bfd/libcoff-in.h

   1 /* BFD COFF object file private structure.
   2    Copyright (C) 1990-2022 Free Software Foundation, Inc.
   3    Written by Cygnus Support.
   4
   5    This file is part of BFD, the Binary File Descriptor library.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  20    MA 02110-1301, USA.  */
  21
  22 #ifndef _LIBCOFF_H
  23 #define _LIBCOFF_H 1
  24
  25 #include "bfdlink.h"
  26 #include "coff-bfd.h"
  27
  28 #ifdef __cplusplus
  29 extern "C" {
  30 #endif
  31
  32 /* Object file tdata; access macros.  */
  33
  34 #define coff_data(bfd)                ((bfd)->tdata.coff_obj_data)
  35 #define obj_pe(bfd)                   (coff_data (bfd)->pe)
  36 #define obj_go32(bfd)                 (coff_data (bfd)->go32)
  37 #define obj_symbols(bfd)              (coff_data (bfd)->symbols)
  38 #define obj_sym_filepos(bfd)          (coff_data (bfd)->sym_filepos)
  39 #define obj_relocbase(bfd)            (coff_data (bfd)->relocbase)
  40 #define obj_raw_syments(bfd)          (coff_data (bfd)->raw_syments)
  41 #define obj_raw_syment_count(bfd)     (coff_data (bfd)->raw_syment_count)
  42 #define obj_convert(bfd)              (coff_data (bfd)->conversion_table)
  43 #define obj_conv_table_size(bfd)      (coff_data (bfd)->conv_table_size)
  44 #define obj_coff_external_syms(bfd)   (coff_data (bfd)->external_syms)
  45 #define obj_coff_keep_syms(bfd)       (coff_data (bfd)->keep_syms)
  46 #define obj_coff_strings(bfd)         (coff_data (bfd)->strings)
  47 #define obj_coff_strings_len(bfd)     (coff_data (bfd)->strings_len)
  48 #define obj_coff_keep_strings(bfd)    (coff_data (bfd)->keep_strings)
  49 #define obj_coff_sym_hashes(bfd)      (coff_data (bfd)->sym_hashes)
  50 #define obj_coff_strings_written(bfd) (coff_data (bfd)->strings_written)
  51 #define obj_coff_local_toc_table(bfd) (coff_data (bfd)->local_toc_sym_map)
  52
  53 /* `Tdata' information kept for COFF files.  */
  54
  55 typedef struct coff_tdata
  56 {
  57   struct coff_symbol_struct *symbols;   /* Symtab for input bfd.  */
  58   unsigned int *conversion_table;
  59   int conv_table_size;
  60   file_ptr sym_filepos;
  61
  62   struct coff_ptr_struct *raw_syments;
  63   unsigned long raw_syment_count;
  64
  65   /* These are only valid once writing has begun.  */
  66   unsigned long int relocbase;
  67
  68   /* These members communicate important constants about the symbol table
  69      to GDB's symbol-reading code.  These `constants' unfortunately vary
  70      from coff implementation to implementation...  */
  71   unsigned local_n_btmask;
  72   unsigned local_n_btshft;
  73   unsigned local_n_tmask;
  74   unsigned local_n_tshift;
  75   unsigned local_symesz;
  76   unsigned local_auxesz;
  77   unsigned local_linesz;
  78
  79   /* The unswapped external symbols.  May be NULL.  Read by
  80      _bfd_coff_get_external_symbols.  */
  81   void * external_syms;
  82   /* If this is TRUE, the external_syms may not be freed.  */
  83   bool keep_syms;
  84
  85   /* The string table.  May be NULL.  Read by
  86      _bfd_coff_read_string_table.  */
  87   char *strings;
  88   /* The length of the strings table.  For error checking.  */
  89   bfd_size_type strings_len;
  90   /* If this is TRUE, the strings may not be freed.  */
  91   bool keep_strings;
  92   /* If this is TRUE, the strings have been written out already.  */
  93   bool strings_written;
  94
  95   /* Is this a PE format coff file?  */
  96   int pe;
  97   /* Used by the COFF backend linker.  */
  98   struct coff_link_hash_entry **sym_hashes;
  99
 100   /* Used by the pe linker for PowerPC.  */
 101   int *local_toc_sym_map;
 102
 103   struct bfd_link_info *link_info;
 104
 105   /* Used by coff_find_nearest_line.  */
 106   void * line_info;
 107
 108   /* A place to stash dwarf2 info for this bfd.  */
 109   void * dwarf2_find_line_info;
 110
 111   /* The timestamp from the COFF file header.  */
 112   long timestamp;
 113
 114   /* Copy of some of the f_flags bits in the COFF filehdr structure,
 115      used by ARM code.  */
 116   flagword flags;
 117
 118   /* Is this a GO32 coff file?  */
 119   bool go32;
 120
 121   /* A stub (extra data prepended before the COFF image) and its size.
