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C++FILT(1)                                      GNU Development Tools                                      C++FILT(1)



NAME
       c++filt - Demangle C++ and Java symbols.

SYNOPSIS
       c++filt [-_|--strip-underscore]
               [-n|--no-strip-underscore]
               [-p|--no-params]
               [-t|--types]
               [-i|--no-verbose]
               [-s format|--format=format]
               [--help]  [--version]  [symbol...]

DESCRIPTION
       The C++ and Java languages provide function overloading, which means that you can write many functions with
       the same name, providing that each function takes parameters of different types.  In order to be able to
       distinguish these similarly named functions C++ and Java encode them into a low-level assembler name which
       uniquely identifies each different version.  This process is known as mangling. The c++filt [1] program does
       the inverse mapping: it decodes (demangles) low-level names into user-level names so that they can be read.

       Every alphanumeric word (consisting of letters, digits, underscores, dollars, or periods) seen in the input is
       a potential mangled name.  If the name decodes into a C++ name, the C++ name replaces the low-level name in
       the output, otherwise the original word is output.  In this way you can pass an entire assembler source file,
       containing mangled names, through c++filt and see the same source file containing demangled names.

       You can also use c++filt to decipher individual symbols by passing them on the command line:

               c++filt <symbol>

       If no symbol arguments are given, c++filt reads symbol names from the standard input instead.  All the results
       are printed on the standard output.  The difference between reading names from the command line versus reading
       names from the standard input is that command line arguments are expected to be just mangled names and no
       checking is performed to separate them from surrounding text.  Thus for example:

               c++filt -n _Z1fv

       will work and demangle the name to "f()" whereas:

               c++filt -n _Z1fv,

       will not work.  (Note the extra comma at the end of the mangled name which makes it invalid).  This command
       however will work:

               echo _Z1fv, | c++filt -n

       and will display "f(),", i.e., the demangled name followed by a trailing comma.  This behaviour is because
       when the names are read from the standard input it is expected that they might be part of an assembler source
       file where there might be extra, extraneous characters trailing after a mangled name.  For example:

                   .type   _Z1fv, @function

OPTIONS
       -_
       --strip-underscore
           On some systems, both the C and C++ compilers put an underscore in front of every name.  For example, the
           C name "foo" gets the low-level name "_foo".  This option removes the initial underscore.  Whether c++filt
           removes the underscore by default is target dependent.
           normally only used internally in the compiler, and they can be confused with non-mangled names.  For
           example, a function called "a" treated as a mangled type name would be demangled to "signed char".

       -i
       --no-verbose
           Do not include implementation details (if any) in the demangled output.

       -s format
       --format=format
           c++filt can decode various methods of mangling, used by different compilers.  The argument to this option
           selects which method it uses:

           "auto"
               Automatic selection based on executable (the default method)

           "gnu"
               the one used by the GNU C++ compiler (g++)

           "lucid"
               the one used by the Lucid compiler (lcc)

           "arm"
               the one specified by the C++ Annotated Reference Manual

           "hp"
               the one used by the HP compiler (aCC)

           "edg"
               the one used by the EDG compiler

           "gnu-v3"
               the one used by the GNU C++ compiler (g++) with the V3 ABI.

           "java"
               the one used by the GNU Java compiler (gcj)

           "gnat"
               the one used by the GNU Ada compiler (GNAT).

       --help
           Print a summary of the options to c++filt and exit.

       --version
           Print the version number of c++filt and exit.

       @file
           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.


       included in the section entitled "GNU Free Documentation License".



binutils-2.25                                         2014-12-23                                           C++FILT(1)