* object.cc (Sized_relobj::do_layout): Defer layout for reloc sections.
[external/binutils.git] / gold / target-reloc.h
1 // target-reloc.h -- target specific relocation support  -*- C++ -*-
2
3 // Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
5
6 // This file is part of gold.
7
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
12
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 // GNU General Public License for more details.
17
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
22
23 #ifndef GOLD_TARGET_RELOC_H
24 #define GOLD_TARGET_RELOC_H
25
26 #include "elfcpp.h"
27 #include "symtab.h"
28 #include "object.h"
29 #include "reloc.h"
30 #include "reloc-types.h"
31
32 namespace gold
33 {
34
35 // This function implements the generic part of reloc scanning.  The
36 // template parameter Scan must be a class type which provides two
37 // functions: local() and global().  Those functions implement the
38 // machine specific part of scanning.  We do it this way to
39 // avoidmaking a function call for each relocation, and to avoid
40 // repeating the generic code for each target.
41
42 template<int size, bool big_endian, typename Target_type, int sh_type,
43          typename Scan>
44 inline void
45 scan_relocs(
46     Symbol_table* symtab,
47     Layout* layout,
48     Target_type* target,
49     Sized_relobj<size, big_endian>* object,
50     unsigned int data_shndx,
51     const unsigned char* prelocs,
52     size_t reloc_count,
53     Output_section* output_section,
54     bool needs_special_offset_handling,
55     size_t local_count,
56     const unsigned char* plocal_syms)
57 {
58   typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
59   const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
60   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
61   Scan scan;
62
63   for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
64     {
65       Reltype reloc(prelocs);
66
67       if (needs_special_offset_handling
68           && !output_section->is_input_address_mapped(object, data_shndx,
69                                                       reloc.get_r_offset()))
70         continue;
71
72       typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
73       unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
74       unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
75
76       if (r_sym < local_count)
77         {
78           gold_assert(plocal_syms != NULL);
79           typename elfcpp::Sym<size, big_endian> lsym(plocal_syms
80                                                       + r_sym * sym_size);
81           unsigned int shndx = lsym.get_st_shndx();
82           bool is_ordinary;
83           shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
84           if (is_ordinary
85               && shndx != elfcpp::SHN_UNDEF
86               && !object->is_section_included(shndx)
87               && !symtab->is_section_folded(object, shndx))
88             {
89               // RELOC is a relocation against a local symbol in a
90               // section we are discarding.  We can ignore this
91               // relocation.  It will eventually become a reloc
92               // against the value zero.
93               //
94               // FIXME: We should issue a warning if this is an
95               // allocated section; is this the best place to do it?
96               // 
97               // FIXME: The old GNU linker would in some cases look
98               // for the linkonce section which caused this section to
99               // be discarded, and, if the other section was the same
100               // size, change the reloc to refer to the other section.
101               // That seems risky and weird to me, and I don't know of
102               // any case where it is actually required.
103
104               continue;
105             }
106           scan.local(symtab, layout, target, object, data_shndx,
107                      output_section, reloc, r_type, lsym);
108         }
109       else
110         {
111           Symbol* gsym = object->global_symbol(r_sym);
112           gold_assert(gsym != NULL);
113           if (gsym->is_forwarder())
114             gsym = symtab->resolve_forwards(gsym);
115
116           scan.global(symtab, layout, target, object, data_shndx,
117                       output_section, reloc, r_type, gsym);
118         }
119     }
120 }
121
122 // Behavior for relocations to discarded comdat sections.
123
124 enum Comdat_behavior
125 {
126   CB_UNDETERMINED,   // Not yet determined -- need to look at section name.
127   CB_PRETEND,        // Attempt to map to the corresponding kept section.
128   CB_IGNORE,         // Ignore the relocation.
129   CB_WARNING         // Print a warning.
130 };
131
132 // Decide what the linker should do for relocations that refer to discarded
133 // comdat sections.  This decision is based on the name of the section being
134 // relocated.
