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c++filt

c++filt [ -_ | --strip-underscores ]
[ -n | --no-strip-underscores ]
[ -sformat | --format=format ]
[ --help ] [ --version ] [ symbol...]

The C++ language provides function overloading, which means that you can write many functions with the same name (providing each takes parameters of different types). All C++ function names are encoded into a low-level assembly label (this process is known as mangling). The c++filt program does the inverse mapping: it decodes (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 c++filt to decipher individual symbols:

c++filt symbol

If no symbol arguments are given, 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.

-_
--strip-underscores
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.

-n
--no-strip-underscores
Do not remove the initial underscore.

-s format
--format=format
GNU nm can decode three different methods of mangling, used by different C++ compilers. The argument to this option selects which method it uses:

gnu
The one used by the GNU compiler (the default method).

lucid
The one used by the Lucid compiler.

arm
The one specified by the C++ Annotated Reference Manual.

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

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

Warning:
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 future to decode a name passed as an argument on the command line; for example, c++filt symbol may in a future release become c++filt option symbol.