 122      Used by coff-go32-exe, it contains executable data that loads the
 123      COFF object into memory.  */
 124   char * stub;
 125   bfd_size_type stub_size;
 126 } coff_data_type;
 127
 128 /* Tdata for pe image files.  */
 129 typedef struct pe_tdata
 130 {
 131   coff_data_type coff;
 132   struct internal_extra_pe_aouthdr pe_opthdr;
 133   int dll;
 134   int has_reloc_section;
 135   int dont_strip_reloc;
 136   int dos_message[16];
 137   /* The timestamp to insert into the output file.
 138      If the timestamp is -1 then the current time is used.  */
 139   int timestamp;
 140   bool (*in_reloc_p) (bfd *, reloc_howto_type *);
 141   flagword real_flags;
 142
 143   /* Build-id info.  */
 144   struct
 145   {
 146     bool (*after_write_object_contents) (bfd *);
 147     const char *style;
 148     asection *sec;
 149   } build_id;
 150 } pe_data_type;
 151
 152 #define pe_data(bfd)            ((bfd)->tdata.pe_obj_data)
 153
 154 /* Tdata for XCOFF files.  */
 155
 156 struct xcoff_tdata
 157 {
 158   /* Basic COFF information.  */
 159   coff_data_type coff;
 160
 161   /* TRUE if this is an XCOFF64 file. */
 162   bool xcoff64;
 163
 164   /* TRUE if a large a.out header should be generated.  */
 165   bool full_aouthdr;
 166
 167   /* TOC value.  */
 168   bfd_vma toc;
 169
 170   /* Index of section holding TOC.  */
 171   int sntoc;
 172
 173   /* Index of section holding entry point.  */
 174   int snentry;
 175
 176   /* .text alignment from optional header.  */
 177   int text_align_power;
 178
 179   /* .data alignment from optional header.  */
 180   int data_align_power;
 181
 182   /* modtype from optional header.  */
 183   short modtype;
 184
 185   /* cputype from optional header.  */
 186   short cputype;
 187
 188   /* maxdata from optional header.  */
 189   bfd_vma maxdata;
 190
 191   /* maxstack from optional header.  */
 192   bfd_vma maxstack;
 193
 194   /* Used by the XCOFF backend linker.  */
 195   asection **csects;
 196   long *debug_indices;
 197   unsigned int *lineno_counts;
 198   unsigned int import_file_id;
 199 };
 200
 201 #define xcoff_data(abfd) ((abfd)->tdata.xcoff_obj_data)
 202
 203 /* We take the address of the first element of an asymbol to ensure that the
 204    macro is only ever applied to an asymbol.  */
 205 #define coffsymbol(asymbol) ((coff_symbol_type *)(&((asymbol)->the_bfd)))
 206
 207 /* Tdata for sections in XCOFF files.  This is used by the linker.  */
 208
 209 struct xcoff_section_tdata
 210 {
 211   /* Used for XCOFF csects created by the linker; points to the real
 212      XCOFF section which contains this csect.  */
 213   asection *enclosing;
 214   /* The lineno_count field for the enclosing section, because we are
 215      going to clobber it there.  */
 216   unsigned int lineno_count;
 217   /* The first and last symbol indices for symbols used by this csect.  */
 218   unsigned long first_symndx;
 219   unsigned long last_symndx;
 220 };
 221
 222 /* An accessor macro the xcoff_section_tdata structure.  */
 223 #define xcoff_section_data(abfd, sec) \
 224   ((struct xcoff_section_tdata *) coff_section_data ((abfd), (sec))->tdata)
 225
 226 /* Tdata for sections in PE files.  */
 227
 228 struct pei_section_tdata
 229 {
 230   /* The virtual size of the section.  */
 231   bfd_size_type virt_size;
 232   /* The PE section flags.  */
 233   long pe_flags;
 234 };
 235
 236 /* An accessor macro for the pei_section_tdata structure.  */
 237 #define pei_section_data(abfd, sec) \
 238   ((struct pei_section_tdata *) coff_section_data ((abfd), (sec))->tdata)
 239
 240 /* COFF linker hash table entries.  */
 241