135
136 inline Comdat_behavior
137 get_comdat_behavior(const char* name)
138 {
139   if (Layout::is_debug_info_section(name))
140     return CB_PRETEND;
141   if (strcmp(name, ".eh_frame") == 0
142       || strcmp(name, ".gcc_except_table") == 0)
143     return CB_IGNORE;
144   return CB_WARNING;
145 }
146
147 // Give an error for a symbol with non-default visibility which is not
148 // defined locally.
149
150 inline void
151 visibility_error(const Symbol* sym)
152 {
153   const char* v;
154   switch (sym->visibility())
155     {
156     case elfcpp::STV_INTERNAL:
157       v = _("internal");
158       break;
159     case elfcpp::STV_HIDDEN:
160       v = _("hidden");
161       break;
162     case elfcpp::STV_PROTECTED:
163       v = _("protected");
164       break;
165     default:
166       gold_unreachable();
167     }
168   gold_error(_("%s symbol '%s' is not defined locally"),
169              v, sym->name());
170 }
171
172 // This function implements the generic part of relocation processing.
173 // The template parameter Relocate must be a class type which provides
174 // a single function, relocate(), which implements the machine
175 // specific part of a relocation.
176
177 // SIZE is the ELF size: 32 or 64.  BIG_ENDIAN is the endianness of
178 // the data.  SH_TYPE is the section type: SHT_REL or SHT_RELA.
179 // RELOCATE implements operator() to do a relocation.
180
181 // PRELOCS points to the relocation data.  RELOC_COUNT is the number
182 // of relocs.  OUTPUT_SECTION is the output section.
183 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
184 // mapped to output offsets.
185
186 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
187 // VIEW_SIZE is the size.  These refer to the input section, unless
188 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
189 // the output section.
190
191 // RELOC_SYMBOL_CHANGES is used for -fsplit-stack support.  If it is
192 // not NULL, it is a vector indexed by relocation index.  If that
193 // entry is not NULL, it points to a global symbol which used as the
194 // symbol for the relocation, ignoring the symbol index in the
195 // relocation.
196
197 template<int size, bool big_endian, typename Target_type, int sh_type,
198          typename Relocate>
199 inline void
200 relocate_section(
201     const Relocate_info<size, big_endian>* relinfo,
202     Target_type* target,
203     const unsigned char* prelocs,
204     size_t reloc_count,
205     Output_section* output_section,
206     bool needs_special_offset_handling,
207     unsigned char* view,
208     typename elfcpp::Elf_types<size>::Elf_Addr view_address,
209     section_size_type view_size,
210     const Reloc_symbol_changes* reloc_symbol_changes)
211 {
212   typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
213   const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
214   Relocate relocate;
215
216   Sized_relobj<size, big_endian>* object = relinfo->object;
217   unsigned int local_count = object->local_symbol_count();
218
219   Comdat_behavior comdat_behavior = CB_UNDETERMINED;
220
221   for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
222     {
223       Reltype reloc(prelocs);
224
225       section_offset_type offset =
226         convert_to_section_size_type(reloc.get_r_offset());
227
228       if (needs_special_offset_handling)
229         {
230           offset = output_section->output_offset(relinfo->object,
231                                                  relinfo->data_shndx,
232                                                  offset);
233           if (offset == -1)
234             continue;
235         }
236
237       typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
238       unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
239       unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
240
241       const Sized_symbol<size>* sym;
242
243       Symbol_value<size> symval;
244       const Symbol_value<size> *psymval;
245       bool is_defined_in_discarded_section;
246       unsigned int shndx;
247       if (r_sym < local_count
248           && (reloc_symbol_changes == NULL
249               || (*reloc_symbol_changes)[i] == NULL))
250         {
251           sym = NULL;
252           psymval = object->local_symbol(r_sym);
253
254           // If the local symbol belongs to a section we are discarding,
255           // and that section is a debug section, try to find the
256           // corresponding kept section and map this symbol to its
257           // counterpart in the kept section.  The symbol must not 
258           // correspond to a section we are folding.
