xref: /netbsd/external/gpl3/gdb.old/dist/gold/symtab.cc (revision 56bb7041)
1 // symtab.cc -- the gold symbol table
2 
3 // Copyright (C) 2006-2020 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 #include "gold.h"
24 
25 #include <cstring>
26 #include <stdint.h>
27 #include <algorithm>
28 #include <set>
29 #include <string>
30 #include <utility>
31 #include "demangle.h"
32 
33 #include "gc.h"
34 #include "object.h"
35 #include "dwarf_reader.h"
36 #include "dynobj.h"
37 #include "output.h"
38 #include "target.h"
39 #include "workqueue.h"
40 #include "symtab.h"
41 #include "script.h"
42 #include "plugin.h"
43 #include "incremental.h"
44 
45 namespace gold
46 {
47 
48 // Class Symbol.
49 
50 // Initialize fields in Symbol.  This initializes everything except
51 // u1_, u2_ and source_.
52 
53 void
init_fields(const char * name,const char * version,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis)54 Symbol::init_fields(const char* name, const char* version,
55 		    elfcpp::STT type, elfcpp::STB binding,
56 		    elfcpp::STV visibility, unsigned char nonvis)
57 {
58   this->name_ = name;
59   this->version_ = version;
60   this->symtab_index_ = 0;
61   this->dynsym_index_ = 0;
62   this->got_offsets_.init();
63   this->plt_offset_ = -1U;
64   this->type_ = type;
65   this->binding_ = binding;
66   this->visibility_ = visibility;
67   this->nonvis_ = nonvis;
68   this->is_def_ = false;
69   this->is_forwarder_ = false;
70   this->has_alias_ = false;
71   this->needs_dynsym_entry_ = false;
72   this->in_reg_ = false;
73   this->in_dyn_ = false;
74   this->has_warning_ = false;
75   this->is_copied_from_dynobj_ = false;
76   this->is_forced_local_ = false;
77   this->is_ordinary_shndx_ = false;
78   this->in_real_elf_ = false;
79   this->is_defined_in_discarded_section_ = false;
80   this->undef_binding_set_ = false;
81   this->undef_binding_weak_ = false;
82   this->is_predefined_ = false;
83   this->is_protected_ = false;
84   this->non_zero_localentry_ = false;
85 }
86 
87 // Return the demangled version of the symbol's name, but only
88 // if the --demangle flag was set.
89 
90 static std::string
demangle(const char * name)91 demangle(const char* name)
92 {
93   if (!parameters->options().do_demangle())
94     return name;
95 
96   // cplus_demangle allocates memory for the result it returns,
97   // and returns NULL if the name is already demangled.
98   char* demangled_name = cplus_demangle(name, DMGL_ANSI | DMGL_PARAMS);
99   if (demangled_name == NULL)
100     return name;
101 
102   std::string retval(demangled_name);
103   free(demangled_name);
104   return retval;
105 }
106 
107 std::string
demangled_name() const108 Symbol::demangled_name() const
109 {
110   return demangle(this->name());
111 }
112 
113 // Initialize the fields in the base class Symbol for SYM in OBJECT.
114 
115 template<int size, bool big_endian>
116 void
init_base_object(const char * name,const char * version,Object * object,const elfcpp::Sym<size,big_endian> & sym,unsigned int st_shndx,bool is_ordinary)117 Symbol::init_base_object(const char* name, const char* version, Object* object,
118 			 const elfcpp::Sym<size, big_endian>& sym,
119 			 unsigned int st_shndx, bool is_ordinary)
120 {
121   this->init_fields(name, version, sym.get_st_type(), sym.get_st_bind(),
122 		    sym.get_st_visibility(), sym.get_st_nonvis());
123   this->u1_.object = object;
124   this->u2_.shndx = st_shndx;
125   this->is_ordinary_shndx_ = is_ordinary;
126   this->source_ = FROM_OBJECT;
127   this->in_reg_ = !object->is_dynamic();
128   this->in_dyn_ = object->is_dynamic();
129   this->in_real_elf_ = object->pluginobj() == NULL;
130 }
131 
132 // Initialize the fields in the base class Symbol for a symbol defined
133 // in an Output_data.
134 
135 void
init_base_output_data(const char * name,const char * version,Output_data * od,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis,bool offset_is_from_end,bool is_predefined)136 Symbol::init_base_output_data(const char* name, const char* version,
137 			      Output_data* od, elfcpp::STT type,
138 			      elfcpp::STB binding, elfcpp::STV visibility,
139 			      unsigned char nonvis, bool offset_is_from_end,
140 			      bool is_predefined)
141 {
142   this->init_fields(name, version, type, binding, visibility, nonvis);
143   this->u1_.output_data = od;
144   this->u2_.offset_is_from_end = offset_is_from_end;
145   this->source_ = IN_OUTPUT_DATA;
146   this->in_reg_ = true;
147   this->in_real_elf_ = true;
148   this->is_predefined_ = is_predefined;
149 }
150 
151 // Initialize the fields in the base class Symbol for a symbol defined
152 // in an Output_segment.
153 
154 void
init_base_output_segment(const char * name,const char * version,Output_segment * os,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis,Segment_offset_base offset_base,bool is_predefined)155 Symbol::init_base_output_segment(const char* name, const char* version,
156 				 Output_segment* os, elfcpp::STT type,
157 				 elfcpp::STB binding, elfcpp::STV visibility,
158 				 unsigned char nonvis,
159 				 Segment_offset_base offset_base,
160 				 bool is_predefined)
161 {
162   this->init_fields(name, version, type, binding, visibility, nonvis);
163   this->u1_.output_segment = os;
164   this->u2_.offset_base = offset_base;
165   this->source_ = IN_OUTPUT_SEGMENT;
166   this->in_reg_ = true;
167   this->in_real_elf_ = true;
168   this->is_predefined_ = is_predefined;
169 }
170 
171 // Initialize the fields in the base class Symbol for a symbol defined
172 // as a constant.
173 
174 void
init_base_constant(const char * name,const char * version,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis,bool is_predefined)175 Symbol::init_base_constant(const char* name, const char* version,
176 			   elfcpp::STT type, elfcpp::STB binding,
177 			   elfcpp::STV visibility, unsigned char nonvis,
178 			   bool is_predefined)
179 {
180   this->init_fields(name, version, type, binding, visibility, nonvis);
181   this->source_ = IS_CONSTANT;
182   this->in_reg_ = true;
183   this->in_real_elf_ = true;
184   this->is_predefined_ = is_predefined;
185 }
186 
187 // Initialize the fields in the base class Symbol for an undefined
188 // symbol.
189 
190 void
init_base_undefined(const char * name,const char * version,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis)191 Symbol::init_base_undefined(const char* name, const char* version,
192 			    elfcpp::STT type, elfcpp::STB binding,
193 			    elfcpp::STV visibility, unsigned char nonvis)
194 {
195   this->init_fields(name, version, type, binding, visibility, nonvis);
196   this->dynsym_index_ = -1U;
197   this->source_ = IS_UNDEFINED;
198   this->in_reg_ = true;
199   this->in_real_elf_ = true;
200 }
201 
202 // Allocate a common symbol in the base.
203 
204 void
allocate_base_common(Output_data * od)205 Symbol::allocate_base_common(Output_data* od)
206 {
207   gold_assert(this->is_common());
208   this->source_ = IN_OUTPUT_DATA;
209   this->u1_.output_data = od;
210   this->u2_.offset_is_from_end = false;
211 }
212 
213 // Initialize the fields in Sized_symbol for SYM in OBJECT.
214 
215 template<int size>
216 template<bool big_endian>
217 void
init_object(const char * name,const char * version,Object * object,const elfcpp::Sym<size,big_endian> & sym,unsigned int st_shndx,bool is_ordinary)218 Sized_symbol<size>::init_object(const char* name, const char* version,
219 				Object* object,
220 				const elfcpp::Sym<size, big_endian>& sym,
221 				unsigned int st_shndx, bool is_ordinary)
222 {
223   this->init_base_object(name, version, object, sym, st_shndx, is_ordinary);
224   this->value_ = sym.get_st_value();
225   this->symsize_ = sym.get_st_size();
226 }
227 
228 // Initialize the fields in Sized_symbol for a symbol defined in an
229 // Output_data.
230 
231 template<int size>
232 void
init_output_data(const char * name,const char * version,Output_data * od,Value_type value,Size_type symsize,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis,bool offset_is_from_end,bool is_predefined)233 Sized_symbol<size>::init_output_data(const char* name, const char* version,
234 				     Output_data* od, Value_type value,
235 				     Size_type symsize, elfcpp::STT type,
236 				     elfcpp::STB binding,
237 				     elfcpp::STV visibility,
238 				     unsigned char nonvis,
239 				     bool offset_is_from_end,
240 				     bool is_predefined)
241 {
242   this->init_base_output_data(name, version, od, type, binding, visibility,
243 			      nonvis, offset_is_from_end, is_predefined);
244   this->value_ = value;
245   this->symsize_ = symsize;
246 }
247 
248 // Initialize the fields in Sized_symbol for a symbol defined in an
249 // Output_segment.
250 
251 template<int size>
252 void
init_output_segment(const char * name,const char * version,Output_segment * os,Value_type value,Size_type symsize,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis,Segment_offset_base offset_base,bool is_predefined)253 Sized_symbol<size>::init_output_segment(const char* name, const char* version,
254 					Output_segment* os, Value_type value,
255 					Size_type symsize, elfcpp::STT type,
256 					elfcpp::STB binding,
257 					elfcpp::STV visibility,
258 					unsigned char nonvis,
259 					Segment_offset_base offset_base,
260 					bool is_predefined)
261 {
262   this->init_base_output_segment(name, version, os, type, binding, visibility,
263 				 nonvis, offset_base, is_predefined);
264   this->value_ = value;
265   this->symsize_ = symsize;
266 }
267 
268 // Initialize the fields in Sized_symbol for a symbol defined as a
269 // constant.
270 
271 template<int size>
272 void
init_constant(const char * name,const char * version,Value_type value,Size_type symsize,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis,bool is_predefined)273 Sized_symbol<size>::init_constant(const char* name, const char* version,
274 				  Value_type value, Size_type symsize,
275 				  elfcpp::STT type, elfcpp::STB binding,
276 				  elfcpp::STV visibility, unsigned char nonvis,
277 				  bool is_predefined)
278 {
279   this->init_base_constant(name, version, type, binding, visibility, nonvis,
280 			   is_predefined);
281   this->value_ = value;
282   this->symsize_ = symsize;
283 }
284 
285 // Initialize the fields in Sized_symbol for an undefined symbol.
286 
287 template<int size>
288 void
init_undefined(const char * name,const char * version,Value_type value,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis)289 Sized_symbol<size>::init_undefined(const char* name, const char* version,
290 				   Value_type value, elfcpp::STT type,
291 				   elfcpp::STB binding, elfcpp::STV visibility,
292 				   unsigned char nonvis)
293 {
294   this->init_base_undefined(name, version, type, binding, visibility, nonvis);
295   this->value_ = value;
296   this->symsize_ = 0;
297 }
298 
299 // Return an allocated string holding the symbol's name as
300 // name@version.  This is used for relocatable links.
301 
302 std::string
versioned_name() const303 Symbol::versioned_name() const
304 {
305   gold_assert(this->version_ != NULL);
306   std::string ret = this->name_;
307   ret.push_back('@');
308   if (this->is_def_)
309     ret.push_back('@');
310   ret += this->version_;
311   return ret;
312 }
313 
314 // Return true if SHNDX represents a common symbol.
315 
316 bool
is_common_shndx(unsigned int shndx)317 Symbol::is_common_shndx(unsigned int shndx)
318 {
319   return (shndx == elfcpp::SHN_COMMON
320 	  || shndx == parameters->target().small_common_shndx()
321 	  || shndx == parameters->target().large_common_shndx());
322 }
323 
324 // Allocate a common symbol.
325 
326 template<int size>
327 void
allocate_common(Output_data * od,Value_type value)328 Sized_symbol<size>::allocate_common(Output_data* od, Value_type value)
329 {
330   this->allocate_base_common(od);
331   this->value_ = value;
332 }
333 
334 // The ""'s around str ensure str is a string literal, so sizeof works.
335 #define strprefix(var, str)   (strncmp(var, str, sizeof("" str "") - 1) == 0)
336 
337 // Return true if this symbol should be added to the dynamic symbol
338 // table.
339 
340 bool
should_add_dynsym_entry(Symbol_table * symtab) const341 Symbol::should_add_dynsym_entry(Symbol_table* symtab) const
342 {
343   // If the symbol is only present on plugin files, the plugin decided we
344   // don't need it.
345   if (!this->in_real_elf())
346     return false;
347 
348   // If the symbol is used by a dynamic relocation, we need to add it.
349   if (this->needs_dynsym_entry())
350     return true;
351 
352   // If this symbol's section is not added, the symbol need not be added.
353   // The section may have been GCed.  Note that export_dynamic is being
354   // overridden here.  This should not be done for shared objects.
355   if (parameters->options().gc_sections()
356       && !parameters->options().shared()
357       && this->source() == Symbol::FROM_OBJECT
358       && !this->object()->is_dynamic())
359     {
360       Relobj* relobj = static_cast<Relobj*>(this->object());
361       bool is_ordinary;
362       unsigned int shndx = this->shndx(&is_ordinary);
363       if (is_ordinary && shndx != elfcpp::SHN_UNDEF
364           && !relobj->is_section_included(shndx)
365           && !symtab->is_section_folded(relobj, shndx))
366         return false;
367     }
368 
369   // If the symbol was forced dynamic in a --dynamic-list file
370   // or an --export-dynamic-symbol option, add it.
371   if (!this->is_from_dynobj()
372       && (parameters->options().in_dynamic_list(this->name())
373 	  || parameters->options().is_export_dynamic_symbol(this->name())))
374     {
375       if (!this->is_forced_local())
376         return true;
377       gold_warning(_("Cannot export local symbol '%s'"),
378 		   this->demangled_name().c_str());
379       return false;
380     }
381 
382   // If the symbol was forced local in a version script, do not add it.
383   if (this->is_forced_local())
384     return false;
385 
386   // If dynamic-list-data was specified, add any STT_OBJECT.
387   if (parameters->options().dynamic_list_data()
388       && !this->is_from_dynobj()
389       && this->type() == elfcpp::STT_OBJECT)
390     return true;
391 
392   // If --dynamic-list-cpp-new was specified, add any new/delete symbol.
393   // If --dynamic-list-cpp-typeinfo was specified, add any typeinfo symbols.
394   if ((parameters->options().dynamic_list_cpp_new()
395        || parameters->options().dynamic_list_cpp_typeinfo())
396       && !this->is_from_dynobj())
397     {
398       // TODO(csilvers): We could probably figure out if we're an operator
399       //                 new/delete or typeinfo without the need to demangle.
400       char* demangled_name = cplus_demangle(this->name(),
401                                             DMGL_ANSI | DMGL_PARAMS);
402       if (demangled_name == NULL)
403         {
404           // Not a C++ symbol, so it can't satisfy these flags
405         }
406       else if (parameters->options().dynamic_list_cpp_new()
407                && (strprefix(demangled_name, "operator new")
408                    || strprefix(demangled_name, "operator delete")))
409         {
410           free(demangled_name);
411           return true;
412         }
413       else if (parameters->options().dynamic_list_cpp_typeinfo()
414                && (strprefix(demangled_name, "typeinfo name for")
415                    || strprefix(demangled_name, "typeinfo for")))
416         {
417           free(demangled_name);
418           return true;
419         }
420       else
421         free(demangled_name);
422     }
423 
424   // If exporting all symbols or building a shared library,
425   // or the symbol should be globally unique (GNU_UNIQUE),
426   // and the symbol is defined in a regular object and is
427   // externally visible, we need to add it.
428   if ((parameters->options().export_dynamic()
429        || parameters->options().shared()
430        || (parameters->options().gnu_unique()
431            && this->binding() == elfcpp::STB_GNU_UNIQUE))
432       && !this->is_from_dynobj()
433       && !this->is_undefined()
434       && this->is_externally_visible())
435     return true;
436 
437   return false;
438 }
439 
440 // Return true if the final value of this symbol is known at link
441 // time.
442 
443 bool
final_value_is_known() const444 Symbol::final_value_is_known() const
445 {
446   // If we are not generating an executable, then no final values are
447   // known, since they will change at runtime, with the exception of
448   // TLS symbols in a position-independent executable.
449   if ((parameters->options().output_is_position_independent()
450        || parameters->options().relocatable())
451       && !(this->type() == elfcpp::STT_TLS
452            && parameters->options().pie()))
453     return false;
454 
455   // If the symbol is not from an object file, and is not undefined,
456   // then it is defined, and known.
457   if (this->source_ != FROM_OBJECT)
458     {
459       if (this->source_ != IS_UNDEFINED)
460 	return true;
461     }
462   else
463     {
464       // If the symbol is from a dynamic object, then the final value
465       // is not known.
466       if (this->object()->is_dynamic())
467 	return false;
468 
469       // If the symbol is not undefined (it is defined or common),
470       // then the final value is known.
471       if (!this->is_undefined())
472 	return true;
473     }
474 
475   // If the symbol is undefined, then whether the final value is known
476   // depends on whether we are doing a static link.  If we are doing a
477   // dynamic link, then the final value could be filled in at runtime.
478   // This could reasonably be the case for a weak undefined symbol.
479   return parameters->doing_static_link();
480 }
481 
482 // Return the output section where this symbol is defined.
483 
484 Output_section*
output_section() const485 Symbol::output_section() const
486 {
487   switch (this->source_)
488     {
489     case FROM_OBJECT:
490       {
491 	unsigned int shndx = this->u2_.shndx;
492 	if (shndx != elfcpp::SHN_UNDEF && this->is_ordinary_shndx_)
493 	  {
494 	    gold_assert(!this->u1_.object->is_dynamic());
495 	    gold_assert(this->u1_.object->pluginobj() == NULL);
496 	    Relobj* relobj = static_cast<Relobj*>(this->u1_.object);
497 	    return relobj->output_section(shndx);
498 	  }
499 	return NULL;
500       }
501 
502     case IN_OUTPUT_DATA:
503       return this->u1_.output_data->output_section();
504 
505     case IN_OUTPUT_SEGMENT:
506     case IS_CONSTANT:
507     case IS_UNDEFINED:
508       return NULL;
509 
510     default:
511       gold_unreachable();
512     }
513 }
514 
515 // Set the symbol's output section.  This is used for symbols defined
516 // in scripts.  This should only be called after the symbol table has
517 // been finalized.
518 
519 void
set_output_section(Output_section * os)520 Symbol::set_output_section(Output_section* os)
521 {
522   switch (this->source_)
523     {
524     case FROM_OBJECT:
525     case IN_OUTPUT_DATA:
526       gold_assert(this->output_section() == os);
527       break;
528     case IS_CONSTANT:
529       this->source_ = IN_OUTPUT_DATA;
530       this->u1_.output_data = os;
531       this->u2_.offset_is_from_end = false;
532       break;
533     case IN_OUTPUT_SEGMENT:
534     case IS_UNDEFINED:
535     default:
536       gold_unreachable();
537     }
538 }
539 
540 // Set the symbol's output segment.  This is used for pre-defined
541 // symbols whose segments aren't known until after layout is done
542 // (e.g., __ehdr_start).