 242 struct coff_link_hash_entry
 243 {
 244   struct bfd_link_hash_entry root;
 245
 246   /* Symbol index in output file.  This is initialized to -1.  It is
 247      set to -2 if the symbol is used by a reloc.  It is set to -3 if
 248      this symbol is defined in a discarded section.  */
 249   long indx;
 250
 251   /* Symbol type.  */
 252   unsigned short type;
 253
 254   /* Symbol class.  */
 255   unsigned char symbol_class;
 256
 257   /* Number of auxiliary entries.  */
 258   char numaux;
 259
 260   /* BFD to take auxiliary entries from.  */
 261   bfd *auxbfd;
 262
 263   /* Pointer to array of auxiliary entries, if any.  */
 264   union internal_auxent *aux;
 265
 266   /* Flag word; legal values follow.  */
 267   unsigned short coff_link_hash_flags;
 268   /* Symbol is a PE section symbol.  */
 269 #define COFF_LINK_HASH_PE_SECTION_SYMBOL (01)
 270 };
 271
 272 /* COFF linker hash table.  */
 273
 274 struct coff_link_hash_table
 275 {
 276   struct bfd_link_hash_table root;
 277   /* A pointer to information used to link stabs in sections.  */
 278   struct stab_info stab_info;
 279 };
 280
 281 struct coff_reloc_cookie
 282 {
 283   struct internal_reloc *         rels;
 284   struct internal_reloc *         rel;
 285   struct internal_reloc *         relend;
 286   struct coff_symbol_struct *     symbols;      /* Symtab for input bfd.  */
 287   bfd *                           abfd;
 288   struct coff_link_hash_entry **  sym_hashes;
 289 };
 290
 291 /* Look up an entry in a COFF linker hash table.  */
 292
 293 #define coff_link_hash_lookup(table, string, create, copy, follow)      \
 294   ((struct coff_link_hash_entry *)                                      \
 295    bfd_link_hash_lookup (&(table)->root, (string), (create),            \
 296                          (copy), (follow)))
 297
 298 /* Traverse a COFF linker hash table.  */
 299
 300 #define coff_link_hash_traverse(table, func, info)                      \
 301   (bfd_link_hash_traverse                                               \
 302    (&(table)->root,                                                     \
 303     (bool (*) (struct bfd_link_hash_entry *, void *)) (func),           \
 304     (info)))
 305
 306 /* Get the COFF linker hash table from a link_info structure.  */
 307
 308 #define coff_hash_table(p) ((struct coff_link_hash_table *) ((p)->hash))
 309
 310 /* Functions in coffgen.c.  */
 311 extern bfd_cleanup coff_object_p
 312   (bfd *);
 313 extern struct bfd_section *coff_section_from_bfd_index
 314   (bfd *, int);
 315 extern long coff_get_symtab_upper_bound
 316   (bfd *);
 317 extern long coff_canonicalize_symtab
 318   (bfd *, asymbol **);
 319 extern int coff_count_linenumbers
 320   (bfd *);
 321 extern bool coff_renumber_symbols
 322   (bfd *, int *);
 323 extern void coff_mangle_symbols
 324   (bfd *);
 325 extern bool coff_write_symbols
 326   (bfd *);
 327 extern bool coff_write_alien_symbol
 328   (bfd *, asymbol *, struct internal_syment *, union internal_auxent *,
 329    bfd_vma *, bfd_size_type *, asection **, bfd_size_type *);
 330 extern bool coff_write_linenumbers
 331   (bfd *);
 332 extern alent *coff_get_lineno
 333   (bfd *, asymbol *);
 334 extern asymbol *coff_section_symbol
 335   (bfd *, char *);
 336 extern bool _bfd_coff_get_external_symbols
 337   (bfd *);
 338 extern const char *_bfd_coff_read_string_table
 339   (bfd *);
 340 extern bool _bfd_coff_free_symbols
 341   (bfd *);
 342 extern struct coff_ptr_struct *coff_get_normalized_symtab
 343   (bfd *);
 344 extern long coff_get_reloc_upper_bound
 345   (bfd *, sec_ptr);
 346 extern asymbol *coff_make_empty_symbol
