\input texinfo @c -*- Texinfo -*- @setfilename binutils.info @c Copyright 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. @c man begin INCLUDE @include config.texi @c man end @ifinfo @format START-INFO-DIR-ENTRY * Binutils: (binutils). The GNU binary utilities. * ar: (binutils)ar. Create, modify, and extract from archives * nm: (binutils)nm. List symbols from object files * objcopy: (binutils)objcopy. Copy and translate object files * objdump: (binutils)objdump. Display information from object files * ranlib: (binutils)ranlib. Generate index to archive contents * readelf: (binutils)readelf. Display the contents of ELF format files. * size: (binutils)size. List section sizes and total size * strings: (binutils)strings. List printable strings from files * strip: (binutils)strip. Discard symbols * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt * addr2line: (binutils)addr2line. Convert addresses to file and line * nlmconv: (binutils)nlmconv. Converts object code into an NLM * windres: (binutils)windres. Manipulate Windows resources * dlltool: (binutils)dlltool. Create files needed to build and use DLLs END-INFO-DIR-ENTRY @end format @end ifinfo @ifinfo @c man begin COPYRIGHT Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled ``GNU Free Documentation License''. @c man end @ignore Permission is granted to process this file through TeX and print the results, provided the printed document carries a copying permission notice identical to this one except for the removal of this paragraph (this paragraph not being relevant to the printed manual). @end ignore @end ifinfo @synindex ky cp @c @c This file documents the GNU binary utilities "ar", "ld", "objcopy", @c "objdump", "nm", "size", "strings", "strip", "readelf" and "ranlib". @c @c Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, @c 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. @c @c This text may be freely distributed under the terms of the GNU @c Free Documentation License. @c @setchapternewpage odd @settitle @sc{gnu} Binary Utilities @titlepage @finalout @title The @sc{gnu} Binary Utilities @subtitle Version @value{VERSION} @sp 1 @subtitle @value{UPDATED} @author Roland H. Pesch @author Jeffrey M. Osier @author Cygnus Support @page @tex {\parskip=0pt \hfill Cygnus Support\par \hfill \TeX{}info \texinfoversion\par } @end tex @vskip 0pt plus 1filll Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled ``GNU Free Documentation License''. @end titlepage @node Top @top Introduction @cindex version This brief manual contains documentation for the @sc{gnu} binary utilities (collectively version @value{VERSION}): @iftex @table @code @item ar Create, modify, and extract from archives @item nm List symbols from object files @item objcopy Copy and translate object files @item objdump Display information from object files @item ranlib Generate index to archive contents @item readelf Display the contents of ELF format files. @item size List file section sizes and total size @item strings List printable strings from files @item strip Discard symbols @item c++filt Demangle encoded C++ symbols (on MS-DOS, this program is named @code{cxxfilt}) @item addr2line Convert addresses into file names and line numbers @item nlmconv Convert object code into a Netware Loadable Module @item windres Manipulate Windows resources @item dlltool Create the files needed to build and use Dynamic Link Libraries @end table @end iftex This document is distributed under the terms of the GNU Free Documentation License. A copy of the license is included in the section entitled "GNU Free Documentation License". @menu * ar:: Create, modify, and extract from archives * nm:: List symbols from object files * objcopy:: Copy and translate object files * objdump:: Display information from object files * ranlib:: Generate index to archive contents * readelf:: Display the contents of ELF format files. * size:: List section sizes and total size * strings:: List printable strings from files * strip:: Discard symbols * c++filt:: Filter to demangle encoded C++ symbols * cxxfilt: c++filt. MS-DOS name for c++filt * addr2line:: Convert addresses to file and line * nlmconv:: Converts object code into an NLM * windres:: Manipulate Windows resources * dlltool:: Create files needed to build and use DLLs * Common Options:: Command-line options for all utilities * Selecting The Target System:: How these utilities determine the target. * Reporting Bugs:: Reporting Bugs * GNU Free Documentation License:: GNU Free Documentation License * Index:: Index @end menu @node ar @chapter ar @kindex ar @cindex archives @cindex collections of files @c man title ar create, modify, and extract from archives @smallexample ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}] ar -M [ }), and continues executing even after errors. If you redirect standard input to a script file, no prompts are issued, and @command{ar} abandons execution (with a nonzero exit code) on any error. The @command{ar} command language is @emph{not} designed to be equivalent to the command-line options; in fact, it provides somewhat less control over archives. The only purpose of the command language is to ease the transition to @sc{gnu} @command{ar} for developers who already have scripts written for the MRI ``librarian'' program. The syntax for the @command{ar} command language is straightforward: @itemize @bullet @item commands are recognized in upper or lower case; for example, @code{LIST} is the same as @code{list}. In the following descriptions, commands are shown in upper case for clarity. @item a single command may appear on each line; it is the first word on the line. @item empty lines are allowed, and have no effect. @item comments are allowed; text after either of the characters @samp{*} or @samp{;} is ignored. @item Whenever you use a list of names as part of the argument to an @command{ar} command, you can separate the individual names with either commas or blanks. Commas are shown in the explanations below, for clarity. @item @samp{+} is used as a line continuation character; if @samp{+} appears at the end of a line, the text on the following line is considered part of the current command. @end itemize Here are the commands you can use in @command{ar} scripts, or when using @command{ar} interactively. Three of them have special significance: @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is a temporary file required for most of the other commands. @code{SAVE} commits the changes so far specified by the script. Prior to @code{SAVE}, commands affect only the temporary copy of the current archive. @table @code @item ADDLIB @var{archive} @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module}) Add all the contents of @var{archive} (or, if specified, each named @var{module} from @var{archive}) to the current archive. Requires prior use of @code{OPEN} or @code{CREATE}. @item ADDMOD @var{member}, @var{member}, @dots{} @var{member} @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}" @c else like "ar q..." Add each named @var{member} as a module in the current archive. Requires prior use of @code{OPEN} or @code{CREATE}. @item CLEAR Discard the contents of the current archive, canceling the effect of any operations since the last @code{SAVE}. May be executed (with no effect) even if no current archive is specified. @item CREATE @var{archive} Creates an archive, and makes it the current archive (required for many other commands). The new archive is created with a temporary name; it is not actually saved as @var{archive} until you use @code{SAVE}. You can overwrite existing archives; similarly, the contents of any existing file named @var{archive} will not be destroyed until @code{SAVE}. @item DELETE @var{module}, @var{module}, @dots{} @var{module} Delete each listed @var{module} from the current archive; equivalent to @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}. Requires prior use of @code{OPEN} or @code{CREATE}. @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile} List each named @var{module} present in @var{archive}. The separate command @code{VERBOSE} specifies the form of the output: when verbose output is off, output is like that of @samp{ar -t @var{archive} @var{module}@dots{}}. When verbose output is on, the listing is like @samp{ar -tv @var{archive} @var{module}@dots{}}. Output normally goes to the standard output stream; however, if you specify @var{outputfile} as a final argument, @command{ar} directs the output to that file. @item END Exit from @command{ar}, with a @code{0} exit code to indicate successful completion. This command does not save the output file; if you have changed the current archive since the last @code{SAVE} command, those changes are lost. @item EXTRACT @var{module}, @var{module}, @dots{} @var{module} Extract each named @var{module} from the current archive, writing them into the current directory as separate files. Equivalent to @samp{ar -x @var{archive} @var{module}@dots{}}. Requires prior use of @code{OPEN} or @code{CREATE}. @ignore @c FIXME Tokens but no commands??? @item FULLDIR @item HELP @end ignore @item LIST Display full contents of the current archive, in ``verbose'' style regardless of the state of @code{VERBOSE}. The effect is like @samp{ar tv @var{archive}}. (This single command is a @sc{gnu} @command{ar} enhancement, rather than present for MRI compatibility.) Requires prior use of @code{OPEN} or @code{CREATE}. @item OPEN @var{archive} Opens an existing archive for use as the current archive (required for many other commands). Any changes as the result of subsequent commands will not actually affect @var{archive} until you next use @code{SAVE}. @item REPLACE @var{module}, @var{module}, @dots{} @var{module} In the current archive, replace each existing @var{module} (named in the @code{REPLACE} arguments) from files in the current working directory. To execute this command without errors, both the file, and the module in the current archive, must exist. Requires prior use of @code{OPEN} or @code{CREATE}. @item VERBOSE Toggle an internal flag governing the output from @code{DIRECTORY}. When the flag is on, @code{DIRECTORY} output matches output from @samp{ar -tv }@dots{}. @item SAVE Commit your changes to the current archive, and actually save it as a file with the name specified in the last @code{CREATE} or @code{OPEN} command. Requires prior use of @code{OPEN} or @code{CREATE}. @end table @iftex @node ld @chapter ld @cindex linker @kindex ld The @sc{gnu} linker @command{ld} is now described in a separate manual. @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}. @end iftex @node nm @chapter nm @cindex symbols @kindex nm @c man title nm list symbols from object files @smallexample @c man begin SYNOPSIS nm nm [@option{-a}|@option{--debug-syms}] [@option{-g}|@option{--extern-only}] [@option{-B}] [@option{-C}|@option{--demangle}[=@var{style}]] [@option{-D}|@option{--dynamic}] [@option{-S}|@option{--print-size}] [@option{-s}|@option{--print-armap}] [@option{-A}|@option{-o}|@option{--print-file-name}][@option{--special-syms}] [@option{-n}|@option{-v}|@option{--numeric-sort}] [@option{-p}|@option{--no-sort}] [@option{-r}|@option{--reverse-sort}] [@option{--size-sort}] [@option{-u}|@option{--undefined-only}] [@option{-t} @var{radix}|@option{--radix=}@var{radix}] [@option{-P}|@option{--portability}] [@option{--target=}@var{bfdname}] [@option{-f}@var{format}|@option{--format=}@var{format}] [@option{--defined-only}] [@option{-l}|@option{--line-numbers}] [@option{--no-demangle}] [@option{-V}|@option{--version}] [@option{-X 32_64}] [@option{--help}] [@var{objfile}@dots{}] @c man end @end smallexample @c man begin DESCRIPTION nm @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}. If no object files are listed as arguments, @command{nm} assumes the file @file{a.out}. For each symbol, @command{nm} shows: @itemize @bullet @item The symbol value, in the radix selected by options (see below), or hexadecimal by default. @item The symbol type. At least the following types are used; others are, as well, depending on the object file format. If lowercase, the symbol is local; if uppercase, the symbol is global (external). @c Some more detail on exactly what these symbol types are used for @c would be nice. @table @code @item A The symbol's value is absolute, and will not be changed by further linking. @item B The symbol is in the uninitialized data section (known as BSS). @item C The symbol is common. Common symbols are uninitialized data. When linking, multiple common symbols may appear with the same name. If the symbol is defined anywhere, the common symbols are treated as undefined references. @ifclear man For more details on common symbols, see the discussion of --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}. @end ifclear @item D The symbol is in the initialized data section. @item G The symbol is in an initialized data section for small objects. Some object file formats permit more efficient access to small data objects, such as a global int variable as opposed to a large global array. @item I The symbol is an indirect reference to another symbol. This is a @sc{gnu} extension to the a.out object file format which is rarely used. @item N The symbol is a debugging symbol. @item R The symbol is in a read only data section. @item S The symbol is in an uninitialized data section for small objects. @item T The symbol is in the text (code) section. @item U The symbol is undefined. @item V The symbol is a weak object. When a weak defined symbol is linked with a normal defined symbol, the normal defined symbol is used with no error. When a weak undefined symbol is linked and the symbol is not defined, the value of the weak symbol becomes zero with no error. @item W The symbol is a weak symbol that has not been specifically tagged as a weak object symbol. When a weak defined symbol is linked with a normal defined symbol, the normal defined symbol is used with no error. When a weak undefined symbol is linked and the symbol is not defined, the value of the symbol is determined in a system-specific manner without error. On some systems, uppercase indicates that a default value has been specified. @item - The symbol is a stabs symbol in an a.out object file. In this case, the next values printed are the stabs other field, the stabs desc field, and the stab type. Stabs symbols are used to hold debugging information. @ifclear man For more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The ``stabs'' debug format}. @end ifclear @item ? The symbol type is unknown, or object file format specific. @end table @item The symbol name. @end itemize @c man end @c man begin OPTIONS nm The long and short forms of options, shown here as alternatives, are equivalent. @table @env @item -A @itemx -o @itemx --print-file-name @cindex input file name @cindex file name @cindex source file name Precede each symbol by the name of the input file (or archive member) in which it was found, rather than identifying the input file once only, before all of its symbols. @item -a @itemx --debug-syms @cindex debugging symbols Display all symbols, even debugger-only symbols; normally these are not listed. @item -B @cindex @command{nm} format @cindex @command{nm} compatibility The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}). @item -C @itemx --demangle[=@var{style}] @cindex