| /* bfdlink.h -- header file for BFD link routines |
| Copyright (C) 1993-2021 Free Software Foundation, Inc. |
| Written by Steve Chamberlain and Ian Lance Taylor, Cygnus Support. |
| |
| This file is part of BFD, the Binary File Descriptor library. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
| MA 02110-1301, USA. */ |
| |
| #ifndef BFDLINK_H |
| #define BFDLINK_H |
| |
| /* Which symbols to strip during a link. */ |
| enum bfd_link_strip |
| { |
| strip_none, /* Don't strip any symbols. */ |
| strip_debugger, /* Strip debugging symbols. */ |
| strip_some, /* keep_hash is the list of symbols to keep. */ |
| strip_all /* Strip all symbols. */ |
| }; |
| |
| /* Which local symbols to discard during a link. This is irrelevant |
| if strip_all is used. */ |
| enum bfd_link_discard |
| { |
| discard_sec_merge, /* Discard local temporary symbols in SEC_MERGE |
| sections. */ |
| discard_none, /* Don't discard any locals. */ |
| discard_l, /* Discard local temporary symbols. */ |
| discard_all /* Discard all locals. */ |
| }; |
| |
| enum notice_asneeded_action { |
| notice_as_needed, |
| notice_not_needed, |
| notice_needed |
| }; |
| |
| /* Whether to generate ELF common symbols with the STT_COMMON type |
| during a relocatable link. */ |
| enum bfd_link_elf_stt_common |
| { |
| unchanged, |
| elf_stt_common, |
| no_elf_stt_common |
| }; |
| |
| /* Describes the type of hash table entry structure being used. |
| Different hash table structure have different fields and so |
| support different linking features. */ |
| enum bfd_link_hash_table_type |
| { |
| bfd_link_generic_hash_table, |
| bfd_link_elf_hash_table |
| }; |
| |
| /* These are the possible types of an entry in the BFD link hash |
| table. */ |
| |
| enum bfd_link_hash_type |
| { |
| bfd_link_hash_new, /* Symbol is new. */ |
| bfd_link_hash_undefined, /* Symbol seen before, but undefined. */ |
| bfd_link_hash_undefweak, /* Symbol is weak and undefined. */ |
| bfd_link_hash_defined, /* Symbol is defined. */ |
| bfd_link_hash_defweak, /* Symbol is weak and defined. */ |
| bfd_link_hash_common, /* Symbol is common. */ |
| bfd_link_hash_indirect, /* Symbol is an indirect link. */ |
| bfd_link_hash_warning /* Like indirect, but warn if referenced. */ |
| }; |
| |
| enum bfd_link_common_skip_ar_symbols |
| { |
| bfd_link_common_skip_none, |
| bfd_link_common_skip_text, |
| bfd_link_common_skip_data, |
| bfd_link_common_skip_all |
| }; |
| |
| struct bfd_link_hash_common_entry |
| { |
| unsigned int alignment_power; /* Alignment. */ |
| asection *section; /* Symbol section. */ |
| }; |
| |
| /* The linking routines use a hash table which uses this structure for |
| its elements. */ |
| |
| struct bfd_link_hash_entry |
| { |
| /* Base hash table entry structure. */ |
| struct bfd_hash_entry root; |
| |
| /* Type of this entry. */ |
| ENUM_BITFIELD (bfd_link_hash_type) type : 8; |
| |
| /* Symbol is referenced in a normal regular object file, |
| as distinct from a LTO IR object file. */ |
| unsigned int non_ir_ref_regular : 1; |
| |
| /* Symbol is referenced in a normal dynamic object file, |
| as distinct from a LTO IR object file. */ |
| unsigned int non_ir_ref_dynamic : 1; |
| |
| /* Symbol is a built-in define. These will be overridden by PROVIDE |
| in a linker script. */ |
| unsigned int linker_def : 1; |
| |
| /* Symbol defined in a linker script. */ |
| unsigned int ldscript_def : 1; |
| |
| /* Symbol will be converted from absolute to section-relative. Set for |
| symbols defined by a script from "dot" (also SEGMENT_START or ORIGIN) |
| outside of an output section statement. */ |
| unsigned int rel_from_abs : 1; |
| |
| /* A union of information depending upon the type. */ |
| union |
| { |
| /* Nothing is kept for bfd_hash_new. */ |
| /* bfd_link_hash_undefined, bfd_link_hash_undefweak. */ |
| struct |
| { |
| /* Undefined and common symbols are kept in a linked list through |
| this field. This field is present in all of the union element |
| so that we don't need to remove entries from the list when we |
| change their type. Removing entries would either require the |
| list to be doubly linked, which would waste more memory, or |
| require a traversal. When an undefined or common symbol is |
| created, it should be added to this list, the head of which is in |
| the link hash table itself. As symbols are defined, they need |
| not be removed from the list; anything which reads the list must |
| doublecheck the symbol type. |
| |
| Weak symbols are not kept on this list. |
| |
| Defined and defweak symbols use this field as a reference marker. |
| If the field is not NULL, or this structure is the tail of the |
| undefined symbol list, the symbol has been referenced. If the |
| symbol is undefined and becomes defined, this field will |