543 
544 void
set_output_segment(Output_segment * os,Segment_offset_base base)545 Symbol::set_output_segment(Output_segment* os, Segment_offset_base base)
546 {
547   gold_assert(this->is_predefined_);
548   this->source_ = IN_OUTPUT_SEGMENT;
549   this->u1_.output_segment = os;
550   this->u2_.offset_base = base;
551 }
552 
553 // Set the symbol to undefined.  This is used for pre-defined
554 // symbols whose segments aren't known until after layout is done
555 // (e.g., __ehdr_start).
556 
557 void
set_undefined()558 Symbol::set_undefined()
559 {
560   this->source_ = IS_UNDEFINED;
561   this->is_predefined_ = false;
562 }
563 
564 // Class Symbol_table.
565 
Symbol_table(unsigned int count,const Version_script_info & version_script)566 Symbol_table::Symbol_table(unsigned int count,
567                            const Version_script_info& version_script)
568   : saw_undefined_(0), offset_(0), has_gnu_output_(false), table_(count),
569     namepool_(), forwarders_(), commons_(), tls_commons_(), small_commons_(),
570     large_commons_(), forced_locals_(), warnings_(),
571     version_script_(version_script), gc_(NULL), icf_(NULL),
572     target_symbols_()
573 {
574   namepool_.reserve(count);
575 }
576 
~Symbol_table()577 Symbol_table::~Symbol_table()
578 {
579 }
580 
581 // The symbol table key equality function.  This is called with
582 // Stringpool keys.
583 
584 inline bool
operator ()(const Symbol_table_key & k1,const Symbol_table_key & k2) const585 Symbol_table::Symbol_table_eq::operator()(const Symbol_table_key& k1,
586 					  const Symbol_table_key& k2) const
587 {
588   return k1.first == k2.first && k1.second == k2.second;
589 }
590 
591 bool
is_section_folded(Relobj * obj,unsigned int shndx) const592 Symbol_table::is_section_folded(Relobj* obj, unsigned int shndx) const
593 {
594   return (parameters->options().icf_enabled()
595           && this->icf_->is_section_folded(obj, shndx));
596 }
597 
598 // For symbols that have been listed with a -u or --export-dynamic-symbol
599 // option, add them to the work list to avoid gc'ing them.
600 
601 void
gc_mark_undef_symbols(Layout * layout)602 Symbol_table::gc_mark_undef_symbols(Layout* layout)
603 {
604   for (options::String_set::const_iterator p =
605 	 parameters->options().undefined_begin();
606        p != parameters->options().undefined_end();
607        ++p)
608     {
609       const char* name = p->c_str();
610       Symbol* sym = this->lookup(name);
611       gold_assert(sym != NULL);
612       if (sym->source() == Symbol::FROM_OBJECT
613           && !sym->object()->is_dynamic())
614         {
615 	  this->gc_mark_symbol(sym);
616         }
617     }
618 
619   for (options::String_set::const_iterator p =
620 	 parameters->options().export_dynamic_symbol_begin();
621        p != parameters->options().export_dynamic_symbol_end();
622        ++p)
623     {
624       const char* name = p->c_str();
625       Symbol* sym = this->lookup(name);
626       // It's not an error if a symbol named by --export-dynamic-symbol
627       // is undefined.
628       if (sym != NULL
629 	  && sym->source() == Symbol::FROM_OBJECT
630           && !sym->object()->is_dynamic())
631         {
632 	  this->gc_mark_symbol(sym);
633         }
634     }
635 
636   for (Script_options::referenced_const_iterator p =
637 	 layout->script_options()->referenced_begin();
638        p != layout->script_options()->referenced_end();
639        ++p)
640     {
641       Symbol* sym = this->lookup(p->c_str());
642       gold_assert(sym != NULL);
643       if (sym->source() == Symbol::FROM_OBJECT
644 	  && !sym->object()->is_dynamic())
645 	{
646 	  this->gc_mark_symbol(sym);
647 	}
648     }
649 }
650 
651 void
gc_mark_symbol(Symbol * sym)652 Symbol_table::gc_mark_symbol(Symbol* sym)
653 {
654   // Add the object and section to the work list.
655   bool is_ordinary;
656   unsigned int shndx = sym->shndx(&is_ordinary);
657   if (is_ordinary && shndx != elfcpp::SHN_UNDEF && !sym->object()->is_dynamic())
658     {
659       gold_assert(this->gc_!= NULL);
660       Relobj* relobj = static_cast<Relobj*>(sym->object());
661       this->gc_->worklist().push_back(Section_id(relobj, shndx));
662     }
663   parameters->target().gc_mark_symbol(this, sym);
664 }
665 
666 // When doing garbage collection, keep symbols that have been seen in
667 // dynamic objects.
668 inline void
gc_mark_dyn_syms(Symbol * sym)669 Symbol_table::gc_mark_dyn_syms(Symbol* sym)
670 {
671   if (sym->in_dyn() && sym->source() == Symbol::FROM_OBJECT
672       && !sym->object()->is_dynamic())
673     this->gc_mark_symbol(sym);
674 }
675 
676 // Make TO a symbol which forwards to FROM.
677 
678 void
make_forwarder(Symbol * from,Symbol * to)679 Symbol_table::make_forwarder(Symbol* from, Symbol* to)
680 {
681   gold_assert(from != to);
682   gold_assert(!from->is_forwarder() && !to->is_forwarder());
683   this->forwarders_[from] = to;
684   from->set_forwarder();
685 }
686 
687 // Resolve the forwards from FROM, returning the real symbol.
688 
689 Symbol*
resolve_forwards(const Symbol * from) const690 Symbol_table::resolve_forwards(const Symbol* from) const
691 {
692   gold_assert(from->is_forwarder());
693   Unordered_map<const Symbol*, Symbol*>::const_iterator p =
694     this->forwarders_.find(from);
695   gold_assert(p != this->forwarders_.end());
696   return p->second;
697 }
698 
699 // Look up a symbol by name.
700 
701 Symbol*
lookup(const char * name,const char * version) const702 Symbol_table::lookup(const char* name, const char* version) const
703 {
704   Stringpool::Key name_key;
705   name = this->namepool_.find(name, &name_key);
706   if (name == NULL)
707     return NULL;
708 
709   Stringpool::Key version_key = 0;
710   if (version != NULL)
711     {
712       version = this->namepool_.find(version, &version_key);
713       if (version == NULL)
714 	return NULL;
715     }
716 
717   Symbol_table_key key(name_key, version_key);
718   Symbol_table::Symbol_table_type::const_iterator p = this->table_.find(key);
719   if (p == this->table_.end())
720     return NULL;
721   return p->second;
722 }
723 
724 // Resolve a Symbol with another Symbol.  This is only used in the
725 // unusual case where there are references to both an unversioned
726 // symbol and a symbol with a version, and we then discover that that
727 // version is the default version.  Because this is unusual, we do
728 // this the slow way, by converting back to an ELF symbol.
729 
730 template<int size, bool big_endian>
731 void
resolve(Sized_symbol<size> * to,const Sized_symbol<size> * from)732 Symbol_table::resolve(Sized_symbol<size>* to, const Sized_symbol<size>* from)
733 {
734   unsigned char buf[elfcpp::Elf_sizes<size>::sym_size];
735   elfcpp::Sym_write<size, big_endian> esym(buf);
736   // We don't bother to set the st_name or the st_shndx field.
737   esym.put_st_value(from->value());
738   esym.put_st_size(from->symsize());
739   esym.put_st_info(from->binding(), from->type());
740   esym.put_st_other(from->visibility(), from->nonvis());
741   bool is_ordinary;
742   unsigned int shndx = from->shndx(&is_ordinary);
743   this->resolve(to, esym.sym(), shndx, is_ordinary, shndx, from->object(),
744 		from->version(), true);
745   if (from->in_reg())
746     to->set_in_reg();
747   if (from->in_dyn())
748     to->set_in_dyn();
749   if (parameters->options().gc_sections())
750     this->gc_mark_dyn_syms(to);
751 }
752 
753 // Record that a symbol is forced to be local by a version script or
754 // by visibility.
755 
756 void
force_local(Symbol * sym)757 Symbol_table::force_local(Symbol* sym)
758 {
759   if (!sym->is_defined() && !sym->is_common())
760     return;
761   if (sym->is_forced_local())
762     {
763       // We already got this one.
764       return;
765     }
766   sym->set_is_forced_local();
767   this->forced_locals_.push_back(sym);
768 }
769 
770 // Adjust NAME for wrapping, and update *NAME_KEY if necessary.  This
771 // is only called for undefined symbols, when at least one --wrap
772 // option was used.
773 
774 const char*
wrap_symbol(const char * name,Stringpool::Key * name_key)775 Symbol_table::wrap_symbol(const char* name, Stringpool::Key* name_key)
776 {
777   // For some targets, we need to ignore a specific character when
778   // wrapping, and add it back later.
779   char prefix = '\0';
780   if (name[0] == parameters->target().wrap_char())
781     {
782       prefix = name[0];
783       ++name;
784     }
785 
786   if (parameters->options().is_wrap(name))
787     {
788       // Turn NAME into __wrap_NAME.
789       std::string s;
790       if (prefix != '\0')
791 	s += prefix;
792       s += "__wrap_";
793       s += name;
794 
795       // This will give us both the old and new name in NAMEPOOL_, but
796       // that is OK.  Only the versions we need will wind up in the
797       // real string table in the output file.
798       return this->namepool_.add(s.c_str(), true, name_key);
799     }
800 
801   const char* const real_prefix = "__real_";
802   const size_t real_prefix_length = strlen(real_prefix);
803   if (strncmp(name, real_prefix, real_prefix_length) == 0
804       && parameters->options().is_wrap(name + real_prefix_length))
805     {
806       // Turn __real_NAME into NAME.
807       std::string s;
808       if (prefix != '\0')
809 	s += prefix;
810       s += name + real_prefix_length;
811       return this->namepool_.add(s.c_str(), true, name_key);
812     }
813 
814   return name;
815 }
816 
817 // This is called when we see a symbol NAME/VERSION, and the symbol
818 // already exists in the symbol table, and VERSION is marked as being
819 // the default version.  SYM is the NAME/VERSION symbol we just added.
820 // DEFAULT_IS_NEW is true if this is the first time we have seen the
821 // symbol NAME/NULL.  PDEF points to the entry for NAME/NULL.
822 
823 template<int size, bool big_endian>
824 void
define_default_version(Sized_symbol<size> * sym,bool default_is_new,Symbol_table_type::iterator pdef)825 Symbol_table::define_default_version(Sized_symbol<size>* sym,
826 				     bool default_is_new,
827 				     Symbol_table_type::iterator pdef)
828 {
829   if (default_is_new)
830     {
831       // This is the first time we have seen NAME/NULL.  Make
832       // NAME/NULL point to NAME/VERSION, and mark SYM as the default
833       // version.
834       pdef->second = sym;
835       sym->set_is_default();
836     }
837   else if (pdef->second == sym)
838     {
839       // NAME/NULL already points to NAME/VERSION.  Don't mark the
840       // symbol as the default if it is not already the default.
841     }
842   else
843     {
844       // This is the unfortunate case where we already have entries
845       // for both NAME/VERSION and NAME/NULL.  We now see a symbol
846       // NAME/VERSION where VERSION is the default version.  We have
847       // already resolved this new symbol with the existing
848       // NAME/VERSION symbol.
849 
850       // It's possible that NAME/NULL and NAME/VERSION are both
851       // defined in regular objects.  This can only happen if one
852       // object file defines foo and another defines foo@@ver.  This
853       // is somewhat obscure, but we call it a multiple definition
854       // error.
855 
856       // It's possible that NAME/NULL actually has a version, in which
857       // case it won't be the same as VERSION.  This happens with
858       // ver_test_7.so in the testsuite for the symbol t2_2.  We see
859       // t2_2@@VER2, so we define both t2_2/VER2 and t2_2/NULL.  We
860       // then see an unadorned t2_2 in an object file and give it
861       // version VER1 from the version script.  This looks like a
862       // default definition for VER1, so it looks like we should merge
863       // t2_2/NULL with t2_2/VER1.  That doesn't make sense, but it's
864       // not obvious that this is an error, either.  So we just punt.
865 
866       // If one of the symbols has non-default visibility, and the
867       // other is defined in a shared object, then they are different
868       // symbols.
869 
870       // If the two symbols are from different shared objects,
871       // they are different symbols.
872 
873       // Otherwise, we just resolve the symbols as though they were
874       // the same.
875 
876       if (pdef->second->version() != NULL)
877 	gold_assert(pdef->second->version() != sym->version());
878       else if (sym->visibility() != elfcpp::STV_DEFAULT
879 	       && pdef->second->is_from_dynobj())
880 	;
881       else if (pdef->second->visibility() != elfcpp::STV_DEFAULT
882 	       && sym->is_from_dynobj())
883 	;
884       else if (pdef->second->is_from_dynobj()
885 	       && sym->is_from_dynobj()
886 	       && pdef->second->is_defined()
887 	       && pdef->second->object() != sym->object())
888         ;
889       else
890 	{
891 	  const Sized_symbol<size>* symdef;
892 	  symdef = this->get_sized_symbol<size>(pdef->second);
893 	  Symbol_table::resolve<size, big_endian>(sym, symdef);
894 	  this->make_forwarder(pdef->second, sym);
895 	  pdef->second = sym;
896 	  sym->set_is_default();
897 	}
898     }
899 }
900 
901 // Add one symbol from OBJECT to the symbol table.  NAME is symbol
902 // name and VERSION is the version; both are canonicalized.  DEF is
903 // whether this is the default version.  ST_SHNDX is the symbol's
904 // section index; IS_ORDINARY is whether this is a normal section
905 // rather than a special code.
906 
907 // If IS_DEFAULT_VERSION is true, then this is the definition of a
908 // default version of a symbol.  That means that any lookup of
909 // NAME/NULL and any lookup of NAME/VERSION should always return the
910 // same symbol.  This is obvious for references, but in particular we
911 // want to do this for definitions: overriding NAME/NULL should also
912 // override NAME/VERSION.  If we don't do that, it would be very hard
913 // to override functions in a shared library which uses versioning.
914 
915 // We implement this by simply making both entries in the hash table
916 // point to the same Symbol structure.  That is easy enough if this is
917 // the first time we see NAME/NULL or NAME/VERSION, but it is possible
918 // that we have seen both already, in which case they will both have
919 // independent entries in the symbol table.  We can't simply change
920 // the symbol table entry, because we have pointers to the entries
921 // attached to the object files.  So we mark the entry attached to the
922 // object file as a forwarder, and record it in the forwarders_ map.
923 // Note that entries in the hash table will never be marked as
924 // forwarders.
925 //
926 // ORIG_ST_SHNDX and ST_SHNDX are almost always the same.
927 // ORIG_ST_SHNDX is the section index in the input file, or SHN_UNDEF
928 // for a special section code.  ST_SHNDX may be modified if the symbol
929 // is defined in a section being discarded.
930 
931 template<int size, bool big_endian>
932 Sized_symbol<size>*
add_from_object(Object * object,const char * name,Stringpool::Key name_key,const char * version,Stringpool::Key version_key,bool is_default_version,const elfcpp::Sym<size,big_endian> & sym,unsigned int st_shndx,bool is_ordinary,unsigned int orig_st_shndx)933 Symbol_table::add_from_object(Object* object,
934 			      const char* name,
935 			      Stringpool::Key name_key,
936 			      const char* version,
937 			      Stringpool::Key version_key,
938 			      bool is_default_version,
939 			      const elfcpp::Sym<size, big_endian>& sym,
940 			      unsigned int st_shndx,
941 			      bool is_ordinary,
942 			      unsigned int orig_st_shndx)
943 {
944   // Print a message if this symbol is being traced.
945   if (parameters->options().is_trace_symbol(name))
946     {
947       if (orig_st_shndx == elfcpp::SHN_UNDEF)
948         gold_info(_("%s: reference to %s"), object->name().c_str(), name);
949       else
950         gold_info(_("%s: definition of %s"), object->name().c_str(), name);
951     }
952 
953   // For an undefined symbol, we may need to adjust the name using
954   // --wrap.
955   if (orig_st_shndx == elfcpp::SHN_UNDEF
956       && parameters->options().any_wrap())
957     {
958       const char* wrap_name = this->wrap_symbol(name, &name_key);
959       if (wrap_name != name)
960 	{
961 	  // If we see a reference to malloc with version GLIBC_2.0,
962 	  // and we turn it into a reference to __wrap_malloc, then we
963 	  // discard the version number.  Otherwise the user would be
964 	  // required to specify the correct version for
965 	  // __wrap_malloc.
966 	  version = NULL;
967 	  version_key = 0;
968 	  name = wrap_name;
969 	}
970     }
971 
972   Symbol* const snull = NULL;
973   std::pair<typename Symbol_table_type::iterator, bool> ins =
974     this->table_.insert(std::make_pair(std::make_pair(name_key, version_key),
975 				       snull));
976 
977   std::pair<typename Symbol_table_type::iterator, bool> insdefault =
978     std::make_pair(this->table_.end(), false);
979   if (is_default_version)
980     {
981       const Stringpool::Key vnull_key = 0;
982       insdefault = this->table_.insert(std::make_pair(std::make_pair(name_key,
983 								     vnull_key),
984 						      snull));
985     }
986 
987   // ins.first: an iterator, which is a pointer to a pair.
988   // ins.first->first: the key (a pair of name and version).
989   // ins.first->second: the value (Symbol*).
990   // ins.second: true if new entry was inserted, false if not.
991 
992   Sized_symbol<size>* ret = NULL;
993   bool was_undefined_in_reg;
994   bool was_common;
995   if (!ins.second)
996     {
997       // We already have an entry for NAME/VERSION.
998       ret = this->get_sized_symbol<size>(ins.first->second);
999       gold_assert(ret != NULL);
1000 
1001       was_undefined_in_reg = ret->is_undefined() && ret->in_reg();
1002       // Commons from plugins are just placeholders.
1003       was_common = ret->is_common() && ret->object()->pluginobj() == NULL;
1004 
1005       this->resolve(ret, sym, st_shndx, is_ordinary, orig_st_shndx, object,
1006 		    version, is_default_version);
1007       if (parameters->options().gc_sections())
1008         this->gc_mark_dyn_syms(ret);
1009 
1010       if (is_default_version)
1011 	this->define_default_version<size, big_endian>(ret, insdefault.second,
1012 						       insdefault.first);
1013       else
1014 	{
1015 	  bool dummy;
1016 	  if (version != NULL
1017 	      && ret->source() == Symbol::FROM_OBJECT
1018 	      && ret->object() == object
1019 	      && is_ordinary
1020 	      && ret->shndx(&dummy) == st_shndx
1021 	      && ret->is_default())
1022 	    {
1023 	      // We have seen NAME/VERSION already, and marked it as the
1024 	      // default version, but now we see a definition for
1025 	      // NAME/VERSION that is not the default version. This can
1026 	      // happen when the assembler generates two symbols for
1027 	      // a symbol as a result of a ".symver foo,foo@VER"
1028 	      // directive. We see the first unversioned symbol and
1029 	      // we may mark it as the default version (from a
1030 	      // version script); then we see the second versioned
1031 	      // symbol and we need to override the first.
