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authorIan Lance Taylor <ian@airs.com>1998-05-01 22:44:27 +0000
committerIan Lance Taylor <ian@airs.com>1998-05-01 22:44:27 +0000
commit5de80887706009b194b8fb0b9efcc66b588e0a36 (patch)
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parentfbe293a6dd820e40b51a0acde1641ff576d7ec29 (diff)
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add target vector documentation
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-rw-r--r--bfd/doc/bfdint.texi640
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diff --git a/bfd/doc/bfdint.texi b/bfd/doc/bfdint.texi
index bb9bb73..85dac37 100644
--- a/bfd/doc/bfdint.texi
+++ b/bfd/doc/bfdint.texi
@@ -25,6 +25,7 @@ The initial version of this document was written by Ian Lance Taylor
@menu
* BFD glossary:: BFD glossary
* BFD guidelines:: BFD programming guidelines
+* BFD target vector:: BFD target vector
* BFD generated files:: BFD generated files
* BFD multiple compilations:: Files compiled multiple times in BFD
* BFD relocation handling:: BFD relocation handling
@@ -187,6 +188,645 @@ which may or may not be declared in system header files. Warnings about
ambiguous expressions and the like should always be fixed.
@end itemize
+@node BFD target vector
+@section BFD target vector
+@cindex bfd target vector
+@cindex target vector in bfd
+
+BFD supports multiple object file formats by using the @dfn{target
+vector}. This is simply a set of function pointers which implement
+behaviour that is specific to a particular object file format.
+
+In this section I list all of the entries in the target vector and
+describe what they do.
+
+@menu
+* BFD target vector miscellaneous:: Miscellaneous constants
+* BFD target vector swap:: Swapping functions
+* BFD target vector format:: Format type dependent functions
+* BFD_JUMP_TABLE macros:: BFD_JUMP_TABLE macros
+* BFD target vector generic:: Generic functions
+* BFD target vector copy:: Copy functions
+* BFD target vector core:: Core file support functions
+* BFD target vector archive:: Archive functions
+* BFD target vector symbols:: Symbol table functions
+* BFD target vector relocs:: Relocation support
+* BFD target vector write:: Output functions
+* BFD target vector link:: Linker functions
+* BFD target vector dynamic:: Dynamic linking information functions
+@end menu
+
+@node BFD target vector miscellaneous
+@subsection Miscellaneous constants
+
+The target vector starts with a set of constants.
+
+@table @samp
+@item name
+The name of the target vector. This is an arbitrary string. This is
+how the target vector is named in command line options for tools which
+use BFD, such as the @samp{-oformat} linker option.
+
+@item flavour
+A general description of the type of target. The following flavours are
+currently defined:
+@table @samp
+@item bfd_target_unknown_flavour
+Undefined or unknown.
+@item bfd_target_aout_flavour
+a.out.
+@item bfd_target_coff_flavour
+COFF.
+@item bfd_target_ecoff_flavour
+ECOFF.
+@item bfd_target_elf_flavour
+ELF.
+@item bfd_target_ieee_flavour
+IEEE-695.
+@item bfd_target_nlm_flavour
+NLM.
+@item bfd_target_oasys_flavour
+OASYS.
+@item bfd_target_tekhex_flavour
+Tektronix hex format.
+@item bfd_target_srec_flavour
+Motorola S-record format.
+@item bfd_target_ihex_flavour
+Intel hex format.
+@item bfd_target_som_flavour
+SOM (used on HP/UX).
+@item bfd_target_os9k_flavour
+os9000.
+@item bfd_target_versados_flavour
+VERSAdos.
+@item bfd_target_msdos_flavour
+MS-DOS.
+@item bfd_target_evax_flavour
+openVMS.
+@end table
+
+@item byteorder
+The byte order of data in the object file. One of
+@samp{BFD_ENDIAN_BIG}, @samp{BFD_ENDIAN_LITTLE}, or
+@samp{BFD_ENDIAN_UNKNOWN}. The latter would be used for a format such
+as S-records which do not record the architecture of the data.
