynamic object is also put in the dynamic
5509 symbols; we also must arrange for both symbols to point to the
5510 same memory location. We could handle the general case of symbol
5511 aliasing, but a general symbol alias can only be generated in
5512 assembler code, handling it correctly would be very time
5513 consuming, and other ELF linkers don't handle general aliasing
5514 either. */
5516 {
5523 /* Since we have to search the whole symbol list for each weak
5524 defined symbol, search time for N weak defined symbols will be
5525 O(N^2). Binary search will cut it down to O(NlogN). */
5535 {
5540 {
5542 sym_hash++;
5543 sym_count++;
5544 }
5545 }
5548 elf_sort_symbol);
5551 {
5554 bfd_vma vlook;
5571 {
5572 bfd_signed_vma vdiff;
5580 else
5581 {
5587 else
5589 }
5590 }
5592 /* We didn't find a value/section match. */
5596 /* With multiple aliases, or when the weak symbol is already
5597 strongly defined, we have multiple matching symbols and
5598 the binary search above may land on any of them. Step
5599 one past the matching symbol(s). */
5601 {
5606 }
5608 /* Now look back over the aliases. Since we sorted by size
5609 as well as value and section, we'll choose the one with
5610 the largest size. */
5612 {
5615 /* Stop if value or section doesn't match. */
5620 {
5631 /* If the weak definition is in the list of dynamic
5632 symbols, make sure the real definition is put
5633 there as well. */
5635 {
5637 {
5638 err_free_sym_hash:
5641 }
5642 }
5644 /* If the real definition is in the list of dynamic
5645 symbols, make sure the weak definition is put
5646 there as well. If we don't do this, then the
5647 dynamic loader might not merge the entries for the
5648 real definition and the weak definition. */
5650 {
5653 }
5655 }
5656 }
5657 }
5660 }
5666 /* If this is a non-traditional link, try to optimize the handling
5667 of the .stab/.stabstr sections. */
5672 {
5677 {
5687 {
5697 }
5698 }
5699 }
5702 {
5703 /* Add this bfd to the loaded list. */
5712 }
5719 error_free_vers:
5724 error_free_sym:
5726 error_return:
5728 }
5730 /* Return the linker hash table entry of a symbol that might be
5731 satisfied by an archive symbol. Return -1 on error. */
5737 {
5746 /* If this is a default version (the name contains @@), look up the
5747 symbol again with only one `@' as well as without the version.
5748 The effect is that references to the symbol with and without the
5749 version will be matched by the default symbol in the archive. */
5755 /* First check with only one `@'. */
5767 {
5768 /* We also need to check references to the symbol without the
5769 version. */
5773 }
5777 }
5779 /* Add symbols from an ELF archive file to the linker hash table. We
5780 don't use _bfd_generic_link_add_archive_symbols because we need to
5781 handle versioned symbols.
5783 Fortunately, ELF archive handling is simpler than that done by
5784 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
5785 oddities. In ELF, if we find a symbol in the archive map, and the
5786 symbol is currently undefined, we know that we must pull in that
5787 object file.
5789 Unfortunately, we do have to make multiple passes over the symbol
5790 table until nothing further is resolved. */
5792 static bfd_boolean
5794 {
5795 symindex c;
5798 bfd_boolean loop;
5805 {
5806 /* An empty archive is a special case. */
5811 }
5813 /* Keep track of all symbols we know to be already defined, and all
5814 files we know to be already included. This is to speed up the
5815 second and subsequent passes. */
5828 do
5829 {
5830 file_ptr last;
5831 symindex i;
5841 {
5845 symindex mark;
5850 {
5853 }
5863 {
5864 /* If the archive element has already been loaded then one
5865 of the symbols defined by that element might have been
5866 made undefined due to being in a discarded section. */
5869 }
5871 {
5872 /* We currently have a common symbol. The archive map contains
5873 a reference to this symbol, so we may want to include it. We
5874 only want to include it however, if this archive element
5875 contains a definition of the symbol, not just another common
5876 declaration of it.
5878 Unfortunately some archivers (including GNU ar) will put
5879 declarations of common symbols into their archive maps, as
5880 well as real definitions, so we cannot just go by the archive
5881 map alone. Instead we must read in the element's symbol
5882 table and check that to see what kind of symbol definition
5883 this is. */
5886 }
5887 else
5888 {
5890 /* Symbol must be defined. Don't check it again. */
5893 }
5895 /* We need to include this archive member. */
5911 /* If there are any new undefined symbols, we need to make
5912 another pass through the archive in order to see whether
5913 they can be defined. FIXME: This isn't perfect, because
5914 common symbols wind up on undefs_tail and because an
5915 undefined symbol which is defined later on in this pass
5916 does not require another pass. This isn't a bug, but it
5917 does make the code less efficient than it could be. */
5921 /* Look backward to mark all symbols from this object file
5922 which we have already seen in this pass. */
5924 do
5925 {
5930 }
5933 /* We mark subsequent symbols from this object file as we go
5934 on through the loop. */
5936 }
5937 }
5943 error_return:
5946 }
5948 /* Given an ELF BFD, add symbols to the global hash table as
5949 appropriate. */
5951 bfd_boolean
5953 {
5955 {
5963 }
5964 }
5965 \f
5966 struct hash_codes_info
5967 {
5969 bfd_boolean error;
5970 };
5972 /* This function will be called though elf_link_hash_traverse to store
5973 all hash value of the exported symbols in an array. */
5975 static bfd_boolean
5977 {
5983 /* Ignore indirect symbols. These are added by the versioning code. */
5989 {
5992 {
5995 {
5998 }
6002 }
6003 }
6005 /* Compute the hash value. */
6008 /* Store the found hash value in the array given as the argument. */
6011 /* And store it in the struct so that we can put it in the hash table
6012 later. */
6017 }
6019 struct collect_gnu_hash_codes
6020 {
6031 bfd_size_type xlat;
6038 bfd_boolean error;
6039 };
6041 /* This function will be called though elf_link_hash_traverse to store
6042 all hash value of the exported symbols in an array. */
6044 static bfd_boolean
6046 {
6052 /* Ignore indirect symbols. These are added by the versioning code. */
6056 /* Ignore also local symbols and undefined symbols. */
6062 {
6065 {
6068 {
6071 }
6075 }
6076 }
6078 /* Compute the hash value. */
6081 /* Store the found hash value in the array for compute_bucket_count,
6082 and also for .dynsym reordering purposes. */
6091 }
6093 /* This function will be called though elf_link_hash_traverse to do
6094 final dynamic symbol renumbering in case of .gnu.hash.
6095 If using .MIPS.xhash, invoke record_xhash_symbol to add symbol index
6096 to the translation table. */
6098 static bfd_boolean
6100 {
6105 /* Ignore indirect symbols. */
6109 /* Ignore also local symbols and undefined symbols. */
6111 {
6113 {
6115 {
6118 }
6119 else
6121 }
6123 }
6133 /* Last element terminates the chain. */
6139 {
6143 }
6144 else
6147 }
6149 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
6151 bfd_boolean
6153 {
6160 }
6162 /* Array used to determine the number of hash table buckets to use
6163 based on the number of symbols there are. If there are fewer than
6164 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
6165 fewer than 37 we use 17 buckets, and so forth. We never use more
6166 than 32771 buckets. */
6169 {
6172 };
6174 /* Compute bucket count for hashing table. We do not use a static set
6175 of possible tables sizes anymore. Instead we determine for all
6176 possible reasonable sizes of the table the outcome (i.e., the
6177 number of collisions etc) and choose the best solution. The
6178 weighting functions are not too simple to allow the table to grow
6179 without bounds. Instead one of the weighting factors is the size.
6180 Therefore the result is always a good payoff between few collisions
6181 (= short chain lengths) and table size. */
6182 static size_t
6187 {
6191 /* We have a problem here. The following code to optimize the table
6192 size requires an integer type with more the 32 bits. If
6193 BFD_HOST_U_64_BIT is set we know about such a type. */
6194 #ifdef BFD_HOST_U_64_BIT
6196 {
6204 bfd_size_type amt;
6207 /* Possible optimization parameters: if we have NSYMS symbols we say
6208 that the hashing table must at least have NSYMS/4 and at most
6209 2*NSYMS buckets. */
6215 {
6220 }
6222 /* Create array where we count the collisions in. We must use bfd_malloc
6223 since the size could be large. */
6230 /* Compute the "optimal" size for the hash table. The criteria is a
6231 minimal chain length. The minor criteria is (of course) the size
6232 of the table. */
6234 {
6235 /* Walk through the array of hashcodes and count the collisions. */
6236 BFD_HOST_U_64_BIT max;
6245 /* Determine how often each hash bucket is used. */
6249 /* For the weight function we need some information about the
6250 pagesize on the target. This is information need not be 100%
6251 accurate. Since this information is not available (so far) we
6252 define it here to a reasonable default value. If it is crucial
6253 to have a better value some day simply define this value. */
6254 # ifndef BFD_TARGET_PAGESIZE
6255 # define BFD_TARGET_PAGESIZE (4096)
6256 # endif
6258 /* We in any case need 2 + DYNSYMCOUNT entries for the size values
6259 and the chains. */
6262 # if 1
6263 /* Variant 1: optimize for short chains. We add the squares
6264 of all the chain lengths (which favors many small chain
6265 over a few long chains). */
6269 /* This adds penalties for the overall size of the table. */
6272 # else
6273 /* Variant 2: Optimize a lot more for small table. Here we
6274 also add squares of the size but we also add penalties for
6275 empty slots (the +1 term). */
6279 /* The overall size of the table is considered, but not as
6280 strong as in variant 1, where it is squared. */
6283 # endif