1032 	      // In any other case, the two symbols should have generated
1033 	      // a multiple definition error.
1034 	      // (See PR gold/18703.)
1035 	      ret->set_is_not_default();
1036 	      const Stringpool::Key vnull_key = 0;
1037 	      this->table_.erase(std::make_pair(name_key, vnull_key));
1038 	    }
1039 	}
1040     }
1041   else
1042     {
1043       // This is the first time we have seen NAME/VERSION.
1044       gold_assert(ins.first->second == NULL);
1045 
1046       if (is_default_version && !insdefault.second)
1047 	{
1048 	  // We already have an entry for NAME/NULL.  If we override
1049 	  // it, then change it to NAME/VERSION.
1050 	  ret = this->get_sized_symbol<size>(insdefault.first->second);
1051 
1052 	  // If the existing symbol already has a version,
1053 	  // don't override it with the new symbol.
1054 	  // This should only happen when the new symbol
1055 	  // is from a shared library.
1056 	  if (ret->version() != NULL)
1057 	    {
1058 	      if (!object->is_dynamic())
1059 	        {
1060 		  gold_warning(_("%s: conflicting default version definition"
1061 				 " for %s@@%s"),
1062 			       object->name().c_str(), name, version);
1063 		  if (ret->source() == Symbol::FROM_OBJECT)
1064 		    gold_info(_("%s: %s: previous definition of %s@@%s here"),
1065 			      program_name,
1066 			      ret->object()->name().c_str(),
1067 			      name, ret->version());
1068 	        }
1069 	      ret = NULL;
1070 	      is_default_version = false;
1071 	    }
1072 	  else
1073 	    {
1074 	      was_undefined_in_reg = ret->is_undefined() && ret->in_reg();
1075 	      // Commons from plugins are just placeholders.
1076 	      was_common = (ret->is_common()
1077 			    && ret->object()->pluginobj() == NULL);
1078 
1079 	      this->resolve(ret, sym, st_shndx, is_ordinary, orig_st_shndx,
1080 			    object, version, is_default_version);
1081 	      if (parameters->options().gc_sections())
1082 		this->gc_mark_dyn_syms(ret);
1083 	      ins.first->second = ret;
1084 	    }
1085 	}
1086 
1087       if (ret == NULL)
1088 	{
1089 	  was_undefined_in_reg = false;
1090 	  was_common = false;
1091 
1092 	  Sized_target<size, big_endian>* target =
1093 	    parameters->sized_target<size, big_endian>();
1094 	  if (!target->has_make_symbol())
1095 	    ret = new Sized_symbol<size>();
1096 	  else
1097 	    {
1098 	      ret = target->make_symbol(name, sym.get_st_type(), object,
1099 					st_shndx, sym.get_st_value());
1100 	      if (ret == NULL)
1101 		{
1102 		  // This means that we don't want a symbol table
1103 		  // entry after all.
1104 		  if (!is_default_version)
1105 		    this->table_.erase(ins.first);
1106 		  else
1107 		    {
1108 		      this->table_.erase(insdefault.first);
1109 		      // Inserting INSDEFAULT invalidated INS.
1110 		      this->table_.erase(std::make_pair(name_key,
1111 							version_key));
1112 		    }
1113 		  return NULL;
1114 		}
1115 	    }
1116 
1117 	  ret->init_object(name, version, object, sym, st_shndx, is_ordinary);
1118 
1119 	  ins.first->second = ret;
1120 	  if (is_default_version)
1121 	    {
1122 	      // This is the first time we have seen NAME/NULL.  Point
1123 	      // it at the new entry for NAME/VERSION.
1124 	      gold_assert(insdefault.second);
1125 	      insdefault.first->second = ret;
1126 	    }
1127 	}
1128 
1129       if (is_default_version)
1130 	ret->set_is_default();
1131     }
1132 
1133   // Record every time we see a new undefined symbol, to speed up archive
1134   // groups. We only care about symbols undefined in regular objects here
1135   // because undefined symbols only in dynamic objects should't trigger rescans.
1136   if (!was_undefined_in_reg && ret->is_undefined() && ret->in_reg())
1137     {
1138       ++this->saw_undefined_;
1139       if (parameters->options().has_plugins())
1140 	parameters->options().plugins()->new_undefined_symbol(ret);
1141     }
1142 
1143   // Keep track of common symbols, to speed up common symbol
1144   // allocation.  Don't record commons from plugin objects;
1145   // we need to wait until we see the real symbol in the
1146   // replacement file.
1147   if (!was_common && ret->is_common() && ret->object()->pluginobj() == NULL)
1148     {
1149       if (ret->type() == elfcpp::STT_TLS)
1150 	this->tls_commons_.push_back(ret);
1151       else if (!is_ordinary
1152 	       && st_shndx == parameters->target().small_common_shndx())
1153 	this->small_commons_.push_back(ret);
1154       else if (!is_ordinary
1155 	       && st_shndx == parameters->target().large_common_shndx())
1156 	this->large_commons_.push_back(ret);
1157       else
1158 	this->commons_.push_back(ret);
1159     }
1160 
1161   // If we're not doing a relocatable link, then any symbol with
1162   // hidden or internal visibility is local.
1163   if ((ret->visibility() == elfcpp::STV_HIDDEN
1164        || ret->visibility() == elfcpp::STV_INTERNAL)
1165       && (ret->binding() == elfcpp::STB_GLOBAL
1166 	  || ret->binding() == elfcpp::STB_GNU_UNIQUE
1167 	  || ret->binding() == elfcpp::STB_WEAK)
1168       && !parameters->options().relocatable())
1169     this->force_local(ret);
1170 
1171   return ret;
1172 }
1173 
1174 // Add all the symbols in a relocatable object to the hash table.
1175 
1176 template<int size, bool big_endian>
1177 void
add_from_relobj(Sized_relobj_file<size,big_endian> * relobj,const unsigned char * syms,size_t count,size_t symndx_offset,const char * sym_names,size_t sym_name_size,typename Sized_relobj_file<size,big_endian>::Symbols * sympointers,size_t * defined)1178 Symbol_table::add_from_relobj(
1179     Sized_relobj_file<size, big_endian>* relobj,
1180     const unsigned char* syms,
1181     size_t count,
1182     size_t symndx_offset,
1183     const char* sym_names,
1184     size_t sym_name_size,
1185     typename Sized_relobj_file<size, big_endian>::Symbols* sympointers,
1186     size_t* defined)
1187 {
1188   *defined = 0;
1189 
1190   gold_assert(size == parameters->target().get_size());
1191 
1192   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1193 
1194   const bool just_symbols = relobj->just_symbols();
1195 
1196   const unsigned char* p = syms;
1197   for (size_t i = 0; i < count; ++i, p += sym_size)
1198     {
1199       (*sympointers)[i] = NULL;
1200 
1201       elfcpp::Sym<size, big_endian> sym(p);
1202 
1203       unsigned int st_name = sym.get_st_name();
1204       if (st_name >= sym_name_size)
1205 	{
1206 	  relobj->error(_("bad global symbol name offset %u at %zu"),
1207 			st_name, i);
1208 	  continue;
1209 	}
1210 
1211       const char* name = sym_names + st_name;
1212 
1213       if (!parameters->options().relocatable()
1214 	  && name[0] == '_'
1215 	  && name[1] == '_'
1216 	  && strcmp (name + (name[2] == '_'), "__gnu_lto_slim") == 0)
1217         gold_info(_("%s: plugin needed to handle lto object"),
1218 		  relobj->name().c_str());
1219 
1220       bool is_ordinary;
1221       unsigned int st_shndx = relobj->adjust_sym_shndx(i + symndx_offset,
1222 						       sym.get_st_shndx(),
1223 						       &is_ordinary);
1224       unsigned int orig_st_shndx = st_shndx;
1225       if (!is_ordinary)
1226 	orig_st_shndx = elfcpp::SHN_UNDEF;
1227 
1228       if (st_shndx != elfcpp::SHN_UNDEF)
1229 	++*defined;
1230 
1231       // A symbol defined in a section which we are not including must
1232       // be treated as an undefined symbol.
1233       bool is_defined_in_discarded_section = false;
1234       if (st_shndx != elfcpp::SHN_UNDEF
1235 	  && is_ordinary
1236 	  && !relobj->is_section_included(st_shndx)
1237           && !this->is_section_folded(relobj, st_shndx))
1238 	{
1239 	  st_shndx = elfcpp::SHN_UNDEF;
1240 	  is_defined_in_discarded_section = true;
1241 	}
1242 
1243       // In an object file, an '@' in the name separates the symbol
1244       // name from the version name.  If there are two '@' characters,
1245       // this is the default version.
1246       const char* ver = strchr(name, '@');
1247       Stringpool::Key ver_key = 0;
1248       int namelen = 0;
1249       // IS_DEFAULT_VERSION: is the version default?
1250       // IS_FORCED_LOCAL: is the symbol forced local?
1251       bool is_default_version = false;
1252       bool is_forced_local = false;
1253 
1254       // FIXME: For incremental links, we don't store version information,
1255       // so we need to ignore version symbols for now.
1256       if (parameters->incremental_update() && ver != NULL)
1257 	{
1258 	  namelen = ver - name;
1259 	  ver = NULL;
1260 	}
1261 
1262       if (ver != NULL)
1263         {
1264           // The symbol name is of the form foo@VERSION or foo@@VERSION
1265           namelen = ver - name;
1266           ++ver;
1267 	  if (*ver == '@')
1268 	    {
1269 	      is_default_version = true;
1270 	      ++ver;
1271 	    }
1272 	  ver = this->namepool_.add(ver, true, &ver_key);
1273         }
1274       // We don't want to assign a version to an undefined symbol,
1275       // even if it is listed in the version script.  FIXME: What
1276       // about a common symbol?
1277       else
1278 	{
1279 	  namelen = strlen(name);
1280 	  if (!this->version_script_.empty()
1281 	      && st_shndx != elfcpp::SHN_UNDEF)
1282 	    {
1283 	      // The symbol name did not have a version, but the
1284 	      // version script may assign a version anyway.
1285 	      std::string version;
1286 	      bool is_global;
1287 	      if (this->version_script_.get_symbol_version(name, &version,
1288 							   &is_global))
1289 		{
1290 		  if (!is_global)
1291 		    is_forced_local = true;
1292 		  else if (!version.empty())
1293 		    {
1294 		      ver = this->namepool_.add_with_length(version.c_str(),
1295 							    version.length(),
1296 							    true,
1297 							    &ver_key);
1298 		      is_default_version = true;
1299 		    }
1300 		}
1301 	    }
1302 	}
1303 
1304       elfcpp::Sym<size, big_endian>* psym = &sym;
1305       unsigned char symbuf[sym_size];
1306       elfcpp::Sym<size, big_endian> sym2(symbuf);
1307       if (just_symbols)
1308 	{
1309 	  memcpy(symbuf, p, sym_size);
1310 	  elfcpp::Sym_write<size, big_endian> sw(symbuf);
1311 	  if (orig_st_shndx != elfcpp::SHN_UNDEF
1312 	      && is_ordinary
1313 	      && relobj->e_type() == elfcpp::ET_REL)
1314 	    {
1315 	      // Symbol values in relocatable object files are section
1316 	      // relative.  This is normally what we want, but since here
1317 	      // we are converting the symbol to absolute we need to add
1318 	      // the section address.  The section address in an object
1319 	      // file is normally zero, but people can use a linker
1320 	      // script to change it.
1321 	      sw.put_st_value(sym.get_st_value()
1322 			      + relobj->section_address(orig_st_shndx));
1323 	    }
1324 	  st_shndx = elfcpp::SHN_ABS;
1325 	  is_ordinary = false;
1326 	  psym = &sym2;
1327 	}
1328 
1329       // Fix up visibility if object has no-export set.
1330       if (relobj->no_export()
1331 	  && (orig_st_shndx != elfcpp::SHN_UNDEF || !is_ordinary))
1332         {
1333 	  // We may have copied symbol already above.
1334 	  if (psym != &sym2)
1335 	    {
1336 	      memcpy(symbuf, p, sym_size);
1337 	      psym = &sym2;
1338 	    }
1339 
1340 	  elfcpp::STV visibility = sym2.get_st_visibility();
1341 	  if (visibility == elfcpp::STV_DEFAULT
1342 	      || visibility == elfcpp::STV_PROTECTED)
1343 	    {
1344 	      elfcpp::Sym_write<size, big_endian> sw(symbuf);
1345 	      unsigned char nonvis = sym2.get_st_nonvis();
1346 	      sw.put_st_other(elfcpp::STV_HIDDEN, nonvis);
1347 	    }
1348         }
1349 
1350       Stringpool::Key name_key;
1351       name = this->namepool_.add_with_length(name, namelen, true,
1352 					     &name_key);
1353 
1354       Sized_symbol<size>* res;
1355       res = this->add_from_object(relobj, name, name_key, ver, ver_key,
1356 				  is_default_version, *psym, st_shndx,
1357 				  is_ordinary, orig_st_shndx);
1358 
1359       if (res == NULL)
1360 	continue;
1361 
1362       if (is_forced_local)
1363 	this->force_local(res);
1364 
1365       // Do not treat this symbol as garbage if this symbol will be
1366       // exported to the dynamic symbol table.  This is true when
1367       // building a shared library or using --export-dynamic and
1368       // the symbol is externally visible.
1369       if (parameters->options().gc_sections()
1370 	  && res->is_externally_visible()
1371 	  && !res->is_from_dynobj()
1372           && (parameters->options().shared()
1373 	      || parameters->options().export_dynamic()
1374 	      || parameters->options().in_dynamic_list(res->name())))
1375         this->gc_mark_symbol(res);
1376 
1377       if (is_defined_in_discarded_section)
1378 	res->set_is_defined_in_discarded_section();
1379 
1380       (*sympointers)[i] = res;
1381     }
1382 }
1383 
1384 // Add a symbol from a plugin-claimed file.
1385 
1386 template<int size, bool big_endian>
1387 Symbol*
add_from_pluginobj(Sized_pluginobj<size,big_endian> * obj,const char * name,const char * ver,elfcpp::Sym<size,big_endian> * sym)1388 Symbol_table::add_from_pluginobj(
1389     Sized_pluginobj<size, big_endian>* obj,
1390     const char* name,
1391     const char* ver,
1392     elfcpp::Sym<size, big_endian>* sym)
1393 {
1394   unsigned int st_shndx = sym->get_st_shndx();
1395   bool is_ordinary = st_shndx < elfcpp::SHN_LORESERVE;
1396 
1397   Stringpool::Key ver_key = 0;
1398   bool is_default_version = false;
1399   bool is_forced_local = false;
1400 
1401   if (ver != NULL)
1402     {
1403       ver = this->namepool_.add(ver, true, &ver_key);
1404     }
1405   // We don't want to assign a version to an undefined symbol,
1406   // even if it is listed in the version script.  FIXME: What
1407   // about a common symbol?
1408   else
1409     {
1410       if (!this->version_script_.empty()
1411           && st_shndx != elfcpp::SHN_UNDEF)
1412         {
1413           // The symbol name did not have a version, but the
1414           // version script may assign a version anyway.
1415           std::string version;
1416 	  bool is_global;
1417           if (this->version_script_.get_symbol_version(name, &version,
1418 						       &is_global))
1419             {
1420 	      if (!is_global)
1421 		is_forced_local = true;
1422 	      else if (!version.empty())
1423                 {
1424                   ver = this->namepool_.add_with_length(version.c_str(),
1425                                                         version.length(),
1426                                                         true,
1427                                                         &ver_key);
1428                   is_default_version = true;
1429                 }
1430             }
1431         }
1432     }
1433 
1434   Stringpool::Key name_key;
1435   name = this->namepool_.add(name, true, &name_key);
1436 
1437   Sized_symbol<size>* res;
1438   res = this->add_from_object(obj, name, name_key, ver, ver_key,
1439 		              is_default_version, *sym, st_shndx,
1440 			      is_ordinary, st_shndx);
1441 
1442   if (res == NULL)
1443     return NULL;
1444 
1445   if (is_forced_local)
1446     this->force_local(res);
1447 
1448   return res;
1449 }
1450 
1451 // Add all the symbols in a dynamic object to the hash table.
1452 
1453 template<int size, bool big_endian>
1454 void
add_from_dynobj(Sized_dynobj<size,big_endian> * dynobj,const unsigned char * syms,size_t count,const char * sym_names,size_t sym_name_size,const unsigned char * versym,size_t versym_size,const std::vector<const char * > * version_map,typename Sized_relobj_file<size,big_endian>::Symbols * sympointers,size_t * defined)1455 Symbol_table::add_from_dynobj(
1456     Sized_dynobj<size, big_endian>* dynobj,
1457     const unsigned char* syms,
1458     size_t count,
1459     const char* sym_names,
1460     size_t sym_name_size,
1461     const unsigned char* versym,
1462     size_t versym_size,
1463     const std::vector<const char*>* version_map,
1464     typename Sized_relobj_file<size, big_endian>::Symbols* sympointers,
1465     size_t* defined)
1466 {
1467   *defined = 0;
1468 
1469   gold_assert(size == parameters->target().get_size());
1470 
1471   if (dynobj->just_symbols())
1472     {
1473       gold_error(_("--just-symbols does not make sense with a shared object"));
1474       return;
1475     }
1476 
1477   // FIXME: For incremental links, we don't store version information,
1478   // so we need to ignore version symbols for now.
1479   if (parameters->incremental_update())
1480     versym = NULL;
1481 
1482   if (versym != NULL && versym_size / 2 < count)
1483     {
1484       dynobj->error(_("too few symbol versions"));
1485       return;
1486     }
1487 
1488   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1489 
1490   // We keep a list of all STT_OBJECT symbols, so that we can resolve
1491   // weak aliases.  This is necessary because if the dynamic object
1492   // provides the same variable under two names, one of which is a
1493   // weak definition, and the regular object refers to the weak
1494   // definition, we have to put both the weak definition and the
1495   // strong definition into the dynamic symbol table.  Given a weak
1496   // definition, the only way that we can find the corresponding
1497   // strong definition, if any, is to search the symbol table.
1498   std::vector<Sized_symbol<size>*> object_symbols;
1499 
1500   const unsigned char* p = syms;
1501   const unsigned char* vs = versym;
1502   for (size_t i = 0; i < count; ++i, p += sym_size, vs += 2)
1503     {
1504       elfcpp::Sym<size, big_endian> sym(p);
1505 
1506       if (sympointers != NULL)
1507 	(*sympointers)[i] = NULL;
1508 
1509       // Ignore symbols with local binding or that have
1510       // internal or hidden visibility.
1511       if (sym.get_st_bind() == elfcpp::STB_LOCAL
1512           || sym.get_st_visibility() == elfcpp::STV_INTERNAL
1513           || sym.get_st_visibility() == elfcpp::STV_HIDDEN)
1514 	continue;
1515 
1516       // A protected symbol in a shared library must be treated as a
1517       // normal symbol when viewed from outside the shared library.
1518       // Implement this by overriding the visibility here.
