| <html lang="en"> |
| <head> |
| <title>objcopy - GNU Binary Utilities</title> |
| <meta http-equiv="Content-Type" content="text/html"> |
| <meta name="description" content="GNU Binary Utilities"> |
| <meta name="generator" content="makeinfo 4.13"> |
| <link title="Top" rel="start" href="index.html#Top"> |
| <link rel="prev" href="nm.html#nm" title="nm"> |
| <link rel="next" href="objdump.html#objdump" title="objdump"> |
| <link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> |
| <!-- |
| Copyright (C) 1991-2019 Free Software Foundation, Inc. |
| |
| Permission is granted to copy, distribute and/or modify this document |
| under the terms of the GNU Free Documentation License, Version 1.3 |
| or any later version published by the Free Software Foundation; |
| with no Invariant Sections, with no Front-Cover Texts, and with no |
| Back-Cover Texts. A copy of the license is included in the |
| section entitled ``GNU Free Documentation License''. |
| |
| --> |
| <meta http-equiv="Content-Style-Type" content="text/css"> |
| <style type="text/css"><!-- |
| pre.display { font-family:inherit } |
| pre.format { font-family:inherit } |
| pre.smalldisplay { font-family:inherit; font-size:smaller } |
| pre.smallformat { font-family:inherit; font-size:smaller } |
| pre.smallexample { font-size:smaller } |
| pre.smalllisp { font-size:smaller } |
| span.sc { font-variant:small-caps } |
| span.roman { font-family:serif; font-weight:normal; } |
| span.sansserif { font-family:sans-serif; font-weight:normal; } |
| --></style> |
| </head> |
| <body> |
| <div class="node"> |
| <a name="objcopy"></a> |
| <p> |
| Next: <a rel="next" accesskey="n" href="objdump.html#objdump">objdump</a>, |
| Previous: <a rel="previous" accesskey="p" href="nm.html#nm">nm</a>, |
| Up: <a rel="up" accesskey="u" href="index.html#Top">Top</a> |
| <hr> |
| </div> |
| |
| <h2 class="chapter">3 objcopy</h2> |
| |
| <!-- man title objcopy copy and translate object files --> |
| <pre class="smallexample"> <!-- man begin SYNOPSIS objcopy --> |
| objcopy [<samp><span class="option">-F</span></samp> <var>bfdname</var>|<samp><span class="option">--target=</span></samp><var>bfdname</var>] |
| [<samp><span class="option">-I</span></samp> <var>bfdname</var>|<samp><span class="option">--input-target=</span></samp><var>bfdname</var>] |
| [<samp><span class="option">-O</span></samp> <var>bfdname</var>|<samp><span class="option">--output-target=</span></samp><var>bfdname</var>] |
| [<samp><span class="option">-B</span></samp> <var>bfdarch</var>|<samp><span class="option">--binary-architecture=</span></samp><var>bfdarch</var>] |
| [<samp><span class="option">-S</span></samp>|<samp><span class="option">--strip-all</span></samp>] |
| [<samp><span class="option">-g</span></samp>|<samp><span class="option">--strip-debug</span></samp>] |
| [<samp><span class="option">--strip-unneeded</span></samp>] |
| [<samp><span class="option">-K</span></samp> <var>symbolname</var>|<samp><span class="option">--keep-symbol=</span></samp><var>symbolname</var>] |
| [<samp><span class="option">-N</span></samp> <var>symbolname</var>|<samp><span class="option">--strip-symbol=</span></samp><var>symbolname</var>] |
| [<samp><span class="option">--strip-unneeded-symbol=</span></samp><var>symbolname</var>] |
| [<samp><span class="option">-G</span></samp> <var>symbolname</var>|<samp><span class="option">--keep-global-symbol=</span></samp><var>symbolname</var>] |
| [<samp><span class="option">--localize-hidden</span></samp>] |
| [<samp><span class="option">-L</span></samp> <var>symbolname</var>|<samp><span class="option">--localize-symbol=</span></samp><var>symbolname</var>] |
| [<samp><span class="option">--globalize-symbol=</span></samp><var>symbolname</var>] |
| [<samp><span class="option">--globalize-symbols=</span></samp><var>filename</var>] |
| [<samp><span class="option">-W</span></samp> <var>symbolname</var>|<samp><span class="option">--weaken-symbol=</span></samp><var>symbolname</var>] |
| [<samp><span class="option">-w</span></samp>|<samp><span class="option">--wildcard</span></samp>] |
| [<samp><span class="option">-x</span></samp>|<samp><span class="option">--discard-all</span></samp>] |
| [<samp><span class="option">-X</span></samp>|<samp><span class="option">--discard-locals</span></samp>] |
| [<samp><span class="option">-b</span></samp> <var>byte</var>|<samp><span class="option">--byte=</span></samp><var>byte</var>] |
| [<samp><span class="option">-i</span></samp> [<var>breadth</var>]|<samp><span class="option">--interleave</span></samp>[=<var>breadth</var>]] |
| [<samp><span class="option">--interleave-width=</span></samp><var>width</var>] |
| [<samp><span class="option">-j</span></samp> <var>sectionpattern</var>|<samp><span class="option">--only-section=</span></samp><var>sectionpattern</var>] |
| [<samp><span class="option">-R</span></samp> <var>sectionpattern</var>|<samp><span class="option">--remove-section=</span></samp><var>sectionpattern</var>] |
| [<samp><span class="option">--remove-relocations=</span></samp><var>sectionpattern</var>] |
| [<samp><span class="option">-p</span></samp>|<samp><span class="option">--preserve-dates</span></samp>] |
| [<samp><span class="option">-D</span></samp>|<samp><span class="option">--enable-deterministic-archives</span></samp>] |
| [<samp><span class="option">-U</span></samp>|<samp><span class="option">--disable-deterministic-archives</span></samp>] |
| [<samp><span class="option">--debugging</span></samp>] |
| [<samp><span class="option">--gap-fill=</span></samp><var>val</var>] |
| [<samp><span class="option">--pad-to=</span></samp><var>address</var>] |
| [<samp><span class="option">--set-start=</span></samp><var>val</var>] |
| [<samp><span class="option">--adjust-start=</span></samp><var>incr</var>] |
| [<samp><span class="option">--change-addresses=</span></samp><var>incr</var>] |
| [<samp><span class="option">--change-section-address</span></samp> <var>sectionpattern</var>{=,+,-}<var>val</var>] |
| [<samp><span class="option">--change-section-lma</span></samp> <var>sectionpattern</var>{=,+,-}<var>val</var>] |
| [<samp><span class="option">--change-section-vma</span></samp> <var>sectionpattern</var>{=,+,-}<var>val</var>] |
| [<samp><span class="option">--change-warnings</span></samp>] [<samp><span class="option">--no-change-warnings</span></samp>] |
| [<samp><span class="option">--set-section-flags</span></samp> <var>sectionpattern</var>=<var>flags</var>] |
| [<samp><span class="option">--set-section-alignment</span></samp> <var>sectionpattern</var>=<var>align</var>] |
| [<samp><span class="option">--add-section</span></samp> <var>sectionname</var>=<var>filename</var>] |
| [<samp><span class="option">--dump-section</span></samp> <var>sectionname</var>=<var>filename</var>] |
| [<samp><span class="option">--update-section</span></samp> <var>sectionname</var>=<var>filename</var>] |
| [<samp><span class="option">--rename-section</span></samp> <var>oldname</var>=<var>newname</var>[,<var>flags</var>]] |
| [<samp><span class="option">--long-section-names</span></samp> {enable,disable,keep}] |
| [<samp><span class="option">--change-leading-char</span></samp>] [<samp><span class="option">--remove-leading-char</span></samp>] |
| [<samp><span class="option">--reverse-bytes=</span></samp><var>num</var>] |
| [<samp><span class="option">--srec-len=</span></samp><var>ival</var>] [<samp><span class="option">--srec-forceS3</span></samp>] |
| [<samp><span class="option">--redefine-sym</span></samp> <var>old</var>=<var>new</var>] |
