Provided by: binutils-common_2.34-6ubuntu1_amd64 bug


       nm - list symbols from object files


       nm [-A|-o|--print-file-name] [-a|--debug-syms]
          [-B|--format=bsd] [-C|--demangle[=style]]
          [-D|--dynamic] [-fformat|--format=format]
          [-g|--extern-only] [-h|--help]
          [-l|--line-numbers] [--inlines]
          [-P|--portability] [-p|--no-sort]
          [-r|--reverse-sort] [-S|--print-size]
          [-s|--print-armap] [-t radix|--radix=radix]
          [-u|--undefined-only] [-V|--version]
          [-X 32_64] [--defined-only] [--no-demangle]
          [--plugin name]
          [--size-sort] [--special-syms]
          [--synthetic] [--with-symbol-versions] [--target=bfdname]


       GNU nm lists the symbols from object files objfile....  If no object files are listed as
       arguments, nm assumes the file a.out.

       For each symbol, nm shows:

       •   The symbol value, in the radix selected by options (see below), or hexadecimal by

       •   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 usually local; if
           uppercase, the symbol is global (external).  There are however a few lowercase symbols
           that are shown for special global symbols ("u", "v" and "w").

           "A" The symbol's value is absolute, and will not be changed by further linking.

           "b" The symbol is in the BSS data section.  This section typically contains zero-
               initialized or uninitialized data, although the exact behavior is system

           "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.

           "d" The symbol is in the initialized data section.

           "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.

           "i" For PE format files this indicates that the symbol is in a section specific to the
               implementation of DLLs.  For ELF format files this indicates that the symbol is an
               indirect function.  This is a GNU extension to the standard set of ELF symbol
               types.  It indicates a symbol which if referenced by a relocation does not
               evaluate to its address, but instead must be invoked at runtime.  The runtime
               execution will then return the value to be used in the relocation.

           "I" The symbol is an indirect reference to another symbol.

           "N" The symbol is a debugging symbol.

           "n" The symbol is in the read-only data section.

           "p" The symbol is in a stack unwind section.

           "r" The symbol is in a read only data section.

           "s" The symbol is in an uninitialized or zero-initialized data section for small

           "t" The symbol is in the text (code) section.

           "U" The symbol is undefined.

           "u" The symbol is a unique global symbol.  This is a GNU extension to the standard set
               of ELF symbol bindings.  For such a symbol the dynamic linker will make sure that
               in the entire process there is just one symbol with this name and type in use.

           "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.  On some systems, uppercase indicates that a
               default value has been specified.

           "w" The symbol is a weak symbol that has not been specifically tagged as a weak object
               symbol.  When a weak defined symbol is linked with a normal defined symbol, the
               normal defined symbol is used with no error.  When a weak undefined symbol is
               linked and the symbol is not defined, the value of the symbol is determined in a
               system-specific manner without error.  On some systems, uppercase indicates that a
               default value has been specified.

           "-" 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.

           "?" The symbol type is unknown, or object file format specific.

       •   The symbol name.


       The long and short forms of options, shown here as alternatives, are equivalent.

           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.

           Display all symbols, even debugger-only symbols; normally these are not listed.

       -B  The same as --format=bsd (for compatibility with the MIPS nm).

           Decode (demangle) low-level symbol names into user-level names.  Besides removing any
           initial underscore prepended by the system, this makes C++ function names readable.
           Different compilers have different mangling styles. The optional demangling style
           argument can be used to choose an appropriate demangling style for your compiler.

           Do not demangle low-level symbol names.  This is the default.

           Enables or disables a limit on the amount of recursion performed whilst demangling
           strings.  Since the name mangling formats allow for an inifinite level of recursion it
           is possible to create strings whose decoding will exhaust the amount of stack space
           available on the host machine, triggering a memory fault.  The limit tries to prevent
           this from happening by restricting recursion to 2048 levels of nesting.

           The default is for this limit to be enabled, but disabling it may be necessary in
           order to demangle truly complicated names.  Note however that if the recursion limit
           is disabled then stack exhaustion is possible and any bug reports about such an event
           will be rejected.