1519       // Likewise, an IFUNC symbol in a shared library must be treated
1520       // as a normal FUNC symbol.
1521       elfcpp::Sym<size, big_endian>* psym = &sym;
1522       unsigned char symbuf[sym_size];
1523       elfcpp::Sym<size, big_endian> sym2(symbuf);
1524       if (sym.get_st_visibility() == elfcpp::STV_PROTECTED
1525 	  || sym.get_st_type() == elfcpp::STT_GNU_IFUNC)
1526 	{
1527 	  memcpy(symbuf, p, sym_size);
1528 	  elfcpp::Sym_write<size, big_endian> sw(symbuf);
1529 	  if (sym.get_st_visibility() == elfcpp::STV_PROTECTED)
1530 	    sw.put_st_other(elfcpp::STV_DEFAULT, sym.get_st_nonvis());
1531 	  if (sym.get_st_type() == elfcpp::STT_GNU_IFUNC)
1532 	    sw.put_st_info(sym.get_st_bind(), elfcpp::STT_FUNC);
1533 	  psym = &sym2;
1534 	}
1535 
1536       unsigned int st_name = psym->get_st_name();
1537       if (st_name >= sym_name_size)
1538 	{
1539 	  dynobj->error(_("bad symbol name offset %u at %zu"),
1540 			st_name, i);
1541 	  continue;
1542 	}
1543 
1544       const char* name = sym_names + st_name;
1545 
1546       bool is_ordinary;
1547       unsigned int st_shndx = dynobj->adjust_sym_shndx(i, psym->get_st_shndx(),
1548 						       &is_ordinary);
1549 
1550       if (st_shndx != elfcpp::SHN_UNDEF)
1551 	++*defined;
1552 
1553       Sized_symbol<size>* res;
1554 
1555       if (versym == NULL)
1556 	{
1557 	  Stringpool::Key name_key;
1558 	  name = this->namepool_.add(name, true, &name_key);
1559 	  res = this->add_from_object(dynobj, name, name_key, NULL, 0,
1560 				      false, *psym, st_shndx, is_ordinary,
1561 				      st_shndx);
1562 	}
1563       else
1564 	{
1565 	  // Read the version information.
1566 
1567 	  unsigned int v = elfcpp::Swap<16, big_endian>::readval(vs);
1568 
1569 	  bool hidden = (v & elfcpp::VERSYM_HIDDEN) != 0;
1570 	  v &= elfcpp::VERSYM_VERSION;
1571 
1572 	  // The Sun documentation says that V can be VER_NDX_LOCAL,
1573 	  // or VER_NDX_GLOBAL, or a version index.  The meaning of
1574 	  // VER_NDX_LOCAL is defined as "Symbol has local scope."
1575 	  // The old GNU linker will happily generate VER_NDX_LOCAL
1576 	  // for an undefined symbol.  I don't know what the Sun
1577 	  // linker will generate.
1578 
1579 	  if (v == static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL)
1580 	      && st_shndx != elfcpp::SHN_UNDEF)
1581 	    {
1582 	      // This symbol should not be visible outside the object.
1583 	      continue;
1584 	    }
1585 
1586 	  // At this point we are definitely going to add this symbol.
1587 	  Stringpool::Key name_key;
1588 	  name = this->namepool_.add(name, true, &name_key);
1589 
1590 	  if (v == static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL)
1591 	      || v == static_cast<unsigned int>(elfcpp::VER_NDX_GLOBAL))
1592 	    {
1593 	      // This symbol does not have a version.
1594 	      res = this->add_from_object(dynobj, name, name_key, NULL, 0,
1595 					  false, *psym, st_shndx, is_ordinary,
1596 					  st_shndx);
1597 	    }
1598 	  else
1599 	    {
1600 	      if (v >= version_map->size())
1601 		{
1602 		  dynobj->error(_("versym for symbol %zu out of range: %u"),
1603 				i, v);
1604 		  continue;
1605 		}
1606 
1607 	      const char* version = (*version_map)[v];
1608 	      if (version == NULL)
1609 		{
1610 		  dynobj->error(_("versym for symbol %zu has no name: %u"),
1611 				i, v);
1612 		  continue;
1613 		}
1614 
1615 	      Stringpool::Key version_key;
1616 	      version = this->namepool_.add(version, true, &version_key);
1617 
1618 	      // If this is an absolute symbol, and the version name
1619 	      // and symbol name are the same, then this is the
1620 	      // version definition symbol.  These symbols exist to
1621 	      // support using -u to pull in particular versions.  We
1622 	      // do not want to record a version for them.
1623 	      if (st_shndx == elfcpp::SHN_ABS
1624 		  && !is_ordinary
1625 		  && name_key == version_key)
1626 		res = this->add_from_object(dynobj, name, name_key, NULL, 0,
1627 					    false, *psym, st_shndx, is_ordinary,
1628 					    st_shndx);
1629 	      else
1630 		{
1631 		  const bool is_default_version =
1632 		    !hidden && st_shndx != elfcpp::SHN_UNDEF;
1633 		  res = this->add_from_object(dynobj, name, name_key, version,
1634 					      version_key, is_default_version,
1635 					      *psym, st_shndx,
1636 					      is_ordinary, st_shndx);
1637 		}
1638 	    }
1639 	}
1640 
1641       if (res == NULL)
1642 	continue;
1643 
1644       // Note that it is possible that RES was overridden by an
1645       // earlier object, in which case it can't be aliased here.
1646       if (st_shndx != elfcpp::SHN_UNDEF
1647 	  && is_ordinary
1648 	  && psym->get_st_type() == elfcpp::STT_OBJECT
1649 	  && res->source() == Symbol::FROM_OBJECT
1650 	  && res->object() == dynobj)
1651 	object_symbols.push_back(res);
1652 
1653       // If the symbol has protected visibility in the dynobj,
1654       // mark it as such if it was not overridden.
1655       if (res->source() == Symbol::FROM_OBJECT
1656           && res->object() == dynobj
1657           && sym.get_st_visibility() == elfcpp::STV_PROTECTED)
1658         res->set_is_protected();
1659 
1660       if (sympointers != NULL)
1661 	(*sympointers)[i] = res;
1662     }
1663 
1664   this->record_weak_aliases(&object_symbols);
1665 }
1666 
1667 // Add a symbol from a incremental object file.
1668 
1669 template<int size, bool big_endian>
1670 Sized_symbol<size>*
add_from_incrobj(Object * obj,const char * name,const char * ver,elfcpp::Sym<size,big_endian> * sym)1671 Symbol_table::add_from_incrobj(
1672     Object* obj,
1673     const char* name,
1674     const char* ver,
1675     elfcpp::Sym<size, big_endian>* sym)
1676 {
1677   unsigned int st_shndx = sym->get_st_shndx();
1678   bool is_ordinary = st_shndx < elfcpp::SHN_LORESERVE;
1679 
1680   Stringpool::Key ver_key = 0;
1681   bool is_default_version = false;
1682 
1683   Stringpool::Key name_key;
1684   name = this->namepool_.add(name, true, &name_key);
1685 
1686   Sized_symbol<size>* res;
1687   res = this->add_from_object(obj, name, name_key, ver, ver_key,
1688 		              is_default_version, *sym, st_shndx,
1689 			      is_ordinary, st_shndx);
1690 
1691   return res;
1692 }
1693 
1694 // This is used to sort weak aliases.  We sort them first by section
1695 // index, then by offset, then by weak ahead of strong.
1696 
1697 template<int size>
1698 class Weak_alias_sorter
1699 {
1700  public:
1701   bool operator()(const Sized_symbol<size>*, const Sized_symbol<size>*) const;
1702 };
1703 
1704 template<int size>
1705 bool
operator ()(const Sized_symbol<size> * s1,const Sized_symbol<size> * s2) const1706 Weak_alias_sorter<size>::operator()(const Sized_symbol<size>* s1,
1707 				    const Sized_symbol<size>* s2) const
1708 {
1709   bool is_ordinary;
1710   unsigned int s1_shndx = s1->shndx(&is_ordinary);
1711   gold_assert(is_ordinary);
1712   unsigned int s2_shndx = s2->shndx(&is_ordinary);
1713   gold_assert(is_ordinary);
1714   if (s1_shndx != s2_shndx)
1715     return s1_shndx < s2_shndx;
1716 
1717   if (s1->value() != s2->value())
1718     return s1->value() < s2->value();
1719   if (s1->binding() != s2->binding())
1720     {
1721       if (s1->binding() == elfcpp::STB_WEAK)
1722 	return true;
1723       if (s2->binding() == elfcpp::STB_WEAK)
1724 	return false;
1725     }
1726   return std::string(s1->name()) < std::string(s2->name());
1727 }
1728 
1729 // SYMBOLS is a list of object symbols from a dynamic object.  Look
1730 // for any weak aliases, and record them so that if we add the weak
1731 // alias to the dynamic symbol table, we also add the corresponding
1732 // strong symbol.
1733 
1734 template<int size>
1735 void
record_weak_aliases(std::vector<Sized_symbol<size> * > * symbols)1736 Symbol_table::record_weak_aliases(std::vector<Sized_symbol<size>*>* symbols)
1737 {
1738   // Sort the vector by section index, then by offset, then by weak
1739   // ahead of strong.
1740   std::sort(symbols->begin(), symbols->end(), Weak_alias_sorter<size>());
1741 
1742   // Walk through the vector.  For each weak definition, record
1743   // aliases.
1744   for (typename std::vector<Sized_symbol<size>*>::const_iterator p =
1745 	 symbols->begin();
1746        p != symbols->end();
1747        ++p)
1748     {
1749       if ((*p)->binding() != elfcpp::STB_WEAK)
1750 	continue;
1751 
1752       // Build a circular list of weak aliases.  Each symbol points to
1753       // the next one in the circular list.
1754 
1755       Sized_symbol<size>* from_sym = *p;
1756       typename std::vector<Sized_symbol<size>*>::const_iterator q;
1757       for (q = p + 1; q != symbols->end(); ++q)
1758 	{
1759 	  bool dummy;
1760 	  if ((*q)->shndx(&dummy) != from_sym->shndx(&dummy)
1761 	      || (*q)->value() != from_sym->value())
1762 	    break;
1763 
1764 	  this->weak_aliases_[from_sym] = *q;
1765 	  from_sym->set_has_alias();
1766 	  from_sym = *q;
1767 	}
1768 
1769       if (from_sym != *p)
1770 	{
1771 	  this->weak_aliases_[from_sym] = *p;
1772 	  from_sym->set_has_alias();
1773 	}
1774 
1775       p = q - 1;
1776     }
1777 }
1778 
1779 // Create and return a specially defined symbol.  If ONLY_IF_REF is
1780 // true, then only create the symbol if there is a reference to it.
1781 // If this does not return NULL, it sets *POLDSYM to the existing
1782 // symbol if there is one.  This sets *RESOLVE_OLDSYM if we should
1783 // resolve the newly created symbol to the old one.  This
1784 // canonicalizes *PNAME and *PVERSION.
1785 
1786 template<int size, bool big_endian>
1787 Sized_symbol<size>*
define_special_symbol(const char ** pname,const char ** pversion,bool only_if_ref,elfcpp::STV visibility,Sized_symbol<size> ** poldsym,bool * resolve_oldsym,bool is_forced_local)1788 Symbol_table::define_special_symbol(const char** pname, const char** pversion,
1789 				    bool only_if_ref,
1790 				    elfcpp::STV visibility,
1791                                     Sized_symbol<size>** poldsym,
1792 				    bool* resolve_oldsym, bool is_forced_local)
1793 {
1794   *resolve_oldsym = false;
1795   *poldsym = NULL;
1796 
1797   // If the caller didn't give us a version, see if we get one from
1798   // the version script.
1799   std::string v;
1800   bool is_default_version = false;
1801   if (!is_forced_local && *pversion == NULL)
1802     {
1803       bool is_global;
1804       if (this->version_script_.get_symbol_version(*pname, &v, &is_global))
1805 	{
1806 	  if (is_global && !v.empty())
1807 	    {
1808 	      *pversion = v.c_str();
1809 	      // If we get the version from a version script, then we
1810 	      // are also the default version.
1811 	      is_default_version = true;
1812 	    }
1813 	}
1814     }
1815 
1816   Symbol* oldsym;
1817   Sized_symbol<size>* sym;
1818 
1819   bool add_to_table = false;
1820   typename Symbol_table_type::iterator add_loc = this->table_.end();
1821   bool add_def_to_table = false;
1822   typename Symbol_table_type::iterator add_def_loc = this->table_.end();
1823 
1824   if (only_if_ref)
1825     {
1826       oldsym = this->lookup(*pname, *pversion);
1827       if (oldsym == NULL && is_default_version)
1828 	oldsym = this->lookup(*pname, NULL);
1829       if (oldsym == NULL)
1830 	return NULL;
1831       if (!oldsym->is_undefined())
1832 	{
1833 	  // Skip if the old definition is from a regular object.
1834 	  if (!oldsym->is_from_dynobj())
1835 	    return NULL;
1836 
1837 	  // If the symbol has hidden or internal visibility, ignore
1838 	  // definition and reference from a dynamic object.
1839 	  if ((visibility == elfcpp::STV_HIDDEN
1840 	       || visibility == elfcpp::STV_INTERNAL)
1841 	      && !oldsym->in_reg())
1842 	    return NULL;
1843 	}
1844 
1845       *pname = oldsym->name();
1846       if (is_default_version)
1847 	*pversion = this->namepool_.add(*pversion, true, NULL);
1848       else
1849 	*pversion = oldsym->version();
1850     }
1851   else
1852     {
1853       // Canonicalize NAME and VERSION.
1854       Stringpool::Key name_key;
1855       *pname = this->namepool_.add(*pname, true, &name_key);
1856 
1857       Stringpool::Key version_key = 0;
1858       if (*pversion != NULL)
1859 	*pversion = this->namepool_.add(*pversion, true, &version_key);
1860 
1861       Symbol* const snull = NULL;
1862       std::pair<typename Symbol_table_type::iterator, bool> ins =
1863 	this->table_.insert(std::make_pair(std::make_pair(name_key,
1864 							  version_key),
1865 					   snull));
1866 
1867       std::pair<typename Symbol_table_type::iterator, bool> insdefault =
1868 	std::make_pair(this->table_.end(), false);
1869       if (is_default_version)
1870 	{
1871 	  const Stringpool::Key vnull = 0;
1872 	  insdefault =
1873 	    this->table_.insert(std::make_pair(std::make_pair(name_key,
1874 							      vnull),
1875 					       snull));
1876 	}
1877 
1878       if (!ins.second)
1879 	{
1880 	  // We already have a symbol table entry for NAME/VERSION.
1881 	  oldsym = ins.first->second;
1882 	  gold_assert(oldsym != NULL);
1883 
1884 	  if (is_default_version)
1885 	    {
1886 	      Sized_symbol<size>* soldsym =
1887 		this->get_sized_symbol<size>(oldsym);
1888 	      this->define_default_version<size, big_endian>(soldsym,
1889 							     insdefault.second,
1890 							     insdefault.first);
1891 	    }
1892 	}
1893       else
1894 	{
1895 	  // We haven't seen this symbol before.
1896 	  gold_assert(ins.first->second == NULL);
1897 
1898 	  add_to_table = true;
1899 	  add_loc = ins.first;
1900 
1901 	  if (is_default_version
1902 	      && !insdefault.second
1903 	      && insdefault.first->second->version() == NULL)
1904 	    {
1905 	      // We are adding NAME/VERSION, and it is the default
1906 	      // version.  We already have an entry for NAME/NULL
1907 	      // that does not already have a version.
1908 	      oldsym = insdefault.first->second;
1909 	      *resolve_oldsym = true;
1910 	    }
1911 	  else
1912 	    {
1913 	      oldsym = NULL;
1914 
1915 	      if (is_default_version)
1916 		{
1917 		  add_def_to_table = true;
1918 		  add_def_loc = insdefault.first;
1919 		}
1920 	    }
1921 	}
1922     }
1923 
1924   const Target& target = parameters->target();
1925   if (!target.has_make_symbol())
1926     sym = new Sized_symbol<size>();
1927   else
1928     {
1929       Sized_target<size, big_endian>* sized_target =
1930 	parameters->sized_target<size, big_endian>();
1931       sym = sized_target->make_symbol(*pname, elfcpp::STT_NOTYPE,
1932 				      NULL, elfcpp::SHN_UNDEF, 0);
1933       if (sym == NULL)
1934         return NULL;
1935     }
1936 
1937   if (add_to_table)
1938     add_loc->second = sym;
1939   else
1940     gold_assert(oldsym != NULL);
1941 
1942   if (add_def_to_table)
1943     add_def_loc->second = sym;
1944 
1945   *poldsym = this->get_sized_symbol<size>(oldsym);
1946 
1947   return sym;
1948 }
1949 
1950 // Define a symbol based on an Output_data.
1951 
1952 Symbol*
define_in_output_data(const char * name,const char * version,Defined defined,Output_data * od,uint64_t value,uint64_t symsize,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis,bool offset_is_from_end,bool only_if_ref)1953 Symbol_table::define_in_output_data(const char* name,
1954 				    const char* version,
1955 				    Defined defined,
1956 				    Output_data* od,
1957 				    uint64_t value,
1958 				    uint64_t symsize,
1959 				    elfcpp::STT type,
1960 				    elfcpp::STB binding,
1961 				    elfcpp::STV visibility,
1962 				    unsigned char nonvis,
1963 				    bool offset_is_from_end,
1964 				    bool only_if_ref)
1965 {
1966   if (parameters->target().get_size() == 32)
1967     {
1968 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1969       return this->do_define_in_output_data<32>(name, version, defined, od,
1970                                                 value, symsize, type, binding,
1971                                                 visibility, nonvis,
1972                                                 offset_is_from_end,
1973                                                 only_if_ref);
1974 #else
1975       gold_unreachable();
1976 #endif
1977     }
1978   else if (parameters->target().get_size() == 64)
1979     {
1980 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1981       return this->do_define_in_output_data<64>(name, version, defined, od,
1982                                                 value, symsize, type, binding,
1983                                                 visibility, nonvis,
1984                                                 offset_is_from_end,
1985                                                 only_if_ref);
1986 #else
1987       gold_unreachable();
1988 #endif
1989     }
1990   else
1991     gold_unreachable();
1992 }
1993 
1994 // Define a symbol in an Output_data, sized version.