259           bool is_ordinary;
260           shndx = psymval->input_shndx(&is_ordinary);
261           is_defined_in_discarded_section =
262             (is_ordinary
263              && shndx != elfcpp::SHN_UNDEF
264              && !object->is_section_included(shndx)
265              && !relinfo->symtab->is_section_folded(object, shndx));
266         }
267       else
268         {
269           const Symbol* gsym;
270           if (reloc_symbol_changes != NULL
271               && (*reloc_symbol_changes)[i] != NULL)
272             gsym = (*reloc_symbol_changes)[i];
273           else
274             {
275               gsym = object->global_symbol(r_sym);
276               gold_assert(gsym != NULL);
277               if (gsym->is_forwarder())
278                 gsym = relinfo->symtab->resolve_forwards(gsym);
279             }
280
281           sym = static_cast<const Sized_symbol<size>*>(gsym);
282           if (sym->has_symtab_index() && sym->symtab_index() != -1U)
283             symval.set_output_symtab_index(sym->symtab_index());
284           else
285             symval.set_no_output_symtab_entry();
286           symval.set_output_value(sym->value());
287           psymval = &symval;
288
289           is_defined_in_discarded_section =
290             (gsym->is_defined_in_discarded_section()
291              && gsym->is_undefined());
292           shndx = 0;
293         }
294
295       Symbol_value<size> symval2;
296       if (is_defined_in_discarded_section)
297         {
298           if (comdat_behavior == CB_UNDETERMINED)
299             {
300               std::string name = object->section_name(relinfo->data_shndx);
301               comdat_behavior = get_comdat_behavior(name.c_str());
302             }
303           if (comdat_behavior == CB_PRETEND)
304             {
305               // FIXME: This case does not work for global symbols.
306               // We have no place to store the original section index.
307               // Fortunately this does not matter for comdat sections,
308               // only for sections explicitly discarded by a linker
309               // script.
310               bool found;
311               typename elfcpp::Elf_types<size>::Elf_Addr value =
312                 object->map_to_kept_section(shndx, &found);
313               if (found)
314                 symval2.set_output_value(value + psymval->input_value());
315               else
316                 symval2.set_output_value(0);
317             }
318           else
319             {
320               if (comdat_behavior == CB_WARNING)
321                 gold_warning_at_location(relinfo, i, offset,
322                                          _("relocation refers to discarded "
323                                            "section"));
324               symval2.set_output_value(0);
325             }
326           symval2.set_no_output_symtab_entry();
327           psymval = &symval2;
328         }
329
330       if (!relocate.relocate(relinfo, target, output_section, i, reloc,
331                              r_type, sym, psymval, view + offset,
332                              view_address + offset, view_size))
333         continue;
334
335       if (offset < 0 || static_cast<section_size_type>(offset) >= view_size)
336         {
337           gold_error_at_location(relinfo, i, offset,
338                                  _("reloc has bad offset %zu"),
339                                  static_cast<size_t>(offset));
340           continue;
341         }
342
343       if (sym != NULL
344           && (sym->is_undefined() || sym->is_placeholder())
345           && sym->binding() != elfcpp::STB_WEAK
346           && !is_defined_in_discarded_section
347           && !target->is_defined_by_abi(sym)
348           && (!parameters->options().shared()       // -shared
349               || parameters->options().defs()))     // -z defs
350         gold_undefined_symbol_at_location(sym, relinfo, i, offset);
351       else if (sym != NULL
352                && sym->visibility() != elfcpp::STV_DEFAULT
353                && (sym->is_undefined() || sym->is_from_dynobj()))
354         visibility_error(sym);
355
356       if (sym != NULL && sym->has_warning())
357         relinfo->symtab->issue_warning(sym, relinfo, i, offset);
358     }
359 }
360
361 // This class may be used as a typical class for the
362 // Scan_relocatable_reloc parameter to scan_relocatable_relocs.  The
363 // template parameter Classify_reloc must be a class type which
364 // provides a function get_size_for_reloc which returns the number of
365 // bytes to which a reloc applies.  This class is intended to capture
366 // the most typical target behaviour, while still permitting targets
367 // to define their own independent class for Scan_relocatable_reloc.