+
+@item header_byteorder
+The byte order of header information in the object file. Normally the
+same as the @samp{byteorder} field, but there are certain cases where it
+may be different.
+
+@item object_flags
+Flags which may appear in the @samp{flags} field of a BFD with this
+format.
+
+@item section_flags
+Flags which may appear in the @samp{flags} field of a section within a
+BFD with this format.
+
+@item symbol_leading_char
+A character which the C compiler normally puts before a symbol. For
+example, an a.out compiler will typically generate the symbol
+@samp{_foo} for a function named @samp{foo} in the C source, in which
+case this field would be @samp{_}. If there is no such character, this
+field will be @samp{0}.
+
+@item ar_pad_char
+The padding character to use at the end of an archive name. Normally
+@samp{/}.
+
+@item ar_max_namelen
+The maximum length of a short name in an archive. Normally @samp{14}.
+
+@item backend_data
+A pointer to constant backend data. This is used by backends to store
+whatever additional information they need to distinguish similar target
+vectors which use the same sets of functions.
+@end table
+
+@node BFD target vector swap
+@subsection Swapping functions
+
+Every target vector has fuction pointers used for swapping information
+in and out of the target representation. There are two sets of
+functions: one for data information, and one for header information.
+Each set has three sizes: 64-bit, 32-bit, and 16-bit. Each size has
+three actual functions: put, get unsigned, and get signed.
+
+These 18 functions are used to convert data between the host and target
+representations.
+
+@node BFD target vector format
+@subsection Format type dependent functions
+
+Every target vector has three arrays of function pointers which are
+indexed by the BFD format type. The BFD format types are as follows:
+@table @samp
+@item bfd_unknown
+Unknown format. Not used for anything useful.
+@item bfd_object
+Object file.
+@item bfd_archive
+Archive file.
+@item bfd_core
+Core file.
+@end table
+
+The three arrays of function pointers are as follows:
+@table @samp
+@item bfd_check_format
+Check whether the BFD is of a particular format (object file, archive
+file, or core file) corresponding to this target vector. This is called
+by the @samp{bfd_check_format} function when examining an existing BFD.
+If the BFD matches the desired format, this function will initialize any
+format specific information such as the @samp{tdata} field of the BFD.
+This function must be called before any other BFD target vector function
+on a file opened for reading.
+
+@item bfd_set_format
+Set the format of a BFD which was created for output. This is called by
+the @samp{bfd_set_format} function after creating the BFD with a
+function such as @samp{bfd_openw}. This function will initialize format
+specific information required to write out an object file or whatever of
+the given format. This function must be called before any other BFD
+target vector function on a file opened for writing.
+
+@item bfd_write_contents
+Write out the contents of the BFD in the given format. This is called
+by @samp{bfd_close} function for a BFD opened for writing. This really
+should not be an array selected by format type, as the
+@samp{bfd_set_format} function provides all the required information.
+In fact, BFD will fail if a different format is used when calling
+through the @samp{bfd_set_format} and the @samp{bfd_write_contents}
+arrays; fortunately, since @samp{bfd_close} gets it right, this is a
+difficult error to make.
+@end table
+
+@node BFD_JUMP_TABLE macros
+@subsection @samp{BFD_JUMP_TABLE} macros
+@cindex @samp{BFD_JUMP_TABLE}
+
+Most target vectors are defined using @samp{BFD_JUMP_TABLE} macros.
+These macros take a single argument, which is a prefix applied to a set
+of functions. The macros are then used to initialize the fields in the
+target vector.
+
+For example, the @samp{BFD_JUMP_TABLE_RELOCS} macro defines three
+functions: @samp{_get_reloc_upper_bound}, @samp{_canonicalize_reloc},
+and @samp{_bfd_reloc_type_lookup}. A reference like
+@samp{BFD_JUMP_TABLE_RELOCS (foo)} will expand into three functions
+prefixed with @samp{foo}: @samp{foo_get_reloc_upper_found}, etc. The
+@samp{BFD_JUMP_TABLE_RELOCS} macro will be placed such that those three
+functions initialize the appropriate fields in the BFD target vector.
