| \input texinfo @c -*- Texinfo -*- |
| @setfilename binutils.info |
| @include config.texi |
| |
| @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 |
| Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc. |
| |
| Permission is granted to make and distribute verbatim copies of |
| this manual provided the copyright notice and this permission notice |
| are preserved on all copies. |
| |
| @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 |
| |
| Permission is granted to copy and distribute modified versions of this |
| manual under the conditions for verbatim copying, provided also that |
| the entire resulting derived work is distributed under the terms of a |
| permission notice identical to this one. |
| |
| Permission is granted to copy and distribute translations of this manual |
| into another language, under the above conditions for modified versions. |
| @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, 92, 93, 94, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc. |
| @c |
| @c This text may be freely distributed under the terms of the GNU |
| @c General Public License. |
| @c |
| |
| @setchapternewpage odd |
| @settitle @sc{gnu} Binary Utilities |
| @titlepage |
| @finalout |
| @title The @sc{gnu} Binary Utilities |
| @subtitle Version @value{VERSION} |
| @sp 1 |
| @subtitle May 1993 |
| @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, 92, 93, 94, 95, 96, 97, 1998 Free Software Foundation, Inc. |
| |
| Permission is granted to make and distribute verbatim copies of |
| this manual provided the copyright notice and this permission notice |
| are preserved on all copies. |
| |
| Permission is granted to copy and distribute modified versions of this |
| manual under the conditions for verbatim copying, provided also that |
| the entire resulting derived work is distributed under the terms of a |
| permission notice identical to this one. |
| |
| Permission is granted to copy and distribute translations of this manual |
| into another language, under the above conditions for modified versions. |
| @end titlepage |
| |
| @node Top |
| @top Introduction |
| |
| @cindex version |
| This brief manual contains preliminary 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 |
| |
| @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 |
| * Selecting The Target System:: How these utilities determine the target. |
| * Reporting Bugs:: Reporting Bugs |
| * Index:: Index |
| @end menu |
| |
| @node ar |
| @chapter ar |
| |
| @kindex ar |
| @cindex archives |
| @cindex collections of files |
| @smallexample |
| ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}] |
| ar -M [ <mri-script ] |
| @end smallexample |
| |
| The @sc{gnu} @code{ar} program creates, modifies, and extracts from |
| archives. An @dfn{archive} is a single file holding a collection of |
| other files in a structure that makes it possible to retrieve |
| the original individual files (called @dfn{members} of the archive). |
| |
| The original files' contents, mode (permissions), timestamp, owner, and |
| group are preserved in the archive, and can be restored on |
| extraction. |
| |
| @cindex name length |
| @sc{gnu} @code{ar} can maintain archives whose members have names of any |
| length; however, depending on how @code{ar} is configured on your |
| system, a limit on member-name length may be imposed for compatibility |
| with archive formats maintained with other tools. If it exists, the |
| limit is often 15 characters (typical of formats related to a.out) or 16 |
| characters (typical of formats related to coff). |
| |
| @cindex libraries |
| @code{ar} is considered a binary utility because archives of this sort |
| are most often used as @dfn{libraries} holding commonly needed |
| subroutines. |
| |
| @cindex symbol index |
| @code{ar} creates an index to the symbols defined in relocatable |
| object modules in the archive when you specify the modifier @samp{s}. |
| Once created, this index is updated in the archive whenever @code{ar} |
| makes a change to its contents (save for the @samp{q} update operation). |
| 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. |
| |
| You may use @samp{nm -s} or @samp{nm --print-armap} to list this index |
| table. If an archive lacks the table, another form of @code{ar} called |
| @code{ranlib} can be used to add just the table. |
| |
| @cindex compatibility, @code{ar} |
| @cindex @code{ar} compatibility |
| @sc{gnu} @code{ar} is designed to be compatible with two different |
| facilities. You can control its activity using command-line options, |
| like the different varieties of @code{ar} on Unix systems; or, if you |
| specify the single command-line option @samp{-M}, you can control it |
| with a script supplied via standard input, like the MRI ``librarian'' |
| program. |
| |
| @menu |
| * ar cmdline:: Controlling @code{ar} on the command line |
| * ar scripts:: Controlling @code{ar} with a script |
| @end menu |
| |
| @page |
| @node ar cmdline |
| @section Controlling @code{ar} on the command line |
| |
| @smallexample |
| ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}] |
| @end smallexample |
| |
| @cindex Unix compatibility, @code{ar} |
| When you use @code{ar} in the Unix style, @code{ar} insists on at least two |
| arguments to execute: one keyletter specifying the @emph{operation} |
| (optionally accompanied by other keyletters specifying |
| @emph{modifiers}), and the archive name to act on. |
| |
| Most operations can also accept further @var{member} arguments, |
| specifying particular files to operate on. |
| |
| @sc{gnu} @code{ar} allows you to mix the operation code @var{p} and modifier |
| flags @var{mod} in any order, within the first command-line argument. |
| |
| If you wish, you may begin the first command-line argument with a |
| dash. |
| |
| @cindex operations on archive |
| The @var{p} keyletter specifies what operation to execute; it may be |
| any of the following, but you must specify only one of them: |
| |
| @table @code |
| @item d |
| @cindex deleting from archive |
| @emph{Delete} modules from the archive. Specify the names of modules to |
| be deleted as @var{member}@dots{}; the archive is untouched if you |
| specify no files to delete. |
| |
| If you specify the @samp{v} modifier, @code{ar} lists each module |
| as it is deleted. |
| |
| @item m |
| @cindex moving in archive |
| Use this operation to @emph{move} members in an archive. |
| |
| The ordering of members in an archive can make a difference in how |
| programs are linked using the library, if a symbol is defined in more |
| than one member. |
| |
| If no modifiers are used with @code{m}, any members you name in the |
| @var{member} arguments are moved to the @emph{end} of the archive; |
| you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a |
| specified place instead. |
| |
| @item p |
| @cindex printing from archive |
| @emph{Print} the specified members of the archive, to the standard |