| automatically be non-NULL since the symbol will have been on the |
| undefined symbol list. */ |
| struct bfd_link_hash_entry *next; |
| /* BFD symbol was found in. */ |
| bfd *abfd; |
| } undef; |
| /* bfd_link_hash_defined, bfd_link_hash_defweak. */ |
| struct |
| { |
| struct bfd_link_hash_entry *next; |
| /* Symbol section. */ |
| asection *section; |
| /* Symbol value. */ |
| bfd_vma value; |
| } def; |
| /* bfd_link_hash_indirect, bfd_link_hash_warning. */ |
| struct |
| { |
| struct bfd_link_hash_entry *next; |
| /* Real symbol. */ |
| struct bfd_link_hash_entry *link; |
| /* Warning message (bfd_link_hash_warning only). */ |
| const char *warning; |
| } i; |
| /* bfd_link_hash_common. */ |
| struct |
| { |
| struct bfd_link_hash_entry *next; |
| /* The linker needs to know three things about common |
| symbols: the size, the alignment, and the section in |
| which the symbol should be placed. We store the size |
| here, and we allocate a small structure to hold the |
| section and the alignment. The alignment is stored as a |
| power of two. We don't store all the information |
| directly because we don't want to increase the size of |
| the union; this structure is a major space user in the |
| linker. */ |
| struct bfd_link_hash_common_entry *p; |
| /* Common symbol size. */ |
| bfd_size_type size; |
| } c; |
| } u; |
| }; |
| |
| /* This is the link hash table. It is a derived class of |
| bfd_hash_table. */ |
| |
| struct bfd_link_hash_table |
| { |
| /* The hash table itself. */ |
| struct bfd_hash_table table; |
| /* A linked list of undefined and common symbols, linked through the |
| next field in the bfd_link_hash_entry structure. */ |
| struct bfd_link_hash_entry *undefs; |
| /* Entries are added to the tail of the undefs list. */ |
| struct bfd_link_hash_entry *undefs_tail; |
| /* Function to free the hash table on closing BFD. */ |
| void (*hash_table_free) (bfd *); |
| /* The type of the link hash table. */ |
| enum bfd_link_hash_table_type type; |
| }; |
| |
| /* Look up an entry in a link hash table. If FOLLOW is TRUE, this |
| follows bfd_link_hash_indirect and bfd_link_hash_warning links to |
| the real symbol. */ |
| extern struct bfd_link_hash_entry *bfd_link_hash_lookup |
| (struct bfd_link_hash_table *, const char *, bool create, |
| bool copy, bool follow); |
| |
| /* Look up an entry in the main linker hash table if the symbol might |
| be wrapped. This should only be used for references to an |
| undefined symbol, not for definitions of a symbol. */ |
| |
| extern struct bfd_link_hash_entry *bfd_wrapped_link_hash_lookup |
| (bfd *, struct bfd_link_info *, const char *, bool, bool, bool); |
| |
| /* If H is a wrapped symbol, ie. the symbol name starts with "__wrap_" |
| and the remainder is found in wrap_hash, return the real symbol. */ |
| |
| extern struct bfd_link_hash_entry *unwrap_hash_lookup |
| (struct bfd_link_info *, bfd *, struct bfd_link_hash_entry *); |
| |
| /* Traverse a link hash table. */ |
| extern void bfd_link_hash_traverse |
| (struct bfd_link_hash_table *, |
| bool (*) (struct bfd_link_hash_entry *, void *), |
| void *); |
| |
| /* Add an entry to the undefs list. */ |
| extern void bfd_link_add_undef |
| (struct bfd_link_hash_table *, struct bfd_link_hash_entry *); |
| |
| /* Remove symbols from the undefs list that don't belong there. */ |
| extern void bfd_link_repair_undef_list |
| (struct bfd_link_hash_table *table); |
| |
| /* Read symbols and cache symbol pointer array in outsymbols. */ |
| extern bool bfd_generic_link_read_symbols (bfd *); |
| |
| /* Check the relocs in the BFD. Called after all the input |
| files have been loaded, and garbage collection has tagged |
| any unneeded sections. */ |
| extern bool bfd_link_check_relocs (bfd *,struct bfd_link_info *); |
| |
| struct bfd_sym_chain |
| { |
| struct bfd_sym_chain *next; |
| const char *name; |
| }; |
| |
| /* How to handle unresolved symbols. |
| There are four possibilities which are enumerated below: */ |
| enum report_method |
| { |
| /* This is the initial value when then link_info structure is created. |
| It allows the various stages of the linker to determine whether they |
| allowed to set the value. */ |
| RM_NOT_YET_SET = 0, |
| RM_IGNORE, |
| RM_DIAGNOSE, |
| }; |
| |
| /* How to handle DT_TEXTREL. */ |
| |
| enum textrel_check_method |
| { |
| textrel_check_none, |
| textrel_check_warning, |
| textrel_check_error |
| }; |
| |
| #define bfd_link_textrel_check(info) \ |
| (info->textrel_check != textrel_check_none) |
| |
| typedef enum {with_flags, without_flags} flag_type; |
| |
| /* A section flag list. */ |
| struct flag_info_list |
| { |
| flag_type with; |
| const char *name; |
| bool valid; |
| struct flag_info_list *next; |
| }; |
| |
| /* Section flag info. */ |
| struct flag_info |
| { |