6285 /* Compare with current best results. */
6287 {
6291 }
6292 /* PR 11843: Avoid futile long searches for the best bucket size
6293 when there are a large number of symbols. */
6296 }
6299 }
6300 else
6302 {
6303 /* This is the fallback solution if no 64bit type is available or if we
6304 are not supposed to spend much time on optimizations. We select the
6305 bucket count using a fixed set of numbers. */
6307 {
6311 }
6314 }
6317 }
6319 /* Size any SHT_GROUP section for ld -r. */
6321 bfd_boolean
6323 {
6334 }
6336 /* Set a default stack segment size. The value in INFO wins. If it
6337 is unset, LEGACY_SYMBOL's value is used, and if that symbol is
6338 undefined it is initialized. */
6340 bfd_boolean
6344 bfd_vma default_size)
6345 {
6348 /* Look for legacy symbol. */
6356 {
6357 /* The symbol has no type if specified on the command line. */
6360 /* xgettext:c-format */
6364 /* xgettext:c-format */
6367 else
6369 }
6372 /* If the user didn't set a size, or explicitly inhibit the
6373 size, set it now. */
6376 /* Provide the legacy symbol, if it is referenced. */
6379 {
6392 }
6395 }
6397 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6399 struct elf_gc_sweep_symbol_info
6400 {
6403 bfd_boolean);
6404 };
6406 static bfd_boolean
6408 {
6416 {
6424 }
6427 }
6429 /* Set up the sizes and contents of the ELF dynamic sections. This is
6430 called by the ELF linker emulation before_allocation routine. We
6431 must set the sizes of the sections before the linker sets the
6432 addresses of the various sections. */
6434 bfd_boolean
6444 {
6456 {
6464 /* If we are supposed to export all symbols into the dynamic symbol
6465 table (this is not the normal case), then do so. */
6468 {
6474 _bfd_elf_export_symbol,
6478 }
6481 {
6487 }
6488 else
6491 /* Make all global versions with definition. */
6495 {
6514 /* Check the hidden versioned definition. */
6520 FALSE);
6524 {
6525 /* Check the default versioned definition. */
6530 FALSE);
6531 }
6534 /* Mark this version if there is a definition and it is
6535 not defined in a shared object. */
6541 }
6543 /* Attach all the symbols to their version information. */
6548 _bfd_elf_link_assign_sym_version,
6554 {
6555 /* Check if all global versions have a definition. */
6560 {
6561 _bfd_error_handler
6565 }
6568 {
6571 }
6572 }
6574 /* Set up the version definition section. */
6578 /* We may have created additional version definitions if we are
6579 just linking a regular application. */
6582 /* Skip anonymous version tag. */
6588 else
6589 {
6591 bfd_size_type size;
6593 Elf_Internal_Verdef def;
6594 Elf_Internal_Verdaux defaux;
6602 /* Make space for the base version. */
6607 /* Make space for the default version. */
6609 {
6612 }
6615 {
6618 /* Don't emit base version twice. */
6628 }
6635 /* Fill in the version definition section. */
6644 {
6647 }
6648 else
6649 {
6653 }
6656 {
6658 soname_indx);
6662 }
6663 else
6664 {
6674 }
6681 {
6682 /* Add a symbol representing this version. */
6698 /* Create a duplicate of the base version with the same
6699 aux block, but different flags. */
6706 else
6711 }
6717 {
6721 /* Don't emit the base version twice. */
6729 /* Add a symbol representing this version. */
6757 /* If a basever node is next, it *must* be the last node in
6758 the chain, otherwise Verdef construction breaks. */
6783 {
6785 {
6786 /* This can happen if there was an error in the
6787 version script. */
6789 }
6790 else
6791 {
6795 }
6798 else
6804 }
6805 }
6808 }
6809 }
6814 {
6817 /* Remove the symbols that were in the swept sections from the
6818 dynamic symbol table. */
6823 }
6826 {
6830 /* Work out the size of the version reference section. */
6842 _bfd_elf_link_find_version_dependencies,
6849 else
6850 {
6856 /* Build the version dependency section. */
6862 {
6869 }
6880 {
6896 FALSE);
6903 else
6912 {
6921 else
6927 }
6928 }
6931 }
6932 }
6934 /* Any syms created from now on start with -1 in
6935 got.refcount/offset and plt.refcount/offset. */
6945 /* The backend may have to create some sections regardless of whether
6946 we're dynamic or not. */
6951 /* Determine any GNU_STACK segment requirements, after the backend
6952 has had a chance to set a default segment size. */
6957 else
6958 {
6964 inputobj;
6966 {
6978 {
6982 }
6985 }
6991 }
6994 {
7004 {
7008 }
7011 {
7013 bfd_vma tag;
7016 TRUE);
7023 }
7026 {
7034 }
7037 {
7041 {
7049 }
7050 }
7053 {
7057 TRUE);
7061 }
7064 {
7068 TRUE);
7072 }
7077 /* Find all symbols which were defined in a dynamic object and make
7078 the backend pick a reasonable value for them. */
7080 _bfd_elf_adjust_dynamic_symbol,
7085 /* Add some entries to the .dynamic section. We fill in some of the
7086 values later, in bfd_elf_final_link, but we must add the entries
7087 now so that we know the final size of the .dynamic section. */
7089 /* If there are initialization and/or finalization functions to
7090 call then add the corresponding DT_INIT/DT_FINI entries. */
7099 {
7102 }
7111 {
7114 }
7118 {
7119 /* DT_PREINIT_ARRAY is not allowed in shared library. */
7121 {
7132 {
7133 _bfd_error_handler
7135 sub);
7137 }
7141 }
7146 }
7149 {
7153 }
7156 {
7160 }
7163 /* If .dynstr is excluded from the link, we don't want any of
7164 these tags. Strictly, we should be checking each section
7165 individually; This quick check covers for the case where
7166 someone does a /DISCARD/ : { *(*) }. */
7168 {
7169 bfd_size_type strsize;
7186 }
7187 }
7192 /* The backend must work out the sizes of all the other dynamic
7193 sections. */
7200 {
7202 {
7208 }
7211 {
7214 }
7216 {
7219 }
7222 {
7225 | DF_1_NODELETE
7229 }
7232 {
7238 }
7243 {
7248 }
7249 }
7251 }
7253 /* Find the first non-excluded output section. We'll use its
7254 section symbol for some emitted relocs. */
7255 void
7257 {
7264 {
7268 }
7270 }
7272 /* Find two non-excluded output sections, one for code, one for data.
7273 We'll use their section symbols for some emitted relocs. */
7274 void
7276 {
7280 /* Data first, since setting text_index_section changes
7281 _bfd_elf_omit_section_dynsym_default. */
7286 {
7290 }
7297 {
7300 }
7302 }
7304 #define GNU_HASH_SECTION_NAME(bed) \
7307 bfd_boolean
7309 {
7320 /* Assign dynsym indices. In a shared library we generate a section
7321 symbol for each output section, which come first. Next come all
7322 of the back-end allocated local dynamic syms, followed by the rest
7323 of the global symbols.
7325 This is usually not needed for static binaries, however backends
7326 can request to always do it, e.g. the MIPS backend uses dynamic
7327 symbol counts to lay out GOT, which will be produced in the
7328 presence of GOT relocations even in static binaries (holding fixed
7329 data in that case, to satisfy those relocations). */
7337 {
7344 /* Work out the size of the symbol version section. */
7348 {
7356 }
7358 /* Set the size of the .dynsym and .hash sections. We counted
7359 the number of dynamic symbols in elf_link_add_object_symbols.
7360 We will build the contents of .dynsym and .hash when we build
7361 the final symbol table, because until then we do not know the
7362 correct value to give the symbols. We built the .dynstr
7363 section as we went along in elf_link_add_object_symbols. */
7372 /* The first entry in .dynsym is a dummy symbol. Clear all the
7373 section syms, in case we don't output them all. */
7379 /* Compute the size of the hashing table. As a side effect this
7380 computes the hash values for all the names we export. */
7382 {
7385 bfd_size_type amt;
7390 /* Compute the hash values for all exported symbols. At the same
7391 time store the values in an array so that we could use them for
7392 optimizations. */
7400 /* Put all hash values in HASHCODES. */
7404 {
7407 }
7410 bucketcount
7430 }
7433 {
7437 bfd_size_type amt;
7442 /* Compute the hash values for all exported symbols. At the same
7443 time store the values in an array so that we could use them for
7444 optimizations. */
7455 /* Put all hash values in HASHCODES. */
7459 {
7462 }
7464 bucketcount
7468 {
7471 }
7477 {
7478 /* Empty .gnu.hash or .MIPS.xhash section is special. */
7486 /* 1 empty bucket. */
7488 /* SYMIDX above the special symbol 0. */
7490 /* Just one word for bitmask. */
7492 /* Only hash fn bloom filter. */
7494 /* No hashes are valid - empty bitmask. */
7496 /* No hashes in the only bucket. */
7499 }
7500 else
7501 {
7513 else
7516 {
7520 }
7521 else
7531 {
7534 }
7541 /* Determine how often each hash bucket is used. */
7548 {
7551 }
7562 {
7566 }
7576 {
7579 else
7582 }
7587 /* Renumber dynamic symbols, if populating .gnu.hash section.
7588 If using .MIPS.xhash, populate the translation table. */
7594 {
7596 contents);
7598 }
7602 }
7603 }
7615 }
7618 }
7619 \f
7620 /* Make sure sec_info_type is cleared if sec_info is cleared too. */
7622 static void
7625 {
7628 }
7630 /* Finish SHF_MERGE section merging. */
7632 bfd_boolean
7634 {
7649 {
7659 }
7663 merge_sections_remove_hook);
7665 }
7667 /* Create an entry in an ELF linker hash table. */
7673 {
7674 /* Allocate the structure if it has not already been allocated by a
7675 subclass. */
7677 {
7682 }
7684 /* Call the allocation method of the superclass. */
7687 {
7691 /* Set local fields. */
7698 /* Assume that we have been called by a non-ELF symbol reader.
7699 This flag is then reset by the code which reads an ELF input
7700 file. This ensures that a symbol created by a non-ELF symbol
7701 reader will have the flag set correctly. */
7703 }
7706 }
7708 /* Copy data from an indirect symbol to its direct symbol, hiding the
7709 old indirect symbol. Also used for copying flags to a weakdef. */
7711 void
7715 {
7719 {
7721 {
7725 /* Add reloc counts against the indirect sym to the direct sym
7726 list. Merge any entries against the same section. */
7728 {
7733 {
7738 }
7741 }
7743 }
7747 }
7749 /* Copy down any references that we may have already seen to the
7750 symbol which just became indirect. */
7763 /* Copy over the global and procedure linkage table refcount entries.