| output file. If the @samp{v} modifier is specified, show the member |
| name before copying its contents to standard output. |
| |
| If you specify no @var{member} arguments, all the files in the archive are |
| printed. |
| |
| @item q |
| @cindex quick append to archive |
| @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of |
| @var{archive}, without checking for replacement. |
| |
| The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this |
| operation; new members are always placed at the end of the archive. |
| |
| The modifier @samp{v} makes @code{ar} list each file as it is appended. |
| |
| Since the point of this operation is speed, the archive's symbol table |
| index is not updated, even if it already existed; you can use @samp{ar s} or |
| @code{ranlib} explicitly to update the symbol table index. |
| |
| However, too many different systems assume quick append rebuilds the |
| index, so GNU ar implements @code{q} as a synonym for @code{r}. |
| |
| @item r |
| @cindex replacement in archive |
| Insert the files @var{member}@dots{} into @var{archive} (with |
| @emph{replacement}). This operation differs from @samp{q} in that any |
| previously existing members are deleted if their names match those being |
| added. |
| |
| If one of the files named in @var{member}@dots{} does not exist, @code{ar} |
| displays an error message, and leaves undisturbed any existing members |
| of the archive matching that name. |
| |
| By default, new members are added at the end of the file; but you may |
| use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request |
| placement relative to some existing member. |
| |
| The modifier @samp{v} used with this operation elicits a line of |
| output for each file inserted, along with one of the letters @samp{a} or |
| @samp{r} to indicate whether the file was appended (no old member |
| deleted) or replaced. |
| |
| @item t |
| @cindex contents of archive |
| Display a @emph{table} listing the contents of @var{archive}, or those |
| of the files listed in @var{member}@dots{} that are present in the |
| archive. Normally only the member name is shown; if you also want to |
| see the modes (permissions), timestamp, owner, group, and size, you can |
| request that by also specifying the @samp{v} modifier. |
| |
| If you do not specify a @var{member}, all files in the archive |
| are listed. |
| |
| @cindex repeated names in archive |
| @cindex name duplication in archive |
| If there is more than one file with the same name (say, @samp{fie}) in |
| an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the |
| first instance; to see them all, you must ask for a complete |
| listing---in our example, @samp{ar t b.a}. |
| @c WRS only; per Gumby, this is implementation-dependent, and in a more |
| @c recent case in fact works the other way. |
| |
| @item x |
| @cindex extract from archive |
| @emph{Extract} members (named @var{member}) from the archive. You can |
| use the @samp{v} modifier with this operation, to request that |
| @code{ar} list each name as it extracts it. |
| |
| If you do not specify a @var{member}, all files in the archive |
| are extracted. |
| |
| @end table |
| |
| A number of modifiers (@var{mod}) may immediately follow the @var{p} |
| keyletter, to specify variations on an operation's behavior: |
| |
| @table @code |
| @item a |
| @cindex relative placement in archive |
| Add new files @emph{after} an existing member of the |
| archive. If you use the modifier @samp{a}, the name of an existing archive |
| member must be present as the @var{relpos} argument, before the |
| @var{archive} specification. |
| |
| @item b |
| Add new files @emph{before} an existing member of the |
| archive. If you use the modifier @samp{b}, the name of an existing archive |
| member must be present as the @var{relpos} argument, before the |
| @var{archive} specification. (same as @samp{i}). |
| |
| @item c |
| @cindex creating archives |
| @emph{Create} the archive. The specified @var{archive} is always |
| created if it did not exist, when you request an update. But a warning is |
| issued unless you specify in advance that you expect to create it, by |
| using this modifier. |
| |
| @item f |
| Truncate names in the archive. @sc{gnu} @code{ar} will normally permit file |
| names of any length. This will cause it to create archives which are |
| not compatible with the native @code{ar} program on some systems. If |
| this is a concern, the @samp{f} modifier may be used to truncate file |
| names when putting them in the archive. |
| |
| @item i |
| Insert new files @emph{before} an existing member of the |
| archive. If you use the modifier @samp{i}, the name of an existing archive |
| member must be present as the @var{relpos} argument, before the |
| @var{archive} specification. (same as @samp{b}). |
| |
| @item l |
| This modifier is accepted but not used. |
| @c whaffor ar l modifier??? presumably compat; with |
| @c what???---doc@@cygnus.com, 25jan91 |
| |
| @item N |
| Uses the @var{count} parameter. This is used if there are multiple |
| entries in the archive with the same name. Extract or delete instance |
| @var{count} of the given name from the archive. |
| |
| @item o |
| @cindex dates in archive |
| Preserve the @emph{original} dates of members when extracting them. If |
| you do not specify this modifier, files extracted from the archive |
| are stamped with the time of extraction. |
| |
| @item P |
| Use the full path name when matching names in the archive. @sc{gnu} |
| @code{ar} can not create an archive with a full path name (such archives |
| are not POSIX complaint), but other archive creators can. This option |
| will cause @sc{gnu} @code{ar} to match file names using a complete path |
| name, which can be convenient when extracting a single file from an |
| archive created by another tool. |
| |
| @item s |
| @cindex writing archive index |
| Write an object-file index into the archive, or update an existing one, |
| even if no other change is made to the archive. You may use this modifier |
| flag either with any operation, or alone. Running @samp{ar s} on an |
| archive is equivalent to running @samp{ranlib} on it. |
| |
| @item S |
| @cindex not writing archive index |
| Do not generate an archive symbol table. This can speed up building a |
| large library in several steps. The resulting archive can not be used |
| with the linker. In order to build a symbol table, you must omit the |
| @samp{S} modifier on the last execution of @samp{ar}, or you must run |
| @samp{ranlib} on the archive. |
| |
| @item u |
| @cindex updating an archive |
| Normally, @samp{ar r}@dots{} inserts all files |
| listed into the archive. If you would like to insert @emph{only} those |
| of the files you list that are newer than existing members of the same |
| names, use this modifier. The @samp{u} modifier is allowed only for the |
| operation @samp{r} (replace). In particular, the combination @samp{qu} is |