| flagword only_with_flags; |
| flagword not_with_flags; |
| struct flag_info_list *flag_list; |
| bool flags_initialized; |
| }; |
| |
| struct bfd_elf_dynamic_list; |
| struct bfd_elf_version_tree; |
| |
| /* Types of output. */ |
| |
| enum output_type |
| { |
| type_pde, |
| type_pie, |
| type_relocatable, |
| type_dll, |
| }; |
| |
| #define bfd_link_pde(info) ((info)->type == type_pde) |
| #define bfd_link_dll(info) ((info)->type == type_dll) |
| #define bfd_link_relocatable(info) ((info)->type == type_relocatable) |
| #define bfd_link_pie(info) ((info)->type == type_pie) |
| #define bfd_link_executable(info) (bfd_link_pde (info) || bfd_link_pie (info)) |
| #define bfd_link_pic(info) (bfd_link_dll (info) || bfd_link_pie (info)) |
| |
| /* This structure holds all the information needed to communicate |
| between BFD and the linker when doing a link. */ |
| |
| struct bfd_link_info |
| { |
| /* Output type. */ |
| ENUM_BITFIELD (output_type) type : 2; |
| |
| /* TRUE if BFD should pre-bind symbols in a shared object. */ |
| unsigned int symbolic: 1; |
| |
| /* TRUE if BFD should export all symbols in the dynamic symbol table |
| of an executable, rather than only those used. */ |
| unsigned int export_dynamic: 1; |
| |
| /* TRUE if a default symbol version should be created and used for |
| exported symbols. */ |
| unsigned int create_default_symver: 1; |
| |
| /* TRUE if unreferenced sections should be removed. */ |
| unsigned int gc_sections: 1; |
| |
| /* TRUE if exported symbols should be kept during section gc. */ |
| unsigned int gc_keep_exported: 1; |
| |
| /* TRUE if every symbol should be reported back via the notice |
| callback. */ |
| unsigned int notice_all: 1; |
| |
| /* TRUE if the LTO plugin is active. */ |
| unsigned int lto_plugin_active: 1; |
| |
| /* TRUE if all LTO IR symbols have been read. */ |
| unsigned int lto_all_symbols_read : 1; |
| |
| /* TRUE if global symbols in discarded sections should be stripped. */ |
| unsigned int strip_discarded: 1; |
| |
| /* TRUE if all data symbols should be dynamic. */ |
| unsigned int dynamic_data: 1; |
| |
| /* TRUE if section groups should be resolved. */ |
| unsigned int resolve_section_groups: 1; |
| |
| /* Set if output file is big-endian, or if that is unknown, from |
| the command line or first input file endianness. */ |
| unsigned int big_endian : 1; |
| |
| /* Which symbols to strip. */ |
| ENUM_BITFIELD (bfd_link_strip) strip : 2; |
| |
| /* Which local symbols to discard. */ |
| ENUM_BITFIELD (bfd_link_discard) discard : 2; |
| |
| /* Whether to generate ELF common symbols with the STT_COMMON type. */ |
| ENUM_BITFIELD (bfd_link_elf_stt_common) elf_stt_common : 2; |
| |
| /* Criteria for skipping symbols when determining |
| whether to include an object from an archive. */ |
| ENUM_BITFIELD (bfd_link_common_skip_ar_symbols) common_skip_ar_symbols : 2; |
| |
| /* What to do with unresolved symbols in an object file. |
| When producing executables the default is GENERATE_ERROR. |
| When producing shared libraries the default is IGNORE. The |
| assumption with shared libraries is that the reference will be |
| resolved at load/execution time. */ |
| ENUM_BITFIELD (report_method) unresolved_syms_in_objects : 2; |
| |
| /* What to do with unresolved symbols in a shared library. |
| The same defaults apply. */ |
| ENUM_BITFIELD (report_method) unresolved_syms_in_shared_libs : 2; |
| |
| /* TRUE if unresolved symbols are to be warned, rather than errored. */ |
| unsigned int warn_unresolved_syms: 1; |
| |
| /* TRUE if shared objects should be linked directly, not shared. */ |
| unsigned int static_link: 1; |
| |
| /* TRUE if symbols should be retained in memory, FALSE if they |
| should be freed and reread. */ |
| unsigned int keep_memory: 1; |
| |
| /* TRUE if BFD should generate relocation information in the final |
| executable. */ |
| unsigned int emitrelocations: 1; |
| |
| /* TRUE if PT_GNU_RELRO segment should be created. */ |
| unsigned int relro: 1; |
| |
| /* TRUE if separate code segment should be created. */ |
| unsigned int separate_code: 1; |
| |
| /* Nonzero if .eh_frame_hdr section and PT_GNU_EH_FRAME ELF segment |
| should be created. 1 for DWARF2 tables, 2 for compact tables. */ |
| unsigned int eh_frame_hdr_type: 2; |
| |
| /* What to do with DT_TEXTREL in output. */ |
| ENUM_BITFIELD (textrel_check_method) textrel_check: 2; |
| |
| /* TRUE if .hash section should be created. */ |
| unsigned int emit_hash: 1; |
| |
| /* TRUE if .gnu.hash section should be created. */ |
| unsigned int emit_gnu_hash: 1; |
| |
| /* If TRUE reduce memory overheads, at the expense of speed. This will |
| cause map file generation to use an O(N^2) algorithm and disable |
| caching ELF symbol buffer. */ |
| unsigned int reduce_memory_overheads: 1; |
| |