7764 These may have been already set up by a check_relocs routine. */
7767 {
7772 }
7775 {
7780 }
7783 {
7790 }
7791 }
7793 void
7796 bfd_boolean force_local)
7797 {
7798 /* STT_GNU_IFUNC symbol must go through PLT. */
7800 {
7803 }
7805 {
7808 {
7813 }
7814 }
7815 }
7817 /* Hide a symbol. */
7819 void
7823 {
7825 {
7834 }
7835 }
7837 /* Initialize an ELF linker hash table. *TABLE has been zeroed by our
7838 caller. */
7840 bfd_boolean
7841 _bfd_elf_link_hash_table_init
7849 {
7850 bfd_boolean ret;
7857 /* The first dynamic symbol is a dummy. */
7867 }
7869 /* Create an ELF linker hash table. */
7873 {
7883 GENERIC_ELF_DATA))
7884 {
7887 }
7891 }
7893 /* Destroy an ELF linker hash table. */
7895 void
7897 {
7905 }
7907 /* This is a hook for the ELF emulation code in the generic linker to
7908 tell the backend linker what file name to use for the DT_NEEDED
7909 entry for a dynamic object. */
7911 void
7913 {
7917 }
7919 int
7921 {
7926 else
7929 }
7931 void
7933 {
7937 }
7939 /* Get the list of DT_NEEDED entries for a link. This is a hook for
7940 the linker ELF emulation code. */
7945 {
7949 }
7951 /* Get the list of DT_RPATH/DT_RUNPATH entries for a link. This is a
7952 hook for the linker ELF emulation code. */
7957 {
7961 }
7963 /* Get the name actually used for a dynamic object for a link. This
7964 is the SONAME entry if there is one. Otherwise, it is the string
7965 passed to bfd_elf_set_dt_needed_name, or it is the filename. */
7969 {
7974 }
7976 /* Get the list of DT_NEEDED entries from a BFD. This is a hook for
7977 the ELF linker emulation code. */
7979 bfd_boolean
7982 {
8016 {
8017 Elf_Internal_Dyn dyn;
8025 {
8044 }
8045 }
8051 error_return:
8054 }
8056 struct elf_symbuf_symbol
8057 {
8061 };
8063 struct elf_symbuf_head
8064 {
8068 };
8070 struct elf_symbol
8071 {
8072 union
8073 {
8079 };
8081 /* Sort references to symbols by ascending section number. */
8083 static int
8085 {
8091 /* Final sort by the address of the sym in the symbuf ensures
8092 a stable sort. */
8096 }
8098 static int
8100 {
8109 }
8113 {
8130 elf_sort_elf_symbol);
8136 shndx_count++;
8142 {
8145 }
8152 {
8154 {
8155 ssymhead++;
8159 }
8164 }
8171 }
8173 /* Check if 2 sections define the same set of local and global
8174 symbols. */
8176 static bfd_boolean
8179 {
8190 bfd_boolean result;
8195 /* Both sections have to be in ELF. */
8225 {
8232 {
8235 }
8236 }
8239 {
8246 {
8249 }
8250 }
8253 {
8254 /* Optimized faster version. */
8261 ssymbuf1++;
8264 {
8270 else
8271 {
8275 }
8276 }
8280 ssymbuf2++;
8283 {
8289 else
8290 {
8294 }
8295 }
8300 symtable1
8302 symtable2
8310 {
8315 }
8320 {
8325 }
8327 /* Sort symbol by name. */
8329 elf_sym_name_compare);
8331 elf_sym_name_compare);
8334 /* Two symbols must have the same binding, type and name. */
8342 }
8351 /* Count definitions in the section. */
8375 /* Sort symbol by name. */
8377 elf_sym_name_compare);
8379 elf_sym_name_compare);
8382 /* Two symbols must have the same binding, type and name. */
8390 done:
8397 }
8399 /* Return TRUE if 2 section types are compatible. */
8401 bfd_boolean
8404 {
8412 }
8413 \f
8414 /* Final phase of ELF linker. */
8416 /* A structure we use to avoid passing large numbers of arguments. */
8418 struct elf_final_link_info
8419 {
8420 /* General link information. */
8422 /* Output BFD. */
8424 /* Symbol string table. */
8426 /* .hash section. */
8428 /* symbol version section (.gnu.version). */
8430 /* Buffer large enough to hold contents of any section. */
8432 /* Buffer large enough to hold external relocs of any section. */
8434 /* Buffer large enough to hold internal relocs of any section. */
8436 /* Buffer large enough to hold external local symbols of any input
8437 BFD. */
8439 /* And a buffer for symbol section indices. */
8441 /* Buffer large enough to hold internal local symbols of any input
8442 BFD. */
8444 /* Array large enough to hold a symbol index for each local symbol
8445 of any input BFD. */
8447 /* Array large enough to hold a section pointer for each local
8448 symbol of any input BFD. */
8450 /* Buffer for SHT_SYMTAB_SHNDX section. */
8452 /* Number of STT_FILE syms seen. */
8454 /* Local symbol hash table. */
8456 };
8458 struct local_hash_entry
8459 {
8460 /* Base hash table entry structure. */
8462 /* Size of the local symbol name. */
8464 /* Number of the duplicated local symbol names. */
8466 };
8468 /* Create an entry in the local symbol hash table. */
8474 {
8476 /* Allocate the structure if it has not already been allocated by a
8477 subclass. */
8479 {
8484 }
8486 /* Call the allocation method of the superclass. */
8489 {
8492 }
8495 }
8497 /* This struct is used to pass information to elf_link_output_extsym. */
8499 struct elf_outext_info
8500 {
8501 bfd_boolean failed;
8502 bfd_boolean localsyms;
8503 bfd_boolean file_sym_done;
8505 };
8508 /* Support for evaluating a complex relocation.
8510 Complex relocations are generalized, self-describing relocations. The
8511 implementation of them consists of two parts: complex symbols, and the
8512 relocations themselves.
8514 The relocations use a reserved elf-wide relocation type code (R_RELC
8515 external / BFD_RELOC_RELC internal) and an encoding of relocation field
8516 information (start bit, end bit, word width, etc) into the addend. This
8517 information is extracted from CGEN-generated operand tables within gas.
8519 Complex symbols are mangled symbols (STT_RELC external / BSF_RELC
8520 internal) representing prefix-notation expressions, including but not
8521 limited to those sorts of expressions normally encoded as addends in the
8522 addend field. The symbol mangling format is:
8524 <node> := <literal>
8525 | <unary-operator> ':' <node>
8526 | <binary-operator> ':' <node> ':' <node>
8527 ;
8529 <literal> := 's' <digits=N> ':' <N character symbol name>
8530 | 'S' <digits=N> ':' <N character section name>
8531 | '#' <hexdigits>
8532 ;
8534 <binary-operator> := as in C
8535 <unary-operator> := as in C, plus "0-" for unambiguous negation. */
8537 static void
8542 bfd_vma val)
8543 {
8549 {
8554 {
8555 /* It is a local symbol: move it to the
8556 "absolute" section and give it a value. */
8560 }
8563 }
8565 /* It is a global symbol: set its link type
8566 to "defined" and give it a value. */
8576 }
8578 static bfd_boolean
8585 {
8595 {
8604 #ifdef DEBUG
8607 #endif
8609 {
8614 #ifdef DEBUG
8617 #endif
8619 }
8620 }
8622 /* Hmm, haven't found it yet. perhaps it is a global. */
8630 {
8634 #ifdef DEBUG
8637 #endif
8639 }
8642 }
8644 /* Looks up NAME in SECTIONS. If found sets RESULT to NAME's address (in
8645 bytes) and returns TRUE, otherwise returns FALSE. Accepts pseudo-section
8646 names like "foo.end" which is the end address of section "foo". */
8648 static bfd_boolean
8653 {
8659 {
8662 }
8664 /* Hmm. still haven't found it. try pseudo-section names. */
8665 /* FIXME: This could be coded more efficiently... */
8667 {
8673 {
8675 {
8679 }
8681 /* Insert more pseudo-section names here, if you like. */
8682 }
8683 }
8686 }
8688 static void
8690 {
8691 /* xgettext:c-format */
8695 }
8697 static bfd_boolean
8702 bfd_vma dot,
8706 {
8709 bfd_vma a;
8710 bfd_vma b;
8720 {
8723 }
8726 {
8739 /* Fall through. */
8746 {
8749 }
8755 /* Is it always possible, with complex symbols, that gas "mis-guessed"
8756 the symbol as a section, or vice-versa. so we're pretty liberal in our
8757 interpretation here; section means "try section first", not "must be a
8758 section", and likewise with symbol. */
8761 {
8765 {
8768 }
8769 }
8770 else
8771 {
8776 {
8779 }
8780 }
8784 /* All that remains are operators. */
8786 #define UNARY_OP(op) \
8787 if (strncmp (sym, #op, strlen (#op)) == 0) \
8788 { \
8789 sym += strlen (#op); \
8791 ++sym; \
8792 *symp = sym; \
8793 if (!eval_symbol (&a, symp, input_bfd, flinfo, dot, \
8794 isymbuf, locsymcount, signed_p)) \
8795 return FALSE; \
8796 if (signed_p) \
8797 *result = op ((bfd_signed_vma) a); \
8798 else \
8799 *result = op a; \
8800 return TRUE; \
8801 }
8803 #define BINARY_OP_HEAD(op) \
8804 if (strncmp (sym, #op, strlen (#op)) == 0) \
8805 { \
8806 sym += strlen (#op); \
8808 ++sym; \
8809 *symp = sym; \
8810 if (!eval_symbol (&a, symp, input_bfd, flinfo, dot, \
8811 isymbuf, locsymcount, signed_p)) \
8812 return FALSE; \
8813 ++*symp; \
8814 if (!eval_symbol (&b, symp, input_bfd, flinfo, dot, \
8815 isymbuf, locsymcount, signed_p)) \
8816 return FALSE;
8817 #define BINARY_OP_TAIL(op) \
8818 if (signed_p) \
8819 *result = ((bfd_signed_vma) a) op ((bfd_signed_vma) b); \
8820 else \
8821 *result = a op b; \
8822 return TRUE; \
8823 }
8824 #define BINARY_OP(op) BINARY_OP_HEAD(op) BINARY_OP_TAIL(op)
8830 {
8833 }
8838 {
8841 }
8854 {
8858 }
8862 {
8866 }
8875 #undef UNARY_OP
8876 #undef BINARY_OP
8880 }
8881 }
8883 static void
8887 bfd_vma x,
8889 {
8893 {
8895 {
8906 /* Computed this way because x >>= 32 is undefined if x is a 32-bit value. */
8910 #ifdef BFD64
8913 /* Computed this way because x >>= 64 is undefined if x is a 64-bit value. */
8917 #endif
8921 }
8922 }
8923 }
8925 static bfd_vma
8930 {
8934 /* Sanity checks. */
8943 {
8946 /* Make sure that we do not perform an undefined shift operation.
8947 We know that size == chunksz so there will only be one iteration
8948 of the loop below. */
8950 }
8951 else
8955 {
8957 {
8967 #ifdef BFD64
8971 #endif
8974 }
8975 }
8977 }
8979 static void
8989 {
8998 }
9000 bfd_reloc_status_type
9005 bfd_vma relocation)
9006 {
9009 bfd_reloc_status_type r;
9010 bfd_size_type octets;
9012 /* Perform this reloc, since it is complex.
9013 (this is not to say that it necessarily refers to a complex
9014 symbol; merely that it is a self-describing CGEN based reloc.
9015 i.e. the addend has the complete reloc information (bit start, end,
9016 word size, etc) encoded within it.). */
9026 else
9032 #ifdef DEBUG
9034 "lsb0? %ld, signed? %ld, trunc? %ld, wordsz %ld, "
9040 #endif
9044 /* Now do an overflow check. */
9046 ? complain_overflow_signed
9049 relocation);
9051 /* Do the deed. */
9054 #ifdef DEBUG
9061 #endif
9064 }
9066 /* Functions to read r_offset from external (target order) reloc
9067 entry. Faster than bfd_getl32 et al, because we let the compiler
9068 know the value is aligned. */
9070 static bfd_vma
9072 {
9073 union aligned32
9074 {
9077 };
9086 }
9088 static bfd_vma
9090 {
9091 union aligned32
9092 {
9095 };
9104 }
9106 #ifdef BFD_HOST_64_BIT
9107 static bfd_vma
9109 {
9110 union aligned64
9111 {
9114 };
9127 }
9129 static bfd_vma
9131 {
9132 union aligned64
9133 {
9136 };
9149 }
9150 #endif
9152 /* When performing a relocatable link, the input relocations are
9153 preserved. But, if they reference global symbols, the indices
9154 referenced must be updated. Update all the relocations found in
9155 RELDATA. */
9157 static bfd_boolean
9161 bfd_boolean sort,
9163 {
9169 bfd_vma r_type_mask;
9175 {
9178 }
9180 {
9183 }
9184 else
9191 {
9194 }
9195 else
9196 {
9199 }
9203 {
9213 {
9214 /* PR 21524: Let the user know if a symbol was removed by garbage collection. */
9215 _bfd_error_handler (_("%pB:%pA: error: relocation references symbol %s which was removed by garbage collection"),
9222 }
9230 }
9236 {
9238 bfd_vma r_off;
9244 {
9249 else
9251 }
9252 else
9253 {
9254 #ifdef BFD_HOST_64_BIT
9259 else
9260 #endif
9262 }
9264 /* Must use a stable sort here. A modified insertion sort,
9265 since the relocs are mostly sorted already. */
9272 /* Ensure the first element is lowest. This acts as a sentinel,
9273 speeding the main loop below. */
9276 {
9279 {
9282 }
9283 }
9285 {
9286 /* Don't just swap *base and *loc as that changes the order
9287 of the original base[0] and base[1] if they happen to
9288 have the same r_offset. */
9293 }
9296 {
9297 /* base to p is sorted, *p is next to insert. */
9299 /* Search the sorted region for location to insert. */
9305 {
9306 /* Chances are there is a run of relocs to insert here,
9307 from one of more input files. Files are not always
9308 linked in order due to the way elf_link_input_bfd is
9309 called. See pr17666. */
9320 {
9324 }
9326 {
9330 }
9331 else
9332 {
9336 }
9338 }
9339 }
9340 /* Hashes are no longer valid. */
9344 }
9346 }
9348 struct elf_link_sort_rela
9349 {
9351 bfd_vma offset;
9352 bfd_vma sym_mask;
9355 /* We use this as an array of size int_rels_per_ext_rel. */
9357 };
9359 /* qsort stability here and for cmp2 is only an issue if multiple
9360 dynamic relocations are emitted at the same address. But targets
9361 that apply a series of dynamic relocations each operating on the
9362 result of the prior relocation can't use -z combreloc as
9363 implemented anyway. Such schemes tend to be broken by sorting on
9364 symbol index. That leaves dynamic NONE relocs as the only other
9365 case where ld might emit multiple relocs at the same address, and
9366 those are only emitted due to target bugs. */
9368 static int
9370 {
9391 }
9393 static int
9395 {
9412 }
9414 static size_t
9416 {
9430 bfd_vma r_sym_mask;
9431 bfd_boolean use_rela;
9433 /* Find a dynamic reloc section. */
9438 {
9441 /* This is just here to stop gcc from complaining.