| not allowed, since checking the timestamps would lose any speed |
| advantage from the operation @samp{q}. |
| |
| @item v |
| This modifier requests the @emph{verbose} version of an operation. Many |
| operations display additional information, such as filenames processed, |
| when the modifier @samp{v} is appended. |
| |
| @item V |
| This modifier shows the version number of @code{ar}. |
| @end table |
| |
| @node ar scripts |
| @section Controlling @code{ar} with a script |
| |
| @smallexample |
| ar -M [ <@var{script} ] |
| @end smallexample |
| |
| @cindex MRI compatibility, @code{ar} |
| @cindex scripts, @code{ar} |
| If you use the single command-line option @samp{-M} with @code{ar}, you |
| can control its operation with a rudimentary command language. This |
| form of @code{ar} operates interactively if standard input is coming |
| directly from a terminal. During interactive use, @code{ar} prompts for |
| input (the prompt is @samp{AR >}), and continues executing even after |
| errors. If you redirect standard input to a script file, no prompts are |
| issued, and @code{ar} abandons execution (with a nonzero exit code) |
| on any error. |
| |
| The @code{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} @code{ar} for developers who already have scripts |
| written for the MRI ``librarian'' program. |
| |
| The syntax for the @code{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 @code{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 @code{ar} scripts, or when using |
| @code{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, @code{ar} directs the |
| output to that file. |
| |
| @item END |
| Exit from @code{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} @code{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 @code{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 |
| |
| @smallexample |
| nm [ -a | --debug-syms ] [ -g | --extern-only ] |
| [ -B ] [ -C | --demangle ] [ -D | --dynamic ] |
| [ -s | --print-armap ] [ -A | -o | --print-file-name ] |
| [ -n | -v | --numeric-sort ] [ -p | --no-sort ] |
| [ -r | --reverse-sort ] [ --size-sort ] [ -u | --undefined-only ] |
| [ -t @var{radix} | --radix=@var{radix} ] [ -P | --portability ] |
| [ --target=@var{bfdname} ] [ -f @var{format} | --format=@var{format} ] |
| [ --defined-only ] [-l | --line-numbers ] |
| [ --no-demangle ] [ -V | --version ] [ --help ] [ @var{objfile}@dots{} ] |
| @end smallexample |
| |
| @sc{gnu} @code{nm} lists the symbols from object files @var{objfile}@dots{}. |
| If no object files are listed as arguments, @code{nm} assumes the file |
| @file{a.out}. |
| |
| For each symbol, @code{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. For more details on common symbols, see the discussion of |
| --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}. |
| |
| @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 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 weak symbol becomes zero with no error. |
| |
| @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; |
| for more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The |
| ``stabs'' debug format}. |
| |
| @item ? |
| The symbol type is unknown, or object file format specific. |
| @end table |
| |
| @item |
| The symbol name. |
| @end itemize |
| |
| The long and short forms of options, shown here as alternatives, are |
| equivalent. |
| |
| @table @code |
| @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 @code{nm} format |
| @cindex @code{nm} compatibility |
| The same as @samp{--format=bsd} (for compatibility with the MIPS @code{nm}). |
| |
| @item -C |
| @itemx --demangle |
| @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. @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 @code{nm} format |
| @cindex @code{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-armap |
| @cindex symbol index, listing |
| When listing symbols from archive members, include the index: a mapping |
| (stored in the archive by @code{ar} or @code{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. The size of the symbol is printed, rather than the value. |
| |
| @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 @code{nm} and exit. |
| |
| @item --help |
| Show a summary of the options to @code{nm} and exit. |
| @end table |
| |
| @node objcopy |
| @chapter objcopy |
| |
| @smallexample |
| objcopy [ -F @var{bfdname} | --target=@var{bfdname} ] |
| [ -I @var{bfdname} | --input-target=@var{bfdname} ] |
| [ -O @var{bfdname} | --output-target=@var{bfdname} ] |
| [ -S | --strip-all ] [ -g | --strip-debug ] |
| [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ] |
| [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ] |
| [ -L @var{symbolname} | --localize-symbol=@var{symbolname} ] |
| [ -W @var{symbolname} | --weaken-symbol=@var{symbolname} ] |
| [ -x | --discard-all ] [ -X | --discard-locals ] |
| [ -b @var{byte} | --byte=@var{byte} ] |
| [ -i @var{interleave} | --interleave=@var{interleave} ] |
| [ -j @var{sectionname} | --only-section=@var{sectionname} ] |
| [ -R @var{sectionname} | --remove-section=@var{sectionname} ] |
| [ -p | --preserve-dates ] [ --debugging ] |
| [ --gap-fill=@var{val} ] [ --pad-to=@var{address} ] |
| [ --set-start=@var{val} ] [ --adjust-start=@var{incr} ] |
| [ --change-addresses=@var{incr} ] |
| [ --change-section-address=@var{section}@{=,+,-@}@var{val} ] |
| [ --change-section-lma=@var{section}@{=,+,-@}@var{val} ] |
| [ --change-section-vma=@var{section}@{=,+,-@}@var{val} ] |
| [ --change-warnings ] [ --no-change-warnings ] |
| [ --set-section-flags=@var{section}=@var{flags} ] |
| [ --add-section=@var{sectionname}=@var{filename} ] |
| [ --change-leading-char ] [ --remove-leading-char ] |
| [ --weaken ] |
| [ -v | --verbose ] [ -V | --version ] [ --help ] |
| @var{infile} [@var{outfile}] |
| @end smallexample |
| |
| The @sc{gnu} @code{objcopy} utility copies the contents of an object |
| file to another. @code{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 @code{objcopy} is controlled by command-line options. |
| |
| @code{objcopy} creates temporary files to do its translations and |
| deletes them afterward. @code{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}. |
| |
| @code{objcopy} can be used to generate S-records by using an output |
| target of @samp{srec} (e.g., use @samp{-O srec}). |
| |
| @code{objcopy} can be used to generate a raw binary file by using an |
| output target of @samp{binary} (e.g., use @samp{-O binary}). When |
| @code{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 @samp{-S} to remove sections containing debugging information. In |
| some cases @samp{-R} will be useful to remove sections which contain |
| information that is not needed by the binary file. |
| |
| @table @code |
| @item @var{infile} |
| @itemx @var{outfile} |
| The input and output files, respectively. |