| /* TRUE if the output file should be in a traditional format. This |
| is equivalent to the setting of the BFD_TRADITIONAL_FORMAT flag |
| on the output file, but may be checked when reading the input |
| files. */ |
| unsigned int traditional_format: 1; |
| |
| /* TRUE if non-PLT relocs should be merged into one reloc section |
| and sorted so that relocs against the same symbol come together. */ |
| unsigned int combreloc: 1; |
| |
| /* TRUE if a default symbol version should be created and used for |
| imported symbols. */ |
| unsigned int default_imported_symver: 1; |
| |
| /* TRUE if the new ELF dynamic tags are enabled. */ |
| unsigned int new_dtags: 1; |
| |
| /* FALSE if .eh_frame unwind info should be generated for PLT and other |
| linker created sections, TRUE if it should be omitted. */ |
| unsigned int no_ld_generated_unwind_info: 1; |
| |
| /* TRUE if BFD should generate a "task linked" object file, |
| similar to relocatable but also with globals converted to |
| statics. */ |
| unsigned int task_link: 1; |
| |
| /* TRUE if ok to have multiple definitions, without warning. */ |
| unsigned int allow_multiple_definition: 1; |
| |
| /* TRUE if multiple definition of absolute symbols (eg. from -R) should |
| be reported. */ |
| unsigned int prohibit_multiple_definition_absolute: 1; |
| |
| /* TRUE if multiple definitions should only warn. */ |
| unsigned int warn_multiple_definition: 1; |
| |
| /* TRUE if ok to have version with no definition. */ |
| unsigned int allow_undefined_version: 1; |
| |
| /* TRUE if some symbols have to be dynamic, controlled by |
| --dynamic-list command line options. */ |
| unsigned int dynamic: 1; |
| |
| /* TRUE if PT_GNU_STACK segment should be created with PF_R|PF_W|PF_X |
| flags. */ |
| unsigned int execstack: 1; |
| |
| /* TRUE if PT_GNU_STACK segment should be created with PF_R|PF_W |
| flags. */ |
| unsigned int noexecstack: 1; |
| |
| /* TRUE if we want to produced optimized output files. This might |
| need much more time and therefore must be explicitly selected. */ |
| unsigned int optimize: 1; |
| |
| /* TRUE if user should be informed of removed unreferenced sections. */ |
| unsigned int print_gc_sections: 1; |
| |
| /* TRUE if we should warn alternate ELF machine code. */ |
| unsigned int warn_alternate_em: 1; |
| |
| /* TRUE if the linker script contained an explicit PHDRS command. */ |
| unsigned int user_phdrs: 1; |
| |
| /* TRUE if program headers ought to be loaded. */ |
| unsigned int load_phdrs: 1; |
| |
| /* TRUE if we should check relocations after all input files have |
| been opened. */ |
| unsigned int check_relocs_after_open_input: 1; |
| |
| /* TRUE if generation of .interp/PT_INTERP should be suppressed. */ |
| unsigned int nointerp: 1; |
| |
| /* TRUE if common symbols should be treated as undefined. */ |
| unsigned int inhibit_common_definition : 1; |
| |
| /* TRUE if "-Map map" is passed to linker. */ |
| unsigned int has_map_file : 1; |
| |
| /* TRUE if "--enable-non-contiguous-regions" is passed to the |
| linker. */ |
| unsigned int non_contiguous_regions : 1; |
| |
| /* TRUE if "--enable-non-contiguous-regions-warnings" is passed to |
| the linker. */ |
| unsigned int non_contiguous_regions_warnings : 1; |
| |
| /* TRUE if all symbol names should be unique. */ |
| unsigned int unique_symbol : 1; |
| |
| /* Char that may appear as the first char of a symbol, but should be |
| skipped (like symbol_leading_char) when looking up symbols in |
| wrap_hash. Used by PowerPC Linux for 'dot' symbols. */ |
| char wrap_char; |
| |
| /* Separator between archive and filename in linker script filespecs. */ |
| char path_separator; |
| |
| /* Compress DWARF debug sections. */ |
| enum compressed_debug_section_type compress_debug; |
| |
| /* Default stack size. Zero means default (often zero itself), -1 |
| means explicitly zero-sized. */ |
| bfd_signed_vma stacksize; |
| |
| /* Enable or disable target specific optimizations. |
| |
| Not all targets have optimizations to enable. |
| |
| Normally these optimizations are disabled by default but some targets |
| prefer to enable them by default. So this field is a tri-state variable. |
| The values are: |
| |
| zero: Enable the optimizations (either from --relax being specified on |
| the command line or the backend's before_allocation emulation function. |
| |
| positive: The user has requested that these optimizations be disabled. |
| (Via the --no-relax command line option). |
| |
| negative: The optimizations are disabled. (Set when initializing the |
| args_type structure in ldmain.c:main. */ |
| signed int disable_target_specific_optimizations; |
| |
| /* Function callbacks. */ |
| const struct bfd_link_callbacks *callbacks; |
| |
| /* Hash table handled by BFD. */ |
| struct bfd_link_hash_table *hash; |
| |