9442 Its initialization checking code is not perfect. */
9445 /* Both sections are present. Examine the sizes
9446 of the indirect sections to help us choose. */
9449 {
9453 {
9455 /* Section size is divisible by both rel and rela sizes.
9456 It is of no help to us. */
9457 ;
9458 else
9459 {
9460 /* Section size is only divisible by rela. */
9462 {
9465 abfd);
9468 }
9469 else
9470 {
9473 }
9474 }
9475 }
9477 {
9478 /* Section size is only divisible by rel. */
9480 {
9483 abfd);
9486 }
9487 else
9488 {
9491 }
9492 }
9493 else
9494 {
9495 /* The section size is not divisible by either -
9496 something is wrong. */
9501 }
9502 }
9506 {
9510 {
9512 /* Section size is divisible by both rel and rela sizes.
9513 It is of no help to us. */
9514 ;
9515 else
9516 {
9517 /* Section size is only divisible by rela. */
9519 {
9522 abfd);
9525 }
9526 else
9527 {
9530 }
9531 }
9532 }
9534 {
9535 /* Section size is only divisible by rel. */
9537 {
9540 abfd);
9543 }
9544 else
9545 {
9548 }
9549 }
9550 else
9551 {
9552 /* The section size is not divisible by either -
9553 something is wrong. */
9558 }
9559 }
9562 /* Make a guess. */
9564 }
9569 else
9573 {
9578 }
9579 else
9580 {
9585 }
9604 {
9608 }
9612 else
9617 {
9622 {
9623 /* This is a reloc section that is being handled as a normal
9624 section. See bfd_section_from_shdr. We can't combine
9625 relocs in this case. */
9628 }
9634 {
9642 }
9643 }
9648 {
9652 }
9658 {
9663 }
9669 {
9670 /* We have plt relocs in .rela.dyn. */
9676 {
9678 /* Put srelplt link_order last. This is so the output_offset
9679 set in the next loop is correct for DT_JMPREL. */
9683 {
9686 }
9687 else
9692 }
9693 }
9698 {
9706 {
9711 }
9712 }
9717 }
9719 /* Add a symbol to the output symbol string table. */
9721 static int
9727 {
9733 bfd_size_type strtabsize;
9740 {
9744 }
9755 else
9756 {
9757 /* Call _bfd_elf_strtab_offset after _bfd_elf_strtab_finalize
9758 to get the final offset for st_name. */
9761 {
9763 {
9764 /* Keep only one '@' for versioned symbols defined in
9765 shared objects. */
9769 {
9779 }
9780 }
9781 }
9784 {
9787 {
9797 {
9798 /* Append ".COUNT" to duplicated local symbols. */
9804 {
9807 }
9817 }
9820 }
9821 }
9822 elfsym->st_name
9827 }
9832 {
9836 hash_table->strtab
9838 strtabsize);
9841 }
9852 }
9854 /* Swap symbols out to the symbol table and flush the output symbols to
9855 the file. */
9857 static bfd_boolean
9859 {
9866 file_ptr pos;
9867 bfd_boolean ret;
9882 {
9887 {
9890 }
9891 }
9893 /* Now swap out the symbols. */
9895 {
9899 else
9904 /* Inform the linker of the addition of this symbol. */
9916 }
9923 {
9926 }
9927 else
9936 }
9938 /* Return TRUE if the dynamic symbol SYM in ABFD is supported. */
9940 static bfd_boolean
9942 {
9945 {
9946 /* The gABI doesn't support dynamic symbols in output sections
9947 beyond 64k. */
9948 _bfd_error_handler
9949 /* xgettext:c-format */
9954 }
9956 }
9958 /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
9959 allowing an unsatisfied unversioned symbol in the DSO to match a
9960 versioned symbol that would normally require an explicit version.
9961 We also handle the case that a DSO references a hidden symbol
9962 which may be satisfied by a versioned symbol in another DSO. */
9964 static bfd_boolean
9968 {
9975 /* Check indirect symbol. */
9980 {
10002 }
10008 {
10023 /* We check each DSO for a possible hidden versioned definition. */
10032 {
10035 }
10036 else
10037 {
10040 }
10050 /* Read in any version definitions. */
10056 {
10059 }
10064 {
10066 Elf_Internal_Versym iver;
10084 {
10085 /* If we have a non-hidden versioned sym, then it should
10086 have provided a definition for the undefined sym unless
10087 it is defined in a non-shared object and forced local.
10088 */
10090 }
10094 {
10095 /* This is the base or first version. We can use it. */
10099 }
10100 }
10104 }
10107 }
10109 /* Convert ELF common symbol TYPE. */
10111 static int
10113 {
10114 /* Commom symbol can only appear in relocatable link. */
10118 {
10127 }
10129 }
10131 /* Add an external symbol to the symbol table. This is called from
10132 the hash table traversal routine. When generating a shared object,
10133 we go through the symbol table twice. The first time we output
10134 anything that might have been forced to local scope in a version
10135 script. The second time we output the symbols that are still
10136 global symbols. */
10138 static bfd_boolean
10140 {
10144 bfd_boolean strip;
10145 Elf_Internal_Sym sym;
10153 {
10157 }
10159 /* Decide whether to output this symbol in this pass. */
10161 {
10164 }
10165 else
10166 {
10169 }
10174 {
10175 /* If we have an undefined symbol reference here then it must have
10176 come from a shared library that is being linked in. (Undefined
10177 references in regular files have already been handled unless
10178 they are in unreferenced sections which are removed by garbage
10179 collection). */
10182 /* Some symbols may be special in that the fact that they're
10183 undefined can be safely ignored - let backend determine that. */
10187 /* If we are reporting errors for this situation then do so now. */
10193 {
10199 }
10201 /* Strip a global symbol defined in a discarded section. */
10204 }
10206 /* We should also warn if a forced local symbol is referenced from
10207 shared libraries. */
10215 {
10220 /* Check indirect symbol. */
10225 /* xgettext:c-format */
10228 /* xgettext:c-format */
10230 else
10231 /* xgettext:c-format */
10241 }
10243 /* We don't want to output symbols that have never been mentioned by
10244 a regular file, or that we have been told to strip. However, if
10245 h->indx is set to -2, the symbol is used by a reloc and we must
10246 output it. */
10249 ;
10278 /* If we're stripping it, and it's not a dynamic symbol, there's
10279 nothing else to do. However, if it is a forced local symbol or
10280 an ifunc symbol we need to give the backend finish_dynamic_symbol
10281 function a chance to make it dynamic. */
10292 {
10307 {
10310 {
10315 {
10316 _bfd_error_handler
10317 /* xgettext:c-format */
10323 }
10325 /* ELF symbols in relocatable files are section relative,
10326 but in nonrelocatable files they are virtual
10327 addresses. */
10330 {
10333 {
10337 }
10338 }
10339 }
10340 else
10341 {
10346 }
10347 }
10357 /* These symbols are created by symbol versioning. They point
10358 to the decorated version of the name. For example, if the
10359 symbol foo@@GNU_1.2 is the default, which should be used when
10360 foo is used with no version, then we add an indirect symbol
10361 foo which points to foo@@GNU_1.2. We ignore these symbols,
10362 since the indirected symbol is already in the hash table. */
10364 }
10368 {
10376 else
10384 }
10387 {
10389 /* Turn off visibility on local symbol. */
10391 }
10392 /* Set STB_GNU_UNIQUE only if symbol is defined in regular object. */
10398 else
10402 /* Give the processor backend a chance to tweak the symbol value,
10403 and also to finish up anything that needs to be done for this
10404 symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for
10405 forced local syms when non-shared is due to a historical quirk.