| If you do not specify @var{outfile}, @code{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 -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 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} |
| Copy only symbol @var{symbolname} from the source file. 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 -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 -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 @samp{-i} or @samp{--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 @var{-b} or @samp{--byte} option. The default is 4. |
| @code{objcopy} ignores this option if you do not specify either @samp{-b} or |
| @samp{--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 @samp{--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 @samp{--change-addresses}, |
| above. If @var{section} does not exist in the input file, a warning will |
| be issued, unless @samp{--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 @samp{--change-addresses}, |
| above. If @var{section} does not exist in the input file, a warning |
| will be issued, unless @samp{--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 |
| @samp{--change-addresses}, above. If @var{section} does not exist in |
| the input file, a warning will be issued, unless |
| @samp{--no-change-warnings} is used. |
| |
| @item --change-warnings |
| @itemx --adjust-warnings |
| If @samp{--change-section-address} or @samp{--change-section-lma} or |
| @samp{--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 @samp{--change-section-address} or |
| @samp{--adjust-section-lma} or @samp{--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 --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 @code{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 |
| @code{--change-leading-char} because it always changes the symbol name |
| when appropriate, regardless of the object file format of the output |
| file. |
| |
| @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 @code{-R} option to the linker. This option is only effective when |
| using an object file format which supports weak symbols. |
| |
| @item -V |
| @itemx --version |
| Show the version number of @code{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 @code{objcopy}. |
| @end table |
| |
| @node objdump |
| @chapter objdump |
| |
| @cindex object file information |
| @kindex objdump |
| |
| @smallexample |
| objdump [ -a | --archive-headers ] |
| [ -b @var{bfdname} | --target=@var{bfdname} ] |
| [ -C | --demangle ] |
| [ -d | --disassemble ] |
| [ -D | --disassemble-all ] |
| [ -z | --disassemble-zeroes ] |
| [ -EB | -EL | --endian=@{big | little @} ] |
| [ -f | --file-headers ] |
| [ --file-start-context ] |
| [ -g | --debugging ] |
| [ -h | --section-headers | --headers ] |
| [ -i | --info ] |
| [ -j @var{section} | --section=@var{section} ] |
| [ -l | --line-numbers ] |
| [ -S | --source ] |
| [ -m @var{machine} | --architecture=@var{machine} ] |
| [ -M @var{options} | --disassembler-options=@var{options}] |
| [ -p | --private-headers ] |
| [ -r | --reloc ] |
| [ -R | --dynamic-reloc ] |
| [ -s | --full-contents ] |
| [ -G | --stabs ] |
| [ -t | --syms ] |
| [ -T | --dynamic-syms ] |
| [ -x | --all-headers ] |
| [ -w | --wide ] |
| [ --start-address=@var{address} ] |
| [ --stop-address=@var{address} ] |
| [ --prefix-addresses] |
| [ --[no-]show-raw-insn ] |
| [ --adjust-vma=@var{offset} ] |
| [ -V | --version ] |
| [ -H | --help ] |
| @var{objfile}@dots{} |
| @end smallexample |
| |
| @code{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, @code{objdump} shows information on each of the member |
| object files. |
| |
| The long and short forms of options, shown here as alternatives, are |
| equivalent. At least one option from the list |
| @samp{-a,-d,-D,-f,-g,-G,-h,-H,-p,-r,-R,-S,-t,-T,-V,-x} must be given. |
| |
| @table @code |
| @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 (@samp{-h}) of |
| @file{fu.o}, which is explicitly identified (@samp{-m}) as a VAX object |
| file in the format produced by Oasys compilers. You can list the |
| formats available with the @samp{-i} option. |
| @xref{Target Selection}, for more information. |
| |
| @item -C |
| @itemx --demangle |
| @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. @xref{c++filt}, for more information |
| on demangling. |
| |
| @item -G |
| @item --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. |
| |
| @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 @samp{-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 --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. |
| |
| @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-header |
| @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 '-S') from a file that has not yet been displayed, extend the |
| context to the start of the file. |
| |
| @item -h |
| @itemx --section-header |
| @itemx --header |
| @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 @samp{-Ttext}, @samp{-Tdata}, or @samp{-Tbss} options to |
| @code{ld}. However, some object file formats, such as a.out, do not |
| store the starting address of the file segments. In those situations, |
| although @code{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 --help |
| Print a summary of the options to @code{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 @samp{-b} or @samp{-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 @samp{-d}, @samp{-D}, or @samp{-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 @samp{-i} option. |
| |
| @item -M @var{options} |
| @itemx --disassembler-options=@var{options} |
| Pass target specific information to the disassembler. Only supported on |
| some targets. |
| |
| If the target is an ARM architecture then this switch can be used to |
| select which register name set is used during disassembler. Specifying |
| @samp{-M reg-name-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 |
| @samp{-M reg-names-apcs} will select the name set used by the ARM |
| Procedure Call Standard, whilst specifying @samp{-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 @samp{-M reg-names-atpcs} and @samp{-M reg-names-special-atpcs} which |
| use the ARM/Thumb Procedure Call Standard naming conventions. (Eiuther |
| with the normal register name sor 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 @samp{--disassembler-options=force-thumb}. This can be |
| useful when attempting to disassemble thumb code produced by other |
| compilers. |
| |
| @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 @samp{-d} or |
| @samp{-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. |
| |
| @item -S |
| @itemx --source |
| @cindex source disassembly |
| @cindex disassembly, with source |
| Display source code intermixed with disassembly, if possible. Implies |
| @samp{-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 |
| @code{--prefix-addresses} is used. |
| |
| @item --no-show-raw-insn |
| When disassembling instructions, do not print the instruction bytes. |
| This is the default when @code{--prefix-addresses} is used. |
| |
| @item -G |