+
+This is done because it turns out that many different target vectors can
+shared certain classes of functions. For example, archives are similar
+on most platforms, so most target vectors can use the same archive
+functions. Those target vectors all use @samp{BFD_JUMP_TABLE_ARCHIVE}
+with the same argument, calling a set of functions which is defined in
+@file{archive.c}.
+
+Each of the @samp{BFD_JUMP_TABLE} macros is mentioned below along with
+the description of the function pointers which it defines. The function
+pointers will be described using the name without the prefix which the
+@samp{BFD_JUMP_TABLE} macro defines. This name is normally the same as
+the name of the field in the target vector structure. Any differences
+will be noted.
+
+@node BFD target vector generic
+@subsection Generic functions
+@cindex @samp{BFD_JUMP_TABLE_GENERIC}
+
+The @samp{BFD_JUMP_TABLE_GENERIC} macro is used for some catch all
+functions which don't easily fit into other categories.
+
+@table @samp
+@item _close_and_cleanup
+Free any target specific information associated with the BFD. This is
+called when any BFD is closed (the @samp{bfd_write_contents} function
+mentioned earlier is only called for a BFD opened for writing). Most
+targets use @samp{bfd_alloc} to allocate all target specific
+information, and therefore don't have to do anything in this function.
+This function pointer is typically set to
+@samp{_bfd_generic_close_and_cleanup}, which simply returns true.
+
+@item _bfd_free_cached_info
+Free any cached information associated with the BFD which can be
+recreated later if necessary. This is used to reduce the memory
+consumption required by programs using BFD. This is normally called via
+the @samp{bfd_free_cached_info} macro. It is used by the default
+archive routines when computing the archive map. Most targets do not
+do anything special for this entry point, and just set it to
+@samp{_bfd_generic_free_cached_info}, which simply returns true.
+
+@item _new_section_hook
+This is called from @samp{bfd_make_section_anyway} whenever a new
+section is created. Most targets use it to initialize section specific
+information. This function is called whether or not the section
+corresponds to an actual section in an actual BFD.
+
+@item _get_section_contents
+Get the contents of a section. This is called from
+@samp{bfd_get_section_contents}. Most targets set this to
+@samp{_bfd_generic_get_section_contents}, which does a @samp{bfd_seek}
+based on the section's @samp{filepos} field and a @samp{bfd_read}. The
+corresponding field in the target vector is named
+@samp{_bfd_get_section_contents}.
+
+@item _get_section_contents_in_window
+Set a @samp{bfd_window} to hold the contents of a section. This is
+called from @samp{bfd_get_section_contents_in_window}. The
+@samp{bfd_window} idea never really caught in, and I don't think this is
+ever called. Pretty much all targets implement this as
+@samp{bfd_generic_get_section_contents_in_window}, which uses
+@samp{bfd_get_section_contents} to do the right thing. The
+corresponding field in the target vector is named
+@samp{_bfd_get_section_contents_in_window}.
+@end table
+
+@node BFD target vector copy
+@subsection Copy functions
+@cindex @samp{BFD_JUMP_TABLE_COPY}
+
+The @samp{BFD_JUMP_TABLE_COPY} macro is used for functions which are
+called when copying BFDs, and for a couple of functions which deal with
+internal BFD information.
+
+@table @samp
+@item _bfd_copy_private_bfd_data
+This is called when copying a BFD, via @samp{bfd_copy_private_bfd_data}.
+If the input and output BFDs have the same format, this will copy any
+private information over. This is called after all the section contents
+have been written to the output file. Only a few targets do anything in
+this function.
+
+@item _bfd_merge_private_bfd_data
+This is called when linking, via @samp{bfd_merge_private_bfd_data}. It
+gives the backend linker code a chance to set any special flags in the
+output file based on the contents of the input file. Only a few targets
+do anything in this function.