 347   (bfd *);
 348 extern void coff_print_symbol
 349   (bfd *, void * filep, asymbol *, bfd_print_symbol_type);
 350 extern void coff_get_symbol_info
 351   (bfd *, asymbol *, symbol_info *ret);
 352 #define coff_get_symbol_version_string \
 353   _bfd_nosymbols_get_symbol_version_string
 354 extern bool _bfd_coff_is_local_label_name
 355   (bfd *, const char *);
 356 extern asymbol *coff_bfd_make_debug_symbol
 357   (bfd *, void *, unsigned long);
 358 extern bool coff_find_nearest_line
 359   (bfd *, asymbol **, asection *, bfd_vma,
 360    const char **, const char **, unsigned int *, unsigned int *);
 361 #define coff_find_line _bfd_nosymbols_find_line
 362 struct dwarf_debug_section;
 363 extern bool coff_find_nearest_line_with_names
 364   (bfd *, asymbol **, asection *, bfd_vma, const char **, const char **,
 365    unsigned int *, const struct dwarf_debug_section *);
 366 extern bool coff_find_inliner_info
 367   (bfd *, const char **, const char **, unsigned int *);
 368 extern int coff_sizeof_headers
 369   (bfd *, struct bfd_link_info *);
 370 extern bool bfd_coff_reloc16_relax_section
 371   (bfd *, asection *, struct bfd_link_info *, bool *);
 372 extern bfd_byte *bfd_coff_reloc16_get_relocated_section_contents
 373   (bfd *, struct bfd_link_info *, struct bfd_link_order *,
 374    bfd_byte *, bool, asymbol **);
 375 extern bfd_vma bfd_coff_reloc16_get_value
 376   (arelent *, struct bfd_link_info *, asection *);
 377 extern void bfd_perform_slip
 378   (bfd *, unsigned int, asection *, bfd_vma);
 379 extern bool _bfd_coff_close_and_cleanup
 380   (bfd *);
 381
 382 /* Functions and types in cofflink.c.  */
 383
 384 #define STRING_SIZE_SIZE 4
 385
 386 /* We use a hash table to merge identical enum, struct, and union
 387    definitions in the linker.  */
 388
 389 /* Information we keep for a single element (an enum value, a
 390    structure or union field) in the debug merge hash table.  */
 391
 392 struct coff_debug_merge_element
 393 {
 394   /* Next element.  */
 395   struct coff_debug_merge_element *next;
 396
 397   /* Name.  */
 398   const char *name;
 399
 400   /* Type.  */
 401   unsigned int type;
 402
 403   /* Symbol index for complex type.  */
 404   long tagndx;
 405 };
 406
 407 /* A linked list of debug merge entries for a given name.  */
 408
 409 struct coff_debug_merge_type
 410 {
 411   /* Next type with the same name.  */
 412   struct coff_debug_merge_type *next;
 413
 414   /* Class of type.  */
 415   int type_class;
 416
 417   /* Symbol index where this type is defined.  */
 418   long indx;
 419
 420   /* List of elements.  */
 421   struct coff_debug_merge_element *elements;
 422 };
 423
 424 /* Information we store in the debug merge hash table.  */
 425
 426 struct coff_debug_merge_hash_entry
 427 {
 428   struct bfd_hash_entry root;
 429
 430   /* A list of types with this name.  */
 431   struct coff_debug_merge_type *types;
 432 };
 433
 434 /* The debug merge hash table.  */
 435
 436 struct coff_debug_merge_hash_table
 437 {
 438   struct bfd_hash_table root;
 439 };
 440
 441 /* Initialize a COFF debug merge hash table.  */
 442
 443 #define coff_debug_merge_hash_table_init(table) \
 444   (bfd_hash_table_init (&(table)->root, _bfd_coff_debug_merge_hash_newfunc, \
 445                         sizeof (struct coff_debug_merge_hash_entry)))
 446
 447 /* Free a COFF debug merge hash table.  */
 448
 449 #define coff_debug_merge_hash_table_free(table) \
 450   (bfd_hash_table_free (&(table)->root))
 451
 452 /* Look up an entry in a COFF debug merge hash table.  */
 453
 454 #define coff_debug_merge_hash_lookup(table, string, create, copy) \