| @item --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 @samp{--syms} |
| output. For more information on stabs symbols, see @ref{Top,Stabs,Stabs |
| Overview,stabs.info, The ``stabs'' debug format}. |
| |
| @item --start-address=@var{address} |
| @cindex start-address |
| Start displaying data at the specified address. This affects the output |
| of the @code{-d}, @code{-r} and @code{-s} options. |
| |
| @item --stop-address=@var{address} |
| @cindex stop-address |
| Stop displaying data at the specified address. This affects the output |
| of the @code{-d}, @code{-r} and @code{-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 @samp{-D} (@samp{--dynamic}) option. |
| |
| @item --version |
| Print the version number of @code{objdump} and exit. |
| |
| @item -x |
| @itemx --all-header |
| @cindex all header information, object file |
| @cindex header information, all |
| Display all available header information, including the symbol table and |
| relocation entries. Using @samp{-x} is equivalent to specifying all of |
| @samp{-a -f -h -r -t}. |
| |
| @item -w |
| @itemx --wide |
| @cindex wide output, printing |
| Format some lines for output devices that have more than 80 columns. |
| @end table |
| |
| @node ranlib |
| @chapter ranlib |
| |
| @kindex ranlib |
| @cindex archive contents |
| @cindex symbol index |
| |
| @smallexample |
| ranlib [-vV] @var{archive} |
| @end smallexample |
| |
| @code{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} @code{ranlib} program is another form of @sc{gnu} @code{ar}; running |
| @code{ranlib} is completely equivalent to executing @samp{ar -s}. |
| @xref{ar}. |
| |
| @table @code |
| @item -v |
| @itemx -V |
| @itemx --version |
| Show the version number of @code{ranlib}. |
| @end table |
| |
| @node size |
| @chapter size |
| |
| @kindex size |
| @cindex section sizes |
| |
| @smallexample |
| size [ -A | -B | --format=@var{compatibility} ] |
| [ --help ] [ -d | -o | -x | --radix=@var{number} ] |
| [ --target=@var{bfdname} ] [ -V | --version ] |
| [ @var{objfile}@dots{} ] |
| @end smallexample |
| |
| The @sc{gnu} @code{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. |
| |
| The command line options have the following meanings: |
| |
| @table @code |
| @item -A |
| @itemx -B |
| @itemx --format=@var{compatibility} |
| @cindex @code{size} display format |
| Using one of these options, you can choose whether the output from @sc{gnu} |
| @code{size} resembles output from System V @code{size} (using @samp{-A}, |
| or @samp{--format=sysv}), or Berkeley @code{size} (using @samp{-B}, or |
| @samp{--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 |
| @code{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 @code{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 (@samp{-d}, or @samp{--radix=10}); octal |
| (@samp{-o}, or @samp{--radix=8}); or hexadecimal (@samp{-x}, or |
| @samp{--radix=16}). In @samp{--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 @samp{-d} or @samp{-x} output, or |
| octal and hexadecimal if you're using @samp{-o}. |
| |
| @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; @code{size} can |
| automatically recognize many formats. |
| @xref{Target Selection}, for more information. |
| |
| @item -V |
| @itemx --version |
| Display the version number of @code{size}. |
| @end table |
| |
| @node strings |
| @chapter strings |
| @kindex strings |
| @cindex listings strings |
| @cindex printing strings |
| @cindex strings, printing |
| |
| @smallexample |
| strings [-afov] [-@var{min-len}] [-n @var{min-len}] [-t @var{radix}] [-] |
| [--all] [--print-file-name] [--bytes=@var{min-len}] |
| [--radix=@var{radix}] [--target=@var{bfdname}] |
| [--help] [--version] @var{file}@dots{} |
| @end smallexample |
| |
| For each @var{file} given, @sc{gnu} @code{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. |
| |
| @code{strings} is mainly useful for determining the contents of non-text |
| files. |
| |
| @table @code |
| @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 @code{strings} have @samp{-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 --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 |
| |
| @node strip |
| @chapter strip |
| |
| @kindex strip |
| @cindex removing symbols |
| @cindex discarding symbols |
| @cindex symbols, discarding |
| |
| @smallexample |
| strip [ -F @var{bfdname} | --target=@var{bfdname} ] |
| [ -I @var{bfdname} | --input-target=@var{bfdname} ] |
| [ -O @var{bfdname} | --output-target=@var{bfdname} ] |
| [ -s | --strip-all ] [ -S | -g | --strip-debug ] |
| [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ] |
| [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ] |
| [ -x | --discard-all ] [ -X | --discard-locals ] |
| [ -R @var{sectionname} | --remove-section=@var{sectionname} ] |
| [ -o @var{file} ] [ -p | --preserve-dates ] |
| [ -v | --verbose ] [ -V | --version ] [ --help ] |
| @var{objfile}@dots{} |
| @end smallexample |
| |
| @sc{gnu} @code{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. |
| |
| @code{strip} modifies the files named in its argument, |
| rather than writing modified copies under different names. |
| |
| @table @code |
| @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 @code{strip} and exit. |
| |
| @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 --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} |
| Keep only symbol @var{symbolname} from the source file. 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 |
| @code{-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 -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 -V |
| @itemx --version |
| Show the version number for @code{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 |
| |
| @node c++filt, addr2line, strip, Top |
| @chapter c++filt |
| |
| @kindex c++filt |
| @cindex demangling C++ symbols |
| |
| @smallexample |
| c++filt [ -_ | --strip-underscores ] |
| [ -j | --java ] |
| [ -n | --no-strip-underscores ] |
| [ -s @var{format} | --format=@var{format} ] |
| [ --help ] [ --version ] [ @var{symbol}@dots{} ] |
| @end smallexample |
| |
| @kindex cxxfilt |
| The C++ and Java languages provides function overloading, which means |
| that you can write many functions with the same name (providing each |
| takes parameters of different types). All C++ and Java function names |
| are encoded into a low-level assembly label (this process is known as |
| @dfn{mangling}). The @code{c++filt} |
| @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on |
| MS-DOS this program is named @code{cxxfilt}.} |
| program does the inverse mapping: it decodes (@dfn{demangles}) low-level |
| names into user-level names so that the linker can keep these overloaded |
| functions from clashing. |
| |
| Every alphanumeric word (consisting of letters, digits, underscores, |
| dollars, or periods) seen in the input is a potential label. If the |
| label decodes into a C++ name, the C++ name replaces the low-level |
| name in the output. |