| [<samp><span class="option">--redefine-syms=</span></samp><var>filename</var>] |
| [<samp><span class="option">--weaken</span></samp>] |
| [<samp><span class="option">--keep-symbols=</span></samp><var>filename</var>] |
| [<samp><span class="option">--strip-symbols=</span></samp><var>filename</var>] |
| [<samp><span class="option">--strip-unneeded-symbols=</span></samp><var>filename</var>] |
| [<samp><span class="option">--keep-global-symbols=</span></samp><var>filename</var>] |
| [<samp><span class="option">--localize-symbols=</span></samp><var>filename</var>] |
| [<samp><span class="option">--weaken-symbols=</span></samp><var>filename</var>] |
| [<samp><span class="option">--add-symbol</span></samp> <var>name</var>=[<var>section</var>:]<var>value</var>[,<var>flags</var>]] |
| [<samp><span class="option">--alt-machine-code=</span></samp><var>index</var>] |
| [<samp><span class="option">--prefix-symbols=</span></samp><var>string</var>] |
| [<samp><span class="option">--prefix-sections=</span></samp><var>string</var>] |
| [<samp><span class="option">--prefix-alloc-sections=</span></samp><var>string</var>] |
| [<samp><span class="option">--add-gnu-debuglink=</span></samp><var>path-to-file</var>] |
| [<samp><span class="option">--keep-file-symbols</span></samp>] |
| [<samp><span class="option">--only-keep-debug</span></samp>] |
| [<samp><span class="option">--strip-dwo</span></samp>] |
| [<samp><span class="option">--extract-dwo</span></samp>] |
| [<samp><span class="option">--extract-symbol</span></samp>] |
| [<samp><span class="option">--writable-text</span></samp>] |
| [<samp><span class="option">--readonly-text</span></samp>] |
| [<samp><span class="option">--pure</span></samp>] |
| [<samp><span class="option">--impure</span></samp>] |
| [<samp><span class="option">--file-alignment=</span></samp><var>num</var>] |
| [<samp><span class="option">--heap=</span></samp><var>size</var>] |
| [<samp><span class="option">--image-base=</span></samp><var>address</var>] |
| [<samp><span class="option">--section-alignment=</span></samp><var>num</var>] |
| [<samp><span class="option">--stack=</span></samp><var>size</var>] |
| [<samp><span class="option">--subsystem=</span></samp><var>which</var>:<var>major</var>.<var>minor</var>] |
| [<samp><span class="option">--compress-debug-sections</span></samp>] |
| [<samp><span class="option">--decompress-debug-sections</span></samp>] |
| [<samp><span class="option">--elf-stt-common=</span><var>val</var></samp>] |
| [<samp><span class="option">--merge-notes</span></samp>] |
| [<samp><span class="option">--no-merge-notes</span></samp>] |
| [<samp><span class="option">--verilog-data-width=</span><var>val</var></samp>] |
| [<samp><span class="option">-v</span></samp>|<samp><span class="option">--verbose</span></samp>] |
| [<samp><span class="option">-V</span></samp>|<samp><span class="option">--version</span></samp>] |
| [<samp><span class="option">--help</span></samp>] [<samp><span class="option">--info</span></samp>] |
| <var>infile</var> [<var>outfile</var>] |
| <!-- man end --> |
| </pre> |
| <!-- man begin DESCRIPTION objcopy --> |
| <p>The <span class="sc">gnu</span> <samp><span class="command">objcopy</span></samp> utility copies the contents of an object |
| file to another. <samp><span class="command">objcopy</span></samp> uses the <span class="sc">gnu</span> <span class="sc">bfd</span> 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 <samp><span class="command">objcopy</span></samp> is controlled by command-line options. |
| Note that <samp><span class="command">objcopy</span></samp> should be able to copy a fully linked file |
| between any two formats. However, copying a relocatable object file |
| between any two formats may not work as expected. |
| |
| <p><samp><span class="command">objcopy</span></samp> creates temporary files to do its translations and |
| deletes them afterward. <samp><span class="command">objcopy</span></samp> uses <span class="sc">bfd</span> to do all its |
| translation work; it has access to all the formats described in <span class="sc">bfd</span> |
| and thus is able to recognize most formats without being told |
| explicitly. See <a href="../ld/BFD.html#BFD">BFD</a>. |
| |
| <p><samp><span class="command">objcopy</span></samp> can be used to generate S-records by using an output |
| target of ‘<samp><span class="samp">srec</span></samp>’ (e.g., use ‘<samp><span class="samp">-O srec</span></samp>’). |
| |
| <p><samp><span class="command">objcopy</span></samp> can be used to generate a raw binary file by using an |
| output target of ‘<samp><span class="samp">binary</span></samp>’ (e.g., use <samp><span class="option">-O binary</span></samp>). When |
| <samp><span class="command">objcopy</span></samp> 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. |
| |
| <p>When generating an S-record or a raw binary file, it may be helpful to |
| use <samp><span class="option">-S</span></samp> to remove sections containing debugging information. In |
| some cases <samp><span class="option">-R</span></samp> will be useful to remove sections which contain |
| information that is not needed by the binary file. |
| |
| <p>Note—<samp><span class="command">objcopy</span></samp> is not able to change the endianness of its input |
| files. If the input format has an endianness (some formats do not), |
| <samp><span class="command">objcopy</span></samp> can only copy the inputs into file formats that have the |
| same endianness or which have no endianness (e.g., ‘<samp><span class="samp">srec</span></samp>’). |
| (However, see the <samp><span class="option">--reverse-bytes</span></samp> option.) |
| |
| <!-- man end --> |
| <!-- man begin OPTIONS objcopy --> |
| <dl> |
| <dt><samp><var>infile</var></samp><dt><samp><var>outfile</var></samp><dd>The input and output files, respectively. |
| If you do not specify <var>outfile</var>, <samp><span class="command">objcopy</span></samp> creates a |
| temporary file and destructively renames the result with |
| the name of <var>infile</var>. |
| |
| <br><dt><samp><span class="env">-I </span><var>bfdname</var></samp><dt><samp><span class="env">--input-target=</span><var>bfdname</var></samp><dd>Consider the source file's object format to be <var>bfdname</var>, rather than |
| attempting to deduce it. See <a href="Target-Selection.html#Target-Selection">Target Selection</a>, for more information. |
| |
| <br><dt><samp><span class="env">-O </span><var>bfdname</var></samp><dt><samp><span class="env">--output-target=</span><var>bfdname</var></samp><dd>Write the output file using the object format <var>bfdname</var>. |
| See <a href="Target-Selection.html#Target-Selection">Target Selection</a>, for more information. |
| |
| <br><dt><samp><span class="env">-F </span><var>bfdname</var></samp><dt><samp><span class="env">--target=</span><var>bfdname</var></samp><dd>Use <var>bfdname</var> as the object format for both the input and the output |
| file; i.e., simply transfer data from source to destination with no |
| translation. See <a href="Target-Selection.html#Target-Selection">Target Selection</a>, for more information. |
| |
| <br><dt><samp><span class="env">-B </span><var>bfdarch</var></samp><dt><samp><span class="env">--binary-architecture=</span><var>bfdarch</var></samp><dd>Useful when transforming a architecture-less input file into an object file. |
| In this case the output architecture can be set to <var>bfdarch</var>. This |
| option will be ignored if the input file has a known <var>bfdarch</var>. You |