demangling in nm Decode (@dfn{demangle}) low-level symbol names into user-level names. Besides removing any initial underscore prepended by the system, this makes C++ function names readable. Different compilers have different mangling styles. The optional demangling style argument can be used to choose an appropriate demangling style for your compiler. @xref{c++filt}, for more information on demangling. @item --no-demangle Do not demangle low-level symbol names. This is the default. @item -D @itemx --dynamic @cindex dynamic symbols Display the dynamic symbols rather than the normal symbols. This is only meaningful for dynamic objects, such as certain types of shared libraries. @item -f @var{format} @itemx --format=@var{format} @cindex @command{nm} format @cindex @command{nm} compatibility Use the output format @var{format}, which can be @code{bsd}, @code{sysv}, or @code{posix}. The default is @code{bsd}. Only the first character of @var{format} is significant; it can be either upper or lower case. @item -g @itemx --extern-only @cindex external symbols Display only external symbols. @item -l @itemx --line-numbers @cindex symbol line numbers For each symbol, use debugging information to try to find a filename and line number. For a defined symbol, look for the line number of the address of the symbol. For an undefined symbol, look for the line number of a relocation entry which refers to the symbol. If line number information can be found, print it after the other symbol information. @item -n @itemx -v @itemx --numeric-sort Sort symbols numerically by their addresses, rather than alphabetically by their names. @item -p @itemx --no-sort @cindex sorting symbols Do not bother to sort the symbols in any order; print them in the order encountered. @item -P @itemx --portability Use the POSIX.2 standard output format instead of the default format. Equivalent to @samp{-f posix}. @item -S @itemx --print-size Print size, not the value, of defined symbols for the @code{bsd} output format. @item -s @itemx --print-armap @cindex symbol index, listing When listing symbols from archive members, include the index: a mapping (stored in the archive by @command{ar} or @command{ranlib}) of which modules contain definitions for which names. @item -r @itemx --reverse-sort Reverse the order of the sort (whether numeric or alphabetic); let the last come first. @item --size-sort Sort symbols by size. The size is computed as the difference between the value of the symbol and the value of the symbol with the next higher value. If the @code{bsd} output format is used the size of the symbol is printed, rather than the value, and @samp{-S} must be used in order both size and value to be printed. @item --special-syms Display symbols which have a target-specific special meaning. These symbols are usually used by the target for some special processing and are not normally helpful when included included in the normal symbol lists. For example for ARM targets this option would skip the mapping symbols used to mark transistions between ARM code, THUMB code and data. @item -t @var{radix} @itemx --radix=@var{radix} Use @var{radix} as the radix for printing the symbol values. It must be @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal. @item --target=@var{bfdname} @cindex object code format Specify an object code format other than your system's default format. @xref{Target Selection}, for more information. @item -u @itemx --undefined-only @cindex external symbols @cindex undefined symbols Display only undefined symbols (those external to each object file). @item --defined-only @cindex external symbols @cindex undefined symbols Display only defined symbols for each object file. @item -V @itemx --version Show the version number of @command{nm} and exit. @item -X This option is ignored for compatibility with the AIX version of @command{nm}. It takes one parameter which must be the string @option{32_64}. The default mode of AIX @command{nm} corresponds to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}. @item --help Show a summary of the options to @command{nm} and exit. @end table @c man end @ignore @c man begin SEEALSO nm ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}. @c man end @end ignore @node objcopy @chapter objcopy @c man title objcopy copy and translate object files @smallexample @c man begin SYNOPSIS objcopy objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}] [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}] [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}] [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}] [@option{-S}|@option{--strip-all}] [@option{-g}|@option{--strip-debug}] [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}] [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}] [@option{--strip-unneeded-symbol=}@var{symbolname}] [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}] [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}] [@option{--globalize-symbol=}@var{symbolname}] [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}] [@option{-w}|@option{--wildcard}] [@option{-x}|@option{--discard-all}] [@option{-X}|@option{--discard-locals}] [@option{-b} @var{byte}|@option{--byte=}@var{byte}] [@option{-i} @var{interleave}|@option{--interleave=}@var{interleave}] [@option{-j} @var{sectionname}|@option{--only-section=}@var{sectionname}] [@option{-R} @var{sectionname}|@option{--remove-section=}@var{sectionname}] [@option{-p}|@option{--preserve-dates}] [@option{--debugging}] [@option{--gap-fill=}@var{val}] [@option{--pad-to=}@var{address}] [@option{--set-start=}@var{val}] [@option{--adjust-start=}@var{incr}] [@option{--change-addresses=}@var{incr}] [@option{--change-section-address} @var{section}@{=,+,-@}@var{val}] [@option{--change-section-lma} @var{section}@{=,+,-@}@var{val}] [@option{--change-section-vma} @var{section}@{=,+,-@}@var{val}] [@option{--change-warnings}] [@option{--no-change-warnings}] [@option{--set-section-flags} @var{section}=@var{flags}] [@option{--add-section} @var{sectionname}=@var{filename}] [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]] [@option{--change-leading-char}] [@option{--remove-leading-char}] [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}] [@option{--redefine-sym} @var{old}=@var{new}] [@option{--redefine-syms=}@var{filename}] [@option{--weaken}] [@option{--keep-symbols=}@var{filename}] [@option{--strip-symbols=}@var{filename}] [@option{--strip-unneeded-symbols=}@var{filename}] [@option{--keep-global-symbols=}@var{filename}] [@option{--localize-symbols=}@var{filename}] [@option{--globalize-symbols=}@var{filename}] [@option{--weaken-symbols=}@var{filename}] [@option{--alt-machine-code=}@var{index}] [@option{--prefix-symbols=}@var{string}] [@option{--prefix-sections=}@var{string}] [@option{--prefix-alloc-sections=}@var{string}] [@option{--add-gnu-debuglink=}@var{path-to-file}] [@option{--keep-file-symbols}] [@option{--only-keep-debug}] [@option{--writable-text}] [@option{--readonly-text}] [@option{--pure}] [@option{--impure}] [@option{-v}|@option{--verbose}] [@option{-V}|@option{--version}] [@option{--help}] [@option{--info}] @var{infile} [@var{outfile}] @c man end @end smallexample @c man begin DESCRIPTION objcopy The @sc{gnu} @command{objcopy} utility copies the contents of an object file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to read and write the object files. It can write the destination object file in a format different from that of the source object file. The exact behavior of @command{objcopy} is controlled by command-line options. Note that @command{objcopy} should be able to copy a fully linked file between any two formats. However, copying a relocatable object file between any two formats may not work as expected. @command{objcopy} creates temporary files to do its translations and deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its translation work; it has access to all the formats described in @sc{bfd} and thus is able to recognize most formats without being told explicitly. @xref{BFD,,BFD,ld.info,Using LD}. @command{objcopy} can be used to generate S-records by using an output target of @samp{srec} (e.g., use @samp{-O srec}). @command{objcopy} can be used to generate a raw binary file by using an output target of @samp{binary} (e.g., use @option{-O binary}). When @command{objcopy} generates a raw binary file, it will essentially produce a memory dump of the contents of the input object file. All symbols and relocation information will be discarded. The memory dump will start at the load address of the lowest section copied into the output file. When generating an S-record or a raw binary file, it may be helpful to use @option{-S} to remove sections containing debugging information. In some cases @option{-R} will be useful to remove sections which contain information that is not needed by the binary file. Note---@command{objcopy} is not able to change the endianness of its input files. If the input format has an endianness (some formats do not), @command{objcopy} can only copy the inputs into file formats that have the same endianness or which have no endianness (e.g., @samp{srec}). @c man end @c man begin OPTIONS objcopy @table @env @item @var{infile} @itemx @var{outfile} The input and output files, respectively. If you do not specify @var{outfile}, @command{objcopy} creates a temporary file and destructively renames the result with the name of @var{infile}. @item -I @var{bfdname} @itemx --input-target=@var{bfdname} Consider the source file's object format to be @var{bfdname}, rather than attempting to deduce it. @xref{Target Selection}, for more information. @item -O @var{bfdname} @itemx --output-target=@var{bfdname} Write the output file using the object format @var{bfdname}. @xref{Target Selection}, for more information. @item -F @var{bfdname} @itemx --target=@var{bfdname} Use @var{bfdname} as the object format for both the input and the output file; i.e., simply transfer data from source to destination with no translation. @xref{Target Selection}, for more information. @item -B @var{bfdarch} @itemx --binary-architecture=@var{bfdarch} Useful when transforming a raw binary input file into an object file. In this case the output architecture can be set to @var{bfdarch}. This option will be ignored if the input file has a known @var{bfdarch}. You can access this binary data inside a program by referencing the special symbols that are created by the conversion process. These symbols are called _binary_@var{objfile}_start, _binary_@var{objfile}_end and _binary_@var{objfile}_size. e.g. you can transform a picture file into an object file and then access it in your code using these symbols. @item -j @var{sectionname} @itemx --only-section=@var{sectionname} Copy only the named section from the input file to the output file. This option may be given more than once. Note that using this option inappropriately may make the output file unusable. @item -R @var{sectionname} @itemx --remove-section=@var{sectionname} Remove any section named @var{sectionname} from the output file. This option may be given more than once. Note that using this option inappropriately may make the output file unusable. @item -S @itemx --strip-all Do not copy relocation and symbol information from the source file. @item -g @itemx --strip-debug Do not copy debugging symbols or sections from the source file. @item --strip-unneeded Strip all symbols that are not needed for relocation processing. @item -K @var{symbolname} @itemx --keep-symbol=@var{symbolname} When stripping symbols, keep symbol @var{symbolname} even if it would normally be stripped. This option may be given more than once. @item -N @var{symbolname} @itemx --strip-symbol=@var{symbolname} Do not copy symbol @var{symbolname} from the source file. This option may be given more than once. @item --strip-unneeded-symbol=@var{symbolname} Do not copy symbol @var{symbolname} from the source file unless it is needed by a relocation. This option may be given more than once. @item -G @var{symbolname} @itemx --keep-global-symbol=@var{symbolname} Keep only symbol @var{symbolname} global. Make all other symbols local to the file, so that they are not visible externally. This option may be given more than once. @item -L @var{symbolname} @itemx --localize-symbol=@var{symbolname} Make symbol @var{symbolname} local to the file, so that it is not visible externally. This option may be given more than once. @item -W @var{symbolname} @itemx --weaken-symbol=@var{symbolname} Make symbol @var{symbolname} weak. This option may be given more than once. @item --globalize-symbol=@var{symbolname} Give symbol @var{symbolname} global scoping so that it is visible outside of the file in which it is defined. This option may be given more than once. @item -w @itemx --wildcard Permit regular expressions in @var{symbolname}s used in other command line options. The question mark (?), asterisk (*), backslash (\) and square brackets ([]) operators can be used anywhere in the symbol name. If the first character of the symbol name is the exclamation point (!) then the sense of the switch is reversed for that symbol. For example: @smallexample -w -W !foo -W fo* @end smallexample would cause objcopy to weaken all symbols that start with ``fo'' except for the symbol ``foo''. @item -x @itemx --discard-all Do not copy non-global symbols from the source file. @c FIXME any reason to prefer "non-global" to "local" here? @item -X @itemx --discard-locals Do not copy compiler-generated local symbols. (These usually start with @samp{L} or @samp{.