| |
| You can use @code{c++filt} to decipher individual symbols: |
| |
| @example |
| c++filt @var{symbol} |
| @end example |
| |
| If no @var{symbol} arguments are given, @code{c++filt} reads symbol |
| names from the standard input and writes the demangled names to the |
| standard output. All results are printed on the standard output. |
| |
| @table @code |
| @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 |
| @code{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 -s @var{format} |
| @itemx --format=@var{format} |
| @sc{gnu} @code{nm} can decode three different methods of mangling, used by |
| different C++ compilers. The argument to this option selects which |
| method it uses: |
| |
| @table @code |
| @item gnu |
| the one used by the @sc{gnu} compiler (the default method) |
| @item lucid |
| the one used by the Lucid compiler |
| @item arm |
| the one specified by the C++ Annotated Reference Manual |
| @item hp |
| the one used by the HP compiler |
| @item edg |
| the one used by the EDG compiler |
| @end table |
| |
| @item --help |
| Print a summary of the options to @code{c++filt} and exit. |
| |
| @item --version |
| Print the version number of @code{c++filt} and exit. |
| @end table |
| |
| @quotation |
| @emph{Warning:} @code{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 |
| |
| @smallexample |
| addr2line [ -b @var{bfdname} | --target=@var{bfdname} ] |
| [ -C | --demangle ] |
| [ -e @var{filename} | --exe=@var{filename} ] |
| [ -f | --functions ] [ -s | --basename ] |
| [ -H | --help ] [ -V | --version ] |
| [ addr addr ... ] |
| @end smallexample |
| |
| @code{addr2line} translates program addresses into file names and line |
| numbers. Given an address and an executable, it uses the debugging |
| information in the executable to figure out which file name and line |
| number are associated with a given address. |
| |
| The executable to use is specified with the @code{-e} option. The |
| default is the file @file{a.out}. |
| |
| @code{addr2line} has two modes of operation. |
| |
| In the first, hexadecimal addresses are specified on the command line, |
| and @code{addr2line} displays the file name and line number for each |
| address. |
| |
| In the second, @code{addr2line} reads hexadecimal addresses from |
| standard input, and prints the file name and line number for each |
| address on standard output. In this mode, @code{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 |
| @code{-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, |
| @code{addr2line} will print two question marks in their place. If the |
| line number can not be determined, @code{addr2line} will print 0. |
| |
| The long and short forms of options, shown here as alternatives, are |
| equivalent. |
| |
| @table @code |
| @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 |
| @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. @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. |
| @end table |
| |
| @node nlmconv |
| @chapter nlmconv |
| |
| @code{nlmconv} converts a relocatable object file into a NetWare |
| Loadable Module. |
| |
| @ignore |
| @code{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{ |
| @code{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:} @code{nlmconv} is not always built as part of the binary |
| utilities, since it is only useful for NLM targets. |
| @end quotation |
| |
| @smallexample |
| nlmconv [ -I @var{bfdname} | --input-target=@var{bfdname} ] |
| [ -O @var{bfdname} | --output-target=@var{bfdname} ] |
| [ -T @var{headerfile} | --header-file=@var{headerfile} ] |
| [ -d | --debug] [ -l @var{linker} | --linker=@var{linker} ] |
| [ -h | --help ] [ -V | --version ] |
| @var{infile} @var{outfile} |
| @end smallexample |
| |
| @code{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. |
| @code{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read |
| @var{infile}; see @ref{BFD,,BFD,ld.info,Using LD}, for |
| more information. |
| |
| @code{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, @code{nlmconv} calls the linker for you. |
| |
| @table @code |
| @item -I @var{bfdname} |
| @itemx --input-target=@var{bfdname} |
| Object format of the input file. @code{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. @code{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 @code{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 @code{nlmconv}. |
| @end table |
| |
| @node windres |
| @chapter windres |
| |
| @code{windres} may be used to manipulate Windows resources. |
| |
| @quotation |
| @emph{Warning:} @code{windres} is not always built as part of the binary |
| utilities, since it is only useful for Windows targets. |
| @end quotation |
| |
| @smallexample |
| windres [options] [input-file] [output-file] |
| @end smallexample |
| |
| @code{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 @code{windres} converts from the @code{rc} format to the @code{res} |
| format, it is acting like the Windows Resource Compiler. When |
| @code{windres} converts from the @code{res} format to the @code{coff} |
| format, it is acting like the Windows @code{CVTRES} program. |
| |
| When @code{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, @code{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, @code{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 @code{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. |
| |
| @table @code |
| @item -i @var{filename} |
| @itemx --input @var{filename} |
| The name of the input file. If this option is not used, then |
| @code{windres} will use the first non-option argument as the input file |
| name. If there are no non-option arguments, then @code{windres} will |
| read from standard input. @code{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 |
| @code{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 @code{windres} will write to standard output. |
| @code{windres} can not write a COFF file to standard output. |
| |
| @item -I @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, @code{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, |
| @code{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 @code{--help} option to see a list |
| of supported targets. Normally @code{windres} will use the default |
| format, which is the first one listed by the @code{--help} option. |
| @ref{Target Selection}. |
| |
| @item --preprocessor @var{program} |
| When @code{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 --include-dir @var{directory} |
| Specify an include directory to use when reading an @code{rc} file. |
| @code{windres} will pass this to the preprocessor as an @code{-I} |
| option. @code{windres} will also search this directory when looking for |
| files named in the @code{rc} file. |
| |
| @item -D @var{target} |
| @itemx --define @var{sym}[=@var{val}] |
| Specify a @code{-D} option to pass to the preprocessor when reading an |
| @code{rc} file. |
| |
| @item -v |