           Display the dynamic symbols rather than the normal symbols.  This is only meaningful
           for dynamic objects, such as certain types of shared libraries.

       -f format
           Use the output format format, which can be "bsd", "sysv", or "posix".  The default is
           "bsd".  Only the first character of format is significant; it can be either upper or
           lower case.

           Display only external symbols.

           Show a summary of the options to nm and exit.

           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

           When option -l is active, if the address belongs to a function that was inlined, then
           this option causes the source information for all enclosing scopes back to the first
           non-inlined function to be printed as well.  For example, if "main" inlines "callee1"
           which inlines "callee2", and address is from "callee2", the source information for
           "callee1" and "main" will also be printed.

           Sort symbols numerically by their addresses, rather than alphabetically by their

           Do not bother to sort the symbols in any order; print them in the order encountered.

           Use the POSIX.2 standard output format instead of the default format.  Equivalent to
           -f posix.

           Reverse the order of the sort (whether numeric or alphabetic); let the last come

           Print both value and size of defined symbols for the "bsd" output style.  This option
           has no effect for object formats that do not record symbol sizes, unless --size-sort
           is also used in which case a calculated size is displayed.

           When listing symbols from archive members, include the index: a mapping (stored in the
           archive by ar or ranlib) of which modules contain definitions for which names.

       -t radix
           Use radix as the radix for printing the symbol values.  It must be d for decimal, o
           for octal, or x for hexadecimal.

           Display only undefined symbols (those external to each object file).

           Show the version number of nm and exit.

       -X  This option is ignored for compatibility with the AIX version of nm.  It takes one
           parameter which must be the string 32_64.  The default mode of AIX nm corresponds to
           -X 32, which is not supported by GNU nm.

           Display only defined symbols for each object file.

       --plugin name
           Load the plugin called name to add support for extra target types.  This option is
           only available if the toolchain has been built with plugin support enabled.

           If --plugin is not provided, but plugin support has been enabled then nm iterates over
           the files in ${libdir}/bfd-plugins in alphabetic order and the first plugin that
           claims the object in question is used.

           Please note that this plugin search directory is not the one used by ld's -plugin
           option.  In order to make nm use the  linker plugin it must be copied into the
           ${libdir}/bfd-plugins directory.  For GCC based compilations the linker plugin is
           called  For Clang based compilations it is called
           The GCC plugin is always backwards compatible with earlier versions, so it is
           sufficient to just copy the newest one.

           Sort symbols by size.  For ELF objects symbol sizes are read from the ELF, for other
           object types the symbol sizes are computed as the difference between the value of the
           symbol and the value of the symbol with the next higher value.  If the "bsd" output
           format is used the size of the symbol is printed, rather than the value, and -S must
           be used in order both size and value to be printed.

           Display symbols which have a target-specific special meaning.  These symbols are
           usually used by the target for some special processing and are not normally helpful
           when included in the normal symbol lists.  For example for ARM targets this option
           would skip the mapping symbols used to mark transitions between ARM code, THUMB code
           and data.

           Include synthetic symbols in the output.  These are special symbols created by the
           linker for various purposes.  They are not shown by default since they are not part of
           the binary's original source code.

           Enables the display of symbol version information if any exists.  The version string
           is displayed as a suffix to the symbol name, preceeded by an @ character.  For example
           foo@VER_1.  If the version is the default version to be used when resolving
           unversioned references to the symbol then it is displayed as a suffix preceeded by two
           @ characters.  For example foo@@VER_2.

           Specify an object code format other than your system's default format.

           Read command-line options from file.  The options read are inserted in place of the
           original @file option.  If file does not exist, or cannot be read, then the option
           will be treated literally, and not removed.

           Options in file are separated by whitespace.  A whitespace character may be included
           in an option by surrounding the entire option in either single or double quotes.  Any
           character (including a backslash) may be included by prefixing the character to be
           included with a backslash.  The file may itself contain additional @file options; any
           such options will be processed recursively.


       ar(1), objdump(1), ranlib(1), and the Info entries for binutils.


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