}.) @item -b @var{byte} @itemx --byte=@var{byte} Keep only every @var{byte}th byte of the input file (header data is not affected). @var{byte} can be in the range from 0 to @var{interleave}-1, where @var{interleave} is given by the @option{-i} or @option{--interleave} option, or the default of 4. This option is useful for creating files to program @sc{rom}. It is typically used with an @code{srec} output target. @item -i @var{interleave} @itemx --interleave=@var{interleave} Only copy one out of every @var{interleave} bytes. Select which byte to copy with the @option{-b} or @option{--byte} option. The default is 4. @command{objcopy} ignores this option if you do not specify either @option{-b} or @option{--byte}. @item -p @itemx --preserve-dates Set the access and modification dates of the output file to be the same as those of the input file. @item --debugging Convert debugging information, if possible. This is not the default because only certain debugging formats are supported, and the conversion process can be time consuming. @item --gap-fill @var{val} Fill gaps between sections with @var{val}. This operation applies to the @emph{load address} (LMA) of the sections. It is done by increasing the size of the section with the lower address, and filling in the extra space created with @var{val}. @item --pad-to @var{address} Pad the output file up to the load address @var{address}. This is done by increasing the size of the last section. The extra space is filled in with the value specified by @option{--gap-fill} (default zero). @item --set-start @var{val} Set the start address of the new file to @var{val}. Not all object file formats support setting the start address. @item --change-start @var{incr} @itemx --adjust-start @var{incr} @cindex changing start address Change the start address by adding @var{incr}. Not all object file formats support setting the start address. @item --change-addresses @var{incr} @itemx --adjust-vma @var{incr} @cindex changing object addresses Change the VMA and LMA addresses of all sections, as well as the start address, by adding @var{incr}. Some object file formats do not permit section addresses to be changed arbitrarily. Note that this does not relocate the sections; if the program expects sections to be loaded at a certain address, and this option is used to change the sections such that they are loaded at a different address, the program may fail. @item --change-section-address @var{section}@{=,+,-@}@var{val} @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val} @cindex changing section address Set or change both the VMA address and the LMA address of the named @var{section}. If @samp{=} is used, the section address is set to @var{val}. Otherwise, @var{val} is added to or subtracted from the section address. See the comments under @option{--change-addresses}, above. If @var{section} does not exist in the input file, a warning will be issued, unless @option{--no-change-warnings} is used. @item --change-section-lma @var{section}@{=,+,-@}@var{val} @cindex changing section LMA Set or change the LMA address of the named @var{section}. The LMA address is the address where the section will be loaded into memory at program load time. Normally this is the same as the VMA address, which is the address of the section at program run time, but on some systems, especially those where a program is held in ROM, the two can be different. If @samp{=} is used, the section address is set to @var{val}. Otherwise, @var{val} is added to or subtracted from the section address. See the comments under @option{--change-addresses}, above. If @var{section} does not exist in the input file, a warning will be issued, unless @option{--no-change-warnings} is used. @item --change-section-vma @var{section}@{=,+,-@}@var{val} @cindex changing section VMA Set or change the VMA address of the named @var{section}. The VMA address is the address where the section will be located once the program has started executing. Normally this is the same as the LMA address, which is the address where the section will be loaded into memory, but on some systems, especially those where a program is held in ROM, the two can be different. If @samp{=} is used, the section address is set to @var{val}. Otherwise, @var{val} is added to or subtracted from the section address. See the comments under @option{--change-addresses}, above. If @var{section} does not exist in the input file, a warning will be issued, unless @option{--no-change-warnings} is used. @item --change-warnings @itemx --adjust-warnings If @option{--change-section-address} or @option{--change-section-lma} or @option{--change-section-vma} is used, and the named section does not exist, issue a warning. This is the default. @item --no-change-warnings @itemx --no-adjust-warnings Do not issue a warning if @option{--change-section-address} or @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even if the named section does not exist. @item --set-section-flags @var{section}=@var{flags} Set the flags for the named section. The @var{flags} argument is a comma separated string of flag names. The recognized names are @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and @samp{debug}. You can set the @samp{contents} flag for a section which does not have contents, but it is not meaningful to clear the @samp{contents} flag of a section which does have contents--just remove the section instead. Not all flags are meaningful for all object file formats. @item --add-section @var{sectionname}=@var{filename} Add a new section named @var{sectionname} while copying the file. The contents of the new section are taken from the file @var{filename}. The size of the section will be the size of the file. This option only works on file formats which can support sections with arbitrary names. @item --rename-section @var{oldname}=@var{newname}[,@var{flags}] Rename a section from @var{oldname} to @var{newname}, optionally changing the section's flags to @var{flags} in the process. This has the advantage over usng a linker script to perform the rename in that the output stays as an object file and does not become a linked executable. This option is particularly helpful when the input format is binary, since this will always create a section called .data. If for example, you wanted instead to create a section called .rodata containing binary data you could use the following command line to achieve it: @smallexample objcopy -I binary -O -B \ --rename-section .data=.rodata,alloc,load,readonly,data,contents \ @end smallexample @item --change-leading-char Some object file formats use special characters at the start of symbols. The most common such character is underscore, which compilers often add before every symbol. This option tells @command{objcopy} to change the leading character of every symbol when it converts between object file formats. If the object file formats use the same leading character, this option has no effect. Otherwise, it will add a character, or remove a character, or change a character, as appropriate. @item --remove-leading-char If the first character of a global symbol is a special symbol leading character used by the object file format, remove the character. The most common symbol leading character is underscore. This option will remove a leading underscore from all global symbols. This can be useful if you want to link together objects of different file formats with different conventions for symbol names. This is different from @option{--change-leading-char} because it always changes the symbol name when appropriate, regardless of the object file format of the output file. @item --srec-len=@var{ival} Meaningful only for srec output. Set the maximum length of the Srecords being produced to @var{ival}. This length covers both address, data and crc fields. @item --srec-forceS3 Meaningful only for srec output. Avoid generation of S1/S2 records, creating S3-only record format. @item --redefine-sym @var{old}=@var{new} Change the name of a symbol @var{old}, to @var{new}. This can be useful when one is trying link two things together for which you have no source, and there are name collisions. @item --redefine-syms=@var{filename} Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}" listed in the file @var{filename}. @var{filename} is simply a flat file, with one symbol pair per line. Line comments may be introduced by the hash character. This option may be given more than once. @item --weaken Change all global symbols in the file to be weak. This can be useful when building an object which will be linked against other objects using the @option{-R} option to the linker. This option is only effective when using an object file format which supports weak symbols. @item --keep-symbols=@var{filename} Apply @option{--keep-symbol} option to each symbol listed in the file @var{filename}. @var{filename} is simply a flat file, with one symbol name per line. Line comments may be introduced by the hash character. This option may be given more than once. @item --strip-symbols=@var{filename} Apply @option{--strip-symbol} option to each symbol listed in the file @var{filename}. @var{filename} is simply a flat file, with one symbol name per line. Line comments may be introduced by the hash character. This option may be given more than once. @item --strip-unneeded-symbols=@var{filename} Apply @option{--strip-unneeded-symbol} option to each symbol listed in the file @var{filename}. @var{filename} is simply a flat file, with one symbol name per line. Line comments may be introduced by the hash character. This option may be given more than once. @item --keep-global-symbols=@var{filename} Apply @option{--keep-global-symbol} option to each symbol listed in the file @var{filename}. @var{filename} is simply a flat file, with one symbol name per line. Line comments may be introduced by the hash character. This option may be given more than once. @item --localize-symbols=@var{filename} Apply @option{--localize-symbol} option to each symbol listed in the file @var{filename}. @var{filename} is simply a flat file, with one symbol name per line. Line comments may be introduced by the hash character. This option may be given more than once. @item --globalize-symbols=@var{filename} Apply @option{--globalize-symbol} option to each symbol listed in the file @var{filename}. @var{filename} is simply a flat file, with one symbol name per line. Line comments may be introduced by the hash character. This option may be given more than once. @item --weaken-symbols=@var{filename} Apply @option{--weaken-symbol} option to each symbol listed in the file @var{filename}. @var{filename} is simply a flat file, with one symbol name per line. Line comments may be introduced by the hash character. This option may be given more than once. @item --alt-machine-code=@var{index} If the output architecture has alternate machine codes, use the @var{index}th code instead of the default one. This is useful in case a machine is assigned an official code and the tool-chain adopts the new code, but other applications still depend on the original code being used. For ELF based architectures if the @var{index} alternative does not exist then the value is treated as an absolute number to be stored in the e_machine field of the ELF header. @item --writable-text Mark the output text as writable. This option isn't meaningful for all object file formats. @item --readonly-text Make the output text write protected. This option isn't meaningful for all object file formats. @item --pure Mark the output file as demand paged. This option isn't meaningful for all object file formats. @item --impure Mark the output file as impure. This option isn't meaningful for all object file formats. @item --prefix-symbols=@var{string} Prefix all symbols in the output file with @var{string}. @item --prefix-sections=@var{string} Prefix all section names in the output file with @var{string}. @item --prefix-alloc-sections=@var{string} Prefix all the names of all allocated sections in the output file with @var{string}. @item --add-gnu-debuglink=@var{path-to-file} Creates a .gnu_debuglink section which contains a reference to @var{path-to-file} and adds it to the output file. @item --keep-file-symbols When stripping a file, perhaps with @option{--strip-debug} or @option{--strip-unneeded}, retain any symbols specifying source file names, which would otherwise get stripped. @item --only-keep-debug Strip a file, removing contents of any sections that would not be stripped by @option{--strip-debug} and leaving the debugging sections intact. The intention is that this option will be used in conjunction with @option{--add-gnu-debuglink} to create a two part executable. One a stripped binary which will occupy less space in RAM and in a distribution and the second a debugging information file which is only needed if debugging abilities are required. The suggested procedure to create these files is as follows: @enumerate @item Link the executable as normal. Assuming that is is called @code{foo} then... @item Run @code{objcopy --only-keep-debug foo foo.dbg} to create a file containing the debugging info. @item Run @code{objcopy --strip-debug foo} to create a stripped executable. @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo} to add a link to the debugging info into the stripped executable. @end enumerate Note - the choice of @code{.dbg} as an extension for the debug info file is arbitrary. Also the @code{--only-keep-debug} step is optional. You could instead do this: @enumerate @item Link the executable as normal. @item Copy @code{foo} to @code{foo.full} @item Run @code{objcopy --strip-debug foo} @item Run @code{objcopy --add-gnu-debuglink=foo.full foo} @end enumerate i.e. the file pointed to by the @option{--add-gnu-debuglink} can be the full executable. It does not have to be a file created by the @option{--only-keep-debug} switch. @item -V @itemx --version Show the version number of @command{objcopy}. @item -v @itemx --verbose Verbose output: list all object files modified. In the case of archives, @samp{objcopy -V} lists all members of the archive. @item --help Show a summary of the options to @command{objcopy}. @item --info Display a list showing all architectures and object formats available. @end table @c man end @ignore @c man begin SEEALSO objcopy ld(1), objdump(1), and the Info entries for @file{binutils}. @c man end @end ignore @node objdump @chapter objdump @cindex object file information @kindex objdump @c man title objdump display information from object files. @smallexample @c man begin SYNOPSIS objdump objdump [@option{-a}|@option{--archive-headers}] [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}] [@option{-C}|@option{--demangle}[=@var{style}] ] [@option{-d}|@option{--disassemble}] [@option{-D}|@option{--disassemble-all}] [@option{-z}|@option{--disassemble-zeroes}] [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}] [@option{-f}|@option{--file-headers}] [@option{--file-start-context}] [@option{-g}|@option{--debugging}] [@option{-e}|@option{--debugging-tags}] [@option{-h}|@option{--section-headers}|@option{--headers}] [@option{-i}|@option{--info}] [@option{-j} @var{section}|@option{--section=}@var{section}] [@option{-l}|@option{--line-numbers}] [@option{-S}|@option{--source}] [@option{-m} @var{machine}|@option{--architecture=}@var{machine}] [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}] [@option{-p}|@option{--private-headers}] [@option{-r}|@option{--reloc}] [@option{-R}|@option{--dynamic-reloc}] [@option{-s}|@option{--full-contents}] [@option{-W}|@option{--dwarf}] [@option{-G}|@option{--stabs}] [@option{-t}|@option{--syms}] [@option{-T}|@option{--dynamic-syms}] [@option{-x}|@option{--all-headers}] [@option{-w}|@option{--wide}] [@option{--start-address=}@var{address}] [@option{--stop-address=}@var{address}] [@option{--prefix-addresses}] [@option{--[no-]show-raw-insn}] [@option{--adjust-vma=}@var{offset}] [@option{--special-syms}] [@option{-V}|@option{--version}] [@option{-H}|@option{--help}] @var{objfile}@dots{} @c man end @end smallexample @c man begin DESCRIPTION objdump @command{objdump} displays information about one or more object files. The options control what particular information to display. This information is mostly useful to programmers who are working on the compilation tools, as opposed to programmers who just want their program to compile and work. @var{objfile}@dots{} are the object files to be examined. When you specify archives, @command{objdump} shows information on each of the member object files. @c man end @c man begin OPTIONS objdump The long and short forms of options, shown here as alternatives, are equivalent. At least one option from the list @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-r,-R,-s,-S,-t,-T,-V,-x} must be given. @table @env @item -a @itemx --archive-header @cindex archive headers If any of the @var{objfile} files are archives, display the archive header information (in a format similar to @samp{ls -l}). Besides the information you could list with @samp{ar tv}, @samp{objdump -a} shows the object file format of each archive member. @item --adjust-vma=@var{offset} @cindex section addresses in objdump @cindex VMA in objdump When dumping information, first add @var{offset} to all the section addresses. This is useful if the section addresses do not correspond to the symbol table, which can happen when putting sections at particular addresses when using a format which can not represent section addresses, such as a.out. @item -b @var{bfdname} @itemx --target=@var{bfdname} @cindex object code format Specify that the object-code format for the object files is @var{bfdname}. This option may not be necessary; @var{objdump} can automatically recognize many formats. For example, @example objdump -b oasys -m vax -h fu.o @end example @noindent displays summary information from the section headers (@option{-h}) of @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object file in the format produced by Oasys compilers. You can list the formats available with the @option{-i} option. @xref{Target Selection}, for more information. @item -C @itemx --demangle[=@var{style}] @cindex demangling in objdump Decode (@dfn{demangle}) low-level symbol names into user-level names. Besides removing any initial underscore prepended by the system, this makes C++ function names readable. Different compilers have different mangling styles. The optional demangling style argument can be used to choose an appropriate demangling style for your compiler. @xref{c++filt}, for more information on demangling. @item -g @itemx --debugging Display debugging information. This attempts to parse debugging information stored in the file and print it out using a C like syntax. Only certain types of debugging information have been implemented. Some other types are supported by @command{readelf -w}. @xref{readelf}. @item -e @itemx --debugging-tags Like @option{-g}, but the information is generated in a format compatible with ctags tool. @item -d @itemx --disassemble @cindex disassembling object code @cindex machine instructions Display the assembler mnemonics for the machine instructions from @var{objfile}. This option only disassembles those sections which are expected to contain instructions. @item -D @itemx --disassemble-all Like @option{-d}, but disassemble the contents of all sections, not just those expected to contain instructions. @item --prefix-addresses When disassembling, print the complete address on each line. This is the older disassembly format. @item -EB @itemx -EL @itemx --endian=@{big|little@} @cindex endianness @cindex disassembly endianness Specify the endianness of the object files. This only affects disassembly. This can be useful when disassembling a file format which does not describe endianness information, such as S-records. @item -f @itemx --file-headers @cindex object file header Display summary information from the overall header of each of the @var{objfile} files. @item --file-start-context @cindex source code context Specify that when displaying interlisted source code/disassembly (assumes @option{-S}) from a file that has not yet been displayed, extend the context to the start of the file. @item -h @itemx --section-headers @itemx --headers @cindex section headers Display summary information from the section headers of the object file. File segments may be relocated to nonstandard addresses, for example by using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to @command{ld}. However, some object file formats, such as a.out, do not store the starting address of the file segments. In those situations, although @command{ld} relocates the sections correctly, using @samp{objdump -h} to list the file section headers cannot show the correct addresses. Instead, it shows the usual addresses, which are implicit for the target. @item -H @itemx --help Print a summary of the options to @command{objdump} and exit. @item -i @itemx --info @cindex architectures available @cindex object formats available Display a list showing all architectures and object formats available for specification with @option{-b} or @option{-m}. @item -j @var{name} @itemx --section=@var{name} @cindex section information Display information only for section @var{name}. @item -l @itemx --line-numbers @cindex source filenames for object files Label the display (using debugging information) with the filename and source line numbers corresponding to the object code or relocs shown. Only useful with @option{-d}, @option{-D}, or @option{-r}. @item -m @var{machine} @itemx --architecture=@var{machine} @cindex architecture @cindex disassembly architecture Specify the architecture to use when disassembling object files. This can be useful when disassembling object files which do not describe architecture information, such as S-records. You can list the available architectures with the @option{-i} option. @item -M @var{options} @itemx --disassembler-options=@var{options} Pass target specific information to the disassembler. Only supported on some targets. If it is necessary to specify more than one disassembler option then multiple @option{-M} options can be used or can be placed together into a comma separated list. If the target is an ARM architecture then this switch can be used to select which register name set is used during disassembler. Specifying @option{-M reg-names-std} (the default) will select the register names as used in ARM's instruction set documentation, but with register 13 called 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying @option{-M reg-names-apcs} will select the name set used by the ARM Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will just use @samp{r} followed by the register number. There are also two variants on the APCS register naming scheme enabled by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which use the ARM/Thumb Procedure Call Standard naming conventions. (Either with the normal register names or the special register names). This option can also be used for ARM architectures to force the disassembler to interpret all instructions as Thumb instructions by using the switch @option{--disassembler-options=force-thumb}. This can be useful when attempting to disassemble thumb code produced by other compilers. For the x86, some of the options duplicate functions of the @option{-m} switch, but allow finer grained control. Multiple selections from the following may be specified as a comma separated string. @option{x86-64}, @option{i386} and @option{i8086} select disassembly for the given architecture. @option{intel} and @option{att} select between intel syntax mode and AT&T syntax mode. @option{addr32}, @option{addr16}, @option{data32} and @option{data16} specify the default address size and operand size. These four options will be overridden if @option{x86-64}, @option{i386} or @option{i8086} appear later in the option string. Lastly, @option{suffix}, when in AT&T mode, instructs the disassembler to print a mnemonic suffix even when the suffix could be inferred by the operands. For PPC, @option{booke}, @option{booke32} and @option{booke64} select disassembly of BookE instructions. @option{32} and @option{64} select PowerPC and PowerPC64 disassembly, respectively. @option{e300} selects disassembly for the e300 family. For MIPS, this option controls the printing of instruction mneumonic names and register names in disassembled instructions. Multiple selections from the following may be specified as a comma separated string, and invalid options are ignored: @table @code @item no-aliases Print the 'raw' instruction mneumonic instead of some pseudo instruction mneumonic. I.E. print 'daddu' or 'or' instead of 'move', 'sll' instead of 'nop', etc. @item gpr-names=@var{ABI} Print GPR (general-purpose register) names as appropriate for the specified ABI. By default, GPR names are selected according to the ABI of the binary being disassembled. @item fpr-names=@var{ABI} Print FPR (floating-point register) names as appropriate for the specified ABI. By default, FPR numbers are printed rather than names. @item cp0-names=@var{ARCH} Print CP0 (system control coprocessor; coprocessor 0) register names as appropriate for the CPU or architecture specified by @var{ARCH}. By default, CP0 register names are selected according to the architecture and CPU of the binary being disassembled. @item hwr-names=@var{ARCH} Print HWR (hardware register, used by the @code{rdhwr} instruction) names as appropriate for the CPU or architecture specified by @var{ARCH}. By default, HWR names are selected according to the architecture and CPU of the binary being disassembled. @item reg-names=@var{ABI} Print GPR and FPR names as appropriate for the selected ABI. @item reg-names=@var{ARCH} Print CPU-specific register names (CP0 register and HWR names) as appropriate for the selected CPU or architecture. @end table For any of the options listed above, @var{ABI} or @var{ARCH} may be specified as @samp{numeric} to have numbers printed rather than names, for the selected types of registers. You can list the available values of @var{ABI} and @var{ARCH} using the @option{--help} option. For VAX, you can specify function entry addresses with @option{-M entry:0xf00ba}. You can use this multiple times to properly disassemble VAX binary files that don't contain symbol tables (like ROM dumps). In these cases, the function entry mask would otherwise be decoded as VAX instructions, which would probably lead the the rest of the function being wrongly disassembled. @item -p @itemx --private-headers Print information that is specific to the object file format. The exact information printed depends upon the object file format. For some object file formats, no additional information is printed. @item -r @itemx --reloc @cindex relocation entries, in object file Print the relocation entries of the file. If used with @option{-d} or @option{-D}, the relocations are printed interspersed with the disassembly. @item -R @itemx --dynamic-reloc @cindex dynamic relocation entries, in object file Print the dynamic relocation entries of the file. This is only meaningful for dynamic objects, such as certain types of shared libraries. @item -s @itemx --full-contents @cindex sections, full contents @cindex object file sections Display the full contents of any sections requested. By default all non-empty sections are displayed. @item -S @itemx --source @cindex source disassembly @cindex disassembly, with source Display source code intermixed with disassembly, if possible. Implies @option{-d}. @item --show-raw-insn When disassembling instructions, print the instruction in hex as well as in symbolic form. This is the default except when @option{--prefix-addresses} is used. @item --no-show-raw-insn When disassembling instructions, do not print the instruction bytes. This is the default when @option{--prefix-addresses} is used. @item -W @itemx --dwarf @cindex DWARF @cindex debug symbols Displays the contents of the DWARF debug sections in the file, if any are present. @item -G @itemx --stabs @cindex stab @cindex .stab @cindex debug symbols @cindex ELF object file format Display the full contents of any sections requested. Display the contents of the .stab and .stab.index and .stab.excl sections from an ELF file. This is only useful on systems (such as Solaris 2.0) in which @code{.stab} debugging symbol-table entries are carried in an ELF section. In most other file formats, debugging symbol-table entries are interleaved with linkage symbols, and are visible in the @option{--syms} output. @ifclear man For more information on stabs symbols, see @ref{Top,Stabs,Stabs Overview,stabs.info, The ``stabs'' debug format}. @end ifclear @item --start-address=@var{address} @cindex start-address Start displaying data at the specified address. This affects the output of the @option{-d}, @option{-r} and @option{-s} options. @item --stop-address=@var{address} @cindex stop-address Stop displaying data at the specified address. This affects the output of the @option{-d}, @option{-r} and @option{-s} options. @item -t @itemx --syms @cindex symbol table entries, printing Print the symbol table entries of the file. This is similar to the information provided by the @samp{nm} program. @item -T @itemx --dynamic-syms @cindex dynamic symbol table entries, printing Print the dynamic symbol table entries of the file. This is only meaningful for dynamic objects, such as certain types of shared libraries. This is similar to the information provided by the @samp{nm} program when given the @option{-D} (@option{--dynamic}) option. @item --special-syms When displaying symbols include those which the target considers to be special in some way and which would not normally be of interest to the user. @item -V @itemx --version Print the version number of @command{objdump} and exit. @item -x @itemx --all-headers @cindex all header information, object file @cindex header information, all Display all available header information, including the symbol table and relocation entries. Using @option{-x} is equivalent to specifying all of @option{-a -f -h -p -r -t}. @item -w @itemx --wide @cindex wide output, printing Format some lines for output devices that have more than 80 columns. Also do not truncate symbol names when they are displayed. @item -z @itemx --disassemble-zeroes Normally the disassembly output will skip blocks of zeroes. This option directs the disassembler to disassemble those blocks, just like any other data. @end table @c man end @ignore @c man begin SEEALSO objdump nm(1), readelf(1), and the Info entries for @file{binutils}. @c man end @end ignore @node ranlib @chapter ranlib @kindex ranlib @cindex archive contents @cindex symbol index @c man title ranlib generate index to archive. @smallexample @c man begin SYNOPSIS ranlib ranlib [@option{-vV}] @var{archive} @c man end @end smallexample @c man begin DESCRIPTION ranlib @command{ranlib} generates an index to the contents of an archive and stores it in the archive. The index lists each symbol defined by a member of an archive that is a relocatable object file. You may use @samp{nm -s} or @samp{nm --print-armap} to list this index. An archive with such an index speeds up linking to the library and allows routines in the library to call each other without regard to their placement in the archive. The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running @command{ranlib} is completely equivalent to executing @samp{ar -s}. @xref{ar}. @c man end @c man begin OPTIONS ranlib @table @env @item -v @itemx -V @itemx --version Show the version number of @command{ranlib}. @end table @c man end @ignore @c man begin SEEALSO ranlib ar(1), nm(1), and the Info entries for @file{binutils}. @c man end @end ignore @node size @chapter size @kindex size @cindex section sizes @c man title size list section sizes and total size. @smallexample @c man begin SYNOPSIS size size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}] [@option{--help}] [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}] [@option{-t}|@option{--totals}] [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}] [@var{objfile}@dots{}] @c man end @end smallexample @c man begin DESCRIPTION size The @sc{gnu} @command{size} utility lists the section sizes---and the total size---for each of the object or archive files @var{objfile} in its argument list. By default, one line of output is generated for each object file or each module in an