| can access this binary data inside a program by referencing the special |
| symbols that are created by the conversion process. These symbols are |
| called _binary_<var>objfile</var>_start, _binary_<var>objfile</var>_end and |
| _binary_<var>objfile</var>_size. e.g. you can transform a picture file into |
| an object file and then access it in your code using these symbols. |
| |
| <br><dt><samp><span class="env">-j </span><var>sectionpattern</var></samp><dt><samp><span class="env">--only-section=</span><var>sectionpattern</var></samp><dd>Copy only the indicated sections 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. Wildcard |
| characters are accepted in <var>sectionpattern</var>. |
| |
| <p>If the first character of <var>sectionpattern</var> is the exclamation |
| point (!) then matching sections will not be copied, even if earlier |
| use of <samp><span class="option">--only-section</span></samp> on the same command line would |
| otherwise copy it. For example: |
| |
| <pre class="smallexample"> --only-section=.text.* --only-section=!.text.foo |
| </pre> |
| <p>will copy all sectinos maching '.text.*' but not the section |
| '.text.foo'. |
| |
| <br><dt><samp><span class="env">-R </span><var>sectionpattern</var></samp><dt><samp><span class="env">--remove-section=</span><var>sectionpattern</var></samp><dd>Remove any section matching <var>sectionpattern</var> from the output file. |
| This option may be given more than once. Note that using this option |
| inappropriately may make the output file unusable. Wildcard |
| characters are accepted in <var>sectionpattern</var>. Using both the |
| <samp><span class="option">-j</span></samp> and <samp><span class="option">-R</span></samp> options together results in undefined |
| behaviour. |
| |
| <p>If the first character of <var>sectionpattern</var> is the exclamation |
| point (!) then matching sections will not be removed even if an |
| earlier use of <samp><span class="option">--remove-section</span></samp> on the same command line |
| would otherwise remove it. For example: |
| |
| <pre class="smallexample"> --remove-section=.text.* --remove-section=!.text.foo |
| </pre> |
| <p>will remove all sections matching the pattern '.text.*', but will not |
| remove the section '.text.foo'. |
| |
| <br><dt><samp><span class="env">--remove-relocations=</span><var>sectionpattern</var></samp><dd>Remove non-dynamic relocations from the output file for any section |
| matching <var>sectionpattern</var>. This option may be given more than |
| once. Note that using this option inappropriately may make the output |
| file unusable, and attempting to remove a dynamic relocation section |
| such as ‘<samp><span class="samp">.rela.plt</span></samp>’ from an executable or shared library with |
| <samp><span class="option">--remove-relocations=.plt</span></samp> will not work. Wildcard characters |
| are accepted in <var>sectionpattern</var>. |
| For example: |
| |
| <pre class="smallexample"> --remove-relocations=.text.* |
| </pre> |
| <p>will remove the relocations for all sections matching the pattern |
| '.text.*'. |
| |
| <p>If the first character of <var>sectionpattern</var> is the exclamation |
| point (!) then matching sections will not have their relocation |
| removed even if an earlier use of <samp><span class="option">--remove-relocations</span></samp> on the |
| same command line would otherwise cause the relocations to be removed. |
| For example: |
| |
| <pre class="smallexample"> --remove-relocations=.text.* --remove-relocations=!.text.foo |
| </pre> |
| <p>will remove all relocations for sections matching the pattern |
| '.text.*', but will not remove relocations for the section |
| '.text.foo'. |
| |
| <br><dt><samp><span class="env">-S</span></samp><dt><samp><span class="env">--strip-all</span></samp><dd>Do not copy relocation and symbol information from the source file. |
| |
| <br><dt><samp><span class="env">-g</span></samp><dt><samp><span class="env">--strip-debug</span></samp><dd>Do not copy debugging symbols or sections from the source file. |
| |
| <br><dt><samp><span class="env">--strip-unneeded</span></samp><dd>Strip all symbols that are not needed for relocation processing. |
| |
| <br><dt><samp><span class="env">-K </span><var>symbolname</var></samp><dt><samp><span class="env">--keep-symbol=</span><var>symbolname</var></samp><dd>When stripping symbols, keep symbol <var>symbolname</var> even if it would |
| normally be stripped. This option may be given more than once. |
| |
| <br><dt><samp><span class="env">-N </span><var>symbolname</var></samp><dt><samp><span class="env">--strip-symbol=</span><var>symbolname</var></samp><dd>Do not copy symbol <var>symbolname</var> from the source file. This option |
| may be given more than once. |
| |
| <br><dt><samp><span class="env">--strip-unneeded-symbol=</span><var>symbolname</var></samp><dd>Do not copy symbol <var>symbolname</var> from the source file unless it is needed |
| by a relocation. This option may be given more than once. |
| |
| <br><dt><samp><span class="env">-G </span><var>symbolname</var></samp><dt><samp><span class="env">--keep-global-symbol=</span><var>symbolname</var></samp><dd>Keep only symbol <var>symbolname</var> global. Make all other symbols local |
| to the file, so that they are not visible externally. This option may |
| be given more than once. Note: this option cannot be used in |
| conjunction with the <samp><span class="option">--globalize-symbol</span></samp> or |
| <samp><span class="option">--globalize-symbols</span></samp> options. |
| |
| <br><dt><samp><span class="env">--localize-hidden</span></samp><dd>In an ELF object, mark all symbols that have hidden or internal visibility |
| as local. This option applies on top of symbol-specific localization options |
| such as <samp><span class="option">-L</span></samp>. |
| |
| <br><dt><samp><span class="env">-L </span><var>symbolname</var></samp><dt><samp><span class="env">--localize-symbol=</span><var>symbolname</var></samp><dd>Convert a global or weak symbol called <var>symbolname</var> into a local |
| symbol, so that it is not visible externally. This option may be |
| given more than once. Note - unique symbols are not converted. |
| |
| <br><dt><samp><span class="env">-W </span><var>symbolname</var></samp><dt><samp><span class="env">--weaken-symbol=</span><var>symbolname</var></samp><dd>Make symbol <var>symbolname</var> weak. This option may be given more than once. |
| |
| <br><dt><samp><span class="env">--globalize-symbol=</span><var>symbolname</var></samp><dd>Give symbol <var>symbolname</var> global scoping so that it is visible |
| outside of the file in which it is defined. This option may be given |
| more than once. Note: this option cannot be used in conjunction with |
| the <samp><span class="option">-G</span></samp> or <samp><span class="option">--keep-global-symbol</span></samp> options. |
| |
| <br><dt><samp><span class="env">-w</span></samp><dt><samp><span class="env">--wildcard</span></samp><dd>Permit regular expressions in <var>symbolname</var>s used in other command |
| line options. The question mark (?), asterisk (*), backslash (\) and |
| square brackets ([]) operators can be used anywhere in the symbol |
| name. If the first character of the symbol name is the exclamation |
| point (!) then the sense of the switch is reversed for that symbol. |
| For example: |
| |
| <pre class="smallexample"> -w -W !foo -W fo* |
| </pre> |
