C++FILT(1) GNU Development Tools C++FILT(1)
NAME
c++filt - Demangle C++ and Java symbols.
SYNOPSIS
c++filt [-_|--strip-underscores]
[-n|--no-strip-underscores]
[-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-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.
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