| /* Hash table of symbols to keep. This is NULL unless strip is |
| strip_some. */ |
| struct bfd_hash_table *keep_hash; |
| |
| /* Hash table of symbols to report back via the notice callback. If |
| this is NULL, and notice_all is FALSE, then no symbols are |
| reported back. */ |
| struct bfd_hash_table *notice_hash; |
| |
| /* Hash table of symbols which are being wrapped (the --wrap linker |
| option). If this is NULL, no symbols are being wrapped. */ |
| struct bfd_hash_table *wrap_hash; |
| |
| /* Hash table of symbols which may be left unresolved during |
| a link. If this is NULL, no symbols can be left unresolved. */ |
| struct bfd_hash_table *ignore_hash; |
| |
| /* The output BFD. */ |
| bfd *output_bfd; |
| |
| /* The import library generated. */ |
| bfd *out_implib_bfd; |
| |
| /* The list of input BFD's involved in the link. These are chained |
| together via the link.next field. */ |
| bfd *input_bfds; |
| bfd **input_bfds_tail; |
| |
| /* If a symbol should be created for each input BFD, this is section |
| where those symbols should be placed. It must be a section in |
| the output BFD. It may be NULL, in which case no such symbols |
| will be created. This is to support CREATE_OBJECT_SYMBOLS in the |
| linker command language. */ |
| asection *create_object_symbols_section; |
| |
| /* List of global symbol names that are starting points for marking |
| sections against garbage collection. */ |
| struct bfd_sym_chain *gc_sym_list; |
| |
| /* If a base output file is wanted, then this points to it */ |
| void *base_file; |
| |
| /* The function to call when the executable or shared object is |
| loaded. */ |
| const char *init_function; |
| |
| /* The function to call when the executable or shared object is |
| unloaded. */ |
| const char *fini_function; |
| |
| /* Number of relaxation passes. Usually only one relaxation pass |
| is needed. But a backend can have as many relaxation passes as |
| necessary. During bfd_relax_section call, it is set to the |
| current pass, starting from 0. */ |
| int relax_pass; |
| |
| /* Number of relaxation trips. This number is incremented every |
| time the relaxation pass is restarted due to a previous |
| relaxation returning true in *AGAIN. */ |
| int relax_trip; |
| |
| /* > 0 to treat protected data defined in the shared library as |
| reference external. 0 to treat it as internal. -1 to let |
| backend to decide. */ |
| int extern_protected_data; |
| |
| /* 1 to make undefined weak symbols dynamic when building a dynamic |
| object. 0 to resolve undefined weak symbols to zero. -1 to let |
| the backend decide. */ |
| int dynamic_undefined_weak; |
| |
| /* Non-zero if auto-import thunks for DATA items in pei386 DLLs |
| should be generated/linked against. Set to 1 if this feature |
| is explicitly requested by the user, -1 if enabled by default. */ |
| int pei386_auto_import; |
| |
| /* Non-zero if runtime relocs for DATA items with non-zero addends |
| in pei386 DLLs should be generated. Set to 1 if this feature |
| is explicitly requested by the user, -1 if enabled by default. */ |
| int pei386_runtime_pseudo_reloc; |
| |
| /* How many spare .dynamic DT_NULL entries should be added? */ |
| unsigned int spare_dynamic_tags; |
| |
| /* GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS control: |
| > 1: Turn on by -z indirect-extern-access or by backend. |
| == 1: Turn on by an input. |
| 0: Turn off. |
| < 0: Turn on if it is set on any inputs or let backend to |
| decide. */ |
| int indirect_extern_access; |
| |
| /* Non-zero if executable should not contain copy relocs. |
| > 1: Implied by indirect_extern_access. |
| == 1: Turn on by -z nocopyreloc. |
| 0: Turn off. |
| Setting this to non-zero may result in a non-sharable text |
| segment. */ |
| int nocopyreloc; |
| |
| /* Pointer to the GNU_PROPERTY_1_NEEDED property in memory. */ |
| bfd_byte *needed_1_p; |
| |
| /* May be used to set DT_FLAGS for ELF. */ |
| bfd_vma flags; |
| |
| /* May be used to set DT_FLAGS_1 for ELF. */ |
| bfd_vma flags_1; |
| |
| /* May be used to set DT_GNU_FLAGS_1 for ELF. */ |
| bfd_vma gnu_flags_1; |
| |
| /* TRUE if references to __start_/__stop_ synthesized symbols do not |
| specially retain C identifier named sections. */ |
| int start_stop_gc; |
| |
| /* May be used to set ELF visibility for __start_* / __stop_. */ |
| unsigned int start_stop_visibility; |
| |
| /* The maximum page size for ELF. */ |
| bfd_vma maxpagesize; |
| |
| /* The common page size for ELF. */ |
| bfd_vma commonpagesize; |
| |
| /* Start and end of RELRO region. */ |
| bfd_vma relro_start, relro_end; |
| |
| /* List of symbols should be dynamic. */ |
| struct bfd_elf_dynamic_list *dynamic_list; |
| |
| /* The version information. */ |
| struct bfd_elf_version_tree *version_info; |
| |