| <p>would cause objcopy to weaken all symbols that start with “fo” |
| except for the symbol “foo”. |
| |
| <br><dt><samp><span class="env">-x</span></samp><dt><samp><span class="env">--discard-all</span></samp><dd>Do not copy non-global symbols from the source file. |
| <!-- FIXME any reason to prefer "non-global" to "local" here? --> |
| |
| <br><dt><samp><span class="env">-X</span></samp><dt><samp><span class="env">--discard-locals</span></samp><dd>Do not copy compiler-generated local symbols. |
| (These usually start with ‘<samp><span class="samp">L</span></samp>’ or ‘<samp><span class="samp">.</span></samp>’.) |
| |
| <br><dt><samp><span class="env">-b </span><var>byte</var></samp><dt><samp><span class="env">--byte=</span><var>byte</var></samp><dd>If interleaving has been enabled via the <samp><span class="option">--interleave</span></samp> option |
| then start the range of bytes to keep at the <var>byte</var>th byte. |
| <var>byte</var> can be in the range from 0 to <var>breadth</var>-1, where |
| <var>breadth</var> is the value given by the <samp><span class="option">--interleave</span></samp> option. |
| |
| <br><dt><samp><span class="env">-i [</span><var>breadth</var><span class="env">]</span></samp><dt><samp><span class="env">--interleave[=</span><var>breadth</var><span class="env">]</span></samp><dd>Only copy a range out of every <var>breadth</var> bytes. (Header data is |
| not affected). Select which byte in the range begins the copy with |
| the <samp><span class="option">--byte</span></samp> option. Select the width of the range with the |
| <samp><span class="option">--interleave-width</span></samp> option. |
| |
| <p>This option is useful for creating files to program <span class="sc">rom</span>. It is |
| typically used with an <code>srec</code> output target. Note that |
| <samp><span class="command">objcopy</span></samp> will complain if you do not specify the |
| <samp><span class="option">--byte</span></samp> option as well. |
| |
| <p>The default interleave breadth is 4, so with <samp><span class="option">--byte</span></samp> set to 0, |
| <samp><span class="command">objcopy</span></samp> would copy the first byte out of every four bytes |
| from the input to the output. |
| |
| <br><dt><samp><span class="env">--interleave-width=</span><var>width</var></samp><dd>When used with the <samp><span class="option">--interleave</span></samp> option, copy <var>width</var> |
| bytes at a time. The start of the range of bytes to be copied is set |
| by the <samp><span class="option">--byte</span></samp> option, and the extent of the range is set with |
| the <samp><span class="option">--interleave</span></samp> option. |
| |
| <p>The default value for this option is 1. The value of <var>width</var> plus |
| the <var>byte</var> value set by the <samp><span class="option">--byte</span></samp> option must not exceed |
| the interleave breadth set by the <samp><span class="option">--interleave</span></samp> option. |
| |
| <p>This option can be used to create images for two 16-bit flashes interleaved |
| in a 32-bit bus by passing <samp><span class="option">-b 0 -i 4 --interleave-width=2</span></samp> |
| and <samp><span class="option">-b 2 -i 4 --interleave-width=2</span></samp> to two <samp><span class="command">objcopy</span></samp> |
| commands. If the input was '12345678' then the outputs would be |
| '1256' and '3478' respectively. |
| |
| <br><dt><samp><span class="env">-p</span></samp><dt><samp><span class="env">--preserve-dates</span></samp><dd>Set the access and modification dates of the output file to be the same |
| as those of the input file. |
| |
| <br><dt><samp><span class="env">-D</span></samp><dt><samp><span class="env">--enable-deterministic-archives</span></samp><dd><a name="index-deterministic-archives-61"></a><a name="index-g_t_002d_002denable_002ddeterministic_002darchives-62"></a>Operate in <em>deterministic</em> mode. When copying archive members |
| and writing the archive index, use zero for UIDs, GIDs, timestamps, |
| and use consistent file modes for all files. |
| |
| <p>If <samp><span class="file">binutils</span></samp> was configured with |
| <samp><span class="option">--enable-deterministic-archives</span></samp>, then this mode is on by default. |
| It can be disabled with the ‘<samp><span class="samp">-U</span></samp>’ option, below. |
| |
| <br><dt><samp><span class="env">-U</span></samp><dt><samp><span class="env">--disable-deterministic-archives</span></samp><dd><a name="index-deterministic-archives-63"></a><a name="index-g_t_002d_002denable_002ddeterministic_002darchives-64"></a>Do <em>not</em> operate in <em>deterministic</em> mode. This is the |
| inverse of the <samp><span class="option">-D</span></samp> option, above: when copying archive members |
| and writing the archive index, use their actual UID, GID, timestamp, |
| and file mode values. |
| |
| <p>This is the default unless <samp><span class="file">binutils</span></samp> was configured with |
| <samp><span class="option">--enable-deterministic-archives</span></samp>. |
| |
| <br><dt><samp><span class="env">--debugging</span></samp><dd>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. |
| |
| <br><dt><samp><span class="env">--gap-fill </span><var>val</var></samp><dd>Fill gaps between sections with <var>val</var>. This operation applies to |
| the <em>load address</em> (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</var>. |
| |
| <br><dt><samp><span class="env">--pad-to </span><var>address</var></samp><dd>Pad the output file up to the load address <var>address</var>. This is |
| done by increasing the size of the last section. The extra space is |
| filled in with the value specified by <samp><span class="option">--gap-fill</span></samp> (default zero). |
| |
| <br><dt><samp><span class="env">--set-start </span><var>val</var></samp><dd>Set the start address of the new file to <var>val</var>. Not all object file |
| formats support setting the start address. |
| |
| <br><dt><samp><span class="env">--change-start </span><var>incr</var></samp><dt><samp><span class="env">--adjust-start </span><var>incr</var></samp><dd><a name="index-changing-start-address-65"></a>Change the start address by adding <var>incr</var>. Not all object file |
| formats support setting the start address. |
| |
| <br><dt><samp><span class="env">--change-addresses </span><var>incr</var></samp><dt><samp><span class="env">--adjust-vma </span><var>incr</var></samp><dd><a name="index-changing-object-addresses-66"></a>Change the VMA and LMA addresses of all sections, as well as the start |
| address, by adding <var>incr</var>. 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. |
| |
| <br><dt><samp><span class="env">--change-section-address </span><var>sectionpattern</var><span class="env">{=,+,-}</span><var>val</var></samp><dt><samp><span class="env">--adjust-section-vma </span><var>sectionpattern</var><span class="env">{=,+,-}</span><var>val</var></samp><dd><a name="index-changing-section-address-67"></a>Set or change both the VMA address and the LMA address of any section |
| matching <var>sectionpattern</var>. If ‘<samp><span class="samp">=</span></samp>’ is used, the section |
| address is set to <var>val</var>. Otherwise, <var>val</var> is added to or |
| subtracted from the section address. See the comments under |
| <samp><span class="option">--change-addresses</span></samp>, above. If <var>sectionpattern</var> does not |
| match any sections in the input file, a warning will be issued, unless |