archive. @var{objfile}@dots{} are the object files to be examined. If none are specified, the file @code{a.out} will be used. @c man end @c man begin OPTIONS size The command line options have the following meanings: @table @env @item -A @itemx -B @itemx --format=@var{compatibility} @cindex @command{size} display format Using one of these options, you can choose whether the output from @sc{gnu} @command{size} resembles output from System V @command{size} (using @option{-A}, or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or @option{--format=berkeley}). The default is the one-line format similar to Berkeley's. @c Bonus for doc-source readers: you can also say --format=strange (or @c anything else that starts with 's') for sysv, and --format=boring (or @c anything else that starts with 'b') for Berkeley. Here is an example of the Berkeley (default) format of output from @command{size}: @smallexample $ size --format=Berkeley ranlib size text data bss dec hex filename 294880 81920 11592 388392 5ed28 ranlib 294880 81920 11888 388688 5ee50 size @end smallexample @noindent This is the same data, but displayed closer to System V conventions: @smallexample $ size --format=SysV ranlib size ranlib : section size addr .text 294880 8192 .data 81920 303104 .bss 11592 385024 Total 388392 size : section size addr .text 294880 8192 .data 81920 303104 .bss 11888 385024 Total 388688 @end smallexample @item --help Show a summary of acceptable arguments and options. @item -d @itemx -o @itemx -x @itemx --radix=@var{number} @cindex @command{size} number format @cindex radix for section sizes Using one of these options, you can control whether the size of each section is given in decimal (@option{-d}, or @option{--radix=10}); octal (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or @option{--radix=16}). In @option{--radix=@var{number}}, only the three values (8, 10, 16) are supported. The total size is always given in two radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or octal and hexadecimal if you're using @option{-o}. @item -t @itemx --totals Show totals of all objects listed (Berkeley format listing mode only). @item --target=@var{bfdname} @cindex object code format Specify that the object-code format for @var{objfile} is @var{bfdname}. This option may not be necessary; @command{size} can automatically recognize many formats. @xref{Target Selection}, for more information. @item -V @itemx --version Display the version number of @command{size}. @end table @c man end @ignore @c man begin SEEALSO size ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}. @c man end @end ignore @node strings @chapter strings @kindex strings @cindex listings strings @cindex printing strings @cindex strings, printing @c man title strings print the strings of printable characters in files. @smallexample @c man begin SYNOPSIS strings strings [@option{-afov}] [@option{-}@var{min-len}] [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}] [@option{-t} @var{radix}] [@option{--radix=}@var{radix}] [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}] [@option{-}] [@option{--all}] [@option{--print-file-name}] [@option{--target=}@var{bfdname}] [@option{--help}] [@option{--version}] @var{file}@dots{} @c man end @end smallexample @c man begin DESCRIPTION strings For each @var{file} given, @sc{gnu} @command{strings} prints the printable character sequences that are at least 4 characters long (or the number given with the options below) and are followed by an unprintable character. By default, it only prints the strings from the initialized and loaded sections of object files; for other types of files, it prints the strings from the whole file. @command{strings} is mainly useful for determining the contents of non-text files. @c man end @c man begin OPTIONS strings @table @env @item -a @itemx --all @itemx - Do not scan only the initialized and loaded sections of object files; scan the whole files. @item -f @itemx --print-file-name Print the name of the file before each string. @item --help Print a summary of the program usage on the standard output and exit. @item -@var{min-len} @itemx -n @var{min-len} @itemx --bytes=@var{min-len} Print sequences of characters that are at least @var{min-len} characters long, instead of the default 4. @item -o Like @samp{-t o}. Some other versions of @command{strings} have @option{-o} act like @samp{-t d} instead. Since we can not be compatible with both ways, we simply chose one. @item -t @var{radix} @itemx --radix=@var{radix} Print the offset within the file before each string. The single character argument specifies the radix of the offset---@samp{o} for octal, @samp{x} for hexadecimal, or @samp{d} for decimal. @item -e @var{encoding} @itemx --encoding=@var{encoding} Select the character encoding of the strings that are to be found. Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte characters (ASCII, ISO 8859, etc., default), @samp{S} = single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} = 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit littleendian. Useful for finding wide character strings. @item --target=@var{bfdname} @cindex object code format Specify an object code format other than your system's default format. @xref{Target Selection}, for more information. @item -v @itemx --version Print the program version number on the standard output and exit. @end table @c man end @ignore @c man begin SEEALSO strings ar(1), nm(1), objdump(1), ranlib(1), readelf(1) and the Info entries for @file{binutils}. @c man end @end ignore @node strip @chapter strip @kindex strip @cindex removing symbols @cindex discarding symbols @cindex symbols, discarding @c man title strip Discard symbols from object files. @smallexample @c man begin SYNOPSIS strip strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}] [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}] [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}] [@option{-s}|@option{--strip-all}] [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}] [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}] [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}] [@option{-w}|@option{--wildcard}] [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}] [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}] [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}] [@option{--keep-file-symbols}] [@option{--only-keep-debug}] [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}] [@option{--help}] [@option{--info}] @var{objfile}@dots{} @c man end @end smallexample @c man begin DESCRIPTION strip @sc{gnu} @command{strip} discards all symbols from object files @var{objfile}. The list of object files may include archives. At least one object file must be given. @command{strip} modifies the files named in its argument, rather than writing modified copies under different names. @c man end @c man begin OPTIONS strip @table @env @item -F @var{bfdname} @itemx --target=@var{bfdname} Treat the original @var{objfile} as a file with the object code format @var{bfdname}, and rewrite it in the same format. @xref{Target Selection}, for more information. @item --help Show a summary of the options to @command{strip} and exit. @item --info Display a list showing all architectures and object formats available. @item -I @var{bfdname} @itemx --input-target=@var{bfdname} Treat the original @var{objfile} as a file with the object code format @var{bfdname}. @xref{Target Selection}, for more information. @item -O @var{bfdname} @itemx --output-target=@var{bfdname} Replace @var{objfile} with a file in the output format @var{bfdname}. @xref{Target Selection}, for more information. @item -R @var{sectionname} @itemx --remove-section=@var{sectionname} Remove any section named @var{sectionname} from the output file. This option may be given more than once. Note that using this option inappropriately may make the output file unusable. @item -s @itemx --strip-all Remove all symbols. @item -g @itemx -S @itemx -d @itemx --strip-debug Remove debugging symbols only. @item --strip-unneeded Remove all symbols that are not needed for relocation processing. @item -K @var{symbolname} @itemx --keep-symbol=@var{symbolname} When stripping symbols, keep symbol @var{symbolname} even if it would normally be stripped. This option may be given more than once. @item -N @var{symbolname} @itemx --strip-symbol=@var{symbolname} Remove symbol @var{symbolname} from the source file. This option may be given more than once, and may be combined with strip options other than @option{-K}. @item -o @var{file} Put the stripped output in @var{file}, rather than replacing the existing file. When this argument is used, only one @var{objfile} argument may be specified. @item -p @itemx --preserve-dates Preserve the access and modification dates of the file. @item -w @itemx --wildcard Permit regular expressions in @var{symbolname}s used in other command line options. The question mark (?), asterisk (*), backslash (\) and square brackets ([]) operators can be used anywhere in the symbol name. If the first character of the symbol name is the exclamation point (!) then the sense of the switch is reversed for that symbol. For example: @smallexample -w -K !foo -K fo* @end smallexample would cause strip to only keep symbols that start with the letters ``fo'', but to discard the symbol ``foo''. @item -x @itemx --discard-all Remove non-global symbols. @item -X @itemx --discard-locals Remove compiler-generated local symbols. (These usually start with @samp{L} or @samp{.}.) @item --keep-file-symbols When stripping a file, perhaps with @option{--strip-debug} or @option{--strip-unneeded}, retain any symbols specifying source file names, which would otherwise get stripped. @item --only-keep-debug Strip a file, removing any sections that would be stripped by @option{--strip-debug} and leaving the debugging sections. The intention is that this option will be used in conjunction with @option{--add-gnu-debuglink} to create a two part executable. One a stripped binary which will occupy less space in RAM and in a distribution and the second a debugging information file which is only needed if debugging abilities are required. The suggested procedure to create these files is as follows: @enumerate @item Link the executable as normal. Assuming that is is called @code{foo} then... @item Run @code{objcopy --only-keep-debug foo foo.dbg} to create a file containing the debugging info. @item Run @code{objcopy --strip-debug foo} to create a stripped executable. @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo} to add a link to the debugging info into the stripped executable. @end enumerate Note - the choice of @code{.dbg} as an extension for the debug info file is arbitrary. Also the @code{--only-keep-debug} step is optional. You could instead do this: @enumerate @item Link the executable as normal. @item Copy @code{foo} to @code{foo.full} @item Run @code{strip --strip-debug foo} @item Run @code{objcopy --add-gnu-debuglink=foo.full foo} @end enumerate ie the file pointed to by the @option{--add-gnu-debuglink} can be the full executable. It does not have to be a file created by the @option{--only-keep-debug} switch. @item -V @itemx --version Show the version number for @command{strip}. @item -v @itemx --verbose Verbose output: list all object files modified. In the case of archives, @samp{strip -v} lists all members of the archive. @end table @c man end @ignore @c man begin SEEALSO strip the Info entries for @file{binutils}. @c man end @end ignore @node c++filt, addr2line, strip, Top @chapter c++filt @kindex c++filt @cindex demangling C++ symbols @c man title cxxfilt Demangle C++ and Java symbols. @smallexample @c man begin SYNOPSIS cxxfilt c++filt [@option{-_}|@option{--strip-underscores}] [@option{-n}|@option{--no-strip-underscores}] [@option{-p}|@option{--no-params}] [@option{-t}|@option{--types}] [@option{-i}|@option{--no-verbose}] [@option{-s} @var{format}|@option{--format=}@var{format}] [@option{--help}] [@option{--version}] [@var{symbol}@dots{}] @c man end @end smallexample @c man begin DESCRIPTION cxxfilt @kindex cxxfilt The C++ and Java languages provide function overloading, which means that you can write many functions with the same name, providing that each function takes parameters of different types. In order to be able to distinguish these similarly named functions C++ and Java encode them into a low-level assembler name which uniquely identifies each different version. This process is known as @dfn{mangling}. The @command{c++filt} @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on MS-DOS this program is named @command{CXXFILT}.} program does the inverse mapping: it decodes (@dfn{demangles}) low-level names into user-level names so that they can be read. Every alphanumeric word (consisting of letters, digits, underscores, dollars, or periods) seen in the input is a potential mangled name. If the name decodes into a C++ name, the C++ name replaces the low-level name in the output, otherwise the original word is output. In this way you can pass an entire assembler source file, containing mangled names, through @command{c++filt} and see the same source file containing demangled names. You can also use @command{c++filt} to decipher individual symbols by passing them on the command line: @example c++filt @var{symbol} @end example If no @var{symbol} arguments are given, @command{c++filt} reads symbol names from the standard input instead. All the results are printed on the standard output. The difference between reading names from the command line versus reading names from the standard input is that command line arguments are expected to be just mangled names and no checking is performed to seperate them from surrounding text. Thus for example: @smallexample c++filt -n _Z1fv @end smallexample will work and demangle the name to ``f()'' whereas: @smallexample c++filt -n _Z1fv, @end smallexample will not work. (Note the extra comma at the end of the mangled name which makes it invalid). This command however will work: @smallexample echo _Z1fv, | c++filt -n @end smallexample and will display ``f(),'' ie the demangled name followed by a trailing comma. This behaviour is because when the names are read from the standard input it is expected that they might be part of an assembler source file where there might be extra, extraneous characters trailing after a mangled name. eg: @smallexample .type _Z1fv, @@function @end smallexample @c man end @c man begin OPTIONS cxxfilt @table @env @item -_ @itemx --strip-underscores On some systems, both the C and C++ compilers put an underscore in front of every name. For example, the C name @code{foo} gets the low-level name @code{_foo}. This option removes the initial underscore. Whether @command{c++filt} removes the underscore by default is target dependent. @item -j @itemx --java Prints demangled names using Java syntax. The default is to use C++ syntax. @item -n @itemx --no-strip-underscores Do not remove the initial underscore. @item -p @itemx --no-params When demangling the name of a function, do not display the types of the function's parameters. @item -t @itemx --types Attempt to demangle types as well as function names. This is disabled by default since mangled types are normally only used internally in the compiler, and they can be confused with non-mangled