| /* Size of cache. Backend can use it to keep strace cache size. */ |
| bfd_size_type cache_size; |
| |
| /* The maximum cache size. Backend can use cache_size and and |
| max_cache_size to decide if keep_memory should be honored. */ |
| bfd_size_type max_cache_size; |
| }; |
| |
| /* Some forward-definitions used by some callbacks. */ |
| |
| struct elf_strtab_hash; |
| struct elf_internal_sym; |
| |
| /* This structures holds a set of callback functions. These are called |
| by the BFD linker routines. */ |
| |
| struct bfd_link_callbacks |
| { |
| /* A function which is called when an object is added from an |
| archive. ABFD is the archive element being added. NAME is the |
| name of the symbol which caused the archive element to be pulled |
| in. This function may set *SUBSBFD to point to an alternative |
| BFD from which symbols should in fact be added in place of the |
| original BFD's symbols. Returns TRUE if the object should be |
| added, FALSE if it should be skipped. */ |
| bool (*add_archive_element) |
| (struct bfd_link_info *, bfd *abfd, const char *name, bfd **subsbfd); |
| /* A function which is called when a symbol is found with multiple |
| definitions. H is the symbol which is defined multiple times. |
| NBFD is the new BFD, NSEC is the new section, and NVAL is the new |
| value. NSEC may be bfd_com_section or bfd_ind_section. */ |
| void (*multiple_definition) |
| (struct bfd_link_info *, struct bfd_link_hash_entry *h, |
| bfd *nbfd, asection *nsec, bfd_vma nval); |
| /* A function which is called when a common symbol is defined |
| multiple times. H is the symbol appearing multiple times. |
| NBFD is the BFD of the new symbol. NTYPE is the type of the new |
| symbol, one of bfd_link_hash_defined, bfd_link_hash_common, or |
| bfd_link_hash_indirect. If NTYPE is bfd_link_hash_common, NSIZE |
| is the size of the new symbol. */ |
| void (*multiple_common) |
| (struct bfd_link_info *, struct bfd_link_hash_entry *h, |
| bfd *nbfd, enum bfd_link_hash_type ntype, bfd_vma nsize); |
| /* A function which is called to add a symbol to a set. ENTRY is |
| the link hash table entry for the set itself (e.g., |
| __CTOR_LIST__). RELOC is the relocation to use for an entry in |
| the set when generating a relocatable file, and is also used to |
| get the size of the entry when generating an executable file. |
| ABFD, SEC and VALUE identify the value to add to the set. */ |
| void (*add_to_set) |
| (struct bfd_link_info *, struct bfd_link_hash_entry *entry, |
| bfd_reloc_code_real_type reloc, bfd *abfd, asection *sec, bfd_vma value); |
| /* A function which is called when the name of a g++ constructor or |
| destructor is found. This is only called by some object file |
| formats. CONSTRUCTOR is TRUE for a constructor, FALSE for a |
| destructor. This will use BFD_RELOC_CTOR when generating a |
| relocatable file. NAME is the name of the symbol found. ABFD, |
| SECTION and VALUE are the value of the symbol. */ |
| void (*constructor) |
| (struct bfd_link_info *, bool constructor, const char *name, |
| bfd *abfd, asection *sec, bfd_vma value); |
| /* A function which is called to issue a linker warning. For |
| example, this is called when there is a reference to a warning |
| symbol. WARNING is the warning to be issued. SYMBOL is the name |
| of the symbol which triggered the warning; it may be NULL if |
| there is none. ABFD, SECTION and ADDRESS identify the location |
| which trigerred the warning; either ABFD or SECTION or both may |
| be NULL if the location is not known. */ |
| void (*warning) |
| (struct bfd_link_info *, const char *warning, const char *symbol, |
| bfd *abfd, asection *section, bfd_vma address); |
| /* A function which is called when a relocation is attempted against |
| an undefined symbol. NAME is the symbol which is undefined. |
| ABFD, SECTION and ADDRESS identify the location from which the |
| reference is made. IS_FATAL indicates whether an undefined symbol is |
| a fatal error or not. In some cases SECTION may be NULL. */ |
| void (*undefined_symbol) |
| (struct bfd_link_info *, const char *name, bfd *abfd, |
| asection *section, bfd_vma address, bool is_fatal); |
| /* A function which is called when a reloc overflow occurs. ENTRY is |
| the link hash table entry for the symbol the reloc is against. |
| NAME is the name of the local symbol or section the reloc is |
| against, RELOC_NAME is the name of the relocation, and ADDEND is |
| any addend that is used. ABFD, SECTION and ADDRESS identify the |
| location at which the overflow occurs; if this is the result of a |
| bfd_section_reloc_link_order or bfd_symbol_reloc_link_order, then |
| ABFD will be NULL. */ |
| void (*reloc_overflow) |
| (struct bfd_link_info *, struct bfd_link_hash_entry *entry, |
| const char *name, const char *reloc_name, bfd_vma addend, |