| <samp><span class="option">--no-change-warnings</span></samp> is used. |
| |
| <br><dt><samp><span class="env">--change-section-lma </span><var>sectionpattern</var><span class="env">{=,+,-}</span><var>val</var></samp><dd><a name="index-changing-section-LMA-68"></a>Set or change the LMA address of any sections matching |
| <var>sectionpattern</var>. 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><span class="samp">=</span></samp>’ |
| is used, the section address is set to <var>val</var>. Otherwise, |
| <var>val</var> is added to or subtracted from the section address. See the |
| comments under <samp><span class="option">--change-addresses</span></samp>, above. If |
| <var>sectionpattern</var> does not match any sections in the input file, a |
| warning will be issued, unless <samp><span class="option">--no-change-warnings</span></samp> is used. |
| |
| <br><dt><samp><span class="env">--change-section-vma </span><var>sectionpattern</var><span class="env">{=,+,-}</span><var>val</var></samp><dd><a name="index-changing-section-VMA-69"></a>Set or change the VMA address of any section matching |
| <var>sectionpattern</var>. 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><span class="samp">=</span></samp>’ is used, the section address is set to |
| <var>val</var>. Otherwise, <var>val</var> is added to or subtracted from the |
| section address. See the comments under <samp><span class="option">--change-addresses</span></samp>, |
| above. If <var>sectionpattern</var> does not match any sections in the |
| input file, a warning will be issued, unless |
| <samp><span class="option">--no-change-warnings</span></samp> is used. |
| |
| <br><dt><samp><span class="env">--change-warnings</span></samp><dt><samp><span class="env">--adjust-warnings</span></samp><dd>If <samp><span class="option">--change-section-address</span></samp> or <samp><span class="option">--change-section-lma</span></samp> or |
| <samp><span class="option">--change-section-vma</span></samp> is used, and the section pattern does not |
| match any sections, issue a warning. This is the default. |
| |
| <br><dt><samp><span class="env">--no-change-warnings</span></samp><dt><samp><span class="env">--no-adjust-warnings</span></samp><dd>Do not issue a warning if <samp><span class="option">--change-section-address</span></samp> or |
| <samp><span class="option">--adjust-section-lma</span></samp> or <samp><span class="option">--adjust-section-vma</span></samp> is used, even |
| if the section pattern does not match any sections. |
| |
| <br><dt><samp><span class="env">--set-section-flags </span><var>sectionpattern</var><span class="env">=</span><var>flags</var></samp><dd>Set the flags for any sections matching <var>sectionpattern</var>. The |
| <var>flags</var> argument is a comma separated string of flag names. The |
| recognized names are ‘<samp><span class="samp">alloc</span></samp>’, ‘<samp><span class="samp">contents</span></samp>’, ‘<samp><span class="samp">load</span></samp>’, |
| ‘<samp><span class="samp">noload</span></samp>’, ‘<samp><span class="samp">readonly</span></samp>’, ‘<samp><span class="samp">code</span></samp>’, ‘<samp><span class="samp">data</span></samp>’, ‘<samp><span class="samp">rom</span></samp>’, |
| ‘<samp><span class="samp">share</span></samp>’, and ‘<samp><span class="samp">debug</span></samp>’. You can set the ‘<samp><span class="samp">contents</span></samp>’ flag |
| for a section which does not have contents, but it is not meaningful |
| to clear the ‘<samp><span class="samp">contents</span></samp>’ flag of a section which does have |
| contents–just remove the section instead. Not all flags are |
| meaningful for all object file formats. |
| |
| <br><dt><samp><span class="env">--set-section-alignment </span><var>sectionpattern</var><span class="env">=</span><var>align</var></samp><dd>Set the alignment for any sections matching <var>sectionpattern</var>. |
| <var>align</var> specifies the alignment in bytes and must be a power of |
| two, i.e. 1, 2, 4, 8<small class="dots">...</small>. |
| |
| <br><dt><samp><span class="env">--add-section </span><var>sectionname</var><span class="env">=</span><var>filename</var></samp><dd>Add a new section named <var>sectionname</var> while copying the file. The |
| contents of the new section are taken from the file <var>filename</var>. 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. |
| Note - it may be necessary to use the <samp><span class="option">--set-section-flags</span></samp> |
| option to set the attributes of the newly created section. |
| |
| <br><dt><samp><span class="env">--dump-section </span><var>sectionname</var><span class="env">=</span><var>filename</var></samp><dd>Place the contents of section named <var>sectionname</var> into the file |
| <var>filename</var>, overwriting any contents that may have been there |
| previously. This option is the inverse of <samp><span class="option">--add-section</span></samp>. |
| This option is similar to the <samp><span class="option">--only-section</span></samp> option except |
| that it does not create a formatted file, it just dumps the contents |
| as raw binary data, without applying any relocations. The option can |
| be specified more than once. |
| |
| <br><dt><samp><span class="env">--update-section </span><var>sectionname</var><span class="env">=</span><var>filename</var></samp><dd>Replace the existing contents of a section named <var>sectionname</var> |
| with the contents of file <var>filename</var>. The size of the section |
| will be adjusted to the size of the file. The section flags for |
| <var>sectionname</var> will be unchanged. For ELF format files the section |
| to segment mapping will also remain unchanged, something which is not |
| possible using <samp><span class="option">--remove-section</span></samp> followed by |
| <samp><span class="option">--add-section</span></samp>. The option can be specified more than once. |
| |
| <p>Note - it is possible to use <samp><span class="option">--rename-section</span></samp> and |
| <samp><span class="option">--update-section</span></samp> to both update and rename a section from one |
| command line. In this case, pass the original section name to |
| <samp><span class="option">--update-section</span></samp>, and the original and new section names to |
| <samp><span class="option">--rename-section</span></samp>. |
| |
| <br><dt><samp><span class="env">--add-symbol </span><var>name</var><span class="env">=[</span><var>section</var><span class="env">:]</span><var>value</var><span class="env">[,</span><var>flags</var><span class="env">]</span></samp><dd>Add a new symbol named <var>name</var> while copying the file. This option may be |
| specified multiple times. If the <var>section</var> is given, the symbol will be |
| associated with and relative to that section, otherwise it will be an ABS |
| symbol. Specifying an undefined section will result in a fatal error. There |
| is no check for the value, it will be taken as specified. Symbol flags can |
| be specified and not all flags will be meaningful for all object file |
| formats. By default, the symbol will be global. The special flag |
| 'before=<var>othersym</var>' will insert the new symbol in front of the specified |
| <var>othersym</var>, otherwise the symbol(s) will be added at the end of the |
| symbol table in the order they appear. |
| |