1995 
1996 template<int size>
1997 Sized_symbol<size>*
do_define_in_output_data(const char * name,const char * version,Defined defined,Output_data * od,typename elfcpp::Elf_types<size>::Elf_Addr value,typename elfcpp::Elf_types<size>::Elf_WXword symsize,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis,bool offset_is_from_end,bool only_if_ref)1998 Symbol_table::do_define_in_output_data(
1999     const char* name,
2000     const char* version,
2001     Defined defined,
2002     Output_data* od,
2003     typename elfcpp::Elf_types<size>::Elf_Addr value,
2004     typename elfcpp::Elf_types<size>::Elf_WXword symsize,
2005     elfcpp::STT type,
2006     elfcpp::STB binding,
2007     elfcpp::STV visibility,
2008     unsigned char nonvis,
2009     bool offset_is_from_end,
2010     bool only_if_ref)
2011 {
2012   Sized_symbol<size>* sym;
2013   Sized_symbol<size>* oldsym;
2014   bool resolve_oldsym;
2015   const bool is_forced_local = binding == elfcpp::STB_LOCAL;
2016 
2017   if (parameters->target().is_big_endian())
2018     {
2019 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2020       sym = this->define_special_symbol<size, true>(&name, &version,
2021 						    only_if_ref,
2022 						    visibility,
2023 						    &oldsym,
2024 						    &resolve_oldsym,
2025 						    is_forced_local);
2026 #else
2027       gold_unreachable();
2028 #endif
2029     }
2030   else
2031     {
2032 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2033       sym = this->define_special_symbol<size, false>(&name, &version,
2034 						     only_if_ref,
2035 						     visibility,
2036 						     &oldsym,
2037 						     &resolve_oldsym,
2038 						     is_forced_local);
2039 #else
2040       gold_unreachable();
2041 #endif
2042     }
2043 
2044   if (sym == NULL)
2045     return NULL;
2046 
2047   sym->init_output_data(name, version, od, value, symsize, type, binding,
2048 			visibility, nonvis, offset_is_from_end,
2049 			defined == PREDEFINED);
2050 
2051   if (oldsym == NULL)
2052     {
2053       if (is_forced_local || this->version_script_.symbol_is_local(name))
2054 	this->force_local(sym);
2055       else if (version != NULL)
2056 	sym->set_is_default();
2057       return sym;
2058     }
2059 
2060   if (Symbol_table::should_override_with_special(oldsym, type, defined))
2061     this->override_with_special(oldsym, sym);
2062 
2063   if (resolve_oldsym)
2064     return sym;
2065   else
2066     {
2067       if (defined == PREDEFINED
2068 	  && (is_forced_local || this->version_script_.symbol_is_local(name)))
2069 	this->force_local(oldsym);
2070       delete sym;
2071       return oldsym;
2072     }
2073 }
2074 
2075 // Define a symbol based on an Output_segment.
2076 
2077 Symbol*
define_in_output_segment(const char * name,const char * version,Defined defined,Output_segment * os,uint64_t value,uint64_t symsize,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis,Symbol::Segment_offset_base offset_base,bool only_if_ref)2078 Symbol_table::define_in_output_segment(const char* name,
2079 				       const char* version,
2080 				       Defined defined,
2081 				       Output_segment* os,
2082 				       uint64_t value,
2083 				       uint64_t symsize,
2084 				       elfcpp::STT type,
2085 				       elfcpp::STB binding,
2086 				       elfcpp::STV visibility,
2087 				       unsigned char nonvis,
2088 				       Symbol::Segment_offset_base offset_base,
2089 				       bool only_if_ref)
2090 {
2091   if (parameters->target().get_size() == 32)
2092     {
2093 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2094       return this->do_define_in_output_segment<32>(name, version, defined, os,
2095                                                    value, symsize, type,
2096                                                    binding, visibility, nonvis,
2097                                                    offset_base, only_if_ref);
2098 #else
2099       gold_unreachable();
2100 #endif
2101     }
2102   else if (parameters->target().get_size() == 64)
2103     {
2104 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2105       return this->do_define_in_output_segment<64>(name, version, defined, os,
2106                                                    value, symsize, type,
2107                                                    binding, visibility, nonvis,
2108                                                    offset_base, only_if_ref);
2109 #else
2110       gold_unreachable();
2111 #endif
2112     }
2113   else
2114     gold_unreachable();
2115 }
2116 
2117 // Define a symbol in an Output_segment, sized version.
2118 
2119 template<int size>
2120 Sized_symbol<size>*
do_define_in_output_segment(const char * name,const char * version,Defined defined,Output_segment * os,typename elfcpp::Elf_types<size>::Elf_Addr value,typename elfcpp::Elf_types<size>::Elf_WXword symsize,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis,Symbol::Segment_offset_base offset_base,bool only_if_ref)2121 Symbol_table::do_define_in_output_segment(
2122     const char* name,
2123     const char* version,
2124     Defined defined,
2125     Output_segment* os,
2126     typename elfcpp::Elf_types<size>::Elf_Addr value,
2127     typename elfcpp::Elf_types<size>::Elf_WXword symsize,
2128     elfcpp::STT type,
2129     elfcpp::STB binding,
2130     elfcpp::STV visibility,
2131     unsigned char nonvis,
2132     Symbol::Segment_offset_base offset_base,
2133     bool only_if_ref)
2134 {
2135   Sized_symbol<size>* sym;
2136   Sized_symbol<size>* oldsym;
2137   bool resolve_oldsym;
2138   const bool is_forced_local = binding == elfcpp::STB_LOCAL;
2139 
2140   if (parameters->target().is_big_endian())
2141     {
2142 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2143       sym = this->define_special_symbol<size, true>(&name, &version,
2144 						    only_if_ref,
2145 						    visibility,
2146 						    &oldsym,
2147 						    &resolve_oldsym,
2148 						    is_forced_local);
2149 #else
2150       gold_unreachable();
2151 #endif
2152     }
2153   else
2154     {
2155 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2156       sym = this->define_special_symbol<size, false>(&name, &version,
2157 						     only_if_ref,
2158 						     visibility,
2159 						     &oldsym,
2160 						     &resolve_oldsym,
2161 						     is_forced_local);
2162 #else
2163       gold_unreachable();
2164 #endif
2165     }
2166 
2167   if (sym == NULL)
2168     return NULL;
2169 
2170   sym->init_output_segment(name, version, os, value, symsize, type, binding,
2171 			   visibility, nonvis, offset_base,
2172 			   defined == PREDEFINED);
2173 
2174   if (oldsym == NULL)
2175     {
2176       if (is_forced_local || this->version_script_.symbol_is_local(name))
2177 	this->force_local(sym);
2178       else if (version != NULL)
2179 	sym->set_is_default();
2180       return sym;
2181     }
2182 
2183   if (Symbol_table::should_override_with_special(oldsym, type, defined))
2184     this->override_with_special(oldsym, sym);
2185 
2186   if (resolve_oldsym)
2187     return sym;
2188   else
2189     {
2190       if (is_forced_local || this->version_script_.symbol_is_local(name))
2191 	this->force_local(oldsym);
2192       delete sym;
2193       return oldsym;
2194     }
2195 }
2196 
2197 // Define a special symbol with a constant value.  It is a multiple
2198 // definition error if this symbol is already defined.
2199 
2200 Symbol*
define_as_constant(const char * name,const char * version,Defined defined,uint64_t value,uint64_t symsize,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis,bool only_if_ref,bool force_override)2201 Symbol_table::define_as_constant(const char* name,
2202 				 const char* version,
2203 				 Defined defined,
2204 				 uint64_t value,
2205 				 uint64_t symsize,
2206 				 elfcpp::STT type,
2207 				 elfcpp::STB binding,
2208 				 elfcpp::STV visibility,
2209 				 unsigned char nonvis,
2210 				 bool only_if_ref,
2211                                  bool force_override)
2212 {
2213   if (parameters->target().get_size() == 32)
2214     {
2215 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2216       return this->do_define_as_constant<32>(name, version, defined, value,
2217                                              symsize, type, binding,
2218                                              visibility, nonvis, only_if_ref,
2219                                              force_override);
2220 #else
2221       gold_unreachable();
2222 #endif
2223     }
2224   else if (parameters->target().get_size() == 64)
2225     {
2226 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2227       return this->do_define_as_constant<64>(name, version, defined, value,
2228                                              symsize, type, binding,
2229                                              visibility, nonvis, only_if_ref,
2230                                              force_override);
2231 #else
2232       gold_unreachable();
2233 #endif
2234     }
2235   else
2236     gold_unreachable();
2237 }
2238 
2239 // Define a symbol as a constant, sized version.
2240 
2241 template<int size>
2242 Sized_symbol<size>*
do_define_as_constant(const char * name,const char * version,Defined defined,typename elfcpp::Elf_types<size>::Elf_Addr value,typename elfcpp::Elf_types<size>::Elf_WXword symsize,elfcpp::STT type,elfcpp::STB binding,elfcpp::STV visibility,unsigned char nonvis,bool only_if_ref,bool force_override)2243 Symbol_table::do_define_as_constant(
2244     const char* name,
2245     const char* version,
2246     Defined defined,
2247     typename elfcpp::Elf_types<size>::Elf_Addr value,
2248     typename elfcpp::Elf_types<size>::Elf_WXword symsize,
2249     elfcpp::STT type,
2250     elfcpp::STB binding,
2251     elfcpp::STV visibility,
2252     unsigned char nonvis,
2253     bool only_if_ref,
2254     bool force_override)
2255 {
2256   Sized_symbol<size>* sym;
2257   Sized_symbol<size>* oldsym;
2258   bool resolve_oldsym;
2259   const bool is_forced_local = binding == elfcpp::STB_LOCAL;
2260 
2261   if (parameters->target().is_big_endian())
2262     {
2263 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2264       sym = this->define_special_symbol<size, true>(&name, &version,
2265 						    only_if_ref,
2266 						    visibility,
2267 						    &oldsym,
2268 						    &resolve_oldsym,
2269 						    is_forced_local);
2270 #else
2271       gold_unreachable();
2272 #endif
2273     }
2274   else
2275     {
2276 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2277       sym = this->define_special_symbol<size, false>(&name, &version,
2278 						     only_if_ref,
2279 						     visibility,
2280 						     &oldsym,
2281 						     &resolve_oldsym,
2282 						     is_forced_local);
2283 #else
2284       gold_unreachable();
2285 #endif
2286     }
2287 
2288   if (sym == NULL)
2289     return NULL;
2290 
2291   sym->init_constant(name, version, value, symsize, type, binding, visibility,
2292 		     nonvis, defined == PREDEFINED);
2293 
2294   if (oldsym == NULL)
2295     {
2296       // Version symbols are absolute symbols with name == version.
2297       // We don't want to force them to be local.
2298       if ((version == NULL
2299 	   || name != version
2300 	   || value != 0)
2301 	  && (is_forced_local || this->version_script_.symbol_is_local(name)))
2302 	this->force_local(sym);
2303       else if (version != NULL
2304 	       && (name != version || value != 0))
2305 	sym->set_is_default();
2306       return sym;
2307     }
2308 
2309   if (force_override
2310       || Symbol_table::should_override_with_special(oldsym, type, defined))
2311     this->override_with_special(oldsym, sym);
2312 
2313   if (resolve_oldsym)
2314     return sym;
2315   else
2316     {
2317       if (is_forced_local || this->version_script_.symbol_is_local(name))
2318 	this->force_local(oldsym);
2319       delete sym;
2320       return oldsym;
2321     }
2322 }
2323 
2324 // Define a set of symbols in output sections.
2325 
2326 void
define_symbols(const Layout * layout,int count,const Define_symbol_in_section * p,bool only_if_ref)2327 Symbol_table::define_symbols(const Layout* layout, int count,
2328 			     const Define_symbol_in_section* p,
2329 			     bool only_if_ref)
2330 {
2331   for (int i = 0; i < count; ++i, ++p)
2332     {
2333       Output_section* os = layout->find_output_section(p->output_section);
2334       if (os != NULL)
2335 	this->define_in_output_data(p->name, NULL, PREDEFINED, os, p->value,
2336 				    p->size, p->type, p->binding,
2337 				    p->visibility, p->nonvis,
2338 				    p->offset_is_from_end,
2339 				    only_if_ref || p->only_if_ref);
2340       else
2341 	this->define_as_constant(p->name, NULL, PREDEFINED, 0, p->size,
2342 				 p->type, p->binding, p->visibility, p->nonvis,
2343 				 only_if_ref || p->only_if_ref,
2344                                  false);
2345     }
2346 }
2347 
2348 // Define a set of symbols in output segments.
2349 
2350 void
define_symbols(const Layout * layout,int count,const Define_symbol_in_segment * p,bool only_if_ref)2351 Symbol_table::define_symbols(const Layout* layout, int count,
2352 			     const Define_symbol_in_segment* p,
2353 			     bool only_if_ref)
2354 {
2355   for (int i = 0; i < count; ++i, ++p)
2356     {
2357       Output_segment* os = layout->find_output_segment(p->segment_type,
2358 						       p->segment_flags_set,
2359 						       p->segment_flags_clear);
2360       if (os != NULL)
2361 	this->define_in_output_segment(p->name, NULL, PREDEFINED, os, p->value,
2362 				       p->size, p->type, p->binding,
2363 				       p->visibility, p->nonvis,
2364 				       p->offset_base,
2365 				       only_if_ref || p->only_if_ref);
2366       else
2367 	this->define_as_constant(p->name, NULL, PREDEFINED, 0, p->size,
2368 				 p->type, p->binding, p->visibility, p->nonvis,
2369 				 only_if_ref || p->only_if_ref,
2370                                  false);
2371     }
2372 }
2373 
2374 // Define CSYM using a COPY reloc.  POSD is the Output_data where the
2375 // symbol should be defined--typically a .dyn.bss section.  VALUE is
2376 // the offset within POSD.
2377 
2378 template<int size>
2379 void
define_with_copy_reloc(Sized_symbol<size> * csym,Output_data * posd,typename elfcpp::Elf_types<size>::Elf_Addr value)2380 Symbol_table::define_with_copy_reloc(
2381     Sized_symbol<size>* csym,
2382     Output_data* posd,
2383     typename elfcpp::Elf_types<size>::Elf_Addr value)
2384 {
2385   gold_assert(csym->is_from_dynobj());
2386   gold_assert(!csym->is_copied_from_dynobj());
2387   Object* object = csym->object();
2388   gold_assert(object->is_dynamic());
2389   Dynobj* dynobj = static_cast<Dynobj*>(object);
2390 
2391   // Our copied variable has to override any variable in a shared
2392   // library.
2393   elfcpp::STB binding = csym->binding();
2394   if (binding == elfcpp::STB_WEAK)
2395     binding = elfcpp::STB_GLOBAL;
2396 
2397   this->define_in_output_data(csym->name(), csym->version(), COPY,
2398 			      posd, value, csym->symsize(),
2399 			      csym->type(), binding,
2400 			      csym->visibility(), csym->nonvis(),
2401 			      false, false);
2402 
2403   csym->set_is_copied_from_dynobj();
2404   csym->set_needs_dynsym_entry();
2405 
2406   this->copied_symbol_dynobjs_[csym] = dynobj;
2407 
2408   // We have now defined all aliases, but we have not entered them all
2409   // in the copied_symbol_dynobjs_ map.
2410   if (csym->has_alias())
2411     {
2412       Symbol* sym = csym;
2413       while (true)
2414 	{
2415 	  sym = this->weak_aliases_[sym];
2416 	  if (sym == csym)
2417 	    break;
2418 	  gold_assert(sym->output_data() == posd);
2419 
2420 	  sym->set_is_copied_from_dynobj();
2421 	  this->copied_symbol_dynobjs_[sym] = dynobj;
2422 	}
2423     }
2424 }
2425 
2426 // SYM is defined using a COPY reloc.  Return the dynamic object where
2427 // the original definition was found.
2428 
2429 Dynobj*
get_copy_source(const Symbol * sym) const2430 Symbol_table::get_copy_source(const Symbol* sym) const
2431 {
2432   gold_assert(sym->is_copied_from_dynobj());
2433   Copied_symbol_dynobjs::const_iterator p =
2434     this->copied_symbol_dynobjs_.find(sym);
2435   gold_assert(p != this->copied_symbol_dynobjs_.end());
2436   return p->second;
2437 }
2438 
2439 // Add any undefined symbols named on the command line.
2440 
2441 void
add_undefined_symbols_from_command_line(Layout * layout)2442 Symbol_table::add_undefined_symbols_from_command_line(Layout* layout)
2443 {
2444   if (parameters->options().any_undefined()
2445       || layout->script_options()->any_unreferenced())
2446     {
2447       if (parameters->target().get_size() == 32)
2448 	{
2449 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2450 	  this->do_add_undefined_symbols_from_command_line<32>(layout);
2451 #else
2452 	  gold_unreachable();
2453 #endif
2454 	}
2455       else if (parameters->target().get_size() == 64)
2456 	{
2457 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2458 	  this->do_add_undefined_symbols_from_command_line<64>(layout);
2459 #else
2460 	  gold_unreachable();
2461 #endif
2462 	}
2463       else
2464 	gold_unreachable();
2465     }
2466 }
2467 
2468 template<int size>
2469 void
do_add_undefined_symbols_from_command_line(Layout * layout)2470 Symbol_table::do_add_undefined_symbols_from_command_line(Layout* layout)
2471 {
2472   for (options::String_set::const_iterator p =
2473 	 parameters->options().undefined_begin();
2474        p != parameters->options().undefined_end();
2475        ++p)
2476     this->add_undefined_symbol_from_command_line<size>(p->c_str());
2477 
2478   for (options::String_set::const_iterator p =
2479 	 parameters->options().export_dynamic_symbol_begin();
2480        p != parameters->options().export_dynamic_symbol_end();
2481        ++p)
2482     this->add_undefined_symbol_from_command_line<size>(p->c_str());
2483 
2484   for (Script_options::referenced_const_iterator p =
2485 	 layout->script_options()->referenced_begin();
2486        p != layout->script_options()->referenced_end();
2487        ++p)
2488     this->add_undefined_symbol_from_command_line<size>(p->c_str());
2489 }
2490 
2491 template<int size>
2492 void
add_undefined_symbol_from_command_line(const char * name)2493 Symbol_table::add_undefined_symbol_from_command_line(const char* name)
2494 {
2495   if (this->lookup(name) != NULL)
2496     return;
2497 
2498   const char* version = NULL;
2499 
2500   Sized_symbol<size>* sym;
2501   Sized_symbol<size>* oldsym;
2502   bool resolve_oldsym;
2503   if (parameters->target().is_big_endian())
2504     {
2505 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2506       sym = this->define_special_symbol<size, true>(&name, &version,
2507 						    false,
2508 						    elfcpp::STV_DEFAULT,
2509 						    &oldsym,
2510 						    &resolve_oldsym,
2511 						    false);
2512 #else
2513       gold_unreachable();
2514 #endif
2515     }
2516   else
2517     {
2518 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2519       sym = this->define_special_symbol<size, false>(&name, &version,
2520 						     false,
2521 						     elfcpp::STV_DEFAULT,
2522 						     &oldsym,
2523 						     &resolve_oldsym,
2524 						     false);
2525 #else
2526       gold_unreachable();
2527 #endif
2528     }
2529 
2530   gold_assert(oldsym == NULL);
2531 
2532   sym->init_undefined(name, version, 0, elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
2533 		      elfcpp::STV_DEFAULT, 0);
2534   ++this->saw_undefined_;
2535 }
2536 
2537 // Set the dynamic symbol indexes.  INDEX is the index of the first
2538 // global dynamic symbol.  Pointers to the global symbols are stored
2539 // into the vector SYMS.  The names are added to DYNPOOL.
2540 // This returns an updated dynamic symbol index.