| bfd *abfd, asection *section, bfd_vma address); |
| /* A function which is called when a dangerous reloc is performed. |
| MESSAGE is an appropriate message. |
| ABFD, SECTION and ADDRESS identify the location at which the |
| problem occurred; if this is the result of a |
| bfd_section_reloc_link_order or bfd_symbol_reloc_link_order, then |
| ABFD will be NULL. */ |
| void (*reloc_dangerous) |
| (struct bfd_link_info *, const char *message, |
| bfd *abfd, asection *section, bfd_vma address); |
| /* A function which is called when a reloc is found to be attached |
| to a symbol which is not being written out. NAME is the name of |
| the symbol. ABFD, SECTION and ADDRESS identify the location of |
| the reloc; if this is the result of a |
| bfd_section_reloc_link_order or bfd_symbol_reloc_link_order, then |
| ABFD will be NULL. */ |
| void (*unattached_reloc) |
| (struct bfd_link_info *, const char *name, |
| bfd *abfd, asection *section, bfd_vma address); |
| /* A function which is called when a symbol in notice_hash is |
| defined or referenced. H is the symbol, INH the indirect symbol |
| if applicable. ABFD, SECTION and ADDRESS are the (new) value of |
| the symbol. If SECTION is bfd_und_section, this is a reference. |
| FLAGS are the symbol BSF_* flags. */ |
| bool (*notice) |
| (struct bfd_link_info *, struct bfd_link_hash_entry *h, |
| struct bfd_link_hash_entry *inh, |
| bfd *abfd, asection *section, bfd_vma address, flagword flags); |
| /* Error or warning link info message. */ |
| void (*einfo) |
| (const char *fmt, ...); |
| /* General link info message. */ |
| void (*info) |
| (const char *fmt, ...); |
| /* Message to be printed in linker map file. */ |
| void (*minfo) |
| (const char *fmt, ...); |
| /* This callback provides a chance for users of the BFD library to |
| override its decision about whether to place two adjacent sections |
| into the same segment. */ |
| bool (*override_segment_assignment) |
| (struct bfd_link_info *, bfd * abfd, |
| asection * current_section, asection * previous_section, |
| bool new_segment); |
| /* This callback provides a chance for callers of the BFD to examine the |
| ELF (dynamic) string table once it is complete. */ |
| void (*examine_strtab) |
| (struct elf_strtab_hash *symstrtab); |
| /* This callback is called just before a symbol is swapped out, so that the |
| CTF machinery can look up symbols during construction. The name is |
| already an external strtab offset at this point. */ |
| void (*ctf_new_symbol) |
| (int symidx, struct elf_internal_sym *sym); |
| /* Likewise, for dynamic symbols. */ |
| void (*ctf_new_dynsym) |
| (int symidx, struct elf_internal_sym *sym); |
| /* This callback should emit the CTF section into a non-loadable section in |
| the output BFD named .ctf or a name beginning with ".ctf.". */ |
| void (*emit_ctf) |
| (void); |
| }; |
| |
| /* The linker builds link_order structures which tell the code how to |
| include input data in the output file. */ |
| |
| /* These are the types of link_order structures. */ |
| |
| enum bfd_link_order_type |
| { |
| bfd_undefined_link_order, /* Undefined. */ |
| bfd_indirect_link_order, /* Built from a section. */ |
| bfd_data_link_order, /* Set to explicit data. */ |
| bfd_section_reloc_link_order, /* Relocate against a section. */ |
| bfd_symbol_reloc_link_order /* Relocate against a symbol. */ |
| }; |
| |
| /* This is the link_order structure itself. These form a chain |
| attached to the output section whose contents they are describing. */ |
| |
| struct bfd_link_order |
| { |
| /* Next link_order in chain. */ |
| struct bfd_link_order *next; |
| /* Type of link_order. */ |
| enum bfd_link_order_type type; |
| /* Offset within output section in bytes. */ |
| bfd_vma offset; |
| /* Size within output section in octets. */ |
| bfd_size_type size; |
| /* Type specific information. */ |
| union |
| { |
| struct |
| { |
| /* Section to include. If this is used, then |
| section->output_section must be the section the |
| link_order is attached to, section->output_offset must |
| equal the link_order offset field, and section->size |
| must equal the link_order size field. Maybe these |
| restrictions should be relaxed someday. */ |
| asection *section; |
| } indirect; |
| struct |
| { |
| /* Size of contents, or zero when contents should be filled by |
| the architecture-dependent fill function. |
| A non-zero value allows filling of the output section |
| with an arbitrary repeated pattern. */ |
| unsigned int size; |
| /* Data to put into file. */ |
| bfd_byte *contents; |
| } data; |
| struct |
| { |
| /* Description of reloc to generate. Used for |
| bfd_section_reloc_link_order and |
| bfd_symbol_reloc_link_order. */ |
| struct bfd_link_order_reloc *p; |
| } reloc; |
| } u; |
| }; |