368
369 template<int sh_type, typename Classify_reloc>
370 class Default_scan_relocatable_relocs
371 {
372  public:
373   // Return the strategy to use for a local symbol which is not a
374   // section symbol, given the relocation type.
375   inline Relocatable_relocs::Reloc_strategy
376   local_non_section_strategy(unsigned int r_type, Relobj*, unsigned int r_sym)
377   {
378     // We assume that relocation type 0 is NONE.  Targets which are
379     // different must override.
380     if (r_type == 0 && r_sym == 0)
381       return Relocatable_relocs::RELOC_DISCARD;
382     return Relocatable_relocs::RELOC_COPY;
383   }
384
385   // Return the strategy to use for a local symbol which is a section
386   // symbol, given the relocation type.
387   inline Relocatable_relocs::Reloc_strategy
388   local_section_strategy(unsigned int r_type, Relobj* object)
389   {
390     if (sh_type == elfcpp::SHT_RELA)
391       return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA;
392     else
393       {
394         Classify_reloc classify;
395         switch (classify.get_size_for_reloc(r_type, object))
396           {
397           case 0:
398             return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0;
399           case 1:
400             return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1;
401           case 2:
402             return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2;
403           case 4:
404             return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4;
405           case 8:
406             return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8;
407           default:
408             gold_unreachable();
409           }
410       }
411   }
412
413   // Return the strategy to use for a global symbol, given the
414   // relocation type, the object, and the symbol index.
415   inline Relocatable_relocs::Reloc_strategy
416   global_strategy(unsigned int, Relobj*, unsigned int)
417   { return Relocatable_relocs::RELOC_COPY; }
418 };
419
420 // Scan relocs during a relocatable link.  This is a default
421 // definition which should work for most targets.
422 // Scan_relocatable_reloc must name a class type which provides three
423 // functions which return a Relocatable_relocs::Reloc_strategy code:
424 // global_strategy, local_non_section_strategy, and
425 // local_section_strategy.  Most targets should be able to use
426 // Default_scan_relocatable_relocs as this class.
427
428 template<int size, bool big_endian, int sh_type,
429          typename Scan_relocatable_reloc>
430 void
431 scan_relocatable_relocs(
432     Symbol_table*,
433     Layout*,
434     Sized_relobj<size, big_endian>* object,
435     unsigned int data_shndx,
436     const unsigned char* prelocs,
437     size_t reloc_count,
438     Output_section* output_section,
439     bool needs_special_offset_handling,
440     size_t local_symbol_count,
441     const unsigned char* plocal_syms,
442     Relocatable_relocs* rr)
443 {
444   typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
445   const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
446   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
447   Scan_relocatable_reloc scan;
448
449   for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
450     {
451       Reltype reloc(prelocs);
452
453       Relocatable_relocs::Reloc_strategy strategy;
454
455       if (needs_special_offset_handling
456           && !output_section->is_input_address_mapped(object, data_shndx,
457                                                       reloc.get_r_offset()))
458         strategy = Relocatable_relocs::RELOC_DISCARD;
459       else
460         {
461           typename elfcpp::Elf_types<size>::Elf_WXword r_info =
462             reloc.get_r_info();
463           const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
464           const unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
465
466           if (r_sym >= local_symbol_count)
467             strategy = scan.global_strategy(r_type, object, r_sym);
468           else
469             {
470               gold_assert(plocal_syms != NULL);
471               typename elfcpp::Sym<size, big_endian> lsym(plocal_syms
472                                                           + r_sym * sym_size);
473               unsigned int shndx = lsym.get_st_shndx();
474               bool is_ordinary;
475               shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
476               if (is_ordinary
477                   && shndx != elfcpp::SHN_UNDEF
478                   && !object->is_section_included(shndx))
479                 {
480                   // RELOC is a relocation against a local symbol
481                   // defined in a section we are discarding.  Discard
482                   // the reloc.  FIXME: Should we issue a warning?