| Enable verbose mode. This tells you what the preprocessor is if you |
| didn't specify one. |
| |
| @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 --help |
| Prints a usage summary. |
| |
| @item --version |
| Prints the version number for @code{windres}. |
| |
| @item --yydebug |
| If @code{windres} is compiled with @code{YYDEBUG} defined as @code{1}, |
| this will turn on parser debugging. |
| @end table |
| |
| |
| @node dlltool |
| @chapter Create files needed to build and use DLLs |
| @cindex DLL |
| @kindex dlltool |
| |
| @code{dlltool} may be used to create the files needed to build and use |
| dynamic link libraries (DLLs). |
| |
| @quotation |
| @emph{Warning:} @code{dlltool} is not always built as part of the binary |
| utilities, since it is only useful for those targets which support DLLs. |
| @end quotation |
| |
| @smallexample |
| dlltool [-d|--input-def @var{def-file-name}] |
| [-b|--base-file @var{base-file-name}] |
| [-e|--output-exp @var{exports-file-name}] |
| [-z|--output-def @var{def-file-name}] |
| [-l|--output-lib @var{library-file-name}] |
| [--export-all-symbols] [--no-export-all-symbols] |
| [--exclude-symbols @var{list}] |
| [--no-default-excludes] |
| [-S|--as @var{path-to-assembler}] [-f|--as-flags @var{options}] |
| [-D|--dllname @var{name}] [-m|--machine @var{machine}] |
| [-a|--add-indirect] [-U|--add-underscore] [-k|--kill-at] |
| [-A|--add-stdcall-alias] |
| [-x|--no-idata4] [-c|--no-idata5] [-i|--interwork] |
| [-n|--nodelete] [-v|--verbose] [-h|--help] [-V|--version] |
| [object-file @dots{}] |
| @end smallexample |
| |
| @code{dlltool} reads its inputs, which can come from the @samp{-d} and |
| @samp{-b} options as well as object files specified on the command |
| line. It then processes these inputs and if the @samp{-e} option has |
| been specified it creates a exports file. If the @samp{-l} option |
| has been specified it creates a library file and if the @samp{-z} option |
| has been specified it creates a def file. Any or all of the -e, -l |
| and -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. @code{dlltool} can help with the creation of |
| these files. |
| |
| The first file is a @samp{.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 @code{dlltool} can be used |
| to create it using the @samp{-z} option. In this case @code{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 .def file it creates. |
| |
| In order to mark a function as being exported from a DLL, it needs to |
| have an @samp{-export:<name_of_function>} 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 @samp{-e} option to |
| @code{dlltool} when it is creating or reading in a .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 @samp{-l} option to dlltool when it |
| is creating or reading in a .def file. |
| |
| @code{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 @samp{-S} command line option can be |
| used to specify the path to the assembler that dlltool will use, |
| and the @samp{-f} option can be used to pass specific flags to that |
| assembler. The @samp{-n} can be used to prevent dlltool from deleting |
| these temporary assembler files when it is done, and if @samp{-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 |
| |
| The command line options have the following meanings: |
| |
| @table @code |
| |
| @item -d @var{filename} |
| @itemx --input-def @var{filename} |
| @cindex input .def file |
| Specifies the name of a .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 .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 @code{--no-default-excludes} |
| option. You may add to the list of symbols to not export by using the |
| @code{--exclude-symbols} option. |
| |
| @item --no-export-all-symbols |
| Only export symbols explicitly listed in an input .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 |
| @code{--export-all-symbols} is used. |
| |
| @item --no-default-excludes |
| When @code{--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 @code{--no-default-excludes} option |
| to go ahead and export these special symbols. This is only meaningful |
| when @code{--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{switches} |
| @itemx --as-flags @var{switches} |
| Specifies any specific command line switches to be passed to the |
| assembler when building the exports file. This option will work even if |
| the @samp{-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 switches 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 .def file as the name of the DLL |
| when the @samp{-e} option is used. If this option is not present, then |
| the filename given to the @samp{-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. @code{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 @code{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 @code{dlltool} is creating the exports file it |
| should prepend an underscore to the names of the exported functions. |
| |
| @item -k |
| @itemx --kill-at |
| Specifies that when @code{dlltool} is creating the exports file it |
| should not append the string @samp{@@ <number>}. 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 @code{dlltool} is creating the exports file it |
| should add aliases for stdcall symbols without @samp{@@ <number>} |
| in addition to the symbols with @samp{@@ <number>}. |
| |
| @item -x |
| @itemx --no-idata4 |
| Specifies that when @code{dlltool} is creating the exports and library |
| files it should omit the .idata4 section. This is for compatibility |
| with certain operating systems. |
| |
| @item -c |
| @itemx --no-idata5 |
| Specifies that when @code{dlltool} is creating the exports and library |
| files it should omit the .idata5 section. This is for compatibility |
| with certain operating systems. |
| |
| @item -i |
| @itemx --interwork |
| Specifies that @code{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 @code{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 -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 |
| |
| @node readelf |
| @chapter readelf |
| |
| @cindex ELF file information |
| @kindex readelf |
| |
| @smallexample |
| readelf [ -a | --all ] |
| [ -h | --file-header] |
| [ -l | --program-headers | --segments] |
| [ -S | --section-headers | --sections] |
| [ -e | --headers] |
| [ -s | --syms | --symbols] |
| [ -n | --notes] |
| [ -r | --relocs] |
| [ -d | --dynamic] |
| [ -V | --version-info] |
| [ -D | --use-dynamic] |
| [ -x <number> | --hex-dump=<number>] |
| [ -w[liapr] | --debug-dump[=info,=line,=abbrev,=pubnames,=ranges]] |
| [ --histogram] |
| [ -v | --version] |
| [ -H | --help] |
| @var{elffile}@dots{} |
| @end smallexample |
| |
| @code{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. At the |
| moment, @code{readelf} does not support examining archives, nor does it |
| support examing 64 bit ELF files. |
| |
| 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 @code |
| @item -a |
| @itemx --all |
| Equivalent to specifiying @samp{--file-header}, |
