/* bfdlink.h -- header file for BFD link routines
- Copyright (C) 1993-2015 Free Software Foundation, Inc.
+ 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.
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. */
/* Type of this entry. */
ENUM_BITFIELD (bfd_link_hash_type) type : 8;
- /* Symbol is referenced in a normal object file, as distict from a LTO
- IR object file. */
- unsigned int non_ir_ref : 1;
+ /* 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
{
automatically be non-NULL since the symbol will have been on the
undefined symbol list. */
struct bfd_link_hash_entry *next;
- bfd *abfd; /* BFD symbol was found in. */
+ /* BFD symbol was found in. */
+ bfd *abfd;
} undef;
/* bfd_link_hash_defined, bfd_link_hash_defweak. */
struct
{
struct bfd_link_hash_entry *next;
- asection *section; /* Symbol section. */
- bfd_vma value; /* Symbol value. */
+ /* 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;
- struct bfd_link_hash_entry *link; /* Real symbol. */
- const char *warning; /* Warning (bfd_link_hash_warning only). */
+ /* Real symbol. */
+ struct bfd_link_hash_entry *link;
+ /* Warning message (bfd_link_hash_warning only). */
+ const char *warning;
} i;
/* bfd_link_hash_common. */
struct
the union; this structure is a major space user in the
linker. */
struct bfd_link_hash_common_entry *p;
- bfd_size_type size; /* Common symbol size. */
+ /* Common symbol size. */
+ bfd_size_type size;
} c;
} u;
};
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 *, bfd_boolean create,
- bfd_boolean copy, bfd_boolean follow);
+ (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 *, bfd_boolean,
- bfd_boolean, bfd_boolean);
+ (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. */
/* Traverse a link hash table. */
extern void bfd_link_hash_traverse
(struct bfd_link_hash_table *,
- bfd_boolean (*) (struct bfd_link_hash_entry *, void *),
+ bool (*) (struct bfd_link_hash_entry *, void *),
void *);
/* Add an entry to the undefs list. */
(struct bfd_link_hash_table *table);
/* Read symbols and cache symbol pointer array in outsymbols. */
-extern bfd_boolean bfd_generic_link_read_symbols (bfd *);
+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
{
allowed to set the value. */
RM_NOT_YET_SET = 0,
RM_IGNORE,
- RM_GENERATE_WARNING,
- RM_GENERATE_ERROR
+ 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. */
{
flag_type with;
const char *name;
- bfd_boolean valid;
+ bool valid;
struct flag_info_list *next;
};
flagword only_with_flags;
flagword not_with_flags;
struct flag_info_list *flag_list;
- bfd_boolean flags_initialized;
+ bool flags_initialized;
};
struct bfd_elf_dynamic_list;
struct bfd_elf_version_tree;
-/* This structure holds all the information needed to communicate
- between BFD and the linker when doing a link. */
+/* Types of output. */
-struct bfd_link_info
+enum output_type
{
- /* TRUE if BFD should generate a shared object (or a pie). */
- unsigned int shared: 1;
+ type_pde,
+ type_pie,
+ type_relocatable,
+ type_dll,
+};
- /* TRUE if generating an executable, position independent or not. */
- unsigned int executable : 1;
+#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))
- /* TRUE if generating a position independent executable. */
- unsigned int pie: 1;
+/* This structure holds all the information needed to communicate
+ between BFD and the linker when doing a link. */
- /* TRUE if BFD should generate a relocatable object file. */
- unsigned int relocatable: 1;
+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 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. */
+ 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.
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 PT_GNU_RELRO segment should be created. */
unsigned int relro: 1;
- /* TRUE if .eh_frame_hdr section and PT_GNU_EH_FRAME ELF segment
- should be created. */
- unsigned int eh_frame_hdr: 1;
+ /* TRUE if separate code segment should be created. */
+ unsigned int separate_code: 1;
- /* TRUE if we should warn when adding a DT_TEXTREL to a shared object. */
- unsigned int warn_shared_textrel: 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;
- /* TRUE if we should error when adding a DT_TEXTREL. */
- unsigned int error_textrel: 1;
+ /* 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;
statics. */
unsigned int task_link: 1;
- /* TRUE if ok to have multiple definition. */
+ /* 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 the linker script contained an explicit PHDRS command. */
unsigned int user_phdrs: 1;
- /* TRUE if BND prefix in PLT entries is always generated. */
- unsigned int bndplt: 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
/* 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;
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).
/* 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;
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. */
/* 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;
struct bfd_elf_version_tree *version_info;
};
+/* 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. Except for the info functions, the first
- argument to each callback function is the bfd_link_info structure
- being used and each function returns a boolean value. If the
- function returns FALSE, then the BFD function which called it should
- return with a failure indication. */
+ by the BFD linker routines. */
struct bfd_link_callbacks
{
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. */
- bfd_boolean (*add_archive_element)
+ 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. */
- bfd_boolean (*multiple_definition)
+ 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
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. */
- bfd_boolean (*multiple_common)
+ 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 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. */
- bfd_boolean (*add_to_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. 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. */
- bfd_boolean (*constructor)
- (struct bfd_link_info *, bfd_boolean constructor, const char *name,
+ 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
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. */
- bfd_boolean (*warning)
+ 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
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. */
- bfd_boolean (*undefined_symbol)
+ void (*undefined_symbol)
(struct bfd_link_info *, const char *name, bfd *abfd,
- asection *section, bfd_vma address, bfd_boolean is_fatal);
+ 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
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. */
- bfd_boolean (*reloc_overflow)
+ 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);
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. */
- bfd_boolean (*reloc_dangerous)
+ 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
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. */
- bfd_boolean (*unattached_reloc)
+ 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
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. */
- bfd_boolean (*notice)
+ 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);
/* 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. */
- bfd_boolean (*override_segment_assignment)
+ bool (*override_segment_assignment)
(struct bfd_link_info *, bfd * abfd,
asection * current_section, asection * previous_section,
- bfd_boolean new_segment);
+ 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);
};
\f
/* The linker builds link_order structures which tell the code how to
struct bfd_link_order *next;
/* Type of link_order. */
enum bfd_link_order_type type;
- /* Offset within output section. */
+ /* Offset within output section in bytes. */
bfd_vma offset;
- /* Size within output section. */
+ /* Size within output section in octets. */
bfd_size_type size;
/* Type specific information. */
union
/* 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
projects / thirdparty / binutils-gdb.git / blobdiff