10406 STT_GNU_IFUNC symbol must go through PLT. */
10417 {
10420 {
10423 }
10424 }
10426 /* If we are marking the symbol as undefined, and there are no
10427 non-weak references to this symbol from a regular object, then
10428 mark the symbol as weak undefined; if there are non-weak
10429 references, mark the symbol as strong. We can't do this earlier,
10430 because it might not be marked as undefined until the
10431 finish_dynamic_symbol routine gets through with it. */
10436 {
10440 /* Turn an undefined IFUNC symbol into a normal FUNC symbol. */
10446 else
10449 }
10451 /* If this is a symbol defined in a dynamic library, don't use the
10452 symbol size from the dynamic library. Relinking an executable
10453 against a new library may introduce gratuitous changes in the
10454 executable's symbols if we keep the size. */
10460 /* If a non-weak symbol with non-default visibility is not defined
10461 locally, it is a fatal error. */
10467 {
10471 /* xgettext:c-format */
10474 /* xgettext:c-format */
10476 else
10477 /* xgettext:c-format */
10483 }
10485 /* If this symbol should be put in the .dynsym section, then put it
10486 there now. We already know the symbol index. We also fill in
10487 the entry in the .hash section. */
10492 {
10495 /* Since there is no version information in the dynamic string,
10496 if there is no version info in symbol version section, we will
10497 have a run-time problem if not linking executable, referenced
10498 by shared library, or not bound locally. */
10503 {
10507 {
10508 _bfd_error_handler
10509 /* xgettext:c-format */
10514 }
10515 }
10521 {
10524 }
10526 /* Inform the linker of the addition of this symbol. */
10534 {
10537 bfd_vma chain;
10544 hash_entry_size
10550 bucketpos);
10554 }
10557 {
10558 Elf_Internal_Versym iversym;
10562 {
10567 else
10569 }
10570 else
10571 {
10574 else
10578 }
10580 /* Turn on VERSYM_HIDDEN only if the hidden versioned symbol is
10581 defined locally. */
10588 }
10589 }
10591 /* If the symbol is undefined, and we didn't output it to .dynsym,
10592 strip it from .symtab too. Obviously we can't do this for
10593 relocatable output or when needed for --emit-relocs. */
10596 /* PR 22319 Do not strip global undefined symbols marked as being needed. */
10601 /* Also strip others that we couldn't earlier due to dynamic symbol
10602 processing. */
10608 /* Output a FILE symbol so that following locals are not associated
10609 with the wrong input file. We need one for forced local symbols
10610 if we've seen more than one FILE symbol or when we have exactly
10611 one FILE symbol but global symbols are present in a file other
10612 than the one with the FILE symbol. We also need one if linker
10613 defined symbols are present. In practice these conditions are
10614 always met, so just emit the FILE symbol unconditionally. */
10618 {
10619 Elf_Internal_Sym fsym;
10629 }
10635 {
10638 }
10645 }
10647 /* Return TRUE if special handling is done for relocs in SEC against
10648 symbols defined in discarded sections. */
10650 static bfd_boolean
10652 {
10656 {
10663 }
10671 }
10673 /* Return a mask saying how ld should treat relocations in SEC against
10674 symbols defined in discarded sections. If this function returns
10675 COMPLAIN set, ld will issue a warning message. If this function
10676 returns PRETEND set, and the discarded section was link-once and the
10677 same size as the kept link-once section, ld will pretend that the
10678 symbol was actually defined in the kept section. Otherwise ld will
10679 zero the reloc (at least that is the intent, but some cooperation by
10680 the target dependent code is needed, particularly for REL targets). */
10682 unsigned int
10684 {
10695 }
10697 /* Find a match between a section and a member of a section group. */
10702 {
10707 {
10714 }
10717 }
10719 /* Check if the kept section of a discarded section SEC can be used
10720 to replace it. Return the replacement if it is OK. Otherwise return
10721 NULL. */
10723 asection *
10725 {
10730 {
10734 {
10738 else
10739 {
10740 /* Get the real kept section. */
10746 }
10747 }
10749 }
10751 }
10753 /* Link an input file into the linker output file. This function
10754 handles all the sections and relocations of the input file at once.
10755 This is so that we only have to read the local symbols once, and
10756 don't have to keep them in memory. */
10758 static bfd_boolean
10760 {
10776 bfd_size_type address_size;
10777 bfd_vma r_type_mask;
10785 /* If this is a dynamic object, we don't want to do anything here:
10786 we don't want the local symbols, and we don't want the section
10787 contents. */
10793 {
10796 }
10797 else
10798 {
10801 }
10803 /* Enable GNU OSABI features in the output BFD that are used in the input
10804 BFD. */
10813 /* Read the local symbols. */
10816 {
10823 }
10825 /* Find local symbol sections and adjust values of symbols in
10826 SEC_MERGE sections. Write out those local symbols we know are
10827 going into the output file. */
10832 {
10835 Elf_Internal_Sym osym;
10842 {
10844 {
10847 }
10848 }
10856 else
10857 {
10860 {
10861 /* Don't attempt to output symbols with st_shnx in the
10862 reserved range other than SHN_ABS and SHN_COMMON. */
10864 }
10871 }
10875 /* Don't output the first, undefined, symbol. In fact, don't
10876 output any undefined local symbol. */
10881 {
10882 /* We never output section symbols. Instead, we use the
10883 section symbol of the corresponding section in the output
10884 file. */
10886 }
10888 /* If we are stripping all symbols, we don't want to output this
10889 one. */
10893 /* If we are discarding all local symbols, we don't want to
10894 output this one. If we are generating a relocatable output
10895 file, then some of the local symbols may be required by
10896 relocs; we output them below as we discover that they are
10897 needed. */
10901 /* If this symbol is defined in a section which we are
10902 discarding, we don't need to keep it. */
10908 {
10913 }
10921 /* Get the name of the symbol. */
10927 /* See if we are discarding symbols with this name. */
10939 {
10941 /* -flto puts a temp file name here. This means builds
10942 are not reproducible. Discard the symbol. */
10946 }
10948 {
10949 /* In the absence of debug info, bfd_find_nearest_line uses
10950 FILE symbols to determine the source file for local
10951 function symbols. Provide a FILE symbol here if input
10952 files lack such, so that their symbols won't be
10953 associated with a previous input file. It's not the
10954 source file, but the best we can do. */
10964 NULL))
10966 }
10970 /* Adjust the section index for the output file. */
10976 /* ELF symbols in relocatable files are section relative, but
10977 in executable files they are virtual addresses. Note that
10978 this code assumes that all ELF sections have an associated
10979 BFD section with a reasonable value for output_offset; below
10980 we assume that they also have a reasonable value for
10981 output_section. Any special sections must be set up to meet
10982 these requirements. */
10985 {
10988 {
10989 /* STT_TLS symbols are relative to PT_TLS segment base. */
10992 else
10994 STT_NOTYPE);
10995 }
10996 }
11004 }
11007 {
11011 }
11012 else
11013 {
11017 }
11019 /* Relocate the contents of each section. */
11022 {
11026 {
11027 /* This section was omitted from the link. */
11029 }
11033 {
11034 /* Deal with the group signature symbol. */
11043 {
11048 /* Arrange for symbol to be output. */
11051 }
11053 {
11054 /* We'll use the output section target_index. */
11057 }
11058 else
11059 {
11061 {
11062 /* Otherwise output the local symbol now. */
11076 sec);
11084 NULL);
11089 else
11091 }
11094 }
11095 }
11102 {
11103 /* Section was created by _bfd_elf_link_create_dynamic_sections
11104 or somesuch. */
11106 }
11108 /* Get the contents of the section. They have been cached by a
11109 relaxation routine. Note that o is a section in an input
11110 file, so the contents field will not have been set by any of
11111 the routines which work on output files. */
11113 {
11118 {
11121 }
11122 }
11123 else
11124 {
11128 }
11131 {
11137 /* Get the swapped relocs. */
11138 internal_relocs
11145 /* We need to reverse-copy input .ctors/.dtors sections if
11146 they are placed in .init_array/.finit_array for output. */
11155 {
11158 {
11159 _bfd_error_handler
11160 /* xgettext:c-format */
11166 }
11168 }
11174 /* Run through the relocs evaluating complex reloc symbols and
11175 looking for relocs against symbols from discarded sections
11176 or section symbols from removed link-once sections.
11177 Complain about relocs against discarded sections. Zero
11178 relocs against removed link-once sections. */
11183 {
11196 {
11199 /* Badly formatted input files can contain relocs that
11200 reference non-existant symbols. Check here so that
11201 we do not seg fault. */
11203 {
11204 _bfd_error_handler
11205 /* xgettext:c-format */
11211 }
11219 /* If a plugin symbol is referenced from a non-IR file,
11220 mark the symbol as undefined. Note that the
11221 linker may attach linker created dynamic sections
11222 to the plugin bfd. Symbols defined in linker
11223 created sections are not plugin symbols. */
11233 {
11236 }
11244 }
11245 else
11246 {
11253 }
11257 {
11258 bfd_vma val;
11261 #ifdef DEBUG
11271 #endif
11276 /* Symbol evaluated OK. Update to absolute value. */
11280 }
11283 {
11284 /* Complain if the definition comes from a
11285 discarded section. */
11287 {
11291 /* xgettext:c-format */
11296 /* Try to do the best we can to support buggy old
11297 versions of gcc. Pretend that the symbol is
11298 really defined in the kept linkonce section.
11299 FIXME: This is quite broken. Modifying the
11300 symbol here means we will be changing all later
11301 uses of the symbol, not just in this section. */
11303 {
11309 {
11312 }
11313 }
11314 }
11315 }
11316 }
11318 /* Relocate the section by invoking a back end routine.
11320 The back end routine is responsible for adjusting the
11321 section contents as necessary, and (if using Rela relocs
11322 and generating a relocatable output file) adjusting the
11323 reloc addend as necessary.
11325 The back end routine does not have to worry about setting
11326 the reloc address or the reloc symbol index.
11328 The back end routine is given a pointer to the swapped in
11329 internal symbols, and can access the hash table entries
11330 for the external symbols via elf_sym_hashes (input_bfd).
11332 When generating relocatable output, the back end routine
11333 must handle STB_LOCAL/STT_SECTION symbols specially. The
11334 output symbol is going to be a section symbol
11335 corresponding to the output section, which will require
11336 the addend to be adjusted. */
11340 internal_relocs,
11341 isymbuf,
11349 {
11352 bfd_vma last_offset;
11357 bfd_boolean rela_normal;
11364 /* Adjust the reloc addresses and symbol indices. */
11369 /* We start processing the REL relocs, if any. When we reach
11370 IRELAMID in the loop, we switch to the RELA relocs. */
11381 {
11384 Elf_Internal_Sym sym;
11387 {
11388 rel_hash++;
11390 }
11393 {
11397 }
11403 {
11404 /* This is a reloc for a deleted entry or somesuch.