+
+@item _bfd_copy_private_section_data
+This is similar to @samp{_bfd_copy_private_bfd_data}, but it is called
+for each section, via @samp{bfd_copy_private_section_data}. This
+function is called before any section contents have been written. Only
+a few targets do anything in this function.
+
+@item _bfd_copy_private_symbol_data
+This is called via @samp{bfd_copy_private_symbol_data}, but I don't
+think anything actually calls it. If it were defined, it could be used
+to copy private symbol data from one BFD to another. However, most BFDs
+store extra symbol information by allocating space which is larger than
+the @samp{asymbol} structure and storing private information in the
+extra space. Since @samp{objcopy} and other programs copy symbol
+information by copying pointers to @samp{asymbol} structures, the
+private symbol information is automatically copied as well. Most
+targets do not do anything in this function.
+
+@item _bfd_set_private_flags
+This is called via @samp{bfd_set_private_flags}. It is basically a hook
+for the assembler to set magic information. For example, the PowerPC
+ELF assembler uses it to set flags which appear in the e_flags field of
+the ELF header. Most targets do not do anything in this function.
+
+@item _bfd_print_private_bfd_data
+This is called by @samp{objdump} when the @samp{-p} option is used. It
+is called via @samp{bfd_print_private_data}. It prints any interesting
+information about the BFD which can not be otherwise represented by BFD
+and thus can not be printed by @samp{objdump}. Most targets do not do
+anything in this function.
+@end table
+
+@node BFD target vector core
+@subsection Core file support functions
+@cindex @samp{BFD_JUMP_TABLE_CORE}
+
+The @samp{BFD_JUMP_TABLE_CORE} macro is used for functions which deal
+with core files. Obviously, these functions only do something
+interesting for targets which have core file support.
+
+@table @samp
+@item _core_file_failing_command
+Given a core file, this returns the command which was run to produce the
+core file.
+
+@item _core_file_failing_signal
+Given a core file, this returns the signal number which produced the
+core file.
+
+@item _core_file_matches_executable_p
+Given a core file and a BFD for an executable, this returns whether the
+core file was generated by the executable.
+@end table
+
+@node BFD target vector archive
+@subsection Archive functions
+@cindex @samp{BFD_JUMP_TABLE_ARCHIVE}
+
+The @samp{BFD_JUMP_TABLE_ARCHIVE} macro is used for functions which deal
+with archive files. Most targets use COFF style archive files
+(including ELF targets), and these use @samp{_bfd_archive_coff} as the
+argument to @samp{BFD_JUMP_TABLE_ARCHIVE}. Some targets use BSD/a.out
+style archives, and these use @samp{_bfd_archive_bsd}. (The main
+difference between BSD and COFF archives is the format of the archive
+symbol table). Targets with no archive support use
+@samp{_bfd_noarchive}. Finally, a few targets have unusual archive
+handling.
+
+@table @samp
+@item _slurp_armap
+Read in the archive symbol table, storing it in private BFD data. This
+is normally called from the archive @samp{check_format} routine. The
+corresponding field in the target vector is named
+@samp{_bfd_slurp_armap}.
+
+@item _slurp_extended_name_table
+Read in the extended name table from the archive, if there is one,
+storing it in private BFD data. This is normally called from the
+archive @samp{check_format} routine. The corresponding field in the
+target vector is named @samp{_bfd_slurp_extended_name_table}.
+
+@item construct_extended_name_table
+Build and return an extended name table if one is needed to write out
+the archive. This also adjusts the archive headers to refer to the
+extended name table appropriately. This is normally called from the
+archive @samp{write_contents} routine. The corresponding field in the
+target vector is named @samp{_bfd_construct_extended_name_table}.