| |
| /* A linker order of type bfd_section_reloc_link_order or |
| bfd_symbol_reloc_link_order means to create a reloc against a |
| section or symbol, respectively. This is used to implement -Ur to |
| generate relocs for the constructor tables. The |
| bfd_link_order_reloc structure describes the reloc that BFD should |
| create. It is similar to a arelent, but I didn't use arelent |
| because the linker does not know anything about most symbols, and |
| any asymbol structure it creates will be partially meaningless. |
| This information could logically be in the bfd_link_order struct, |
| but I didn't want to waste the space since these types of relocs |
| are relatively rare. */ |
| |
| struct bfd_link_order_reloc |
| { |
| /* Reloc type. */ |
| bfd_reloc_code_real_type reloc; |
| |
| union |
| { |
| /* For type bfd_section_reloc_link_order, this is the section |
| the reloc should be against. This must be a section in the |
| output BFD, not any of the input BFDs. */ |
| asection *section; |
| /* For type bfd_symbol_reloc_link_order, this is the name of the |
| symbol the reloc should be against. */ |
| const char *name; |
| } u; |
| |
| /* Addend to use. The object file should contain zero. The BFD |
| backend is responsible for filling in the contents of the object |
| file correctly. For some object file formats (e.g., COFF) the |
| addend must be stored into in the object file, and for some |
| (e.g., SPARC a.out) it is kept in the reloc. */ |
| bfd_vma addend; |
| }; |
| |
| /* Allocate a new link_order for a section. */ |
| extern struct bfd_link_order *bfd_new_link_order (bfd *, asection *); |
| |
| struct bfd_section_already_linked; |
| |
| extern bool bfd_section_already_linked_table_init (void); |
| extern void bfd_section_already_linked_table_free (void); |
| extern bool _bfd_handle_already_linked |
| (struct bfd_section *, struct bfd_section_already_linked *, |
| struct bfd_link_info *); |
| |
| extern struct bfd_section *_bfd_nearby_section |
| (bfd *, struct bfd_section *, bfd_vma); |
| |
| extern void _bfd_fix_excluded_sec_syms |
| (bfd *, struct bfd_link_info *); |
| |
| /* These structures are used to describe version information for the |
| ELF linker. These structures could be manipulated entirely inside |
| BFD, but it would be a pain. Instead, the regular linker sets up |
| these structures, and then passes them into BFD. */ |
| |
| /* Glob pattern for a version. */ |
| |
| struct bfd_elf_version_expr |
| { |
| /* Next glob pattern for this version. */ |
| struct bfd_elf_version_expr *next; |
| /* Glob pattern. */ |
| const char *pattern; |
| /* Set if pattern is not a glob. */ |
| unsigned int literal : 1; |
| /* Defined by ".symver". */ |
| unsigned int symver : 1; |
| /* Defined by version script. */ |
| unsigned int script : 1; |
| /* Pattern type. */ |
| #define BFD_ELF_VERSION_C_TYPE 1 |
| #define BFD_ELF_VERSION_CXX_TYPE 2 |
| #define BFD_ELF_VERSION_JAVA_TYPE 4 |
| unsigned int mask : 3; |
| }; |
| |
| struct bfd_elf_version_expr_head |
| { |
| /* List of all patterns, both wildcards and non-wildcards. */ |
| struct bfd_elf_version_expr *list; |
| /* Hash table for non-wildcards. */ |
| void *htab; |
| /* Remaining patterns. */ |
| struct bfd_elf_version_expr *remaining; |
| /* What kind of pattern types are present in list (bitmask). */ |
| unsigned int mask; |
| }; |
| |
| /* Version dependencies. */ |
| |
| struct bfd_elf_version_deps |
| { |
| /* Next dependency for this version. */ |
| struct bfd_elf_version_deps *next; |
| /* The version which this version depends upon. */ |
| struct bfd_elf_version_tree *version_needed; |
| }; |
| |
| /* A node in the version tree. */ |
| |
| struct bfd_elf_version_tree |
| { |
| /* Next version. */ |
| struct bfd_elf_version_tree *next; |
| /* Name of this version. */ |
| const char *name; |
| /* Version number. */ |
| unsigned int vernum; |
| /* Regular expressions for global symbols in this version. */ |
| struct bfd_elf_version_expr_head globals; |
| /* Regular expressions for local symbols in this version. */ |
| struct bfd_elf_version_expr_head locals; |
| /* List of versions which this version depends upon. */ |
| struct bfd_elf_version_deps *deps; |
| /* Index of the version name. This is used within BFD. */ |
| unsigned int name_indx; |
| /* Whether this version tree was used. This is used within BFD. */ |
| int used; |
| /* Matching hook. */ |
| struct bfd_elf_version_expr *(*match) |
| (struct bfd_elf_version_expr_head *head, |
| struct bfd_elf_version_expr *prev, const char *sym); |
| }; |
| |
| struct bfd_elf_dynamic_list |
| { |
| struct bfd_elf_version_expr_head head; |
| struct bfd_elf_version_expr *(*match) |
| (struct bfd_elf_version_expr_head *head, |
| struct bfd_elf_version_expr *prev, const char *sym); |
| }; |
| |
| #endif |