11405 Turn it into an R_*_NONE reloc, at the same
11406 offset as the last reloc. elf_eh_frame.c and
11407 bfd_elf_discard_info rely on reloc offsets
11408 being ordered. */
11413 }
11417 /* Relocs in an executable have to be virtual addresses. */
11430 {
11434 /* This is a reloc against a global symbol. We
11435 have not yet output all the local symbols, so
11436 we do not know the symbol index of any global
11437 symbol. We set the rel_hash entry for this
11438 reloc to point to the global hash table entry
11439 for this symbol. The symbol index is then
11440 set at the end of bfd_elf_final_link. */
11447 /* Setting the index to -2 tells
11448 elf_link_output_extsym that this symbol is
11449 used by a reloc. */
11455 }
11457 /* This is a reloc against a local symbol. */
11463 {
11464 /* I suppose the backend ought to fill in the
11465 section of any STT_SECTION symbol against a
11466 processor specific section. */
11469 ;
11471 {
11474 }
11475 else
11476 {
11479 /* If we have discarded a section, the output
11480 section will be the absolute section. In
11481 case of discarded SEC_MERGE sections, use
11482 the kept section. relocate_section should
11483 have already handled discarded linkonce
11484 sections. */
11488 {
11491 }
11494 {
11497 {
11503 }
11504 }
11505 }
11507 /* Adjust the addend according to where the
11508 section winds up in the output section. */
11511 }
11512 else
11513 {
11515 {
11522 {
11523 /* You can't do ld -r -s. */
11526 }
11528 /* This symbol was skipped earlier, but
11529 since it is needed by a reloc, we
11530 must output it now. */
11532 name = (bfd_elf_string_from_elf_section
11540 osec);
11546 {
11549 {
11553 /* STT_TLS symbols are relative to PT_TLS
11554 segment base. */
11557 else
11558 sym.st_info
11560 STT_NOTYPE);
11561 }
11562 }
11567 NULL);
11572 else
11574 }
11577 }
11581 }
11583 /* Swap out the relocs. */
11586 {
11588 input_rel_hdr,
11589 internal_relocs,
11590 rel_hash_list))
11595 }
11599 {
11601 input_rela_hdr,
11602 internal_relocs,
11603 rela_hash_list))
11605 }
11606 }
11607 }
11609 /* Write out the modified section contents. */
11612 contents))
11613 {
11614 /* Section written out. */
11615 }
11617 {
11631 {
11635 }
11638 {
11643 }
11646 {
11648 {
11655 {
11656 /* Reverse-copy input section to output. */
11657 do
11658 {
11663 offset,
11664 address_size))
11669 }
11671 }
11674 contents,
11677 }
11678 }
11680 }
11681 }
11684 }
11686 /* Generate a reloc when linking an ELF file. This is a reloc
11687 requested by the linker, and does not come from any input file. This
11688 is used to build constructor and destructor tables when linking
11689 with -Ur. */
11691 static bfd_boolean
11696 {
11699 bfd_vma offset;
11700 bfd_vma addend;
11712 {
11715 }
11723 else
11724 {
11727 }
11729 /* Figure out the symbol index. */
11732 {
11736 }
11737 else
11738 {
11741 /* Treat a reloc against a defined symbol as though it were
11742 actually against the section. */
11750 {
11756 /* It seems that we ought to add the symbol value to the
11757 addend here, but in practice it has already been added
11758 because it was passed to constructor_callback. */
11760 }
11762 {
11763 /* Setting the index to -2 tells elf_link_output_extsym that
11764 this symbol is used by a reloc. */
11768 }
11769 else
11770 {
11774 }
11775 }
11777 /* If this is an inplace reloc, we must write the addend into the
11778 object file. */
11780 {
11781 bfd_size_type size;
11782 bfd_reloc_status_type rstat;
11784 bfd_boolean ok;
11786 bfd_size_type octets;
11794 {
11805 else
11811 }
11814 output_section);
11820 }
11822 /* The address of a reloc is relative to the section in a
11823 relocatable file, and is a virtual address in an executable
11824 file. */
11830 {
11834 }
11837 else
11843 {
11846 }
11847 else
11848 {
11852 }
11857 }
11860 /* Compare two sections based on the locations of the sections they are
11861 linked to. Used by elf_fixup_link_order. */
11863 static int
11865 {
11878 /* The only way we should get matching LMAs is when the first of two
11879 sections has zero size. */
11885 /* If they are both zero size then they almost certainly have the same
11886 VMA and thus are not ordered with respect to each other. Test VMA
11887 anyway, and fall back to id to make the result reproducible across
11888 qsort implementations. */
11897 }
11900 /* Looks for sections with SHF_LINK_ORDER set. Rearranges them into the same
11901 order as their linked sections. Returns false if this could not be done
11902 because an output section includes both ordered and unordered
11903 sections. Ideally we'd do this in the linker proper. */
11905 static bfd_boolean
11907 {
11922 {
11924 {
11931 {
11932 seen_linkorder++;
11934 }
11935 else
11936 {
11937 seen_other++;
11939 }
11940 }
11941 else
11942 seen_other++;
11945 {
11947 _bfd_error_handler
11948 /* xgettext:c-format */
11953 else
11954 _bfd_error_handler
11958 }
11959 }
11972 /* Sort the input sections in the order of their linked section. */
11975 /* Change the offsets of the sections. */
11978 {
11979 bfd_vma mask;
11987 }
11991 }
11993 /* Generate an import library in INFO->implib_bfd from symbols in ABFD.
11994 Returns TRUE upon success, FALSE otherwise. */
11996 static bfd_boolean
11998 {
12002 flagword flags;
12018 /* Use flag from executable but make it a relocatable object. */
12025 /* Copy architecture of output file to import library file. */
12033 /* Get symbol table size. */
12038 /* Read in the symbol table. */
12047 /* Allow the BFD backend to copy any private header data it
12048 understands from the output BFD to the import library BFD. */
12052 /* Filter symbols to appear in the import library. */
12055 symcount);
12056 else
12059 {
12062 implib_bfd);
12064 }
12067 /* Make symbols absolute. */
12074 {
12083 }
12087 /* Allow the BFD backend to copy any private data it understands
12088 from the output BFD to the import library BFD. This is done last
12089 to permit the routine to look at the filtered symbol table. */
12098 free_sym_buf:
12101 }
12103 static void
12105 {
12121 {
12125 }
12126 }
12128 /* Do the final step of an ELF link. */
12130 bfd_boolean
12132 {
12133 bfd_boolean dynamic;
12134 bfd_boolean emit_relocs;
12140 bfd_size_type max_contents_size;
12141 bfd_size_type max_external_reloc_size;
12142 bfd_size_type max_internal_reloc_count;
12143 bfd_size_type max_sym_count;
12144 bfd_size_type max_sym_shndx_count;
12145 Elf_Internal_Sym elfsym;
12151 bfd_boolean merged;
12154 bfd_size_type amt;
12159 bfd_boolean sections_removed;
12160 bfd_boolean ret;
12182 {
12185 }
12186 else
12187 {
12189 /* Note that dynsym_sec can be NULL (on VMS). */
12191 /* Note that it is OK if symver_sec is NULL. */
12192 }
12196 local_hash_newfunc,
12200 /* The object attributes have been merged. Remove the input
12201 sections from the link, and set the contents of the output
12202 section. */
12206 {
12211 {
12213 {
12219 /* Hack: reset the SEC_HAS_CONTENTS flag so that
12220 elf_link_input_bfd ignores this section. */
12222 }
12226 /* Skip this section later on. */
12230 else
12232 }
12234 {
12235 /* Remove empty group section from linker output. */
12237 }
12239 {
12244 }
12245 }
12249 /* Count up the number of relocations we will output for each output
12250 section, so that we know the sizes of the reloc sections. We
12251 also figure out some maximum sizes. */
12259 {
12264 {
12273 {
12278 /* Mark all sections which are to be included in the
12279 link. This will normally be every section. We need
12280 to do this so that we can identify any sections which
12281 the linker has decided to not include. */
12294 {
12297 /* We are interested in just local symbols, not all
12298 symbols. */
12302 else
12314 /* Some backends use reloc_count in relocation sections
12315 to count particular types of relocs. Of course,
12316 reloc sections themselves can't have relocations. */
12317 ;
12319 {
12322 {
12326 }
12327 }
12334 {
12346 }
12347 }
12348 }
12357 {
12359 {
12362 }
12364 {
12367 }
12368 }
12369 else
12370 {
12373 else
12375 }
12376 }
12380 else
12381 {
12382 /* Explicitly clear the SEC_RELOC flag. The linker tends to
12383 set it (this is probably a bug) and if it is set
12384 assign_section_numbers will create a reloc section. */
12386 }
12388 /* If the SEC_ALLOC flag is not set, force the section VMA to
12389 zero. This is done in elf_fake_sections as well, but forcing
12390 the VMA to 0 here will ensure that relocs against these
12391 sections are handled correctly. */
12395 }
12400 /* Figure out the file positions for everything but the symbol table
12401 and the relocs. We set symcount to force assign_section_numbers
12402 to create a symbol table. */
12408 /* Set sizes, and assign file positions for reloc sections. */
12410 {
12413 {
12421 }
12423 /* _bfd_elf_compute_section_file_positions makes temporary use
12424 of target_index. Reset it. */
12427 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
12428 to count upwards while actually outputting the relocations. */
12434 {
12435 /* Cache the section contents so that they can be compressed
12436 later. Use bfd_malloc since it will be freed by
12437 bfd_compress_section_contents. */
12441 contents
12446 }
12447 }
12449 /* We have now assigned file positions for all the sections except .symtab,
12450 .strtab, and non-loaded reloc and compressed debugging sections. We start
12451 the .symtab section at the current file position, and write directly to it.
12452 We build the .strtab section in memory. */
12455 /* sh_name is set in prep_headers. */
12457 /* sh_flags, sh_addr and sh_size all start off zero. */
12459 /* sh_link is set in assign_section_numbers. */
12460 /* sh_info is set below. */
12461 /* sh_offset is set just below. */
12471 /* The real buffer will be allocated in elf_link_swap_symbols_out. */
12472 flinfo.symshndxbuf
12477 {
12478 bfd_boolean name_local_sections;
12485 /* Note that at this point elf_next_file_pos (abfd) is
12486 incorrect. We do not yet know the size of the .symtab section.
12487 We correct next_file_pos below, after we do know the size. */
12489 /* Start writing out the symbol table. The first symbol is always a
12490 dummy symbol. */
12501 /* Output a symbol for each section. We output these even if we are
12502 discarding local symbols, since they are used for relocs. These
12503 symbols usually have no names. We store the index of each one in
12504 the index field of the section, so that we can find it again when
12505 outputting relocs. */
12507 name_local_sections
12518 {
12521 {
12531 }
12532 }
12533 }
12535 /* On some targets like Irix 5 the symbol split between local and global
12536 ones recorded in the sh_info field needs to be done between section
12537 and all other symbols. */
12542 /* Allocate some memory to hold information read in from the input
12543 files. */
12545 {
12549 }
12552 {
12556 }
12559 {
12564 }
12567 {
12587 }
12590 {
12595 }
12598 {
12605 {
12611 {
12616 }
12618 }
12620 /* Only align end of TLS section if static TLS doesn't have special
12621 alignment requirements. */
12625 }
12627 /* Reorder SHF_LINK_ORDER sections. */
12629 {
12632 }
12637 /* Since ELF permits relocations to be against local symbols, we
12638 must have the local symbols available when we do the relocations.
12639 Since we would rather only read the local symbols once, and we
12640 would rather not keep them in memory, we handle all the
12641 relocations for a single input file at the same time.
12643 Unfortunately, there is no way to know the total number of local
12644 symbols until we have seen all of them, and the local symbol
12645 indices precede the global symbol indices. This means that when
12646 we are generating relocatable output, and we see a reloc against
12647 a global symbol, we can not know the symbol index until we have
12648 finished examining all the local symbols to see which ones we are
12649 going to output. To deal with this, we keep the relocations in
12650 memory, and don't output them until the end of the link. This is
12651 an unfortunate waste of memory, but I don't see a good way around
12652 it. Fortunately, it only happens when performing a relocatable
12653 link, which is not the common case. FIXME: If keep_memory is set
12654 we could write the relocs out and then read them again; I don't
12655 know how bad the memory loss will be. */
12660 {
12662 {
12667 {
12669 {
12673 }
12674 }
12677 {
12680 }
12681 else
12682 {
12684 {
12690 {
12694 {
12699 }
12702 {
12707 }
12710 _bfd_error_handler
12711 /* xgettext:c-format */
12714 }
12717 }
12718 }
12719 }
12720 }
12722 /* Free symbol buffer if needed. */
12724 {
12727 {
12730 }
12731 }
12735 /* Output any global symbols that got converted to local in a
12736 version script or due to symbol visibility. We do this in a
12737 separate step since ELF requires all local symbols to appear
12738 prior to any global symbols. FIXME: We should only do this if
12739 some global symbols were, in fact, converted to become local.
12740 FIXME: Will this work correctly with the Irix 5 linker? */
12747 {
12750 }
12752 /* If backend needs to output some local symbols not present in the hash
12753 table, do it now. */
12756 {
12764 {
12767 }
12768 }
12770 /* That wrote out all the local symbols. Finish up the symbol table
12771 with the global symbols. Even if we want to strip everything we
12772 can, we still need to deal with those global symbols that got
12773 converted to local in a version script. */
12775 /* The sh_info field records the index of the first non local symbol. */
12782 {
12783 Elf_Internal_Sym sym;
12789 /* Write out the section symbols for the output sections. */
12792 {
12802 {
12814 {
12817 }
12821 /* Inform the linker of the addition of this symbol. */
12827 }
12828 }
12830 /* Write out the local dynsyms. */
12832 {
12835 {
12839 /* Copy the internal symbol and turn off visibility.