| <br><dt><samp><span class="env">--rename-section </span><var>oldname</var><span class="env">=</span><var>newname</var><span class="env">[,</span><var>flags</var><span class="env">]</span></samp><dd>Rename a section from <var>oldname</var> to <var>newname</var>, optionally |
| changing the section's flags to <var>flags</var> in the process. This has |
| the advantage over using a linker script to perform the rename in that |
| the output stays as an object file and does not become a linked |
| executable. |
| |
| <p>This option is particularly helpful when the input format is binary, |
| since this will always create a section called .data. If for example, |
| you wanted instead to create a section called .rodata containing binary |
| data you could use the following command line to achieve it: |
| |
| <pre class="smallexample"> objcopy -I binary -O <output_format> -B <architecture> \ |
| --rename-section .data=.rodata,alloc,load,readonly,data,contents \ |
| <input_binary_file> <output_object_file> |
| </pre> |
| <br><dt><samp><span class="env">--long-section-names {enable,disable,keep}</span></samp><dd>Controls the handling of long section names when processing <code>COFF</code> |
| and <code>PE-COFF</code> object formats. The default behaviour, ‘<samp><span class="samp">keep</span></samp>’, |
| is to preserve long section names if any are present in the input file. |
| The ‘<samp><span class="samp">enable</span></samp>’ and ‘<samp><span class="samp">disable</span></samp>’ options forcibly enable or disable |
| the use of long section names in the output object; when ‘<samp><span class="samp">disable</span></samp>’ |
| is in effect, any long section names in the input object will be truncated. |
| The ‘<samp><span class="samp">enable</span></samp>’ option will only emit long section names if any are |
| present in the inputs; this is mostly the same as ‘<samp><span class="samp">keep</span></samp>’, but it |
| is left undefined whether the ‘<samp><span class="samp">enable</span></samp>’ option might force the |
| creation of an empty string table in the output file. |
| |
| <br><dt><samp><span class="env">--change-leading-char</span></samp><dd>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 <samp><span class="command">objcopy</span></samp> 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. |
| |
| <br><dt><samp><span class="env">--remove-leading-char</span></samp><dd>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 |
| <samp><span class="option">--change-leading-char</span></samp> because it always changes the symbol name |
| when appropriate, regardless of the object file format of the output |
| file. |
| |
| <br><dt><samp><span class="env">--reverse-bytes=</span><var>num</var></samp><dd>Reverse the bytes in a section with output contents. A section length must |
| be evenly divisible by the value given in order for the swap to be able to |
| take place. Reversing takes place before the interleaving is performed. |
| |
| <p>This option is used typically in generating ROM images for problematic |
| target systems. For example, on some target boards, the 32-bit words |
| fetched from 8-bit ROMs are re-assembled in little-endian byte order |
| regardless of the CPU byte order. Depending on the programming model, the |
| endianness of the ROM may need to be modified. |
| |
| <p>Consider a simple file with a section containing the following eight |
| bytes: <code>12345678</code>. |
| |
| <p>Using ‘<samp><span class="samp">--reverse-bytes=2</span></samp>’ for the above example, the bytes in the |
| output file would be ordered <code>21436587</code>. |
| |
| <p>Using ‘<samp><span class="samp">--reverse-bytes=4</span></samp>’ for the above example, the bytes in the |
| output file would be ordered <code>43218765</code>. |
| |
| <p>By using ‘<samp><span class="samp">--reverse-bytes=2</span></samp>’ for the above example, followed by |
| ‘<samp><span class="samp">--reverse-bytes=4</span></samp>’ on the output file, the bytes in the second |
| output file would be ordered <code>34127856</code>. |
| |
| <br><dt><samp><span class="env">--srec-len=</span><var>ival</var></samp><dd>Meaningful only for srec output. Set the maximum length of the Srecords |
| being produced to <var>ival</var>. This length covers both address, data and |
| crc fields. |
| |
| <br><dt><samp><span class="env">--srec-forceS3</span></samp><dd>Meaningful only for srec output. Avoid generation of S1/S2 records, |
| creating S3-only record format. |
| |
| <br><dt><samp><span class="env">--redefine-sym </span><var>old</var><span class="env">=</span><var>new</var></samp><dd>Change the name of a symbol <var>old</var>, to <var>new</var>. This can be useful |
| when one is trying link two things together for which you have no |
| source, and there are name collisions. |
| |
| <br><dt><samp><span class="env">--redefine-syms=</span><var>filename</var></samp><dd>Apply <samp><span class="option">--redefine-sym</span></samp> to each symbol pair "<var>old</var> <var>new</var>" |
| listed in the file <var>filename</var>. <var>filename</var> is simply a flat file, |
| with one symbol pair per line. Line comments may be introduced by the hash |
| character. This option may be given more than once. |
| |
| <br><dt><samp><span class="env">--weaken</span></samp><dd>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 <samp><span class="option">-R</span></samp> option to the linker. This option is only effective when |
| using an object file format which supports weak symbols. |
| |
| <br><dt><samp><span class="env">--keep-symbols=</span><var>filename</var></samp><dd>Apply <samp><span class="option">--keep-symbol</span></samp> option to each symbol listed in the file |
| <var>filename</var>. <var>filename</var> is simply a flat file, with one symbol |
| name per line. Line comments may be introduced by the hash character. |
| This option may be given more than once. |
| |
| <br><dt><samp><span class="env">--strip-symbols=</span><var>filename</var></samp><dd>Apply <samp><span class="option">--strip-symbol</span></samp> option to each symbol listed in the file |
| <var>filename</var>. <var>filename</var> is simply a flat file, with one symbol |
| name per line. Line comments may be introduced by the hash character. |
| This option may be given more than once. |
| |
| <br><dt><samp><span class="env">--strip-unneeded-symbols=</span><var>filename</var></samp><dd>Apply <samp><span class="option">--strip-unneeded-symbol</span></samp> option to each symbol listed in |
| the file <var>filename</var>. <var>filename</var> is simply a flat file, with one |
| symbol name per line. Line comments may be introduced by the hash |
| character. This option may be given more than once. |
| |
| <br><dt><samp><span class="env">--keep-global-symbols=</span><var>filename</var></samp><dd>Apply <samp><span class="option">--keep-global-symbol</span></samp> option to each symbol listed in the |
| file <var>filename</var>. <var>filename</var> is simply a flat file, with one |
| symbol name per line. Line comments may be introduced by the hash |
| character. This option may be given more than once. |
| |
| <br><dt><samp><span class="env">--localize-symbols=</span><var>filename</var></samp><dd>Apply <samp><span class="option">--localize-symbol</span></samp> option to each symbol listed in the file |
| <var>filename</var>. <var>filename</var> is simply a flat file, with one symbol |
| name per line. Line comments may be introduced by the hash character. |
| This option may be given more than once. |
| |