+
+@item _truncate_arname
+This copies a file name into an archive header, truncating it as
+required. It is normally called from the archive @samp{write_contents}
+routine. This function is more interesting in targets which do not
+support extended name tables, but I think the GNU @samp{ar} program
+always uses extended name tables anyhow. The corresponding field in the
+target vector is named @samp{_bfd_truncate_arname}.
+
+@item _write_armap
+Write out the archive symbol table using calls to @samp{bfd_write}.
+This is normally called from the archive @samp{write_contents} routine.
+The corresponding field in the target vector is named @samp{write_armap}
+(no leading underscore).
+
+@item _read_ar_hdr
+Read and parse an archive header. This handles expanding the archive
+header name into the real file name using the extended name table. This
+is called by routines which read the archive symbol table or the archive
+itself. The corresponding field in the target vector is named
+@samp{_bfd_read_ar_hdr_fn}.
+
+@item _openr_next_archived_file
+Given an archive and a BFD representing a file stored within the
+archive, return a BFD for the next file in the archive. This is called
+via @samp{bfd_openr_next_archived_file}. The corresponding field in the
+target vector is named @samp{openr_next_archived_file} (no leading
+underscore).
+
+@item _get_elt_at_index
+Given an archive and an index, return a BFD for the file in the archive
+corresponding to that entry in the archive symbol table. This is called
+via @samp{bfd_get_elt_at_index}. The corresponding field in the target
+vector is named @samp{_bfd_get_elt_at_index}.
+
+@item _generic_stat_arch_elt
+Do a stat on an element of an archive, returning information read from
+the archive header (modification time, uid, gid, file mode, size). This
+is called via @samp{bfd_stat_arch_elt}. The corresponding field in the
+target vector is named @samp{_bfd_stat_arch_elt}.
+
+@item _update_armap_timestamp
+After the entire contents of an archive have been written out, update
+the timestamp of the archive symbol table to be newer than that of the
+file. This is required for a.out style archives. This is normally
+called by the archive @samp{write_contents} routine. The corresponding
+field in the target vector is named @samp{_bfd_update_armap_timestamp}.
+@end table
+
+@node BFD target vector symbols
+@subsection Symbol table functions
+@cindex @samp{BFD_JUMP_TABLE_SYMBOLS}
+
+The @samp{BFD_JUMP_TABLE_SYMBOLS} macro is used for functions which deal
+with symbols.
+
+@table @samp
+@item _get_symtab_upper_bound
+Return a sensible upper bound on the amount of memory which will be
+required to read the symbol table. In practice most targets return the
+amount of memory required to hold @samp{asymbol} pointers for all the
+symbols plus a trailing @samp{NULL} entry, and store the actual symbol
+information in BFD private data. This is called via
+@samp{bfd_get_symtab_upper_bound}. The corresponding field in the
+target vector is named @samp{_bfd_get_symtab_upper_bound}.
+
+@item _get_symtab
+Read in the symbol table. This is called via
+@samp{bfd_canonicalize_symtab}. The corresponding field in the target
+vector is named @samp{_bfd_canonicalize_symtab}.
+
+@item _make_empty_symbol
+Create an empty symbol for the BFD. This is needed because most targets
+store extra information with each symbol by allocating a structure
+larger than an @samp{asymbol} and storing the extra information at the
+end. This function will allocate the right amount of memory, and return
+what looks like a pointer to an empty @samp{asymbol}. This is called
+via @samp{bfd_make_empty_symbol}. The corresponding field in the target
+vector is named @samp{_bfd_make_empty_symbol}.
+
+@item _print_symbol
+Print information about the symbol. This is called via
+@samp{bfd_print_symbol}. One of the arguments indicates what sort of
+information should be printed:
+@table @samp
+@item bfd_print_symbol_name
+Just print the symbol name.
+@item bfd_print_symbol_more
+Print the symbol name and some interesting flags. I don't think
+anything actually uses this.
+@item bfd_print_symbol_all
+Print all information about the symbol. This is used by @samp{objdump}
+when run with the @samp{-t} option.