12840 Note that we saved a word of storage and overwrote
12841 the original st_name with the dynstr_index. */
12851 {
12855 {
12858 }
12862 }
12864 /* Inform the linker of the addition of this symbol. */
12871 }
12872 }
12873 }
12875 /* We get the global symbols from the hash table. */
12881 {
12884 }
12886 /* If backend needs to output some symbols not present in the hash
12887 table, do it now. */
12890 {
12898 {
12901 }
12902 }
12904 /* Finalize the .strtab section. */
12907 /* Swap out the .strtab section. */
12909 {
12912 }
12914 /* Now we know the size of the symtab section. */
12916 {
12917 /* Finish up and write out the symbol string table (.strtab)
12918 section. */
12923 {
12927 {
12939 {
12942 }
12943 }
12944 }
12947 /* sh_name was set in prep_headers. */
12955 /* sh_offset is set just below. */
12964 {
12967 }
12968 }
12971 {
12976 }
12978 /* Adjust the relocs to have the correct symbol indices. */
12980 {
12982 bfd_boolean sort;
12990 {
12993 }
12996 {
12999 }
13001 /* Set the reloc_count field to 0 to prevent write_relocs from
13002 trying to swap the relocs out itself. */
13004 }
13009 /* If we are linking against a dynamic object, or generating a
13010 shared library, finish up the dynamic linking information. */
13012 {
13015 /* Fix up .dynamic entries. */
13022 {
13023 Elf_Internal_Dyn dyn;
13026 bfd_size_type sh_size;
13027 bfd_vma sh_addr;
13032 {
13037 {
13039 {
13043 }
13047 }
13055 get_sym:
13056 {
13063 {
13069 else
13070 {
13071 /* The symbol is imported from another shared
13072 library and does not apply to this one. */
13074 }
13076 }
13077 }
13088 get_out_size:
13091 {
13092 _bfd_error_handler
13095 }
13097 _bfd_error_handler
13110 get_out_vma:
13134 get_vma:
13136 do_vma:
13138 {
13139 _bfd_error_handler
13142 }
13144 {
13145 _bfd_error_handler
13149 }
13159 else
13164 {
13170 {
13175 }
13176 }
13179 {
13182 /* Don't count procedure linkage table relocs in the
13183 overall reloc count. */
13186 /* If the size is zero, make the address zero too.
13187 This is to avoid a glibc bug. If the backend
13188 emits DT_RELA/DT_RELASZ even when DT_RELASZ is
13189 zero, then we'll put DT_RELA at the end of
13190 DT_JMPREL. glibc will interpret the end of
13191 DT_RELA matching the end of DT_JMPREL as the
13192 case where DT_RELA includes DT_JMPREL, and for
13193 LD_BIND_NOW will decide that processing DT_RELA
13194 will process the PLT relocs too. Net result:
13195 No PLT relocs applied. */
13198 /* If .rela.plt is the first .rela section, exclude
13199 it from DT_RELA. */
13203 }
13207 else
13210 }
13212 }
13213 }
13215 /* If we have created any dynamic sections, then output them. */
13217 {
13221 /* Check for DT_TEXTREL (late, in case the backend removes it). */
13224 {
13230 {
13231 Elf_Internal_Dyn dyn;
13236 {
13243 else
13247 }
13248 }
13249 }
13252 {
13258 {
13259 /* At this point, we are only interested in sections
13260 created by _bfd_elf_link_create_dynamic_sections. */
13262 }
13268 {
13274 }
13275 else
13276 {
13277 /* The contents of the .dynstr section are actually in a
13278 stringtab. */
13279 file_ptr off;
13285 }
13286 }
13287 }
13290 {
13297 }
13299 /* If we have optimized stabs strings, output them. */
13301 {
13304 }
13315 {
13318 {
13319 /* Bail out and fail. */
13322 }
13326 }
13328 return_local_hash_table:
13333 error_return:
13337 }
13338 \f
13339 /* Initialize COOKIE for input bfd ABFD. */
13341 static bfd_boolean
13344 {
13355 {
13358 }
13359 else
13360 {
13363 }
13367 else
13372 {
13377 {
13380 }
13383 }
13385 }
13387 /* Free the memory allocated by init_reloc_cookie, if appropriate. */
13389 static void
13391 {
13397 }
13399 /* Initialize the relocation information in COOKIE for input section SEC
13400 of input bfd ABFD. */
13402 static bfd_boolean
13406 {
13408 {
13411 }
13412 else
13413 {
13420 }
13423 }
13425 /* Free the memory allocated by init_reloc_cookie_rels,
13426 if appropriate. */
13428 static void
13431 {
13434 }
13436 /* Initialize the whole of COOKIE for input section SEC. */
13438 static bfd_boolean
13442 {
13449 error2:
13451 error1:
13453 }
13455 /* Free the memory allocated by init_reloc_cookie_for_section,
13456 if appropriate. */
13458 static void
13461 {
13464 }
13465 \f
13466 /* Garbage collect unused sections. */
13468 /* Default gc_mark_hook. */
13470 asection *
13476 {
13478 {
13480 {
13490 }
13491 }
13492 else
13496 }
13498 /* Return the debug definition section. */
13506 {
13508 {
13509 /* Return the global debug definition section. */
13514 }
13515 else
13516 {
13517 /* Return the local debug definition section. */
13522 }
13525 }
13527 /* COOKIE->rel describes a relocation against section SEC, which is
13528 a section we've decided to keep. Return the section that contains
13529 the relocation symbol, or NULL if no section contains it. */
13531 asection *
13533 elf_gc_mark_hook_fn gc_mark_hook,
13536 {
13546 {
13549 {
13553 }
13558 /* Keep all aliases of the symbol too. If an object symbol
13559 needs to be copied into .dynbss then all of its aliases
13560 should be present as dynamic symbols, not just the one used
13561 on the copy relocation. */
13564 {
13567 }
13570 {
13571 /* To work around a glibc bug, mark XXX input sections
13572 when there is a reference to __start_XXX or __stop_XXX
13573 symbols. */
13575 {
13579 }
13580 }
13583 }
13587 }
13589 /* COOKIE->rel describes a relocation against section SEC, which is
13590 a section we've decided to keep. Mark the section that contains
13591 the relocation symbol. */
13593 bfd_boolean
13596 elf_gc_mark_hook_fn gc_mark_hook,
13598 {
13604 {
13606 {
13612 }
13616 }
13618 }
13620 /* The mark phase of garbage collection. For a given section, mark
13621 it and any sections in this section's group, and all the sections
13622 which define symbols to which it refers. */
13624 bfd_boolean
13627 elf_gc_mark_hook_fn gc_mark_hook)
13628 {
13629 bfd_boolean ret;
13634 /* Mark all the sections in the group. */
13640 /* Look through the section relocs. */
13646 {
13651 else
13652 {
13655 {
13658 }
13660 }
13661 }
13664 {
13669 else
13670 {
13675 }
13676 }
13684 }
13686 /* Scan and mark sections in a special or debug section group. */
13688 static void
13690 {
13691 /* Point to first section of section group. */
13693 /* Used to iterate the section group. */
13699 /* First scan to see if group contains any section other than debug
13700 and special section. */
13702 do
13703 {
13711 }
13714 /* If this is a pure debug section group or pure special section group,
13715 keep all sections in this group. */
13717 {
13718 do
13719 {
13722 }
13724 }
13725 }
13727 /* Keep debug and special sections. */
13729 bfd_boolean
13731 elf_gc_mark_hook_fn mark_hook)
13732 {
13736 {
13738 bfd_boolean some_kept;
13739 bfd_boolean debug_frag_seen;
13740 bfd_boolean has_kept_debug_info;
13748 /* Ensure all linker created sections are kept,
13749 see if any other section is already marked,
13750 and note if we have any fragmented debug sections. */
13753 {
13760 else
13761 {
13762 /* Since all sections, except for backend specific ones,
13763 have been garbage collected, call mark_hook on this
13764 section if any of its linked-to sections is marked. */
13769 {
13773 }
13774 }
13784 "need linked-to section "
13787 }
13789 /* If no non-note alloc section in this file will be kept, then
13790 we can toss out the debug and special sections. */
13794 /* Keep debug and special sections like .comment when they are
13795 not part of a group. Also keep section groups that contain
13796 just debug sections or special sections. NB: Sections with
13797 linked-to section has been handled above. */
13799 {
13809 }
13811 /* Look for CODE sections which are going to be discarded,
13812 and find and discard any fragmented debug sections which
13813 are associated with that code section. */
13818 {
13824 /* Association is determined by the name of the debug
13825 section containing the name of the code section as
13826 a suffix. For example .debug_line.text.foo is a
13827 debug section associated with .text.foo. */
13829 {
13842 }
13843 }
13845 /* Mark debug sections referenced by kept debug sections. */
13851 elf_gc_mark_debug_section))
13853 }
13855 }
13857 static bfd_boolean
13859 {
13864 {
13876 {
13877 /* When any section in a section group is kept, we keep all
13878 sections in the section group. If the first member of
13879 the section group is excluded, we will also exclude the
13880 group section. */
13882 {
13885 }
13890 /* Skip sweeping sections already excluded. */
13894 /* Since this is early in the link process, it is simple
13895 to remove a section from the output. */
13899 /* xgettext:c-format */
13902 }
13903 }
13906 }
13908 /* Propagate collected vtable information. This is called through
13909 elf_link_hash_traverse. */
13911 static bfd_boolean
13913 {
13914 /* Those that are not vtables. */
13920 /* Those vtables that do not have parents, we cannot merge. */
13924 /* If we've already been done, exit. */
13928 /* Make sure the parent's table is up to date. */
13932 {
13933 /* None of this table's entries were referenced. Re-use the
13934 parent's table. */
13937 }
13938 else
13939 {
13943 /* Or the parent's entries into ours. */
13948 {
13956 {
13959 pu++;
13960 cu++;
13961 }
13962 }
13963 }
13966 }
13968 static bfd_boolean
13970 {
13977 /* Take care of both those symbols that do not describe vtables as
13978 well as those that are not loaded. */
14001 {
14002 /* If the entry is in use, do nothing. */
14005 {
14009 }
14010 /* Otherwise, kill it. */
14012 }
14015 }
14017 /* Mark sections containing dynamically referenced symbols. When
14018 building shared libraries, we must assume that any visible symbol is
14019 referenced. */
14021 bfd_boolean
14023 {
14045 }
14047 /* Keep all sections containing symbols undefined on the command-line,
14048 and the section containing the entry symbol. */
14050 void
14052 {
14056 {
14067 }
14068 }
14070 bfd_boolean
14073 {
14077 {
14091 {
14094 {
14097 }
14098 }
14099 }
14101 }
14103 /* Do mark and sweep of unused sections. */
14105 bfd_boolean
14107 {
14110 elf_gc_mark_hook_fn gc_mark_hook;
14116 {
14119 }
14124 /* Try to parse each bfd's .eh_frame section. Point elf_eh_frame_section
14125 at the .eh_frame section if we can mark the FDEs individually. */
14129 {
14138 {
14145 }
14146 }
14148 /* Apply transitive closure to the vtable entry usage info. */
14153 /* Kill the vtable relocations that were not used. */
14158 /* Mark dynamically referenced symbols. */
14162 /* Grovel through relocs to find out who stays ... */
14165 {
14177 /* Start at sections marked with SEC_KEEP (ref _bfd_elf_gc_keep).