2541 
2542 unsigned int
set_dynsym_indexes(unsigned int index,unsigned int * pforced_local_count,std::vector<Symbol * > * syms,Stringpool * dynpool,Versions * versions)2543 Symbol_table::set_dynsym_indexes(unsigned int index,
2544 				 unsigned int* pforced_local_count,
2545 				 std::vector<Symbol*>* syms,
2546 				 Stringpool* dynpool,
2547 				 Versions* versions)
2548 {
2549   // First process all the symbols which have been forced to be local,
2550   // as they must appear before all global symbols.
2551   unsigned int forced_local_count = 0;
2552   for (Forced_locals::iterator p = this->forced_locals_.begin();
2553        p != this->forced_locals_.end();
2554        ++p)
2555     {
2556       Symbol* sym = *p;
2557       gold_assert(sym->is_forced_local());
2558       if (sym->has_dynsym_index())
2559         continue;
2560       if (!sym->should_add_dynsym_entry(this))
2561 	sym->set_dynsym_index(-1U);
2562       else
2563         {
2564           sym->set_dynsym_index(index);
2565           ++index;
2566           ++forced_local_count;
2567 	  dynpool->add(sym->name(), false, NULL);
2568 	  if (sym->type() == elfcpp::STT_GNU_IFUNC)
2569 	    this->set_has_gnu_output();
2570         }
2571     }
2572   *pforced_local_count = forced_local_count;
2573 
2574   // Allow a target to set dynsym indexes.
2575   if (parameters->target().has_custom_set_dynsym_indexes())
2576     {
2577       std::vector<Symbol*> dyn_symbols;
2578       for (Symbol_table_type::iterator p = this->table_.begin();
2579            p != this->table_.end();
2580            ++p)
2581         {
2582           Symbol* sym = p->second;
2583           if (sym->is_forced_local())
2584 	    continue;
2585           if (!sym->should_add_dynsym_entry(this))
2586             sym->set_dynsym_index(-1U);
2587           else
2588 	    {
2589 	      dyn_symbols.push_back(sym);
2590 	      if (sym->type() == elfcpp::STT_GNU_IFUNC
2591 		  || (sym->binding() == elfcpp::STB_GNU_UNIQUE
2592 		      && parameters->options().gnu_unique()))
2593 		this->set_has_gnu_output();
2594 	    }
2595         }
2596 
2597       return parameters->target().set_dynsym_indexes(&dyn_symbols, index, syms,
2598                                                      dynpool, versions, this);
2599     }
2600 
2601   for (Symbol_table_type::iterator p = this->table_.begin();
2602        p != this->table_.end();
2603        ++p)
2604     {
2605       Symbol* sym = p->second;
2606 
2607       if (sym->is_forced_local())
2608         continue;
2609 
2610       // Note that SYM may already have a dynamic symbol index, since
2611       // some symbols appear more than once in the symbol table, with
2612       // and without a version.
2613 
2614       if (!sym->should_add_dynsym_entry(this))
2615 	sym->set_dynsym_index(-1U);
2616       else if (!sym->has_dynsym_index())
2617 	{
2618 	  sym->set_dynsym_index(index);
2619 	  ++index;
2620 	  syms->push_back(sym);
2621 	  dynpool->add(sym->name(), false, NULL);
2622 	  if (sym->type() == elfcpp::STT_GNU_IFUNC
2623 	      || (sym->binding() == elfcpp::STB_GNU_UNIQUE
2624 		  && parameters->options().gnu_unique()))
2625 	    this->set_has_gnu_output();
2626 
2627 	  // Record any version information, except those from
2628 	  // as-needed libraries not seen to be needed.  Note that the
2629 	  // is_needed state for such libraries can change in this loop.
2630 	  if (sym->version() != NULL)
2631 	    {
2632 	      if (!sym->is_from_dynobj()
2633 		  || !sym->object()->as_needed()
2634 		  || sym->object()->is_needed())
2635 		versions->record_version(this, dynpool, sym);
2636 	      else
2637 		{
2638 		  if (parameters->options().warn_drop_version())
2639 		    gold_warning(_("discarding version information for "
2640 				   "%s@%s, defined in unused shared library %s "
2641 				   "(linked with --as-needed)"),
2642 				 sym->name(), sym->version(),
2643 				 sym->object()->name().c_str());
2644 		  sym->clear_version();
2645 		}
2646 	    }
2647 	}
2648     }
2649 
2650   // Finish up the versions.  In some cases this may add new dynamic
2651   // symbols.
2652   index = versions->finalize(this, index, syms);
2653 
2654   // Process target-specific symbols.
2655   for (std::vector<Symbol*>::iterator p = this->target_symbols_.begin();
2656        p != this->target_symbols_.end();
2657        ++p)
2658     {
2659       (*p)->set_dynsym_index(index);
2660       ++index;
2661       syms->push_back(*p);
2662       dynpool->add((*p)->name(), false, NULL);
2663     }
2664 
2665   return index;
2666 }
2667 
2668 // Set the final values for all the symbols.  The index of the first
2669 // global symbol in the output file is *PLOCAL_SYMCOUNT.  Record the
2670 // file offset OFF.  Add their names to POOL.  Return the new file
2671 // offset.  Update *PLOCAL_SYMCOUNT if necessary.  DYNOFF and
2672 // DYN_GLOBAL_INDEX refer to the start of the symbols that will be
2673 // written from the global symbol table in Symtab::write_globals(),
2674 // which will include forced-local symbols.  DYN_GLOBAL_INDEX is
2675 // not necessarily the same as the sh_info field for the .dynsym
2676 // section, which will point to the first real global symbol.
2677 
2678 off_t
finalize(off_t off,off_t dynoff,size_t dyn_global_index,size_t dyncount,Stringpool * pool,unsigned int * plocal_symcount)2679 Symbol_table::finalize(off_t off, off_t dynoff, size_t dyn_global_index,
2680 		       size_t dyncount, Stringpool* pool,
2681 		       unsigned int* plocal_symcount)
2682 {
2683   off_t ret;
2684 
2685   gold_assert(*plocal_symcount != 0);
2686   this->first_global_index_ = *plocal_symcount;
2687 
2688   this->dynamic_offset_ = dynoff;
2689   this->first_dynamic_global_index_ = dyn_global_index;
2690   this->dynamic_count_ = dyncount;
2691 
2692   if (parameters->target().get_size() == 32)
2693     {
2694 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_32_LITTLE)
2695       ret = this->sized_finalize<32>(off, pool, plocal_symcount);
2696 #else
2697       gold_unreachable();
2698 #endif
2699     }
2700   else if (parameters->target().get_size() == 64)
2701     {
2702 #if defined(HAVE_TARGET_64_BIG) || defined(HAVE_TARGET_64_LITTLE)
2703       ret = this->sized_finalize<64>(off, pool, plocal_symcount);
2704 #else
2705       gold_unreachable();
2706 #endif
2707     }
2708   else
2709     gold_unreachable();
2710 
2711   if (this->has_gnu_output_)
2712     {
2713       Target* target = const_cast<Target*>(&parameters->target());
2714       if (target->osabi() == elfcpp::ELFOSABI_NONE)
2715 	target->set_osabi(elfcpp::ELFOSABI_GNU);
2716     }
2717 
2718   // Now that we have the final symbol table, we can reliably note
2719   // which symbols should get warnings.
2720   this->warnings_.note_warnings(this);
2721 
2722   return ret;
2723 }
2724 
2725 // SYM is going into the symbol table at *PINDEX.  Add the name to
2726 // POOL, update *PINDEX and *POFF.
2727 
2728 template<int size>
2729 void
add_to_final_symtab(Symbol * sym,Stringpool * pool,unsigned int * pindex,off_t * poff)2730 Symbol_table::add_to_final_symtab(Symbol* sym, Stringpool* pool,
2731 				  unsigned int* pindex, off_t* poff)
2732 {
2733   sym->set_symtab_index(*pindex);
2734   if (sym->version() == NULL || !parameters->options().relocatable())
2735     pool->add(sym->name(), false, NULL);
2736   else
2737     pool->add(sym->versioned_name(), true, NULL);
2738   ++*pindex;
2739   *poff += elfcpp::Elf_sizes<size>::sym_size;
2740 }
2741 
2742 // Set the final value for all the symbols.  This is called after
2743 // Layout::finalize, so all the output sections have their final
2744 // address.
2745 
2746 template<int size>
2747 off_t
sized_finalize(off_t off,Stringpool * pool,unsigned int * plocal_symcount)2748 Symbol_table::sized_finalize(off_t off, Stringpool* pool,
2749 			     unsigned int* plocal_symcount)
2750 {
2751   off = align_address(off, size >> 3);
2752   this->offset_ = off;
2753 
2754   unsigned int index = *plocal_symcount;
2755   const unsigned int orig_index = index;
2756 
2757   // First do all the symbols which have been forced to be local, as
2758   // they must appear before all global symbols.
2759   for (Forced_locals::iterator p = this->forced_locals_.begin();
2760        p != this->forced_locals_.end();
2761        ++p)
2762     {
2763       Symbol* sym = *p;
2764       gold_assert(sym->is_forced_local());
2765       if (this->sized_finalize_symbol<size>(sym))
2766 	{
2767 	  this->add_to_final_symtab<size>(sym, pool, &index, &off);
2768 	  ++*plocal_symcount;
2769 	  if (sym->type() == elfcpp::STT_GNU_IFUNC)
2770 	    this->set_has_gnu_output();
2771 	}
2772     }
2773 
2774   // Now do all the remaining symbols.
2775   for (Symbol_table_type::iterator p = this->table_.begin();
2776        p != this->table_.end();
2777        ++p)
2778     {
2779       Symbol* sym = p->second;
2780       if (this->sized_finalize_symbol<size>(sym))
2781 	{
2782 	  this->add_to_final_symtab<size>(sym, pool, &index, &off);
2783 	  if (sym->type() == elfcpp::STT_GNU_IFUNC
2784 	      || (sym->binding() == elfcpp::STB_GNU_UNIQUE
2785 		  && parameters->options().gnu_unique()))
2786 	    this->set_has_gnu_output();
2787 	}
2788     }
2789 
2790   // Now do target-specific symbols.
2791   for (std::vector<Symbol*>::iterator p = this->target_symbols_.begin();
2792        p != this->target_symbols_.end();
2793        ++p)
2794     {
2795       this->add_to_final_symtab<size>(*p, pool, &index, &off);
2796     }
2797 
2798   this->output_count_ = index - orig_index;
2799 
2800   return off;
2801 }
2802 
2803 // Compute the final value of SYM and store status in location PSTATUS.
2804 // During relaxation, this may be called multiple times for a symbol to
2805 // compute its would-be final value in each relaxation pass.
2806 
2807 template<int size>
2808 typename Sized_symbol<size>::Value_type
compute_final_value(const Sized_symbol<size> * sym,Compute_final_value_status * pstatus) const2809 Symbol_table::compute_final_value(
2810     const Sized_symbol<size>* sym,
2811     Compute_final_value_status* pstatus) const
2812 {
2813   typedef typename Sized_symbol<size>::Value_type Value_type;
2814   Value_type value;
2815 
2816   switch (sym->source())
2817     {
2818     case Symbol::FROM_OBJECT:
2819       {
2820 	bool is_ordinary;
2821 	unsigned int shndx = sym->shndx(&is_ordinary);
2822 
2823 	if (!is_ordinary
2824 	    && shndx != elfcpp::SHN_ABS
2825 	    && !Symbol::is_common_shndx(shndx))
2826 	  {
2827 	    *pstatus = CFVS_UNSUPPORTED_SYMBOL_SECTION;
2828 	    return 0;
2829 	  }
2830 
2831 	Object* symobj = sym->object();
2832 	if (symobj->is_dynamic())
2833 	  {
2834 	    value = 0;
2835 	    shndx = elfcpp::SHN_UNDEF;
2836 	  }
2837 	else if (symobj->pluginobj() != NULL)
2838 	  {
2839 	    value = 0;
2840 	    shndx = elfcpp::SHN_UNDEF;
2841 	  }
2842 	else if (shndx == elfcpp::SHN_UNDEF)
2843 	  value = 0;
2844 	else if (!is_ordinary
2845 		 && (shndx == elfcpp::SHN_ABS
2846 		     || Symbol::is_common_shndx(shndx)))
2847 	  value = sym->value();
2848 	else
2849 	  {
2850 	    Relobj* relobj = static_cast<Relobj*>(symobj);
2851 	    Output_section* os = relobj->output_section(shndx);
2852 
2853             if (this->is_section_folded(relobj, shndx))
2854               {
2855                 gold_assert(os == NULL);
2856                 // Get the os of the section it is folded onto.
2857                 Section_id folded = this->icf_->get_folded_section(relobj,
2858                                                                    shndx);
2859                 gold_assert(folded.first != NULL);
2860                 Relobj* folded_obj = reinterpret_cast<Relobj*>(folded.first);
2861 		unsigned folded_shndx = folded.second;
2862 
2863                 os = folded_obj->output_section(folded_shndx);
2864                 gold_assert(os != NULL);
2865 
2866 		// Replace (relobj, shndx) with canonical ICF input section.
2867 		shndx = folded_shndx;
2868 		relobj = folded_obj;
2869               }
2870 
2871             uint64_t secoff64 = relobj->output_section_offset(shndx);
2872  	    if (os == NULL)
2873 	      {
2874                 bool static_or_reloc = (parameters->doing_static_link() ||
2875                                         parameters->options().relocatable());
2876                 gold_assert(static_or_reloc || sym->dynsym_index() == -1U);
2877 
2878 		*pstatus = CFVS_NO_OUTPUT_SECTION;
2879 		return 0;
2880 	      }
2881 
2882             if (secoff64 == -1ULL)
2883               {
2884                 // The section needs special handling (e.g., a merge section).
2885 
2886 	        value = os->output_address(relobj, shndx, sym->value());
2887 	      }
2888             else
2889               {
2890                 Value_type secoff =
2891                   convert_types<Value_type, uint64_t>(secoff64);
2892 	        if (sym->type() == elfcpp::STT_TLS)
2893 	          value = sym->value() + os->tls_offset() + secoff;
2894 	        else
2895 	          value = sym->value() + os->address() + secoff;
2896 	      }
2897 	  }
2898       }
2899       break;
2900 
2901     case Symbol::IN_OUTPUT_DATA:
2902       {
2903 	Output_data* od = sym->output_data();
2904 	value = sym->value();
2905 	if (sym->type() != elfcpp::STT_TLS)
2906 	  value += od->address();
2907 	else
2908 	  {
2909 	    Output_section* os = od->output_section();
2910 	    gold_assert(os != NULL);
2911 	    value += os->tls_offset() + (od->address() - os->address());
2912 	  }
2913 	if (sym->offset_is_from_end())
2914 	  value += od->data_size();
2915       }
2916       break;
2917 
2918     case Symbol::IN_OUTPUT_SEGMENT:
2919       {
2920 	Output_segment* os = sym->output_segment();
2921 	value = sym->value();
2922         if (sym->type() != elfcpp::STT_TLS)
2923 	  value += os->vaddr();
2924 	switch (sym->offset_base())
2925 	  {
2926 	  case Symbol::SEGMENT_START:
2927 	    break;
2928 	  case Symbol::SEGMENT_END:
2929 	    value += os->memsz();
2930 	    break;
2931 	  case Symbol::SEGMENT_BSS:
2932 	    value += os->filesz();
2933 	    break;
2934 	  default:
2935 	    gold_unreachable();
2936 	  }
2937       }
2938       break;
2939 
2940     case Symbol::IS_CONSTANT:
2941       value = sym->value();
2942       break;
2943 
2944     case Symbol::IS_UNDEFINED:
2945       value = 0;
2946       break;
2947 
2948     default:
2949       gold_unreachable();
2950     }
2951 
2952   *pstatus = CFVS_OK;
2953   return value;
2954 }
2955 
2956 // Finalize the symbol SYM.  This returns true if the symbol should be
2957 // added to the symbol table, false otherwise.
2958 
2959 template<int size>
2960 bool
sized_finalize_symbol(Symbol * unsized_sym)2961 Symbol_table::sized_finalize_symbol(Symbol* unsized_sym)
2962 {
2963   typedef typename Sized_symbol<size>::Value_type Value_type;
2964 
2965   Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(unsized_sym);
2966 
2967   // The default version of a symbol may appear twice in the symbol
2968   // table.  We only need to finalize it once.
2969   if (sym->has_symtab_index())
2970     return false;
2971 
2972   if (!sym->in_reg())
2973     {
2974       gold_assert(!sym->has_symtab_index());
2975       sym->set_symtab_index(-1U);
2976       gold_assert(sym->dynsym_index() == -1U);
2977       return false;
2978     }
2979 
2980   // If the symbol is only present on plugin files, the plugin decided we
2981   // don't need it.
2982   if (!sym->in_real_elf())
2983     {
2984       gold_assert(!sym->has_symtab_index());
2985       sym->set_symtab_index(-1U);
2986       return false;
2987     }
2988 
2989   // Compute final symbol value.
2990   Compute_final_value_status status;
2991   Value_type value = this->compute_final_value(sym, &status);
2992 
2993   switch (status)
2994     {
2995     case CFVS_OK:
2996       break;
2997     case CFVS_UNSUPPORTED_SYMBOL_SECTION:
2998       {
2999 	bool is_ordinary;
3000 	unsigned int shndx = sym->shndx(&is_ordinary);
3001 	gold_error(_("%s: unsupported symbol section 0x%x"),
3002 		   sym->demangled_name().c_str(), shndx);
3003       }
3004       break;
3005     case CFVS_NO_OUTPUT_SECTION:
3006       sym->set_symtab_index(-1U);
3007       return false;
3008     default:
3009       gold_unreachable();
3010     }
3011 
3012   sym->set_value(value);
3013 
3014   if (parameters->options().strip_all()
3015       || !parameters->options().should_retain_symbol(sym->name()))
3016     {
3017       sym->set_symtab_index(-1U);
3018       return false;
3019     }
3020 
3021   return true;
3022 }
3023 
3024 // Write out the global symbols.
3025 
3026 void
write_globals(const Stringpool * sympool,const Stringpool * dynpool,Output_symtab_xindex * symtab_xindex,Output_symtab_xindex * dynsym_xindex,Output_file * of) const3027 Symbol_table::write_globals(const Stringpool* sympool,
3028 			    const Stringpool* dynpool,
3029 			    Output_symtab_xindex* symtab_xindex,
3030 			    Output_symtab_xindex* dynsym_xindex,
3031 			    Output_file* of) const
3032 {
3033   switch (parameters->size_and_endianness())
3034     {
3035 #ifdef HAVE_TARGET_32_LITTLE
3036     case Parameters::TARGET_32_LITTLE:
3037       this->sized_write_globals<32, false>(sympool, dynpool, symtab_xindex,
3038 					   dynsym_xindex, of);
3039       break;
3040 #endif
3041 #ifdef HAVE_TARGET_32_BIG
3042     case Parameters::TARGET_32_BIG:
3043       this->sized_write_globals<32, true>(sympool, dynpool, symtab_xindex,
3044 					  dynsym_xindex, of);
3045       break;
3046 #endif
3047 #ifdef HAVE_TARGET_64_LITTLE
3048     case Parameters::TARGET_64_LITTLE:
3049       this->sized_write_globals<64, false>(sympool, dynpool, symtab_xindex,
3050 					   dynsym_xindex, of);
3051       break;
3052 #endif
3053 #ifdef HAVE_TARGET_64_BIG
3054     case Parameters::TARGET_64_BIG:
3055       this->sized_write_globals<64, true>(sympool, dynpool, symtab_xindex,
3056 					  dynsym_xindex, of);
3057       break;
3058 #endif
3059     default:
3060       gold_unreachable();
3061     }
3062 }
3063 
3064 // Write out the global symbols.