+@end table
+The corresponding field in the target vector is named
+@samp{_bfd_print_symbol}.
+
+@item _get_symbol_info
+Return a standard set of information about the symbol. This is called
+via @samp{bfd_symbol_info}. The corresponding field in the target
+vector is named @samp{_bfd_get_symbol_info}.
+
+@item _bfd_is_local_label_name
+Return whether the given string would normally represent the name of a
+local label. This is called via @samp{bfd_is_local_label} and
+@samp{bfd_is_local_label_name}. Local labels are normally discarded by
+the assembler. In the linker, this defines the difference between the
+@samp{-x} and @samp{-X} options.
+
+@item _get_lineno
+Return line number information for a symbol. This is only meaningful
+for a COFF target. This is called when writing out COFF line numbers.
+
+@item _find_nearest_line
+Given an address within a section, use the debugging information to find
+the matching file name, function name, and line number, if any. This is
+called via @samp{bfd_find_nearest_line}. The corresponding field in the
+target vector is named @samp{_bfd_find_nearest_line}.
+
+@item _bfd_make_debug_symbol
+Make a debugging symbol. This is only meaningful for a COFF target,
+where it simply returns a symbol which will be placed in the
+@samp{N_DEBUG} section when it is written out. This is called via
+@samp{bfd_make_debug_symbol}.
+
+@item _read_minisymbols
+Minisymbols are used to reduce the memory requirements of programs like
+@samp{nm}. A minisymbol is a cookie pointing to internal symbol
+information which the caller can use to extract complete symbol
+information. This permits BFD to not convert all the symbols into
+generic form, but to instead convert them one at a time. This is called
+via @samp{bfd_read_minisymbols}. Most targets do not implement this,
+and just use generic support which is based on using standard
+@samp{asymbol} structures.
+
+@item _minisymbol_to_symbol
+Convert a minisymbol to a standard @samp{asymbol}. This is called via
+@samp{bfd_minisymbol_to_symbol}.
+@end table
+
+@node BFD target vector relocs
+@subsection Relocation support
+@cindex @samp{BFD_JUMP_TABLE_RELOCS}
+
+The @samp{BFD_JUMP_TABLE_RELOCS} macro is used for functions which deal
+with relocations.
+
+@table @samp
+@item _get_reloc_upper_bound
+Return a sensible upper bound on the amount of memory which will be
+required to read the relocations for a section. In practice most
+targets return the amount of memory required to hold @samp{arelent}
+pointers for all the relocations plus a trailing @samp{NULL} entry, and
+store the actual relocation information in BFD private data. This is
+called via @samp{bfd_get_reloc_upper_bound}.
+
+@item _canonicalize_reloc
+Return the relocation information for a section. This is called via
+@samp{bfd_canonicalize_reloc}. The corresponding field in the target
+vector is named @samp{_bfd_canonicalize_reloc}.
+
+@item _bfd_reloc_type_lookup
+Given a relocation code, return the corresponding howto structure
+(@pxref{BFD relocation codes}). This is called via
+@samp{bfd_reloc_type_lookup}. The corresponding field in the target
+vector is named @samp{reloc_type_lookup}.
+@end table
+
+@node BFD target vector write
+@subsection Output functions
+@cindex @samp{BFD_JUMP_TABLE_WRITE}
+
+The @samp{BFD_JUMP_TABLE_WRITE} macro is used for functions which deal
+with writing out a BFD.
+
+@table @samp
+@item _set_arch_mach
+Set the architecture and machine number for a BFD. This is called via
+@samp{bfd_set_arch_mach}. Most targets implement this by calling
+@samp{bfd_default_set_arch_mach}. The corresponding field in the target
+vector is named @samp{_bfd_set_arch_mach}.
+
+@item _set_section_contents
+Write out the contents of a section. This is called via
+@samp{bfd_set_section_contents}. The corresponding field in the target
+vector is named @samp{_bfd_set_section_contents}.