names. eg a function called ``a'' treated as a mangled type name would be demangled to ``signed char''. @item -i @itemx --no-verbose Do not include implementation details (if any) in the demangled output. @item -s @var{format} @itemx --format=@var{format} @command{c++filt} can decode various methods of mangling, used by different compilers. The argument to this option selects which method it uses: @table @code @item auto Automatic selection based on executable (the default method) @item gnu the one used by the @sc{gnu} C++ compiler (g++) @item lucid the one used by the Lucid compiler (lcc) @item arm the one specified by the C++ Annotated Reference Manual @item hp the one used by the HP compiler (aCC) @item edg the one used by the EDG compiler @item gnu-v3 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI. @item java the one used by the @sc{gnu} Java compiler (gcj) @item gnat the one used by the @sc{gnu} Ada compiler (GNAT). @end table @item --help Print a summary of the options to @command{c++filt} and exit. @item --version Print the version number of @command{c++filt} and exit. @end table @c man end @ignore @c man begin SEEALSO cxxfilt the Info entries for @file{binutils}. @c man end @end ignore @quotation @emph{Warning:} @command{c++filt} is a new utility, and the details of its user interface are subject to change in future releases. In particular, a command-line option may be required in the the future to decode a name passed as an argument on the command line; in other words, @example c++filt @var{symbol} @end example @noindent may in a future release become @example c++filt @var{option} @var{symbol} @end example @end quotation @node addr2line @chapter addr2line @kindex addr2line @cindex address to file name and line number @c man title addr2line convert addresses into file names and line numbers. @smallexample @c man begin SYNOPSIS addr2line addr2line [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}] [@option{-C}|@option{--demangle}[=@var{style}]] [@option{-e} @var{filename}|@option{--exe=}@var{filename}] [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}] [@option{-i}|@option{--inlines}] [@option{-j}|@option{--section=}@var{name}] [@option{-H}|@option{--help}] [@option{-V}|@option{--version}] [addr addr @dots{}] @c man end @end smallexample @c man begin DESCRIPTION addr2line @command{addr2line} translates addresses into file names and line numbers. Given an address in an executable or an offset in a section of a relocatable object, it uses the debugging information to figure out which file name and line number are associated with it. The executable or relocatable object to use is specified with the @option{-e} option. The default is the file @file{a.out}. The section in the relocatable object to use is specified with the @option{-j} option. @command{addr2line} has two modes of operation. In the first, hexadecimal addresses are specified on the command line, and @command{addr2line} displays the file name and line number for each address. In the second, @command{addr2line} reads hexadecimal addresses from standard input, and prints the file name and line number for each address on standard output. In this mode, @command{addr2line} may be used in a pipe to convert dynamically chosen addresses. The format of the output is @samp{FILENAME:LINENO}. The file name and line number for each address is printed on a separate line. If the @command{-f} option is used, then each @samp{FILENAME:LINENO} line is preceded by a @samp{FUNCTIONNAME} line which is the name of the function containing the address. If the file name or function name can not be determined, @command{addr2line} will print two question marks in their place. If the line number can not be determined, @command{addr2line} will print 0. @c man end @c man begin OPTIONS addr2line The long and short forms of options, shown here as alternatives, are equivalent. @table @env @item -b @var{bfdname} @itemx --target=@var{bfdname} @cindex object code format Specify that the object-code format for the object files is @var{bfdname}. @item -C @itemx --demangle[=@var{style}] @cindex demangling in objdump Decode (@dfn{demangle}) low-level symbol names into user-level names. Besides removing any initial underscore prepended by the system, this makes C++ function names readable. Different compilers have different mangling styles. The optional demangling style argument can be used to choose an appropriate demangling style for your compiler. @xref{c++filt}, for more information on demangling. @item -e @var{filename} @itemx --exe=@var{filename} Specify the name of the executable for which addresses should be translated. The default file is @file{a.out}. @item -f @itemx --functions Display function names as well as file and line number information. @item -s @itemx --basenames Display only the base of each file name. @item -i @itemx --inlines If the address belongs to a function that was inlined, the source information for all enclosing scopes back to the first non-inlined function will also be printed. For example, if @code{main} inlines @code{callee1} which inlines @code{callee2}, and address is from @code{callee2}, the source information for @code{callee1} and @code{main} will also be printed. @item -j @itemx --section Read offsets relative to the specified section instead of absolute addresses. @end table @c man end @ignore @c man begin SEEALSO addr2line Info entries for @file{binutils}. @c man end @end ignore @node nlmconv @chapter nlmconv @command{nlmconv} converts a relocatable object file into a NetWare Loadable Module. @ignore @command{nlmconv} currently works with @samp{i386} object files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC} object files in @sc{elf}, or @code{a.out} format@footnote{ @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object format in the Binary File Descriptor library. It has only been tested with the above formats.}. @end ignore @quotation @emph{Warning:} @command{nlmconv} is not always built as part of the binary utilities, since it is only useful for NLM targets. @end quotation @c man title nlmconv converts object code into an NLM. @smallexample @c man begin SYNOPSIS nlmconv nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}] [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}] [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}] [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}] [@option{-h}|@option{--help}] [@option{-V}|@option{--version}] @var{infile} @var{outfile} @c man end @end smallexample @c man begin DESCRIPTION nlmconv @command{nlmconv} converts the relocatable @samp{i386} object file @var{infile} into the NetWare Loadable Module @var{outfile}, optionally reading @var{headerfile} for NLM header information. For instructions on writing the NLM command file language used in header files, see the @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM Development and Tools Overview}, which is part of the NLM Software Developer's Kit (``NLM SDK''), available from Novell, Inc. @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read @var{infile}; @ifclear man see @ref{BFD,,BFD,ld.info,Using LD}, for more information. @end ifclear @command{nlmconv} can perform a link step. In other words, you can list more than one object file for input if you list them in the definitions file (rather than simply specifying one input file on the command line). In this case, @command{nlmconv} calls the linker for you. @c man end @c man begin OPTIONS nlmconv @table @env @item -I @var{bfdname} @itemx --input-target=@var{bfdname} Object format of the input file. @command{nlmconv} can usually determine the format of a given file (so no default is necessary). @xref{Target Selection}, for more information. @item -O @var{bfdname} @itemx --output-target=@var{bfdname} Object format of the output file. @command{nlmconv} infers the output format based on the input format, e.g. for a @samp{i386} input file the output format is @samp{nlm32-i386}. @xref{Target Selection}, for more information. @item -T @var{headerfile} @itemx --header-file=@var{headerfile} Reads @var{headerfile} for NLM header information. For instructions on writing the NLM command file language used in header files, see@ see the @samp{linkers} section, of the @cite{NLM Development and Tools Overview}, which is part of the NLM Software Developer's Kit, available from Novell, Inc. @item -d @itemx --debug Displays (on standard error) the linker command line used by @command{nlmconv}. @item -l @var{linker} @itemx --linker=@var{linker} Use @var{linker} for any linking. @var{linker} can be an absolute or a relative pathname. @item -h @itemx --help Prints a usage summary. @item -V @itemx --version Prints the version number for @command{nlmconv}. @end table @c man end @ignore @c man begin SEEALSO nlmconv the Info entries for @file{binutils}. @c man end @end ignore @node windres @chapter windres @command{windres} may be used to manipulate Windows resources. @quotation @emph{Warning:} @command{windres} is not always built as part of the binary utilities, since it is only useful for Windows targets. @end quotation @c man title windres manipulate Windows resources. @smallexample @c man begin SYNOPSIS windres windres [options] [input-file] [output-file] @c man end @end smallexample @c man begin DESCRIPTION windres @command{windres} reads resources from an input file and copies them into an output file. Either file may be in one of three formats: @table @code @item rc A text format read by the Resource Compiler. @item res A binary format generated by the Resource Compiler. @item coff A COFF object or executable. @end table The exact description of these different formats is available in documentation from Microsoft. When @command{windres} converts from the @code{rc} format to the @code{res} format, it is acting like the Windows Resource Compiler. When @command{windres} converts from the @code{res} format to the @code{coff} format, it is acting like the Windows @code{CVTRES} program. When @command{windres} generates an @code{rc} file, the output is similar but not identical to the format expected for the input. When an input @code{rc} file refers to an external filename, an output @code{rc} file will instead include the file contents. If the input or output format is not specified, @command{windres} will guess based on the file name, or, for the input file, the file contents. A file with an extension of @file{.rc} will be treated as an @code{rc} file, a file with an extension of @file{.res} will be treated as a @code{res} file, and a file with an extension of @file{.o} or @file{.exe} will be treated as a @code{coff} file. If no output file is specified, @command{windres} will print the resources in @code{rc} format to standard output. The normal use is for you to write an @code{rc} file, use @command{windres} to convert it to a COFF object file, and then link the COFF file into your application. This will make the resources described in the @code{rc} file available to Windows. @c man end @c man begin OPTIONS windres @table @env @item -i @var{filename} @itemx --input @var{filename} The name of the input file. If this option is not used, then @command{windres} will use the first non-option argument as the input file name. If there are no non-option arguments, then @command{windres} will read from standard input. @command{windres} can not read a COFF file from standard input. @item -o @var{filename} @itemx --output @var{filename} The name of the output file. If this option is not used, then @command{windres} will use the first non-option argument, after any used for the input file name, as the output file name. If there is no non-option argument, then @command{windres} will write to standard output. @command{windres} can not write a COFF file to standard output. Note, for compatability with @command{rc} the option @option{-fo} is also accepted, but its use is not recommended. @item -J @var{format} @itemx --input-format @var{format} The input format to read. @var{format} may be @samp{res}, @samp{rc}, or @samp{coff}. If no input format is specified, @command{windres} will guess, as described above. @item -O @var{format} @itemx --output-format @var{format} The output format to generate. @var{format} may be @samp{res}, @samp{rc}, or @samp{coff}. If no output format is specified, @command{windres} will guess, as described above. @item -F @var{target} @itemx --target @var{target} Specify the BFD format to use for a COFF file as input or output. This is a BFD target name; you can use the @option{--help} option to see a list of supported targets. Normally @command{windres} will use the default format, which is the first one listed by the @option{--help} option. @ifclear man @ref{Target Selection}. @end ifclear @item --preprocessor @var{program} When @command{windres} reads an @code{rc} file, it runs it through the C preprocessor first. This option may be used to specify the preprocessor to use, including any leading arguments. The default preprocessor argument is @code{gcc -E -xc-header -DRC_INVOKED}. @item -I @var{directory} @itemx --include-dir @var{directory} Specify an include directory to use when reading an @code{rc} file. @command{windres} will pass this to the preprocessor as an @option{-I} option. @command{windres} will also search this directory when looking for files named in the @code{rc} file. If the argument passed to this command matches any of the supported @var{formats} (as descrived in the @option{-J} option), it will issue a deprecation warning, and behave just like the @option{-J} option. New programs should not use this behaviour. If a directory happens to match a @var{format}, simple prefix it with @samp{./} to disable the backward compatibility. @item -D @var{target} @itemx --define @var{sym}[=@var{val}] Specify a @option{-D} option to pass to the preprocessor when reading an @code{rc} file. @item -U @var{target} @itemx --undefine @var{sym} Specify a @option{-U} option to pass to the preprocessor when reading an @code{rc} file. @item -r Ignored for compatibility with rc. @item -v Enable verbose mode. This tells you what the preprocessor is if you didn't specify one. @item -l @var{val} @item --language @var{val} Specify the default language to use when reading an @code{rc} file. @var{val} should be a hexadecimal language code. The low eight bits are the language, and the high eight bits are the sublanguage. @item --use-temp-file Use a temporary file to instead of using popen to read the output of the preprocessor. Use this option if the popen implementation is buggy on the host (eg., certain non-English language versions of Windows 95 and Windows 98 are known to have buggy popen where the output will instead go the console). @item --no-use-temp-file Use popen, not a temporary file, to read the output of the preprocessor. This is the default behaviour. @item -h @item --help Prints a usage summary. @item -V @item --version Prints the version number for @command{windres}. @item --yydebug If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1}, this will turn on parser debugging. @end table @c man end @ignore @c man begin SEEALSO windres the Info entries for @file{binutils}. @c man end @end ignore @node dlltool @chapter dlltool @cindex DLL @kindex dlltool @command{dlltool} is used to create the files needed to create dynamic link libraries (DLLs) on systems which understand PE format image files such as Windows. A DLL contains an export table which contains information that the runtime loader needs to resolve references from a referencing program. The export table is generated by this program by reading in a @file{.def} file or scanning the @file{.a} and @file{.o} files which will be in the DLL. A @file{.o} file can contain information in special @samp{.drectve} sections with export information. @quotation @emph{Note:} @command{dlltool} is not always built as part of the binary utilities, since it is only useful for those targets which support DLLs. @end quotation @c man title dlltool Create files needed to build and use DLLs. @smallexample @c man begin SYNOPSIS dlltool dlltool [@option{-d}|@option{--input-def} @var{def-file-name}] [@option{-b}|@option{--base-file} @var{base-file-name}] [@option{-e}|@option{--output-exp} @var{exports-file-name}] [@option{-z}|@option{--output-def} @var{def-file-name}] [@option{-l}|@option{--output-lib} @var{library-file-name}] [@option{--export-all-symbols}] [@option{--no-export-all-symbols}] [@option{--exclude-symbols} @var{list}] [@option{--no-default-excludes}] [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}] [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}] [@option{-a}|@option{--add-indirect}] [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}] [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}] [@option{-p}|@option{--ext-prefix-alias} @var{prefix}] [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}] [@option{-i}|@option{--interwork}] [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}] [@option{-v}|@option{--verbose}] [@option{-h}|@option{--help}] [@option{-V}|@option{--version}] [object-file @dots{}] @c man end @end smallexample @c man begin DESCRIPTION dlltool @command{dlltool} reads its inputs, which can come from the @option{-d} and @option{-b} options as well as object files specified on the command line. It then processes these inputs and if the @option{-e} option has been specified it creates a exports file. If the @option{-l} option has been specified it creates a library file and if the @option{-z} option has been specified it creates a def file. Any or all of the @option{-e}, @option{-l} and @option{-z} options can be present in one invocation of dlltool. When creating a DLL, along with the source for the DLL, it is necessary to have three other files. @command{dlltool} can help with the creation of these files. The first file is a @file{.def} file which specifies which functions are exported from the DLL, which functions the DLL imports, and so on. This is a text file and can be created by hand, or @command{dlltool} can be used to create it using the @option{-z} option. In this case @command{dlltool} will scan the object files specified on its command line looking for those functions which have been specially marked as being exported and put entries for them in the @file{.def} file it creates. In order to mark a function as being exported from a DLL, it needs to have an @option{-export:} entry in the @samp{.drectve} section of the object file. This can be done in C by using the asm() operator: @smallexample asm (".section .drectve"); asm (".ascii \"-export:my_func\""); int my_func (void) @{ @dots{} @} @end smallexample The second file needed for DLL creation is an exports file. This file is linked with the object files that make up the body of the DLL and it handles the interface between the DLL and the outside world. This is a binary file and it can be created by giving the @option{-e} option to @command{dlltool} when it is creating or reading in a @file{.def} file. The third file needed for DLL creation is the library file that programs will link with in order to access the functions in the DLL. This file can be created by giving the @option{-l} option to dlltool when it is creating or reading in a @file{.def} file. @command{dlltool} builds the library file by hand, but it builds the exports file by creating temporary files containing assembler statements and then assembling these. The @option{-S} command line option can be used to specify the path to the assembler that dlltool will use, and the @option{-f} option can be used to pass specific flags to that assembler. The @option{-n} can be used to prevent dlltool from deleting these temporary assembler files when it is done, and if @option{-n} is specified twice then this will prevent dlltool from deleting the temporary object files it used to build the library. Here is an example of creating a DLL from a source file @samp{dll.c} and also creating a program (from an object file called @samp{program.o}) that uses that DLL: @smallexample gcc -c dll.c dlltool -e exports.o -l dll.lib dll.o gcc dll.o exports.o -o dll.dll gcc program.o dll.lib -o program @end smallexample @c man end @c man begin OPTIONS dlltool The command line options have the following meanings: @table @env @item -d @var{filename} @itemx --input-def @var{filename} @cindex input .def file Specifies the name of a @file{.def} file to be read in and processed. @item -b @var{filename} @itemx --base-file @var{filename} @cindex base files Specifies the name of a base file to be read in and processed. The contents of this file will be added to the relocation section in the exports file generated by dlltool. @item -e @var{filename} @itemx --output-exp @var{filename} Specifies the name of the export file to be created by dlltool. @item -z @var{filename} @itemx --output-def @var{filename} Specifies the name of the @file{.def} file to be created by dlltool. @item -l @var{filename} @itemx --output-lib @var{filename} Specifies the name of the library file to be created by dlltool. @item --export-all-symbols Treat all global and weak defined symbols found in the input object files as symbols to be exported. There is a small list of symbols which are not exported by default; see the @option{--no-default-excludes} option. You may add to the list of symbols to not export by using the @option{--exclude-symbols} option. @item --no-export-all-symbols Only export symbols explicitly listed in an input @file{.def} file or in @samp{.drectve} sections in the input object files. This is the default behaviour. The @samp{.drectve} sections are created by @samp{dllexport} attributes in the source code. @item --exclude-symbols @var{list} Do not export the symbols in @var{list}. This is a list of symbol names separated by comma or colon characters. The symbol names should not contain a leading underscore. This is only meaningful when @option{--export-all-symbols} is used. @item --no-default-excludes When @option{--export-all-symbols} is used, it will by default avoid exporting certain special symbols. The current list of symbols to avoid exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0}, @samp{impure_ptr}. You may use the @option{--no-default-excludes} option to go ahead and export these special symbols. This is only meaningful when @option{--export-all-symbols} is used. @item -S @var{path} @itemx --as @var{path} Specifies the path, including the filename, of the assembler to be used to create the exports file. @item -f @var{options} @itemx --as-flags @var{options} Specifies any specific command line options to be passed to the assembler when building the exports file. This option will work even if the @option{-S} option is not used. This option only takes one argument, and if it occurs more than once on the command line, then later occurrences will override earlier occurrences. So if it is necessary to pass multiple options to the assembler they should be enclosed in double quotes. @item -D @var{name} @itemx --dll-name @var{name} Specifies the name to be stored in the @file{.def} file as the name of the DLL when the @option{-e} option is used. If this option is not present, then the filename given to the @option{-e} option will be used as the name of the DLL. @item -m @var{machine} @itemx -machine @var{machine} Specifies the type of machine for which the library file should be built. @command{dlltool} has a built in default type, depending upon how it was created, but this option can be used to override that. This is normally only useful when creating DLLs for an ARM processor, when the contents of the DLL are actually encode using Thumb instructions. @item -a @itemx --add-indirect Specifies that when @command{dlltool} is creating the exports file it should add a section which allows the exported functions to be referenced without using the import library. Whatever the hell that means! @item -U @itemx --add-underscore Specifies that when @command{dlltool} is creating the exports file it should prepend an underscore to the names of @emph{all} exported symbols. @item --add-stdcall-underscore Specifies that when @command{dlltool} is creating the exports file it should prepend an underscore to the names of exported @emph{stdcall} functions. Variable names and non-stdcall function names are not modified. This option is useful when creating GNU-compatible import libs for third party DLLs that were built with MS-Windows tools. @item -k @itemx --kill-at Specifies that when @command{dlltool} is creating the exports file it should not append the string @samp{@@ }. These numbers are called ordinal numbers and they represent another way of accessing the function in a DLL, other than by name. @item -A @itemx --add-stdcall-alias Specifies that when @command{dlltool} is creating the exports file it should add aliases for stdcall symbols without @samp{@@ } in addition to the symbols with @samp{@@ }. @item -p @itemx --ext-prefix-alias @var{prefix} Causes @command{dlltool} to create external aliases for all DLL imports with the specified prefix. The aliases are created for both external and import symbols with no leading underscore. @item -x @itemx --no-idata4 Specifies that when @command{dlltool} is creating the exports and library files it should omit the @code{.idata4} section. This is for compatibility with certain operating systems. @item -c @itemx --no-idata5 Specifies that when @command{dlltool} is creating the exports and library files it should omit the @code{.idata5} section. This is for compatibility with certain operating systems. @item -i @itemx --interwork Specifies that @command{dlltool} should mark the objects in the library file and exports file that it produces as supporting interworking between ARM and Thumb code. @item -n @itemx --nodelete Makes @command{dlltool} preserve the temporary assembler files it used to create the exports file. If this option is repeated then dlltool will also preserve the temporary object files it uses to create the library file. @item -t @var{prefix} @itemx --temp-prefix @var{prefix} Makes @command{dlltool} use @var{prefix} when constructing the names of temporary assembler and object files. By default, the temp file prefix is generated from the pid. @item -v @itemx --verbose Make dlltool describe what it is doing. @item -h @itemx --help Displays a list of command line options and then exits. @item -V @itemx --version Displays dlltool's version number and then exits. @end table @c man end @menu * def file format:: The format of the dlltool @file{.def} file @end menu @node def file format @section The format of the @command{dlltool} @file{.def} file A @file{.def} file contains any number of the following commands: @table @asis @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]} The result is going to be named @var{name}@code{.exe}. @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]} The result is going to be named @var{name}@code{.dll}. @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) )} @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *} Declares @var{name1} as an exported symbol from the DLL, with optional ordinal number @var{integer}, or declares @var{name1} as an alias (forward) of the function @var{external-name} in the DLL @var{module-name}. @item @code{IMPORTS ( (} @var{internal-name} @code{=} @var{module-name} @code{.} @var{integer} @code{) | [} @var{internal-name} @code{= ]} @var{module-name} @code{.} @var{external-name} @code{) ) *} Declares that @var{external-name} or the exported function whose ordinal number is @var{integer} is to be imported from the file @var{module-name}. If @var{internal-name} is specified then this is the name that the imported function will be referred to in the body of the DLL. @item @code{DESCRIPTION} @var{string} Puts @var{string} into the output @file{.exp} file in the @code{.rdata} section. @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]} @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]} Generates @code{--stack} or @code{--heap} @var{number-reserve},@var{number-commit} in the output @code{.drectve} section. The linker will see this and act upon it. @item @code{CODE} @var{attr} @code{+} @item @code{DATA} @var{attr} @code{+} @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *} Generates @code{--attr} @var{section-name} @var{attr} in the output @code{.drectve} section, where @var{attr} is one of @code{READ}, @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see this and act upon it. @end table @ignore @c man begin SEEALSO dlltool The Info pages for @file{binutils}. @c man end @end ignore @node readelf @chapter readelf @cindex ELF file information @kindex readelf @c man title readelf Displays information about ELF files. @smallexample @c man begin SYNOPSIS readelf readelf [@option{-a}|@option{--all}] [@option{-h}|@option{--file-header}] [@option{-l}|@option{--program-headers}|@option{--segments}] [@option{-S}|@option{--section-headers}|@option{--sections}] [@option{-g}|@option{--section-groups}] [@option{-t}|@option{--section-details}] [@option{-e}|@option{--headers}] [@option{-s}|@option{--syms}|@option{--symbols}] [@option{-n}|@option{--notes}] [@option{-r}|@option{--relocs}] [@option{-u}|@option{--unwind}] [@option{-d}|@option{--dynamic}] [@option{-V}|@option{--version-info}] [@option{-A}|@option{--arch-specific}] [@option{-D}|@option{--use-dynamic}] [@option{-x} |@option{--hex-dump=}] [@option{-w[liaprmfFsoR]}| @option{--debug-dump}[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]] [@option{-I}|@option{-histogram}] [@option{-v}|@option{--version}] [@option{-W}|@option{--wide}] [@option{-H}|@option{--help}] @var{elffile}@dots{} @c man end @end smallexample @c man begin DESCRIPTION readelf @command{readelf} displays information about one or more ELF format object files. The options control what particular information to display. @var{elffile}@dots{} are the object files to be examined. 