3065 
3066 template<int size, bool big_endian>
3067 void
sized_write_globals(const Stringpool * sympool,const Stringpool * dynpool,Output_symtab_xindex * symtab_xindex,Output_symtab_xindex * dynsym_xindex,Output_file * of) const3068 Symbol_table::sized_write_globals(const Stringpool* sympool,
3069 				  const Stringpool* dynpool,
3070 				  Output_symtab_xindex* symtab_xindex,
3071 				  Output_symtab_xindex* dynsym_xindex,
3072 				  Output_file* of) const
3073 {
3074   const Target& target = parameters->target();
3075 
3076   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
3077 
3078   const unsigned int output_count = this->output_count_;
3079   const section_size_type oview_size = output_count * sym_size;
3080   const unsigned int first_global_index = this->first_global_index_;
3081   unsigned char* psyms;
3082   if (this->offset_ == 0 || output_count == 0)
3083     psyms = NULL;
3084   else
3085     psyms = of->get_output_view(this->offset_, oview_size);
3086 
3087   const unsigned int dynamic_count = this->dynamic_count_;
3088   const section_size_type dynamic_size = dynamic_count * sym_size;
3089   const unsigned int first_dynamic_global_index =
3090     this->first_dynamic_global_index_;
3091   unsigned char* dynamic_view;
3092   if (this->dynamic_offset_ == 0 || dynamic_count == 0)
3093     dynamic_view = NULL;
3094   else
3095     dynamic_view = of->get_output_view(this->dynamic_offset_, dynamic_size);
3096 
3097   for (Symbol_table_type::const_iterator p = this->table_.begin();
3098        p != this->table_.end();
3099        ++p)
3100     {
3101       Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(p->second);
3102 
3103       // Possibly warn about unresolved symbols in shared libraries.
3104       this->warn_about_undefined_dynobj_symbol(sym);
3105 
3106       unsigned int sym_index = sym->symtab_index();
3107       unsigned int dynsym_index;
3108       if (dynamic_view == NULL)
3109 	dynsym_index = -1U;
3110       else
3111 	dynsym_index = sym->dynsym_index();
3112 
3113       if (sym_index == -1U && dynsym_index == -1U)
3114 	{
3115 	  // This symbol is not included in the output file.
3116 	  continue;
3117 	}
3118 
3119       unsigned int shndx;
3120       typename elfcpp::Elf_types<size>::Elf_Addr sym_value = sym->value();
3121       typename elfcpp::Elf_types<size>::Elf_Addr dynsym_value = sym_value;
3122       elfcpp::STB binding = sym->binding();
3123 
3124       // If --weak-unresolved-symbols is set, change binding of unresolved
3125       // global symbols to STB_WEAK.
3126       if (parameters->options().weak_unresolved_symbols()
3127 	  && binding == elfcpp::STB_GLOBAL
3128 	  && sym->is_undefined())
3129 	binding = elfcpp::STB_WEAK;
3130 
3131       // If --no-gnu-unique is set, change STB_GNU_UNIQUE to STB_GLOBAL.
3132       if (binding == elfcpp::STB_GNU_UNIQUE
3133 	  && !parameters->options().gnu_unique())
3134 	binding = elfcpp::STB_GLOBAL;
3135 
3136       switch (sym->source())
3137 	{
3138 	case Symbol::FROM_OBJECT:
3139 	  {
3140 	    bool is_ordinary;
3141 	    unsigned int in_shndx = sym->shndx(&is_ordinary);
3142 
3143 	    if (!is_ordinary
3144 		&& in_shndx != elfcpp::SHN_ABS
3145 		&& !Symbol::is_common_shndx(in_shndx))
3146 	      {
3147 		gold_error(_("%s: unsupported symbol section 0x%x"),
3148 			   sym->demangled_name().c_str(), in_shndx);
3149 		shndx = in_shndx;
3150 	      }
3151 	    else
3152 	      {
3153 		Object* symobj = sym->object();
3154 		if (symobj->is_dynamic())
3155 		  {
3156 		    if (sym->needs_dynsym_value())
3157 		      dynsym_value = target.dynsym_value(sym);
3158 		    shndx = elfcpp::SHN_UNDEF;
3159 		    if (sym->is_undef_binding_weak())
3160 		      binding = elfcpp::STB_WEAK;
3161 		    else
3162 		      binding = elfcpp::STB_GLOBAL;
3163 		  }
3164 		else if (symobj->pluginobj() != NULL)
3165 		  shndx = elfcpp::SHN_UNDEF;
3166 		else if (in_shndx == elfcpp::SHN_UNDEF
3167 			 || (!is_ordinary
3168 			     && (in_shndx == elfcpp::SHN_ABS
3169 				 || Symbol::is_common_shndx(in_shndx))))
3170 		  shndx = in_shndx;
3171 		else
3172 		  {
3173 		    Relobj* relobj = static_cast<Relobj*>(symobj);
3174 		    Output_section* os = relobj->output_section(in_shndx);
3175                     if (this->is_section_folded(relobj, in_shndx))
3176                       {
3177                         // This global symbol must be written out even though
3178                         // it is folded.
3179                         // Get the os of the section it is folded onto.
3180                         Section_id folded =
3181                              this->icf_->get_folded_section(relobj, in_shndx);
3182                         gold_assert(folded.first !=NULL);
3183                         Relobj* folded_obj =
3184                           reinterpret_cast<Relobj*>(folded.first);
3185                         os = folded_obj->output_section(folded.second);
3186                         gold_assert(os != NULL);
3187                       }
3188 		    gold_assert(os != NULL);
3189 		    shndx = os->out_shndx();
3190 
3191 		    if (shndx >= elfcpp::SHN_LORESERVE)
3192 		      {
3193 			if (sym_index != -1U)
3194 			  symtab_xindex->add(sym_index, shndx);
3195 			if (dynsym_index != -1U)
3196 			  dynsym_xindex->add(dynsym_index, shndx);
3197 			shndx = elfcpp::SHN_XINDEX;
3198 		      }
3199 
3200 		    // In object files symbol values are section
3201 		    // relative.
3202 		    if (parameters->options().relocatable())
3203 		      sym_value -= os->address();
3204 		  }
3205 	      }
3206 	  }
3207 	  break;
3208 
3209 	case Symbol::IN_OUTPUT_DATA:
3210 	  {
3211 	    Output_data* od = sym->output_data();
3212 
3213 	    shndx = od->out_shndx();
3214 	    if (shndx >= elfcpp::SHN_LORESERVE)
3215 	      {
3216 		if (sym_index != -1U)
3217 		  symtab_xindex->add(sym_index, shndx);
3218 		if (dynsym_index != -1U)
3219 		  dynsym_xindex->add(dynsym_index, shndx);
3220 		shndx = elfcpp::SHN_XINDEX;
3221 	      }
3222 
3223 	    // In object files symbol values are section
3224 	    // relative.
3225 	    if (parameters->options().relocatable())
3226 	      {
3227 		Output_section* os = od->output_section();
3228 		gold_assert(os != NULL);
3229 		sym_value -= os->address();
3230 	      }
3231 	  }
3232 	  break;
3233 
3234 	case Symbol::IN_OUTPUT_SEGMENT:
3235 	  {
3236 	    Output_segment* oseg = sym->output_segment();
3237 	    Output_section* osect = oseg->first_section();
3238 	    if (osect == NULL)
3239 	      shndx = elfcpp::SHN_ABS;
3240 	    else
3241 	      shndx = osect->out_shndx();
3242 	  }
3243 	  break;
3244 
3245 	case Symbol::IS_CONSTANT:
3246 	  shndx = elfcpp::SHN_ABS;
3247 	  break;
3248 
3249 	case Symbol::IS_UNDEFINED:
3250 	  shndx = elfcpp::SHN_UNDEF;
3251 	  break;
3252 
3253 	default:
3254 	  gold_unreachable();
3255 	}
3256 
3257       if (sym_index != -1U)
3258 	{
3259 	  sym_index -= first_global_index;
3260 	  gold_assert(sym_index < output_count);
3261 	  unsigned char* ps = psyms + (sym_index * sym_size);
3262 	  this->sized_write_symbol<size, big_endian>(sym, sym_value, shndx,
3263 						     binding, sympool, ps);
3264 	}
3265 
3266       if (dynsym_index != -1U)
3267 	{
3268 	  dynsym_index -= first_dynamic_global_index;
3269 	  gold_assert(dynsym_index < dynamic_count);
3270 	  unsigned char* pd = dynamic_view + (dynsym_index * sym_size);
3271 	  this->sized_write_symbol<size, big_endian>(sym, dynsym_value, shndx,
3272 						     binding, dynpool, pd);
3273           // Allow a target to adjust dynamic symbol value.
3274           parameters->target().adjust_dyn_symbol(sym, pd);
3275 	}
3276     }
3277 
3278   // Write the target-specific symbols.
3279   for (std::vector<Symbol*>::const_iterator p = this->target_symbols_.begin();
3280        p != this->target_symbols_.end();
3281        ++p)
3282     {
3283       Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(*p);
3284 
3285       unsigned int sym_index = sym->symtab_index();
3286       unsigned int dynsym_index;
3287       if (dynamic_view == NULL)
3288 	dynsym_index = -1U;
3289       else
3290 	dynsym_index = sym->dynsym_index();
3291 
3292       unsigned int shndx;
3293       switch (sym->source())
3294 	{
3295 	case Symbol::IS_CONSTANT:
3296 	  shndx = elfcpp::SHN_ABS;
3297 	  break;
3298 	case Symbol::IS_UNDEFINED:
3299 	  shndx = elfcpp::SHN_UNDEF;
3300 	  break;
3301 	default:
3302 	  gold_unreachable();
3303 	}
3304 
3305       if (sym_index != -1U)
3306 	{
3307 	  sym_index -= first_global_index;
3308 	  gold_assert(sym_index < output_count);
3309 	  unsigned char* ps = psyms + (sym_index * sym_size);
3310 	  this->sized_write_symbol<size, big_endian>(sym, sym->value(), shndx,
3311 						     sym->binding(), sympool,
3312 						     ps);
3313 	}
3314 
3315       if (dynsym_index != -1U)
3316 	{
3317 	  dynsym_index -= first_dynamic_global_index;
3318 	  gold_assert(dynsym_index < dynamic_count);
3319 	  unsigned char* pd = dynamic_view + (dynsym_index * sym_size);
3320 	  this->sized_write_symbol<size, big_endian>(sym, sym->value(), shndx,
3321 						     sym->binding(), dynpool,
3322 						     pd);
3323 	}
3324     }
3325 
3326   of->write_output_view(this->offset_, oview_size, psyms);
3327   if (dynamic_view != NULL)
3328     of->write_output_view(this->dynamic_offset_, dynamic_size, dynamic_view);
3329 }
3330 
3331 // Write out the symbol SYM, in section SHNDX, to P.  POOL is the
3332 // strtab holding the name.
3333 
3334 template<int size, bool big_endian>
3335 void
sized_write_symbol(Sized_symbol<size> * sym,typename elfcpp::Elf_types<size>::Elf_Addr value,unsigned int shndx,elfcpp::STB binding,const Stringpool * pool,unsigned char * p) const3336 Symbol_table::sized_write_symbol(
3337     Sized_symbol<size>* sym,
3338     typename elfcpp::Elf_types<size>::Elf_Addr value,
3339     unsigned int shndx,
3340     elfcpp::STB binding,
3341     const Stringpool* pool,
3342     unsigned char* p) const
3343 {
3344   elfcpp::Sym_write<size, big_endian> osym(p);
3345   if (sym->version() == NULL || !parameters->options().relocatable())
3346     osym.put_st_name(pool->get_offset(sym->name()));
3347   else
3348     osym.put_st_name(pool->get_offset(sym->versioned_name()));
3349   osym.put_st_value(value);
3350   // Use a symbol size of zero for undefined symbols from shared libraries.
3351   if (shndx == elfcpp::SHN_UNDEF && sym->is_from_dynobj())
3352     osym.put_st_size(0);
3353   else
3354     osym.put_st_size(sym->symsize());
3355   elfcpp::STT type = sym->type();
3356   gold_assert(type != elfcpp::STT_GNU_IFUNC || !sym->is_from_dynobj());
3357   // A version script may have overridden the default binding.
3358   if (sym->is_forced_local())
3359     osym.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL, type));
3360   else
3361     osym.put_st_info(elfcpp::elf_st_info(binding, type));
3362   osym.put_st_other(elfcpp::elf_st_other(sym->visibility(), sym->nonvis()));
3363   osym.put_st_shndx(shndx);
3364 }
3365 
3366 // Check for unresolved symbols in shared libraries.  This is
3367 // controlled by the --allow-shlib-undefined option.
3368 
3369 // We only warn about libraries for which we have seen all the
3370 // DT_NEEDED entries.  We don't try to track down DT_NEEDED entries
3371 // which were not seen in this link.  If we didn't see a DT_NEEDED
3372 // entry, we aren't going to be able to reliably report whether the
3373 // symbol is undefined.
3374 
3375 // We also don't warn about libraries found in a system library
3376 // directory (e.g., /lib or /usr/lib); we assume that those libraries
3377 // are OK.  This heuristic avoids problems on GNU/Linux, in which -ldl
3378 // can have undefined references satisfied by ld-linux.so.
3379 
3380 inline void
warn_about_undefined_dynobj_symbol(Symbol * sym) const3381 Symbol_table::warn_about_undefined_dynobj_symbol(Symbol* sym) const
3382 {
3383   bool dummy;
3384   if (sym->source() == Symbol::FROM_OBJECT
3385       && sym->object()->is_dynamic()
3386       && sym->shndx(&dummy) == elfcpp::SHN_UNDEF
3387       && sym->binding() != elfcpp::STB_WEAK
3388       && !parameters->options().allow_shlib_undefined()
3389       && !parameters->target().is_defined_by_abi(sym)
3390       && !sym->object()->is_in_system_directory())
3391     {
3392       // A very ugly cast.
3393       Dynobj* dynobj = static_cast<Dynobj*>(sym->object());
3394       if (!dynobj->has_unknown_needed_entries())
3395         gold_undefined_symbol(sym);
3396     }
3397 }
3398 
3399 // Write out a section symbol.  Return the update offset.
3400 
3401 void
write_section_symbol(const Output_section * os,Output_symtab_xindex * symtab_xindex,Output_file * of,off_t offset) const3402 Symbol_table::write_section_symbol(const Output_section* os,
3403 				   Output_symtab_xindex* symtab_xindex,
3404 				   Output_file* of,
3405 				   off_t offset) const
3406 {
3407   switch (parameters->size_and_endianness())
3408     {
3409 #ifdef HAVE_TARGET_32_LITTLE
3410     case Parameters::TARGET_32_LITTLE:
3411       this->sized_write_section_symbol<32, false>(os, symtab_xindex, of,
3412 						  offset);
3413       break;
3414 #endif
3415 #ifdef HAVE_TARGET_32_BIG
3416     case Parameters::TARGET_32_BIG:
3417       this->sized_write_section_symbol<32, true>(os, symtab_xindex, of,
3418 						 offset);
3419       break;
3420 #endif
3421 #ifdef HAVE_TARGET_64_LITTLE
3422     case Parameters::TARGET_64_LITTLE:
3423       this->sized_write_section_symbol<64, false>(os, symtab_xindex, of,
3424 						  offset);
3425       break;
3426 #endif
3427 #ifdef HAVE_TARGET_64_BIG
3428     case Parameters::TARGET_64_BIG:
3429       this->sized_write_section_symbol<64, true>(os, symtab_xindex, of,
3430 						 offset);
3431       break;
3432 #endif
3433     default:
3434       gold_unreachable();
3435     }
3436 }
3437 
3438 // Write out a section symbol, specialized for size and endianness.
3439 
3440 template<int size, bool big_endian>
3441 void
sized_write_section_symbol(const Output_section * os,Output_symtab_xindex * symtab_xindex,Output_file * of,off_t offset) const3442 Symbol_table::sized_write_section_symbol(const Output_section* os,
3443 					 Output_symtab_xindex* symtab_xindex,
3444 					 Output_file* of,
3445 					 off_t offset) const
3446 {
3447   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
3448 
3449   unsigned char* pov = of->get_output_view(offset, sym_size);
3450 
3451   elfcpp::Sym_write<size, big_endian> osym(pov);
3452   osym.put_st_name(0);
3453   if (parameters->options().relocatable())
3454     osym.put_st_value(0);
3455   else
3456     osym.put_st_value(os->address());
3457   osym.put_st_size(0);
3458   osym.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL,
3459 				       elfcpp::STT_SECTION));
3460   osym.put_st_other(elfcpp::elf_st_other(elfcpp::STV_DEFAULT, 0));
3461 
3462   unsigned int shndx = os->out_shndx();
3463   if (shndx >= elfcpp::SHN_LORESERVE)
3464     {
3465       symtab_xindex->add(os->symtab_index(), shndx);
3466       shndx = elfcpp::SHN_XINDEX;
3467     }
3468   osym.put_st_shndx(shndx);
3469 
3470   of->write_output_view(offset, sym_size, pov);
3471 }
3472 
3473 // Print statistical information to stderr.  This is used for --stats.
3474 
3475 void
print_stats() const3476 Symbol_table::print_stats() const
3477 {
3478 #if defined(HAVE_TR1_UNORDERED_MAP) || defined(HAVE_EXT_HASH_MAP)
3479   fprintf(stderr, _("%s: symbol table entries: %zu; buckets: %zu\n"),
3480 	  program_name, this->table_.size(), this->table_.bucket_count());
3481 #else
3482   fprintf(stderr, _("%s: symbol table entries: %zu\n"),
3483 	  program_name, this->table_.size());
3484 #endif
3485   this->namepool_.print_stats("symbol table stringpool");
3486 }
3487 
3488 // We check for ODR violations by looking for symbols with the same
3489 // name for which the debugging information reports that they were
3490 // defined in disjoint source locations.  When comparing the source
3491 // location, we consider instances with the same base filename to be
3492 // the same.  This is because different object files/shared libraries
3493 // can include the same header file using different paths, and
3494 // different optimization settings can make the line number appear to
3495 // be a couple lines off, and we don't want to report an ODR violation
3496 // in those cases.
3497 
3498 // This struct is used to compare line information, as returned by
3499 // Dwarf_line_info::one_addr2line.  It implements a < comparison
3500 // operator used with std::sort.
3501 
3502 struct Odr_violation_compare
3503 {
3504   bool
operator ()gold::Odr_violation_compare3505   operator()(const std::string& s1, const std::string& s2) const
3506   {
3507     // Inputs should be of the form "dirname/filename:linenum" where
3508     // "dirname/" is optional.  We want to compare just the filename:linenum.
3509 
3510     // Find the last '/' in each string.
3511     std::string::size_type s1begin = s1.rfind('/');
3512     std::string::size_type s2begin = s2.rfind('/');
3513     // If there was no '/' in a string, start at the beginning.