 455   ((struct coff_debug_merge_hash_entry *) \
 456    bfd_hash_lookup (&(table)->root, (string), (create), (copy)))
 457
 458 /* Information we keep for each section in the output file when doing
 459    a relocatable link.  */
 460
 461 struct coff_link_section_info
 462 {
 463   /* The relocs to be output.  */
 464   struct internal_reloc *relocs;
 465   /* For each reloc against a global symbol whose index was not known
 466      when the reloc was handled, the global hash table entry.  */
 467   struct coff_link_hash_entry **rel_hashes;
 468 };
 469
 470 /* Information that we pass around while doing the final link step.  */
 471
 472 struct coff_final_link_info
 473 {
 474   /* General link information.  */
 475   struct bfd_link_info *info;
 476   /* Output BFD.  */
 477   bfd *output_bfd;
 478   /* Used to indicate failure in traversal routine.  */
 479   bool failed;
 480   /* If doing "task linking" set only during the time when we want the
 481      global symbol writer to convert the storage class of defined global
 482      symbols from global to static. */
 483   bool global_to_static;
 484   /* Hash table for long symbol names.  */
 485   struct bfd_strtab_hash *strtab;
 486   /* When doing a relocatable link, an array of information kept for
 487      each output section, indexed by the target_index field.  */
 488   struct coff_link_section_info *section_info;
 489   /* Symbol index of last C_FILE symbol (-1 if none).  */
 490   long last_file_index;
 491   /* Contents of last C_FILE symbol.  */
 492   struct internal_syment last_file;
 493   /* Symbol index of first aux entry of last .bf symbol with an empty
 494      endndx field (-1 if none).  */
 495   long last_bf_index;
 496   /* Contents of last_bf_index aux entry.  */
 497   union internal_auxent last_bf;
 498   /* Hash table used to merge debug information.  */
 499   struct coff_debug_merge_hash_table debug_merge;
 500   /* Buffer large enough to hold swapped symbols of any input file.  */
 501   struct internal_syment *internal_syms;
 502   /* Buffer large enough to hold sections of symbols of any input file.  */
 503   asection **sec_ptrs;
 504   /* Buffer large enough to hold output indices of symbols of any
 505      input file.  */
 506   long *sym_indices;
 507   /* Buffer large enough to hold output symbols for any input file.  */
 508   bfd_byte *outsyms;
 509   /* Buffer large enough to hold external line numbers for any input
 510      section.  */
 511   bfd_byte *linenos;
 512   /* Buffer large enough to hold any input section.  */
 513   bfd_byte *contents;
 514   /* Buffer large enough to hold external relocs of any input section.  */
 515   bfd_byte *external_relocs;
 516   /* Buffer large enough to hold swapped relocs of any input section.  */
 517   struct internal_reloc *internal_relocs;
 518 };
 519
 520 /* Most COFF variants have no way to record the alignment of a
 521    section.  This struct is used to set a specific alignment based on
 522    the name of the section.  */
 523
 524 struct coff_section_alignment_entry
 525 {
 526   /* The section name.  */
 527   const char *name;
 528
 529   /* This is either (unsigned int) -1, indicating that the section
 530      name must match exactly, or it is the number of letters which
 531      must match at the start of the name.  */
 532   unsigned int comparison_length;
 533
 534   /* These macros may be used to fill in the first two fields in a
 535      structure initialization.  */
 536 #define COFF_SECTION_NAME_EXACT_MATCH(name) (name), ((unsigned int) -1)
 537 #define COFF_SECTION_NAME_PARTIAL_MATCH(name) (name), (sizeof (name) - 1)
 538