| @samp{--program-headers}, @samp{--sections}, @samp{--symbols}, |
| @samp{--relocs}, @samp{--dynamic}, @samp{--notes} and |
| @samp{--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 -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 @samp{-h -l -S}. |
| |
| @item -n |
| @itemx --notes |
| @cindex ELF core notes |
| Displays the contents of the NOTE segment, if it exists. |
| |
| @item -r |
| @itemx --relocs |
| @cindex ELF reloc information |
| Displays the contents of the file's relocation section, if it ha one. |
| |
| @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 -D |
| @itemx --use-dynamic |
| When displaying symbols, this option makes @code{readelf} use the |
| symblol table in the file's dynamic section, rather than the one in the |
| symbols section. |
| |
| @item -x <number> |
| @itemx --hex-dump=<number> |
| Displays the contents of the indicated section as a hexadecimal dump. |
| |
| @item -w[liapr] |
| @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=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 --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 -H |
| @itemx --help |
| Display the command line options understood by @code{readelf}. |
| |
| @end table |
| |
| |
| @node Selecting The Target System |
| @chapter Selecting the target system |
| |
| You can specify three aspects of the target system to the @sc{gnu} |
| binary file utilities, each in several ways: |
| |
| @itemize @bullet |
| @item |
| the target |
| |
| @item |
| the architecture |
| |
| @item |
| the linker emulation (which applies to the linker only) |
| @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 |
| @samp{--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:: |
| * Linker Emulation 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 @code{objdump} Target |
| |
| Ways to specify: |
| |
| @enumerate |
| @item |
| command line option: @samp{-b} or @samp{--target} |
| |
| @item |
| environment variable @code{GNUTARGET} |
| |
| @item |
| deduced from the input file |
| @end enumerate |
| |
| @subheading @code{objcopy} and @code{strip} Input Target |
| |
| Ways to specify: |
| |
| @enumerate |
| @item |
| command line options: @samp{-I} or @samp{--input-target}, or @samp{-F} or @samp{--target} |
| |
| @item |
| environment variable @code{GNUTARGET} |
| |
| @item |
| deduced from the input file |
| @end enumerate |
| |
| @subheading @code{objcopy} and @code{strip} Output Target |
| |
| Ways to specify: |
| |
| @enumerate |
| @item |
| command line options: @samp{-O} or @samp{--output-target}, or @samp{-F} or @samp{--target} |
| |
| @item |
| the input target (see ``@code{objcopy} and @code{strip} Input Target'' above) |
| |
| @item |
| environment variable @code{GNUTARGET} |
| |
| @item |
| deduced from the input file |
| @end enumerate |
| |
| @subheading @code{nm}, @code{size}, and @code{strings} Target |
| |
| Ways to specify: |
| |
| @enumerate |
| @item |
| command line option: @samp{--target} |
| |
| @item |
| environment variable @code{GNUTARGET} |
| |
| @item |
| deduced from the input file |
| @end enumerate |
| |
| @subheading Linker Input Target |
| |
| Ways to specify: |
| |
| @enumerate |
| @item |
| command line option: @samp{-b} or @samp{--format} |
| (@pxref{Options,,Options,ld.info,Using LD}) |
| |
| @item |
| script command @code{TARGET} |
| (@pxref{Option Commands,,Option Commands,ld.info,Using LD}) |
| |
| @item |
| environment variable @code{GNUTARGET} |
| (@pxref{Environment,,Environment,ld.info,Using LD}) |
| |
| @item |
| the default target of the selected linker emulation |
| (@pxref{Linker Emulation Selection}) |
| @end enumerate |
| |
| @subheading Linker Output Target |
| |
| Ways to specify: |
| |
| @enumerate |
| @item |
| command line option: @samp{-oformat} |
| (@pxref{Options,,Options,ld.info,Using LD}) |
| |
| @item |
| script command @code{OUTPUT_FORMAT} |
| (@pxref{Option Commands,,Option Commands,ld.info,Using LD}) |
| |
| @item |
| the linker input target (see ``Linker Input Target'' above) |
| @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 @code{objdump} Architecture |
| |
| Ways to specify: |
| |
| @enumerate |
| @item |
| command line option: @samp{-m} or @samp{--architecture} |
| |
| @item |
| deduced from the input file |
| @end enumerate |
| |
| @subheading @code{objcopy}, @code{nm}, @code{size}, @code{strings} Architecture |
| |
| Ways to specify: |
| |
| @enumerate |
| @item |
| deduced from the input file |
| @end enumerate |
| |
| @subheading Linker Input Architecture |
| |
| Ways to specify: |
| |
| @enumerate |
| @item |
| deduced from the input file |
| @end enumerate |
| |
| @subheading Linker Output Architecture |
| |
| Ways to specify: |
| |
| @enumerate |
| @item |
| script command @code{OUTPUT_ARCH} |
| (@pxref{Option Commands,,Option Commands,ld.info,Using LD}) |
| |
| @item |
| the default architecture from the linker output target |
| (@pxref{Target Selection}) |
| @end enumerate |
| |
| @node Linker Emulation Selection |
| @section Linker emulation selection |
| |
| A linker @dfn{emulation} is a ``personality'' of the linker, which gives |
| the linker default values for the other aspects of the target system. |
| In particular, it consists of |
| |
| @itemize @bullet |
| @item |
| the linker script |
| |
| @item |
| the target |
| |
| @item |
| several ``hook'' functions that are run at certain stages of the linking |
| process to do special things that some targets require |
| @end itemize |
| |
| The command to list valid linker emulation values is @samp{ld -V}. |
| |
| Sample values: @samp{hp300bsd}, @samp{mipslit}, @samp{sun4}. |
| |
| Ways to specify: |
| |
| @enumerate |
| @item |
| command line option: @samp{-m} |
| (@pxref{Options,,Options,ld.info,Using LD}) |
| |
| @item |
| environment variable @code{LDEMULATION} |
| |
| @item |
| compiled-in @code{DEFAULT_EMULATION} from @file{Makefile}, |
| which comes from @code{EMUL} in @file{config/@var{target}.mt} |
| @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-gnu-utils@@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?'' Those bug reports are useless, and we urge everyone to |
| @emph{refuse to respond to them} except to chide the sender to report |
| bugs properly. |
| |
| 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 @samp{--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-gnu-utils@@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., @code{gcc}, @code{gas}, and/or the @sc{gnu} @code{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 @code{gcc}, or |
| whatever, was used to produce the object files. Also say how |
| @code{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 @code{diff} with the @samp{-u}, @samp{-c}, or @samp{-p} |
| option. Always send diffs from the old file to the new file. If you |
| wish to discuss something in the @code{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 |
| |
| @node Index |
| @unnumbered Index |
| |
| @printindex cp |
| |
| @contents |
| @bye |