| <br><dt><samp><span class="env">--globalize-symbols=</span><var>filename</var></samp><dd>Apply <samp><span class="option">--globalize-symbol</span></samp> option to each symbol listed in the file |
| <var>filename</var>. <var>filename</var> is simply a flat file, with one symbol |
| name per line. Line comments may be introduced by the hash character. |
| This option may be given more than once. Note: this option cannot be |
| used in conjunction with the <samp><span class="option">-G</span></samp> or <samp><span class="option">--keep-global-symbol</span></samp> |
| options. |
| |
| <br><dt><samp><span class="env">--weaken-symbols=</span><var>filename</var></samp><dd>Apply <samp><span class="option">--weaken-symbol</span></samp> option to each symbol listed in the file |
| <var>filename</var>. <var>filename</var> is simply a flat file, with one symbol |
| name per line. Line comments may be introduced by the hash character. |
| This option may be given more than once. |
| |
| <br><dt><samp><span class="env">--alt-machine-code=</span><var>index</var></samp><dd>If the output architecture has alternate machine codes, use the |
| <var>index</var>th code instead of the default one. This is useful in case |
| a machine is assigned an official code and the tool-chain adopts the |
| new code, but other applications still depend on the original code |
| being used. For ELF based architectures if the <var>index</var> |
| alternative does not exist then the value is treated as an absolute |
| number to be stored in the e_machine field of the ELF header. |
| |
| <br><dt><samp><span class="env">--writable-text</span></samp><dd>Mark the output text as writable. This option isn't meaningful for all |
| object file formats. |
| |
| <br><dt><samp><span class="env">--readonly-text</span></samp><dd>Make the output text write protected. This option isn't meaningful for all |
| object file formats. |
| |
| <br><dt><samp><span class="env">--pure</span></samp><dd>Mark the output file as demand paged. This option isn't meaningful for all |
| object file formats. |
| |
| <br><dt><samp><span class="env">--impure</span></samp><dd>Mark the output file as impure. This option isn't meaningful for all |
| object file formats. |
| |
| <br><dt><samp><span class="env">--prefix-symbols=</span><var>string</var></samp><dd>Prefix all symbols in the output file with <var>string</var>. |
| |
| <br><dt><samp><span class="env">--prefix-sections=</span><var>string</var></samp><dd>Prefix all section names in the output file with <var>string</var>. |
| |
| <br><dt><samp><span class="env">--prefix-alloc-sections=</span><var>string</var></samp><dd>Prefix all the names of all allocated sections in the output file with |
| <var>string</var>. |
| |
| <br><dt><samp><span class="env">--add-gnu-debuglink=</span><var>path-to-file</var></samp><dd>Creates a .gnu_debuglink section which contains a reference to |
| <var>path-to-file</var> and adds it to the output file. Note: the file at |
| <var>path-to-file</var> must exist. Part of the process of adding the |
| .gnu_debuglink section involves embedding a checksum of the contents |
| of the debug info file into the section. |
| |
| <p>If the debug info file is built in one location but it is going to be |
| installed at a later time into a different location then do not use |
| the path to the installed location. The <samp><span class="option">--add-gnu-debuglink</span></samp> |
| option will fail because the installed file does not exist yet. |
| Instead put the debug info file in the current directory and use the |
| <samp><span class="option">--add-gnu-debuglink</span></samp> option without any directory components, |
| like this: |
| |
| <pre class="smallexample"> objcopy --add-gnu-debuglink=foo.debug |
| </pre> |
| <p>At debug time the debugger will attempt to look for the separate debug |
| info file in a set of known locations. The exact set of these |
| locations varies depending upon the distribution being used, but it |
| typically includes: |
| |
| <dl> |
| <dt><code>* The same directory as the executable.</code> |
| <br><dt><code>* A sub-directory of the directory containing the executable</code><dd>called .debug |
| |
| <br><dt><code>* A global debug directory such as /usr/lib/debug.</code><dd></dl> |
| |
| <p>As long as the debug info file has been installed into one of these |
| locations before the debugger is run everything should work |
| correctly. |
| |
| <br><dt><samp><span class="env">--keep-file-symbols</span></samp><dd>When stripping a file, perhaps with <samp><span class="option">--strip-debug</span></samp> or |
| <samp><span class="option">--strip-unneeded</span></samp>, retain any symbols specifying source file names, |
| which would otherwise get stripped. |
| |
| <br><dt><samp><span class="env">--only-keep-debug</span></samp><dd>Strip a file, removing contents of any sections that would not be |
| stripped by <samp><span class="option">--strip-debug</span></samp> and leaving the debugging sections |
| intact. In ELF files, this preserves all note sections in the output. |
| |
| <p>Note - the section headers of the stripped sections are preserved, |
| including their sizes, but the contents of the section are discarded. |
| The section headers are preserved so that other tools can match up the |
| debuginfo file with the real executable, even if that executable has |
| been relocated to a different address space. |
| |
| <p>The intention is that this option will be used in conjunction with |
| <samp><span class="option">--add-gnu-debuglink</span></samp> to create a two part executable. One a |
| stripped binary which will occupy less space in RAM and in a |
| distribution and the second a debugging information file which is only |
| needed if debugging abilities are required. The suggested procedure |
| to create these files is as follows: |
| |
| <ol type=1 start=1> |
| <li>Link the executable as normal. Assuming that it is called |
| <code>foo</code> then... |
| <li>Run <code>objcopy --only-keep-debug foo foo.dbg</code> to |
| create a file containing the debugging info. |
| <li>Run <code>objcopy --strip-debug foo</code> to create a |
| stripped executable. |
| <li>Run <code>objcopy --add-gnu-debuglink=foo.dbg foo</code> |
| to add a link to the debugging info into the stripped executable. |
| </ol> |
| |
| <p>Note—the choice of <code>.dbg</code> as an extension for the debug info |
| file is arbitrary. Also the <code>--only-keep-debug</code> step is |
| optional. You could instead do this: |
| |
| <ol type=1 start=1> |
| <li>Link the executable as normal. |
| <li>Copy <code>foo</code> to <code>foo.full</code> |
| <li>Run <code>objcopy --strip-debug foo</code> |
| <li>Run <code>objcopy --add-gnu-debuglink=foo.full foo</code> |
| </ol> |
| |
| <p>i.e., the file pointed to by the <samp><span class="option">--add-gnu-debuglink</span></samp> can be the |
| full executable. It does not have to be a file created by the |
| <samp><span class="option">--only-keep-debug</span></samp> switch. |
| |
| <p>Note—this switch is only intended for use on fully linked files. It |
| does not make sense to use it on object files where the debugging |
| information may be incomplete. Besides the gnu_debuglink feature |
| currently only supports the presence of one filename containing |
| debugging information, not multiple filenames on a one-per-object-file |
| basis. |
| |
| <br><dt><samp><span class="env">--strip-dwo</span></samp><dd>Remove the contents of all DWARF .dwo sections, leaving the |
| remaining debugging sections and all symbols intact. |