483                   strategy = Relocatable_relocs::RELOC_DISCARD;
484                 }
485               else if (lsym.get_st_type() != elfcpp::STT_SECTION)
486                 strategy = scan.local_non_section_strategy(r_type, object,
487                                                            r_sym);
488               else
489                 {
490                   strategy = scan.local_section_strategy(r_type, object);
491                   if (strategy != Relocatable_relocs::RELOC_DISCARD)
492                     object->output_section(shndx)->set_needs_symtab_index();
493                 }
494
495               if (strategy == Relocatable_relocs::RELOC_COPY)
496                 object->set_must_have_output_symtab_entry(r_sym);
497             }
498         }
499
500       rr->set_next_reloc_strategy(strategy);
501     }
502 }
503
504 // Relocate relocs during a relocatable link.  This is a default
505 // definition which should work for most targets.
506
507 template<int size, bool big_endian, int sh_type>
508 void
509 relocate_for_relocatable(
510     const Relocate_info<size, big_endian>* relinfo,
511     const unsigned char* prelocs,
512     size_t reloc_count,
513     Output_section* output_section,
514     typename elfcpp::Elf_types<size>::Elf_Addr offset_in_output_section,
515     const Relocatable_relocs* rr,
516     unsigned char* view,
517     typename elfcpp::Elf_types<size>::Elf_Addr view_address,
518     section_size_type view_size,
519     unsigned char* reloc_view,
520     section_size_type reloc_view_size)
521 {
522   typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
523   typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
524   typedef typename Reloc_types<sh_type, size, big_endian>::Reloc_write
525     Reltype_write;
526   const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
527   const Address invalid_address = static_cast<Address>(0) - 1;
528
529   Sized_relobj<size, big_endian>* const object = relinfo->object;
530   const unsigned int local_count = object->local_symbol_count();
531
532   unsigned char* pwrite = reloc_view;
533
534   for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
535     {
536       Relocatable_relocs::Reloc_strategy strategy = rr->strategy(i);
537       if (strategy == Relocatable_relocs::RELOC_DISCARD)
538         continue;
539
540       if (strategy == Relocatable_relocs::RELOC_SPECIAL)
541         {
542           // Target wants to handle this relocation.
543           Sized_target<size, big_endian>* target =
544             parameters->sized_target<size, big_endian>();
545           target->relocate_special_relocatable(relinfo, sh_type, prelocs,
546                                                i, output_section,
547                                                offset_in_output_section,
548                                                view, view_address,
549                                                view_size, pwrite);
550           pwrite += reloc_size;
551           continue;
552         }
553       Reltype reloc(prelocs);
554       Reltype_write reloc_write(pwrite);
555
556       typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
557       const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
558       const unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
559
560       // Get the new symbol index.
561
562       unsigned int new_symndx;
563       if (r_sym < local_count)
564         {
565           switch (strategy)
566             {
567             case Relocatable_relocs::RELOC_COPY:
568               if (r_sym == 0)
569                 new_symndx = 0;
570               else
571                 {
572                   new_symndx = object->symtab_index(r_sym);
573                   gold_assert(new_symndx != -1U);
574                 }
575               break;
576
577             case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA:
578             case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0:
579             case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1:
580             case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2:
581             case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4:
582             case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8:
583               {
584                 // We are adjusting a section symbol.  We need to find
585                 // the symbol table index of the section symbol for
586                 // the output section corresponding to input section
587                 // in which this symbol is defined.