3514     if (s1begin == std::string::npos)
3515       s1begin = 0;
3516     if (s2begin == std::string::npos)
3517       s2begin = 0;
3518     return s1.compare(s1begin, std::string::npos,
3519 		      s2, s2begin, std::string::npos) < 0;
3520   }
3521 };
3522 
3523 // Returns all of the lines attached to LOC, not just the one the
3524 // instruction actually came from.
3525 std::vector<std::string>
linenos_from_loc(const Task * task,const Symbol_location & loc)3526 Symbol_table::linenos_from_loc(const Task* task,
3527                                const Symbol_location& loc)
3528 {
3529   // We need to lock the object in order to read it.  This
3530   // means that we have to run in a singleton Task.  If we
3531   // want to run this in a general Task for better
3532   // performance, we will need one Task for object, plus
3533   // appropriate locking to ensure that we don't conflict with
3534   // other uses of the object.  Also note, one_addr2line is not
3535   // currently thread-safe.
3536   Task_lock_obj<Object> tl(task, loc.object);
3537 
3538   std::vector<std::string> result;
3539   Symbol_location code_loc = loc;
3540   parameters->target().function_location(&code_loc);
3541   // 16 is the size of the object-cache that one_addr2line should use.
3542   std::string canonical_result = Dwarf_line_info::one_addr2line(
3543       code_loc.object, code_loc.shndx, code_loc.offset, 16, &result);
3544   if (!canonical_result.empty())
3545     result.push_back(canonical_result);
3546   return result;
3547 }
3548 
3549 // OutputIterator that records if it was ever assigned to.  This
3550 // allows it to be used with std::set_intersection() to check for
3551 // intersection rather than computing the intersection.
3552 struct Check_intersection
3553 {
Check_intersectiongold::Check_intersection3554   Check_intersection()
3555     : value_(false)
3556   {}
3557 
had_intersectiongold::Check_intersection3558   bool had_intersection() const
3559   { return this->value_; }
3560 
operator ++gold::Check_intersection3561   Check_intersection& operator++()
3562   { return *this; }
3563 
operator *gold::Check_intersection3564   Check_intersection& operator*()
3565   { return *this; }
3566 
3567   template<typename T>
operator =gold::Check_intersection3568   Check_intersection& operator=(const T&)
3569   {
3570     this->value_ = true;
3571     return *this;
3572   }
3573 
3574  private:
3575   bool value_;
3576 };
3577 
3578 // Check candidate_odr_violations_ to find symbols with the same name
3579 // but apparently different definitions (different source-file/line-no
3580 // for each line assigned to the first instruction).
3581 
3582 void
detect_odr_violations(const Task * task,const char * output_file_name) const3583 Symbol_table::detect_odr_violations(const Task* task,
3584 				    const char* output_file_name) const
3585 {
3586   for (Odr_map::const_iterator it = candidate_odr_violations_.begin();
3587        it != candidate_odr_violations_.end();
3588        ++it)
3589     {
3590       const char* const symbol_name = it->first;
3591 
3592       std::string first_object_name;
3593       std::vector<std::string> first_object_linenos;
3594 
3595       Unordered_set<Symbol_location, Symbol_location_hash>::const_iterator
3596           locs = it->second.begin();
3597       const Unordered_set<Symbol_location, Symbol_location_hash>::const_iterator
3598           locs_end = it->second.end();
3599       for (; locs != locs_end && first_object_linenos.empty(); ++locs)
3600         {
3601           // Save the line numbers from the first definition to
3602           // compare to the other definitions.  Ideally, we'd compare
3603           // every definition to every other, but we don't want to
3604           // take O(N^2) time to do this.  This shortcut may cause
3605           // false negatives that appear or disappear depending on the
3606           // link order, but it won't cause false positives.
3607           first_object_name = locs->object->name();
3608           first_object_linenos = this->linenos_from_loc(task, *locs);
3609         }
3610       if (first_object_linenos.empty())
3611 	continue;
3612 
3613       // Sort by Odr_violation_compare to make std::set_intersection work.
3614       std::string first_object_canonical_result = first_object_linenos.back();
3615       std::sort(first_object_linenos.begin(), first_object_linenos.end(),
3616                 Odr_violation_compare());
3617 
3618       for (; locs != locs_end; ++locs)
3619         {
3620           std::vector<std::string> linenos =
3621               this->linenos_from_loc(task, *locs);
3622           // linenos will be empty if we couldn't parse the debug info.
3623           if (linenos.empty())
3624             continue;
3625           // Sort by Odr_violation_compare to make std::set_intersection work.
3626           gold_assert(!linenos.empty());
3627           std::string second_object_canonical_result = linenos.back();
3628           std::sort(linenos.begin(), linenos.end(), Odr_violation_compare());
3629 
3630           Check_intersection intersection_result =
3631               std::set_intersection(first_object_linenos.begin(),
3632                                     first_object_linenos.end(),
3633                                     linenos.begin(),
3634                                     linenos.end(),
3635                                     Check_intersection(),
3636                                     Odr_violation_compare());
3637           if (!intersection_result.had_intersection())
3638             {
3639               gold_warning(_("while linking %s: symbol '%s' defined in "
3640                              "multiple places (possible ODR violation):"),
3641                            output_file_name, demangle(symbol_name).c_str());
3642               // This only prints one location from each definition,
3643               // which may not be the location we expect to intersect
3644               // with another definition.  We could print the whole
3645               // set of locations, but that seems too verbose.
3646               fprintf(stderr, _("  %s from %s\n"),
3647                       first_object_canonical_result.c_str(),
3648                       first_object_name.c_str());
3649               fprintf(stderr, _("  %s from %s\n"),
3650                       second_object_canonical_result.c_str(),
3651                       locs->object->name().c_str());
3652               // Only print one broken pair, to avoid needing to
3653               // compare against a list of the disjoint definition
3654               // locations we've found so far.  (If we kept comparing
3655               // against just the first one, we'd get a lot of
3656               // redundant complaints about the second definition
3657               // location.)
3658               break;
3659             }
3660         }
3661     }
3662   // We only call one_addr2line() in this function, so we can clear its cache.
3663   Dwarf_line_info::clear_addr2line_cache();
3664 }
3665 
3666 // Warnings functions.
3667 
3668 // Add a new warning.
3669 
3670 void
add_warning(Symbol_table * symtab,const char * name,Object * obj,const std::string & warning)3671 Warnings::add_warning(Symbol_table* symtab, const char* name, Object* obj,
3672 		      const std::string& warning)
3673 {
3674   name = symtab->canonicalize_name(name);
3675   this->warnings_[name].set(obj, warning);
3676 }
3677 
3678 // Look through the warnings and mark the symbols for which we should
3679 // warn.  This is called during Layout::finalize when we know the
3680 // sources for all the symbols.
3681 
3682 void
note_warnings(Symbol_table * symtab)3683 Warnings::note_warnings(Symbol_table* symtab)
3684 {
3685   for (Warning_table::iterator p = this->warnings_.begin();
3686        p != this->warnings_.end();
3687        ++p)
3688     {
3689       Symbol* sym = symtab->lookup(p->first, NULL);
3690       if (sym != NULL
3691 	  && sym->source() == Symbol::FROM_OBJECT
3692 	  && sym->object() == p->second.object)
3693 	sym->set_has_warning();
3694     }
3695 }
3696 
3697 // Issue a warning.  This is called when we see a relocation against a
3698 // symbol for which has a warning.
3699 
3700 template<int size, bool big_endian>
3701 void
issue_warning(const Symbol * sym,const Relocate_info<size,big_endian> * relinfo,size_t relnum,off_t reloffset) const3702 Warnings::issue_warning(const Symbol* sym,
3703 			const Relocate_info<size, big_endian>* relinfo,
3704 			size_t relnum, off_t reloffset) const
3705 {
3706   gold_assert(sym->has_warning());
3707 
3708   // We don't want to issue a warning for a relocation against the
3709   // symbol in the same object file in which the symbol is defined.
3710   if (sym->object() == relinfo->object)
3711     return;
3712 
3713   Warning_table::const_iterator p = this->warnings_.find(sym->name());
3714   gold_assert(p != this->warnings_.end());
3715   gold_warning_at_location(relinfo, relnum, reloffset,
3716 			   "%s", p->second.text.c_str());
3717 }
3718 
3719 // Instantiate the templates we need.  We could use the configure
3720 // script to restrict this to only the ones needed for implemented
3721 // targets.
3722 
3723 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3724 template
3725 void
3726 Sized_symbol<32>::allocate_common(Output_data*, Value_type);
3727 #endif
3728 
3729 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3730 template
3731 void
3732 Sized_symbol<64>::allocate_common(Output_data*, Value_type);
3733 #endif
3734 
3735 #ifdef HAVE_TARGET_32_LITTLE
3736 template
3737 void
3738 Symbol_table::add_from_relobj<32, false>(
3739     Sized_relobj_file<32, false>* relobj,
3740     const unsigned char* syms,
3741     size_t count,
3742     size_t symndx_offset,
3743     const char* sym_names,
3744     size_t sym_name_size,
3745     Sized_relobj_file<32, false>::Symbols* sympointers,
3746     size_t* defined);
3747 #endif
3748 
3749 #ifdef HAVE_TARGET_32_BIG
3750 template
3751 void
3752 Symbol_table::add_from_relobj<32, true>(
3753     Sized_relobj_file<32, true>* relobj,
3754     const unsigned char* syms,
3755     size_t count,
3756     size_t symndx_offset,
3757     const char* sym_names,
3758     size_t sym_name_size,
3759     Sized_relobj_file<32, true>::Symbols* sympointers,
3760     size_t* defined);
3761 #endif
3762 
3763 #ifdef HAVE_TARGET_64_LITTLE
3764 template
3765 void
3766 Symbol_table::add_from_relobj<64, false>(
3767     Sized_relobj_file<64, false>* relobj,
3768     const unsigned char* syms,
3769     size_t count,
3770     size_t symndx_offset,
3771     const char* sym_names,
3772     size_t sym_name_size,
3773     Sized_relobj_file<64, false>::Symbols* sympointers,
3774     size_t* defined);
3775 #endif
3776 
3777 #ifdef HAVE_TARGET_64_BIG
3778 template
3779 void
3780 Symbol_table::add_from_relobj<64, true>(
3781     Sized_relobj_file<64, true>* relobj,
3782     const unsigned char* syms,
3783     size_t count,
3784     size_t symndx_offset,
3785     const char* sym_names,
3786     size_t sym_name_size,
3787     Sized_relobj_file<64, true>::Symbols* sympointers,
3788     size_t* defined);
3789 #endif
3790 
3791 #ifdef HAVE_TARGET_32_LITTLE
3792 template
3793 Symbol*
3794 Symbol_table::add_from_pluginobj<32, false>(
3795     Sized_pluginobj<32, false>* obj,
3796     const char* name,
3797     const char* ver,
3798     elfcpp::Sym<32, false>* sym);
3799 #endif
3800 
3801 #ifdef HAVE_TARGET_32_BIG
3802 template
3803 Symbol*
3804 Symbol_table::add_from_pluginobj<32, true>(
3805     Sized_pluginobj<32, true>* obj,
3806     const char* name,
3807     const char* ver,
3808     elfcpp::Sym<32, true>* sym);
3809 #endif
3810 
3811 #ifdef HAVE_TARGET_64_LITTLE
3812 template
3813 Symbol*
3814 Symbol_table::add_from_pluginobj<64, false>(
3815     Sized_pluginobj<64, false>* obj,
3816     const char* name,
3817     const char* ver,
3818     elfcpp::Sym<64, false>* sym);
3819 #endif
3820 
3821 #ifdef HAVE_TARGET_64_BIG
3822 template
3823 Symbol*
3824 Symbol_table::add_from_pluginobj<64, true>(
3825     Sized_pluginobj<64, true>* obj,
3826     const char* name,
3827     const char* ver,
3828     elfcpp::Sym<64, true>* sym);
3829 #endif
3830 
3831 #ifdef HAVE_TARGET_32_LITTLE
3832 template
3833 void
3834 Symbol_table::add_from_dynobj<32, false>(
3835     Sized_dynobj<32, false>* dynobj,
3836     const unsigned char* syms,
3837     size_t count,
3838     const char* sym_names,
3839     size_t sym_name_size,
3840     const unsigned char* versym,
3841     size_t versym_size,
3842     const std::vector<const char*>* version_map,
3843     Sized_relobj_file<32, false>::Symbols* sympointers,
3844     size_t* defined);
3845 #endif
3846 
3847 #ifdef HAVE_TARGET_32_BIG
3848 template
3849 void
3850 Symbol_table::add_from_dynobj<32, true>(
3851     Sized_dynobj<32, true>* dynobj,
3852     const unsigned char* syms,
3853     size_t count,
3854     const char* sym_names,
3855     size_t sym_name_size,
3856     const unsigned char* versym,
3857     size_t versym_size,
3858     const std::vector<const char*>* version_map,
3859     Sized_relobj_file<32, true>::Symbols* sympointers,
3860     size_t* defined);
3861 #endif
3862 
3863 #ifdef HAVE_TARGET_64_LITTLE
3864 template
3865 void
3866 Symbol_table::add_from_dynobj<64, false>(
3867     Sized_dynobj<64, false>* dynobj,
3868     const unsigned char* syms,
3869     size_t count,
3870     const char* sym_names,
3871     size_t sym_name_size,
3872     const unsigned char* versym,
3873     size_t versym_size,
3874     const std::vector<const char*>* version_map,
3875     Sized_relobj_file<64, false>::Symbols* sympointers,
3876     size_t* defined);
3877 #endif
3878 
3879 #ifdef HAVE_TARGET_64_BIG
3880 template
3881 void
3882 Symbol_table::add_from_dynobj<64, true>(
3883     Sized_dynobj<64, true>* dynobj,
3884     const unsigned char* syms,
3885     size_t count,
3886     const char* sym_names,
3887     size_t sym_name_size,
3888     const unsigned char* versym,
3889     size_t versym_size,
3890     const std::vector<const char*>* version_map,
3891     Sized_relobj_file<64, true>::Symbols* sympointers,
3892     size_t* defined);
3893 #endif
3894 
3895 #ifdef HAVE_TARGET_32_LITTLE
3896 template
3897 Sized_symbol<32>*
3898 Symbol_table::add_from_incrobj(
3899     Object* obj,
3900     const char* name,
3901     const char* ver,
3902     elfcpp::Sym<32, false>* sym);
3903 #endif
3904 
3905 #ifdef HAVE_TARGET_32_BIG
3906 template
3907 Sized_symbol<32>*
3908 Symbol_table::add_from_incrobj(
3909     Object* obj,
3910     const char* name,
3911     const char* ver,
3912     elfcpp::Sym<32, true>* sym);
3913 #endif
3914 
3915 #ifdef HAVE_TARGET_64_LITTLE
3916 template
3917 Sized_symbol<64>*
3918 Symbol_table::add_from_incrobj(
3919     Object* obj,
3920     const char* name,
3921     const char* ver,
3922     elfcpp::Sym<64, false>* sym);
3923 #endif
3924 
3925 #ifdef HAVE_TARGET_64_BIG
3926 template
3927 Sized_symbol<64>*
3928 Symbol_table::add_from_incrobj(
3929     Object* obj,
3930     const char* name,
3931     const char* ver,
3932     elfcpp::Sym<64, true>* sym);
3933 #endif
3934 
3935 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3936 template
3937 void
3938 Symbol_table::define_with_copy_reloc<32>(
3939     Sized_symbol<32>* sym,
3940     Output_data* posd,
3941     elfcpp::Elf_types<32>::Elf_Addr value);
3942 #endif
3943 
3944 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3945 template
3946 void
3947 Symbol_table::define_with_copy_reloc<64>(
3948     Sized_symbol<64>* sym,
3949     Output_data* posd,
3950     elfcpp::Elf_types<64>::Elf_Addr value);
3951 #endif
3952 
3953 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3954 template
3955 void
3956 Sized_symbol<32>::init_output_data(const char* name, const char* version,
3957 				   Output_data* od, Value_type value,
3958 				   Size_type symsize, elfcpp::STT type,
3959 				   elfcpp::STB binding,
3960 				   elfcpp::STV visibility,
3961 				   unsigned char nonvis,
3962 				   bool offset_is_from_end,
3963 				   bool is_predefined);
3964 
3965 template
3966 void
3967 Sized_symbol<32>::init_constant(const char* name, const char* version,
3968 				Value_type value, Size_type symsize,
3969 				elfcpp::STT type, elfcpp::STB binding,
3970 				elfcpp::STV visibility, unsigned char nonvis,
3971 				bool is_predefined);
3972 
3973 template
3974 void
3975 Sized_symbol<32>::init_undefined(const char* name, const char* version,
3976 				 Value_type value, elfcpp::STT type,
3977 				 elfcpp::STB binding, elfcpp::STV visibility,
3978 				 unsigned char nonvis);
3979 #endif
3980 
3981 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3982 template
3983 void
3984 Sized_symbol<64>::init_output_data(const char* name, const char* version,
3985 				   Output_data* od, Value_type value,
3986 				   Size_type symsize, elfcpp::STT type,
3987 				   elfcpp::STB binding,
3988 				   elfcpp::STV visibility,
3989 				   unsigned char nonvis,
3990 				   bool offset_is_from_end,
3991 				   bool is_predefined);
3992 
3993 template
3994 void
3995 Sized_symbol<64>::init_constant(const char* name, const char* version,
3996 				Value_type value, Size_type symsize,
3997 				elfcpp::STT type, elfcpp::STB binding,
3998 				elfcpp::STV visibility, unsigned char nonvis,
3999 				bool is_predefined);
4000 
4001 template
4002 void
4003 Sized_symbol<64>::init_undefined(const char* name, const char* version,
4004 				 Value_type value, elfcpp::STT type,
4005 				 elfcpp::STB binding, elfcpp::STV visibility,
4006 				 unsigned char nonvis);
4007 #endif
4008 
4009 #ifdef HAVE_TARGET_32_LITTLE
4010 template
4011 void
4012 Warnings::issue_warning<32, false>(const Symbol* sym,
4013 				   const Relocate_info<32, false>* relinfo,
4014 				   size_t relnum, off_t reloffset) const;
4015 #endif
4016 
4017 #ifdef HAVE_TARGET_32_BIG
4018 template
4019 void
4020 Warnings::issue_warning<32, true>(const Symbol* sym,
4021 				  const Relocate_info<32, true>* relinfo,
4022 				  size_t relnum, off_t reloffset) const;
4023 #endif
4024 
4025 #ifdef HAVE_TARGET_64_LITTLE
4026 template
4027 void
4028 Warnings::issue_warning<64, false>(const Symbol* sym,
4029 				   const Relocate_info<64, false>* relinfo,
4030 				   size_t relnum, off_t reloffset) const;
4031 #endif
4032 
4033 #ifdef HAVE_TARGET_64_BIG
4034 template
4035 void
4036 Warnings::issue_warning<64, true>(const Symbol* sym,
4037 				  const Relocate_info<64, true>* relinfo,
4038 				  size_t relnum, off_t reloffset) const;
4039 #endif
4040 
4041 } // End namespace gold.
4042