32-bit and 64-bit ELF files are supported, as are archives containing ELF files. This program performs a similar function to @command{objdump} but it goes into more detail and it exists independently of the @sc{bfd} library, so if there is a bug in @sc{bfd} then readelf will not be affected. @c man end @c man begin OPTIONS readelf The long and short forms of options, shown here as alternatives, are equivalent. At least one option besides @samp{-v} or @samp{-H} must be given. @table @env @item -a @itemx --all Equivalent to specifiying @option{--file-header}, @option{--program-headers}, @option{--sections}, @option{--symbols}, @option{--relocs}, @option{--dynamic}, @option{--notes} and @option{--version-info}. @item -h @itemx --file-header @cindex ELF file header information Displays the information contained in the ELF header at the start of the file. @item -l @itemx --program-headers @itemx --segments @cindex ELF program header information @cindex ELF segment information Displays the information contained in the file's segment headers, if it has any. @item -S @itemx --sections @itemx --section-headers @cindex ELF section information Displays the information contained in the file's section headers, if it has any. @item -g @itemx --section-groups @cindex ELF section group information Displays the information contained in the file's section groups, if it has any. @item -t @itemx --section-details @cindex ELF section information Displays the detailed section information. Implies @option{-S}. @item -s @itemx --symbols @itemx --syms @cindex ELF symbol table information Displays the entries in symbol table section of the file, if it has one. @item -e @itemx --headers Display all the headers in the file. Equivalent to @option{-h -l -S}. @item -n @itemx --notes @cindex ELF notes Displays the contents of the NOTE segments and/or sections, if any. @item -r @itemx --relocs @cindex ELF reloc information Displays the contents of the file's relocation section, if it has one. @item -u @itemx --unwind @cindex unwind information Displays the contents of the file's unwind section, if it has one. Only the unwind sections for IA64 ELF files are currently supported. @item -d @itemx --dynamic @cindex ELF dynamic section information Displays the contents of the file's dynamic section, if it has one. @item -V @itemx --version-info @cindex ELF version sections informations Displays the contents of the version sections in the file, it they exist. @item -A @itemx --arch-specific Displays architecture-specific information in the file, if there is any. @item -D @itemx --use-dynamic When displaying symbols, this option makes @command{readelf} use the symbol table in the file's dynamic section, rather than the one in the symbols section. @item -x @itemx --hex-dump= Displays the contents of the indicated section as a hexadecimal dump. A number identifies a particular section by index in the section table; any other string identifies all sections with that name in the object file. @item -w[liaprmfFsoR] @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges] Displays the contents of the debug sections in the file, if any are present. If one of the optional letters or words follows the switch then only data found in those specific sections will be dumped. @item -I @itemx --histogram Display a histogram of bucket list lengths when displaying the contents of the symbol tables. @item -v @itemx --version Display the version number of readelf. @item -W @itemx --wide Don't break output lines to fit into 80 columns. By default @command{readelf} breaks section header and segment listing lines for 64-bit ELF files, so that they fit into 80 columns. This option causes @command{readelf} to print each section header resp. each segment one a single line, which is far more readable on terminals wider than 80 columns. @item -H @itemx --help Display the command line options understood by @command{readelf}. @end table @c man end @ignore @c man begin SEEALSO readelf objdump(1), and the Info entries for @file{binutils}. @c man end @end ignore @node Common Options @chapter Common Options The following command-line options are supported by all of the programs described in this manual. @c man begin OPTIONS @table @env @include at-file.texi @c man end @item --help Display the command-line options supported by the program. @item --version Display the version number of the program. @c man begin OPTIONS @end table @c man end @node Selecting The Target System @chapter Selecting the Target System You can specify two aspects of the target system to the @sc{gnu} binary file utilities, each in several ways: @itemize @bullet @item the target @item the architecture @end itemize In the following summaries, the lists of ways to specify values are in order of decreasing precedence. The ways listed first override those listed later. The commands to list valid values only list the values for which the programs you are running were configured. If they were configured with @option{--enable-targets=all}, the commands list most of the available values, but a few are left out; not all targets can be configured in at once because some of them can only be configured @dfn{native} (on hosts with the same type as the target system). @menu * Target Selection:: * Architecture Selection:: @end menu @node Target Selection @section Target Selection A @dfn{target} is an object file format. A given target may be supported for multiple architectures (@pxref{Architecture Selection}). A target selection may also have variations for different operating systems or architectures. The command to list valid target values is @samp{objdump -i} (the first column of output contains the relevant information). Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips}, @samp{a.out-sunos-big}. You can also specify a target using a configuration triplet. This is the same sort of name that is passed to @file{configure} to specify a target. When you use a configuration triplet as an argument, it must be fully canonicalized. You can see the canonical version of a triplet by running the shell script @file{config.sub} which is included with the sources. Some sample configuration triplets are: @samp{m68k-hp-bsd}, @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}. @subheading @command{objdump} Target Ways to specify: @enumerate @item command line option: @option{-b} or @option{--target} @item environment variable @code{GNUTARGET} @item deduced from the input file @end enumerate @subheading @command{objcopy} and @command{strip} Input Target Ways to specify: @enumerate @item command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target} @item environment variable @code{GNUTARGET} @item deduced from the input file @end enumerate @subheading @command{objcopy} and @command{strip} Output Target Ways to specify: @enumerate @item command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target} @item the input target (see ``@command{objcopy} and @command{strip} Input Target'' above) @item environment variable @code{GNUTARGET} @item deduced from the input file @end enumerate @subheading @command{nm}, @command{size}, and @command{strings} Target Ways to specify: @enumerate @item command line option: @option{--target} @item environment variable @code{GNUTARGET} @item deduced from the input file @end enumerate @node Architecture Selection @section Architecture Selection An @dfn{architecture} is a type of @sc{cpu} on which an object file is to run. Its name may contain a colon, separating the name of the processor family from the name of the particular @sc{cpu}. The command to list valid architecture values is @samp{objdump -i} (the second column contains the relevant information). Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}. @subheading @command{objdump} Architecture Ways to specify: @enumerate @item command line option: @option{-m} or @option{--architecture} @item deduced from the input file @end enumerate @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture Ways to specify: @enumerate @item deduced from the input file @end enumerate @node Reporting Bugs @chapter Reporting Bugs @cindex bugs @cindex reporting bugs Your bug reports play an essential role in making the binary utilities reliable. Reporting a bug may help you by bringing a solution to your problem, or it may not. But in any case the principal function of a bug report is to help the entire community by making the next version of the binary utilities work better. Bug reports are your contribution to their maintenance. In order for a bug report to serve its purpose, you must include the information that enables us to fix the bug. @menu * Bug Criteria:: Have you found a bug? * Bug Reporting:: How to report bugs @end menu @node Bug Criteria @section Have You Found a Bug? @cindex bug criteria If you are not sure whether you have found a bug, here are some guidelines: @itemize @bullet @cindex fatal signal @cindex crash @item If a binary utility gets a fatal signal, for any input whatever, that is a bug. Reliable utilities never crash. @cindex error on valid input @item If a binary utility produces an error message for valid input, that is a bug. @item If you are an experienced user of binary utilities, your suggestions for improvement are welcome in any case. @end itemize @node Bug Reporting @section How to Report Bugs @cindex bug reports @cindex bugs, reporting A number of companies and individuals offer support for @sc{gnu} products. If you obtained the binary utilities from a support organization, we recommend you contact that organization first. You can find contact information for many support companies and individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs distribution. In any event, we also recommend that you send bug reports for the binary utilities to @samp{bug-binutils@@gnu.org}. The fundamental principle of reporting bugs usefully is this: @strong{report all the facts}. If you are not sure whether to state a fact or leave it out, state it! Often people omit facts because they think they know what causes the problem and assume that some details do not matter. Thus, you might assume that the name of a file you use in an example does not matter. Well, probably it does not, but one cannot be sure. Perhaps the bug is a stray memory reference which happens to fetch from the location where that pathname is stored in memory; perhaps, if the pathname were different, the contents of that location would fool the utility into doing the right thing despite the bug. Play it safe and give a specific, complete example. That is the easiest thing for you to do, and the most helpful. Keep in mind that the purpose of a bug report is to enable us to fix the bug if it is new to us. Therefore, always write your bug reports on the assumption that the bug has not been reported previously. Sometimes people give a few sketchy facts and ask, ``Does this ring a bell?'' This cannot help us fix a bug, so it is basically useless. We respond by asking for enough details to enable us to investigate. You might as well expedite matters by sending them to begin with. To enable us to fix the bug, you should include all these things: @itemize @bullet @item The version of the utility. Each utility announces it if you start it with the @option{--version} argument. Without this, we will not know whether there is any point in looking for the bug in the current version of the binary utilities. @item Any patches you may have applied to the source, including any patches made to the @code{BFD} library. @item The type of machine you are using, and the operating system name and version number. @item What compiler (and its version) was used to compile the utilities---e.g. ``@code{gcc-2.7}''. @item The command arguments you gave the utility to observe the bug. To guarantee you will not omit something important, list them all. A copy of the Makefile (or the output from make) is sufficient. If we were to try to guess the arguments, we would probably guess wrong and then we might not encounter the bug. @item A complete input file, or set of input files, that will reproduce the bug. If the utility is reading an object file or files, then it is generally most helpful to send the actual object files, uuencoded if necessary to get them through the mail system. Note that @samp{bug-binutils@@gnu.org} is a mailing list, so you should avoid sending very large files to it. Making the files available for anonymous FTP is OK. If the source files were produced exclusively using @sc{gnu} programs (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it may be OK to send the source files rather than the object files. In this case, be sure to say exactly what version of @command{gcc}, or whatever, was used to produce the object files. Also say how @command{gcc}, or whatever, was configured. @item A description of what behavior you observe that you believe is incorrect. For example, ``It gets a fatal signal.'' Of course, if the bug is that the utility gets a fatal signal, then we will certainly notice it. But if the bug is incorrect output, we might not notice unless it is glaringly wrong. You might as well not give us a chance to make a mistake. Even if the problem you experience is a fatal signal, you should still say so explicitly. Suppose something strange is going on, such as your copy of the utility is out of synch, or you have encountered a bug in the C library on your system. (This has happened!) Your copy might crash and ours would not. If you told us to expect a crash, then when ours fails to crash, we would know that the bug was not happening for us. If you had not told us to expect a crash, then we would not be able to draw any conclusion from our observations. @item If you wish to suggest changes to the source, send us context diffs, as generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p} option. Always send diffs from the old file to the new file. If you wish to discuss something in the @command{ld} source, refer to it by context, not by line number. The line numbers in our development sources will not match those in your sources. Your line numbers would convey no useful information to us. @end itemize Here are some things that are not necessary: @itemize @bullet @item A description of the envelope of the bug. Often people who encounter a bug spend a lot of time investigating which changes to the input file will make the bug go away and which changes will not affect it. This is often time consuming and not very useful, because the way we will find the bug is by running a single example under the debugger with breakpoints, not by pure deduction from a series of examples. We recommend that you save your time for something else. Of course, if you can find a simpler example to report @emph{instead} of the original one, that is a convenience for us. Errors in the output will be easier to spot, running under the debugger will take less time, and so on. However, simplification is not vital; if you do not want to do this, report the bug anyway and send us the entire test case you used. @item A patch for the bug. A patch for the bug does help us if it is a good one. But do not omit the necessary information, such as the test case, on the assumption that a patch is all we need. We might see problems with your patch and decide to fix the problem another way, or we might not understand it at all. Sometimes with programs as complicated as the binary utilities it is very hard to construct an example that will make the program follow a certain path through the code. If you do not send us the example, we will not be able to construct one, so we will not be able to verify that the bug is fixed. And if we cannot understand what bug you are trying to fix, or why your patch should be an improvement, we will not install it. A test case will help us to understand. @item A guess about what the bug is or what it depends on. Such guesses are usually wrong. Even we cannot guess right about such things without first using the debugger to find the facts. @end itemize @include fdl.texi @node Index @unnumbered Index @printindex cp @contents @bye