588                 gold_assert(r_sym < local_count);
589                 bool is_ordinary;
590                 unsigned int shndx =
591                   object->local_symbol_input_shndx(r_sym, &is_ordinary);
592                 gold_assert(is_ordinary);
593                 Output_section* os = object->output_section(shndx);
594                 gold_assert(os != NULL);
595                 gold_assert(os->needs_symtab_index());
596                 new_symndx = os->symtab_index();
597               }
598               break;
599
600             default:
601               gold_unreachable();
602             }
603         }
604       else
605         {
606           const Symbol* gsym = object->global_symbol(r_sym);
607           gold_assert(gsym != NULL);
608           if (gsym->is_forwarder())
609             gsym = relinfo->symtab->resolve_forwards(gsym);
610
611           gold_assert(gsym->has_symtab_index());
612           new_symndx = gsym->symtab_index();
613         }
614
615       // Get the new offset--the location in the output section where
616       // this relocation should be applied.
617
618       Address offset = reloc.get_r_offset();
619       Address new_offset;
620       if (offset_in_output_section != invalid_address)
621         new_offset = offset + offset_in_output_section;
622       else
623         {
624           section_offset_type sot_offset =
625               convert_types<section_offset_type, Address>(offset);
626           section_offset_type new_sot_offset =
627               output_section->output_offset(object, relinfo->data_shndx,
628                                             sot_offset);
629           gold_assert(new_sot_offset != -1);
630           new_offset = new_sot_offset;
631         }
632
633       // In an object file, r_offset is an offset within the section.
634       // In an executable or dynamic object, generated by
635       // --emit-relocs, r_offset is an absolute address.
636       if (!parameters->options().relocatable())
637         {
638           new_offset += view_address;
639           if (offset_in_output_section != invalid_address)
640             new_offset -= offset_in_output_section;
641         }
642
643       reloc_write.put_r_offset(new_offset);
644       reloc_write.put_r_info(elfcpp::elf_r_info<size>(new_symndx, r_type));
645
646       // Handle the reloc addend based on the strategy.
647
648       if (strategy == Relocatable_relocs::RELOC_COPY)
649         {
650           if (sh_type == elfcpp::SHT_RELA)
651             Reloc_types<sh_type, size, big_endian>::
652               copy_reloc_addend(&reloc_write,
653                                 &reloc);
654         }
655       else
656         {
657           // The relocation uses a section symbol in the input file.
658           // We are adjusting it to use a section symbol in the output
659           // file.  The input section symbol refers to some address in
660           // the input section.  We need the relocation in the output
661           // file to refer to that same address.  This adjustment to
662           // the addend is the same calculation we use for a simple
663           // absolute relocation for the input section symbol.
664
665           const Symbol_value<size>* psymval = object->local_symbol(r_sym);
666
667           unsigned char* padd = view + offset;
668           switch (strategy)
669             {
670             case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA:
671               {
672                 typename elfcpp::Elf_types<size>::Elf_Swxword addend;
673                 addend = Reloc_types<sh_type, size, big_endian>::
674                            get_reloc_addend(&reloc);
675                 addend = psymval->value(object, addend);
676                 Reloc_types<sh_type, size, big_endian>::
677                   set_reloc_addend(&reloc_write, addend);
678               }
679               break;
680
681             case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0:
682               break;
683
684             case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1:
685               Relocate_functions<size, big_endian>::rel8(padd, object,
686                                                          psymval);
687               break;
688
689             case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2:
690               Relocate_functions<size, big_endian>::rel16(padd, object,
691                                                           psymval);
692               break;
693
694             case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4:
695               Relocate_functions<size, big_endian>::rel32(padd, object,
696                                                           psymval);
697               break;
698
699             case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8:
700               Relocate_functions<size, big_endian>::rel64(padd, object,
701                                                           psymval);
702               break;
703
704             default:
705               gold_unreachable();
706             }
707         }
708
709       pwrite += reloc_size;
710     }
711
712   gold_assert(static_cast<section_size_type>(pwrite - reloc_view)
713               == reloc_view_size);
714 }
715
716 } // End namespace gold.
717
718 #endif // !defined(GOLD_TARGET_RELOC_H)