+@end table
+
+@node BFD target vector link
+@subsection Linker functions
+@cindex @samp{BFD_JUMP_TABLE_LINK}
+
+The @samp{BFD_JUMP_TABLE_LINK} macro is used for functions called by the
+linker.
+
+@table @samp
+@item _sizeof_headers
+Return the size of the header information required for a BFD. This is
+used to implement the @samp{SIZEOF_HEADERS} linker script function. It
+is normally used to align the first section at an efficient position on
+the page. This is called via @samp{bfd_sizeof_headers}. The
+corresponding field in the target vector is named
+@samp{_bfd_sizeof_headers}.
+
+@item _bfd_get_relocated_section_contents
+Read the contents of a section and apply the relocation information.
+This handles both a final link and a relocateable link; in the latter
+case, it adjust the relocation information as well. This is called via
+@samp{bfd_get_relocated_section_contents}. Most targets implement it by
+calling @samp{bfd_generic_get_relocated_section_contents}.
+
+@item _bfd_relax_section
+Try to use relaxation to shrink the size of a section. This is called
+by the linker when the @samp{-relax} option is used. This is called via
+@samp{bfd_relax_section}. Most targets do not support any sort of
+relaxation.
+
+@item _bfd_link_hash_table_create
+Create the symbol hash table to use for the linker. This linker hook
+permits the backend to control the size and information of the elements
+in the linker symbol hash table. This is called via
+@samp{bfd_link_hash_table_create}.
+
+@item _bfd_link_add_symbols
+Given an object file or an archive, add all symbols into the linker
+symbol hash table. Use callbacks to the linker to include archive
+elements in the link. This is called via @samp{bfd_link_add_symbols}.
+
+@item _bfd_final_link
+Finish the linking process. The linker calls this hook after all of the
+input files have been read, when it is ready to finish the link and
+generate the output file. This is called via @samp{bfd_final_link}.
+
+@item _bfd_link_split_section
+I don't know what this is for. Nothing seems to call it. The only
+non-trivial definition is in @file{som.c}.
+@end table
+
+@node BFD target vector dynamic
+@subsection Dynamic linking information functions
+@cindex @samp{BFD_JUMP_TABLE_DYNAMIC}
+
+The @samp{BFD_JUMP_TABLE_DYNAMIC} macro is used for functions which read
+dynamic linking information.
+
+@table @samp
+@item _get_dynamic_symtab_upper_bound
+Return a sensible upper bound on the amount of memory which will be
+required to read the dynamic symbol table. In practice most targets
+return the amount of memory required to hold @samp{asymbol} pointers for
+all the symbols plus a trailing @samp{NULL} entry, and store the actual
+symbol information in BFD private data. This is called via
+@samp{bfd_get_dynamic_symtab_upper_bound}. The corresponding field in
+the target vector is named @samp{_bfd_get_dynamic_symtab_upper_bound}.
+
+@item _canonicalize_dynamic_symtab
+Read the dynamic symbol table. This is called via
+@samp{bfd_canonicalize_dynamic_symtab}. The corresponding field in the
+target vector is named @samp{_bfd_canonicalize_dynamic_symtab}.
+
+@item _get_dynamic_reloc_upper_bound
+Return a sensible upper bound on the amount of memory which will be
+required to read the dynamic relocations. In practice most targets
+return the amount of memory required to hold @samp{arelent} pointers for
+all the relocations plus a trailing @samp{NULL} entry, and store the
+actual relocation information in BFD private data. This is called via
+@samp{bfd_get_dynamic_reloc_upper_bound}. The corresponding field in
+the target vector is named @samp{_bfd_get_dynamic_reloc_upper_bound}.
+
+@item _canonicalize_dynamic_reloc
+Read the dynamic relocations. This is called via
+@samp{bfd_canonicalize_dynamic_reloc}. The corresponding field in the
+target vector is named @samp{_bfd_canonicalize_dynamic_reloc}.
+@end table
+
@node BFD generated files
@section BFD generated files
@cindex generated files in bfd