 539   /* Only use this entry if the default section alignment for this
 540      target is at least that much (as a power of two).  If this field
 541      is COFF_ALIGNMENT_FIELD_EMPTY, it should be ignored.  */
 542   unsigned int default_alignment_min;
 543
 544   /* Only use this entry if the default section alignment for this
 545      target is no greater than this (as a power of two).  If this
 546      field is COFF_ALIGNMENT_FIELD_EMPTY, it should be ignored.  */
 547   unsigned int default_alignment_max;
 548
 549 #define COFF_ALIGNMENT_FIELD_EMPTY ((unsigned int) -1)
 550
 551   /* The desired alignment for this section (as a power of two).  */
 552   unsigned int alignment_power;
 553 };
 554
 555 extern struct bfd_hash_entry *_bfd_coff_link_hash_newfunc
 556   (struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
 557 extern bool _bfd_coff_link_hash_table_init
 558   (struct coff_link_hash_table *, bfd *,
 559    struct bfd_hash_entry *(*) (struct bfd_hash_entry *,
 560                                struct bfd_hash_table *,
 561                                const char *),
 562    unsigned int);
 563 extern struct bfd_link_hash_table *_bfd_coff_link_hash_table_create
 564   (bfd *);
 565 extern const char *_bfd_coff_internal_syment_name
 566   (bfd *, const struct internal_syment *, char *);
 567 extern bool _bfd_coff_section_already_linked
 568   (bfd *, asection *, struct bfd_link_info *);
 569 extern bool _bfd_coff_link_add_symbols
 570   (bfd *, struct bfd_link_info *);
 571 extern bool _bfd_coff_final_link
 572   (bfd *, struct bfd_link_info *);
 573 extern struct internal_reloc *_bfd_coff_read_internal_relocs
 574   (bfd *, asection *, bool, bfd_byte *, bool,
 575    struct internal_reloc *);
 576 extern bool _bfd_coff_generic_relocate_section
 577   (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
 578    struct internal_reloc *, struct internal_syment *, asection **);
 579 extern struct bfd_hash_entry *_bfd_coff_debug_merge_hash_newfunc
 580   (struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
 581 extern bool _bfd_coff_write_global_sym
 582   (struct bfd_hash_entry *, void *);
 583 extern bool _bfd_coff_write_task_globals
 584   (struct coff_link_hash_entry *, void *);
 585 extern bool _bfd_coff_link_input_bfd
 586   (struct coff_final_link_info *, bfd *);
 587 extern bool _bfd_coff_reloc_link_order
 588   (bfd *, struct coff_final_link_info *, asection *,
 589    struct bfd_link_order *);
 590 extern bool bfd_coff_gc_sections
 591   (bfd *, struct bfd_link_info *);
 592 extern const char *bfd_coff_group_name
 593   (bfd *, const asection *);
 594
 595 #define coff_get_section_contents_in_window \
 596   _bfd_generic_get_section_contents_in_window
 597
 598 /* Functions in xcofflink.c.  */
 599
 600 extern long _bfd_xcoff_get_dynamic_symtab_upper_bound
 601   (bfd *);
 602 extern long _bfd_xcoff_canonicalize_dynamic_symtab
 603   (bfd *, asymbol **);
 604 extern long _bfd_xcoff_get_dynamic_reloc_upper_bound
 605   (bfd *);
 606 extern long _bfd_xcoff_canonicalize_dynamic_reloc
 607   (bfd *, arelent **, asymbol **);
 608 extern struct bfd_link_hash_table *_bfd_xcoff_bfd_link_hash_table_create
 609   (bfd *);
 610 extern bool _bfd_xcoff_bfd_link_add_symbols
 611   (bfd *, struct bfd_link_info *);
 612 extern bool _bfd_xcoff_bfd_final_link
 613   (bfd *, struct bfd_link_info *);
 614 extern bool _bfd_xcoff_define_common_symbol
 615   (bfd *, struct bfd_link_info *, struct bfd_link_hash_entry *);
 616 extern bool _bfd_ppc_xcoff_relocate_section
 617   (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
 618    struct internal_reloc *, struct internal_syment *, asection **);