| This option is intended for use by the compiler as part of |
| the <samp><span class="option">-gsplit-dwarf</span></samp> option, which splits debug information |
| between the .o file and a separate .dwo file. The compiler |
| generates all debug information in the same file, then uses |
| the <samp><span class="option">--extract-dwo</span></samp> option to copy the .dwo sections to |
| the .dwo file, then the <samp><span class="option">--strip-dwo</span></samp> option to remove |
| those sections from the original .o file. |
| |
| <br><dt><samp><span class="env">--extract-dwo</span></samp><dd>Extract the contents of all DWARF .dwo sections. See the |
| <samp><span class="option">--strip-dwo</span></samp> option for more information. |
| |
| <br><dt><samp><span class="env">--file-alignment </span><var>num</var></samp><dd>Specify the file alignment. Sections in the file will always begin at |
| file offsets which are multiples of this number. This defaults to |
| 512. |
| [This option is specific to PE targets.] |
| |
| <br><dt><samp><span class="env">--heap </span><var>reserve</var></samp><dt><samp><span class="env">--heap </span><var>reserve</var><span class="env">,</span><var>commit</var></samp><dd>Specify the number of bytes of memory to reserve (and optionally commit) |
| to be used as heap for this program. |
| [This option is specific to PE targets.] |
| |
| <br><dt><samp><span class="env">--image-base </span><var>value</var></samp><dd>Use <var>value</var> as the base address of your program or dll. This is |
| the lowest memory location that will be used when your program or dll |
| is loaded. To reduce the need to relocate and improve performance of |
| your dlls, each should have a unique base address and not overlap any |
| other dlls. The default is 0x400000 for executables, and 0x10000000 |
| for dlls. |
| [This option is specific to PE targets.] |
| |
| <br><dt><samp><span class="env">--section-alignment </span><var>num</var></samp><dd>Sets the section alignment field in the PE header. Sections in memory |
| will always begin at addresses which are a multiple of this number. |
| Defaults to 0x1000. |
| [This option is specific to PE targets.] |
| |
| <br><dt><samp><span class="env">--stack </span><var>reserve</var></samp><dt><samp><span class="env">--stack </span><var>reserve</var><span class="env">,</span><var>commit</var></samp><dd>Specify the number of bytes of memory to reserve (and optionally commit) |
| to be used as stack for this program. |
| [This option is specific to PE targets.] |
| |
| <br><dt><samp><span class="env">--subsystem </span><var>which</var></samp><dt><samp><span class="env">--subsystem </span><var>which</var><span class="env">:</span><var>major</var></samp><dt><samp><span class="env">--subsystem </span><var>which</var><span class="env">:</span><var>major</var><span class="env">.</span><var>minor</var></samp><dd>Specifies the subsystem under which your program will execute. The |
| legal values for <var>which</var> are <code>native</code>, <code>windows</code>, |
| <code>console</code>, <code>posix</code>, <code>efi-app</code>, <code>efi-bsd</code>, |
| <code>efi-rtd</code>, <code>sal-rtd</code>, and <code>xbox</code>. You may optionally set |
| the subsystem version also. Numeric values are also accepted for |
| <var>which</var>. |
| [This option is specific to PE targets.] |
| |
| <br><dt><samp><span class="env">--extract-symbol</span></samp><dd>Keep the file's section flags and symbols but remove all section data. |
| Specifically, the option: |
| |
| <ul> |
| <li>removes the contents of all sections; |
| <li>sets the size of every section to zero; and |
| <li>sets the file's start address to zero. |
| </ul> |
| |
| <p>This option is used to build a <samp><span class="file">.sym</span></samp> file for a VxWorks kernel. |
| It can also be a useful way of reducing the size of a <samp><span class="option">--just-symbols</span></samp> |
| linker input file. |
| |
| <br><dt><samp><span class="env">--compress-debug-sections</span></samp><dd>Compress DWARF debug sections using zlib with SHF_COMPRESSED from the |
| ELF ABI. Note - if compression would actually make a section |
| <em>larger</em>, then it is not compressed. |
| |
| <br><dt><samp><span class="env">--compress-debug-sections=none</span></samp><dt><samp><span class="env">--compress-debug-sections=zlib</span></samp><dt><samp><span class="env">--compress-debug-sections=zlib-gnu</span></samp><dt><samp><span class="env">--compress-debug-sections=zlib-gabi</span></samp><dd>For ELF files, these options control how DWARF debug sections are |
| compressed. <samp><span class="option">--compress-debug-sections=none</span></samp> is equivalent |
| to <samp><span class="option">--decompress-debug-sections</span></samp>. |
| <samp><span class="option">--compress-debug-sections=zlib</span></samp> and |
| <samp><span class="option">--compress-debug-sections=zlib-gabi</span></samp> are equivalent to |
| <samp><span class="option">--compress-debug-sections</span></samp>. |
| <samp><span class="option">--compress-debug-sections=zlib-gnu</span></samp> compresses DWARF debug |
| sections using zlib. The debug sections are renamed to begin with |
| ‘<samp><span class="samp">.zdebug</span></samp>’ instead of ‘<samp><span class="samp">.debug</span></samp>’. Note - if compression would |
| actually make a section <em>larger</em>, then it is not compressed nor |
| renamed. |
| |
| <br><dt><samp><span class="env">--decompress-debug-sections</span></samp><dd>Decompress DWARF debug sections using zlib. The original section |
| names of the compressed sections are restored. |
| |
| <br><dt><samp><span class="env">--elf-stt-common=yes</span></samp><dt><samp><span class="env">--elf-stt-common=no</span></samp><dd>For ELF files, these options control whether common symbols should be |
| converted to the <code>STT_COMMON</code> or <code>STT_OBJECT</code> type. |
| <samp><span class="option">--elf-stt-common=yes</span></samp> converts common symbol type to |
| <code>STT_COMMON</code>. <samp><span class="option">--elf-stt-common=no</span></samp> converts common symbol |
| type to <code>STT_OBJECT</code>. |
| |
| <br><dt><samp><span class="env">--merge-notes</span></samp><dt><samp><span class="env">--no-merge-notes</span></samp><dd>For ELF files, attempt (or do not attempt) to reduce the size of any |
| SHT_NOTE type sections by removing duplicate notes. |
| |
| <br><dt><samp><span class="env">-V</span></samp><dt><samp><span class="env">--version</span></samp><dd>Show the version number of <samp><span class="command">objcopy</span></samp>. |
| |
| <br><dt><samp><span class="env">--verilog-data-width=</span><var>bytes</var></samp><dd>For Verilog output, this options controls the number of bytes |
| converted for each output data element. The input target controls the |
| endianness of the conversion. |
| |
| <br><dt><samp><span class="env">-v</span></samp><dt><samp><span class="env">--verbose</span></samp><dd>Verbose output: list all object files modified. In the case of |
| archives, ‘<samp><span class="samp">objcopy -V</span></samp>’ lists all members of the archive. |
| |
| <br><dt><samp><span class="env">--help</span></samp><dd>Show a summary of the options to <samp><span class="command">objcopy</span></samp>. |
| |
| <br><dt><samp><span class="env">--info</span></samp><dd>Display a list showing all architectures and object formats available. |
| </dl> |
| |
| <!-- man end --> |
| </body></html> |
| |