14178 Also treat note sections as a root, if the section is not part
14179 of a group. We must keep all PREINIT_ARRAY, INIT_ARRAY as
14180 well as FINI_ARRAY sections for ld -r. */
14197 {
14200 }
14201 }
14203 /* Allow the backend to mark additional target specific sections. */
14206 /* ... and mark SEC_EXCLUDE for those that go. */
14208 }
14209 \f
14210 /* Called from check_relocs to record the existence of a VTINHERIT reloc. */
14212 bfd_boolean
14216 bfd_vma offset)
14217 {
14223 /* The sh_info field of the symtab header tells us where the
14224 external symbols start. We don't care about the local symbols at
14225 this point. */
14233 /* Hunt down the child symbol, which is in this section at the same
14234 offset as the relocation. */
14236 {
14243 }
14245 /* xgettext:c-format */
14251 win:
14253 {
14258 }
14260 {
14261 /* This *should* only be the absolute section. It could potentially
14262 be that someone has defined a non-global vtable though, which
14263 would be bad. It isn't worth paging in the local symbols to be
14264 sure though; that case should simply be handled by the assembler. */
14267 }
14268 else
14272 }
14274 /* Called from check_relocs to record the existence of a VTENTRY reloc. */
14276 bfd_boolean
14279 bfd_vma addend)
14280 {
14285 {
14286 /* xgettext:c-format */
14291 }
14294 {
14299 }
14302 {
14306 /* While the symbol is undefined, we have to be prepared to handle
14307 a zero size. */
14311 else
14312 {
14315 {
14316 /* Oops! We've got a reference past the defined end of
14317 the table. This is probably a bug -- shall we warn? */
14319 }
14320 }
14323 /* Allocate one extra entry for use as a "done" flag for the
14324 consolidation pass. */
14328 {
14332 {
14338 }
14339 }
14340 else
14346 /* And arrange for that done flag to be at index -1. */
14349 }
14354 }
14356 /* Map an ELF section header flag to its corresponding string. */
14358 {
14360 flagword flag_value;
14364 {
14377 };
14379 /* Returns TRUE if the section is to be included, otherwise FALSE. */
14380 bfd_boolean
14384 {
14388 {
14396 {
14402 {
14406 {
14413 }
14414 }
14416 {
14418 {
14425 }
14426 }
14428 {
14432 }
14433 }
14437 }
14446 }
14449 bfd_vma gotoff;
14451 };
14453 /* We need a special top-level link routine to convert got reference counts
14454 to real got offsets. */
14456 static bfd_boolean
14458 {
14464 {
14467 }
14468 else
14472 }
14474 /* And an accompanying bit to work out final got entry offsets once
14475 we're done. Should be called from final_link. */
14477 bfd_boolean
14480 {
14483 bfd_vma gotoff;
14491 /* The GOT offset is relative to the .got section, but the GOT header is
14492 put into the .got.plt section, if the backend uses it. */
14495 else
14498 /* Do the local .got entries first. */
14500 {
14515 else
14519 {
14521 {
14524 }
14525 else
14527 }
14528 }
14530 /* Then the global .got entries. .plt refcounts are handled by
14531 adjust_dynamic_symbol */
14535 elf_gc_allocate_got_offsets,
14538 }
14540 /* Many folk need no more in the way of final link than this, once
14541 got entry reference counting is enabled. */
14543 bfd_boolean
14545 {
14549 /* Invoke the regular ELF backend linker to do all the work. */
14551 }
14553 bfd_boolean
14555 {
14562 {
14577 {
14592 }
14593 else
14594 {
14595 /* It's not a relocation against a global symbol,
14596 but it could be a relocation against a local
14597 symbol for a discarded section. */
14601 /* Need to: get the symbol; get the section. */
14608 }
14610 }
14612 }
14614 /* Discard unneeded references to discarded sections.
14615 Returns -1 on error, 1 if any section's size was changed, 0 if
14616 nothing changed. This function assumes that the relocations are in
14617 sorted order, which is true for all known assemblers. */
14619 int
14621 {
14633 {
14637 {
14652 bfd_elf_reloc_symbol_deleted_p,
14657 }
14658 }
14664 {
14670 {
14683 bfd_elf_reloc_symbol_deleted_p,
14685 {
14689 }
14692 }
14696 /* Skip over zero terminator, and prevent empty sections from
14697 adding alignment padding at the end. */
14703 /* The last non-empty eh_frame section doesn't need padding. */
14706 /* Any prior sections must pad the last FDE out to the output
14707 section alignment. Otherwise we might have zero padding
14708 between sections, which would be seen as a terminator. */
14711 /* All but the last zero terminator should have been removed. */
14713 else
14714 {
14715 bfd_size_type size
14718 {
14722 }
14723 }
14727 }
14730 {
14743 {
14751 }
14752 }
14763 }
14765 bfd_boolean
14769 {
14770 flagword flags;
14780 /* Return if it isn't a linkonce section. A comdat group section
14781 also has SEC_LINK_ONCE set. */
14785 /* Don't put group member sections on our list of already linked
14786 sections. They are handled as a group via their group section. */
14790 /* For a SHT_GROUP section, use the group signature as the key. */
14796 else
14797 {
14798 /* Otherwise we should have a .gnu.linkonce.<type>.<key> section. */
14801 key++;
14802 else
14803 /* Must be a user linkonce section that doesn't follow gcc's
14804 naming convention. In this case we won't be matching
14805 single member groups. */
14807 }
14812 {
14813 /* We may have 2 different types of sections on the list: group
14814 sections with a signature of <key> (<key> is some string),
14815 and linkonce sections named .gnu.linkonce.<type>.<key>.
14816 Match like sections. LTO plugin sections are an exception.
14817 They are always named .gnu.linkonce.t.<key> and match either
14818 type of section. */
14824 {
14825 /* The section has already been linked. See if we should
14826 issue a warning. */
14831 {
14836 {
14838 /* Record which group discards it. */
14841 /* These lists are circular. */
14844 }
14845 }
14848 }
14849 }
14851 /* A single member comdat group section may be discarded by a
14852 linkonce section and vice versa. */
14854 {
14858 /* Check this single member group against linkonce sections. */
14862 {
14867 }
14868 }
14869 else
14870 /* Check this linkonce section against single member groups. */
14873 {
14879 {
14883 }
14884 }
14886 /* Do not complain on unresolved relocations in `.gnu.linkonce.r.F'
14887 referencing its discarded `.gnu.linkonce.t.F' counterpart - g++-3.4
14888 specific as g++-4.x is using COMDAT groups (without the `.gnu.linkonce'
14889 prefix) instead. `.gnu.linkonce.r.*' were the `.rodata' part of its
14890 matching `.gnu.linkonce.t.*'. If `.gnu.linkonce.r.F' is not discarded
14891 but its `.gnu.linkonce.t.F' is discarded means we chose one-only
14892 `.gnu.linkonce.t.F' section from a different bfd not requiring any
14893 `.gnu.linkonce.r.F'. Thus `.gnu.linkonce.r.F' should be discarded.
14894 The reverse order cannot happen as there is never a bfd with only the
14895 `.gnu.linkonce.r.F' section. The order of sections in a bfd does not
14896 matter as here were are looking only for cross-bfd sections. */
14902 {
14906 }
14908 /* This is the first section with this name. Record it. */
14912 }
14914 bfd_boolean
14916 {
14918 }
14920 unsigned int
14922 {
14924 }
14926 asection *
14928 {
14930 }
14932 bfd_vma
14938 {
14941 }
14943 /* Routines to support the creation of dynamic relocs. */
14945 /* Returns the name of the dynamic reloc section associated with SEC. */
14950 bfd_boolean is_rela)
14951 {
14963 }
14965 /* Returns the dynamic reloc section associated with SEC.
14966 If necessary compute the name of the dynamic reloc section based
14967 on SEC's name (looked up in ABFD's string table) and the setting
14968 of IS_RELA. */
14970 asection *
14973 bfd_boolean is_rela)
14974 {
14978 {
14982 {
14987 }
14988 }
14991 }
14993 /* Returns the dynamic reloc section associated with SEC. If the
14994 section does not exist it is created and attached to the DYNOBJ
14995 bfd and stored in the SRELOC field of SEC's elf_section_data
14996 structure.
14998 ALIGNMENT is the alignment for the newly created section and
14999 IS_RELA defines whether the name should be .rela.<SEC's name>
15000 or .rel.<SEC's name>. The section name is looked up in the
15001 string table associated with ABFD. */
15003 asection *
15008 bfd_boolean is_rela)
15009 {
15013 {
15022 {
15030 {
15031 /* _bfd_elf_get_sec_type_attr chooses a section type by
15032 name. Override as it may be wrong, eg. for a user
15033 section named "auto" we'll get ".relauto" which is
15034 seen to be a .rela section. */
15038 }
15039 }
15042 }
15045 }
15047 /* Copy the ELF symbol type and other attributes for a linker script
15048 assignment from HSRC to HDEST. Generally this should be treated as
15049 if we found a strong non-dynamic definition for HDEST (except that
15050 ld ignores multiple definition errors). */
15051 void
15055 {
15058 Elf_Internal_Sym isym;
15065 }
15067 /* Append a RELA relocation REL to section S in BFD. */
15069 void
15071 {
15076 }
15078 /* Append a REL relocation REL to section S in BFD. */
15080 void
15082 {
15087 }
15089 /* Define __start, __stop, .startof. or .sizeof. symbol. */
15094 {
15099 /* NB: Common symbols will be turned into definition later. */
15106 {
15117 {
15118 /* .startof. and .sizeof. symbols are local. */
15122 }
15123 else
15124 {
15130 }
15132 }
15134 }
15136 /* Find dynamic relocs for H that apply to read-only sections. */
15138 asection *
15140 {
15144 {
15149 }
15151 }
15153 /* Set DF_TEXTREL if we find any dynamic relocs that apply to
15154 read-only sections. */
15156 bfd_boolean
15158 {
15166 {
15170 /* xgettext:c-format */
15176 /* xgettext:c-format */
15181 /* Not an error, just cut short the traversal. */
15183 }
15185 }
15187 /* Add dynamic tags. */
15189 bfd_boolean
15191 bfd_boolean need_dynamic_reloc)
15192 {
15196 {
15197 /* Add some entries to the .dynamic section. We fill in the
15198 values later, in finish_dynamic_sections, but we must add
15199 the entries now so that we get the correct size for the
15200 .dynamic section. The DT_DEBUG entry is filled in by the
15201 dynamic linker and used by the debugger. */
15202 #define add_dynamic_entry(TAG, VAL) \
15203 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
15209 {
15212 }
15215 {
15216 /* DT_PLTGOT is used by prelink even if there is no PLT
15217 relocation. */
15220 }
15223 {
15230 }
15238 {
15240 {
15246 }
15247 else
15248 {
15254 }
15256 /* If any dynamic relocs apply to a read-only section,
15257 then we need a DT_TEXTREL entry. */
15260 info);
15263 {
15272 }
15273 }
15274 }
15275 #undef add_dynamic_entry
15278 }