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

6       c++filt - Demangle C++ and Java symbols.
7

SYNOPSIS

9       c++filt [-_|--strip-underscores]
10               [-n|--no-strip-underscores]
11               [-p|--no-params]
12               [-t|--types]
13               [-i|--no-verbose]
14               [-s format|--format=format]
15               [--help]  [--version]  [symbol...]
16

DESCRIPTION

18       The C++ and Java languages provide function overloading, which means
19       that you can write many functions with the same name, providing that
20       each function takes parameters of different types.  In order to be able
21       to distinguish these similarly named functions C++ and Java encode them
22       into a low-level assembler name which uniquely identifies each
23       different version.  This process is known as mangling. The c++filt [1]
24       program does the inverse mapping: it decodes (demangles) low-level
25       names into user-level names so that they can be read.
26
27       Every alphanumeric word (consisting of letters, digits, underscores,
28       dollars, or periods) seen in the input is a potential mangled name.  If
29       the name decodes into a C++ name, the C++ name replaces the low-level
30       name in the output, otherwise the original word is output.  In this way
31       you can pass an entire assembler source file, containing mangled names,
32       through c++filt and see the same source file containing demangled
33       names.
34
35       You can also use c++filt to decipher individual symbols by passing them
36       on the command line:
37
38               c++filt <symbol>
39
40       If no symbol arguments are given, c++filt reads symbol names from the
41       standard input instead.  All the results are printed on the standard
42       output.  The difference between reading names from the command line
43       versus reading names from the standard input is that command line
44       arguments are expected to be just mangled names and no checking is
45       performed to separate them from surrounding text.  Thus for example:
46
47               c++filt -n _Z1fv
48
49       will work and demangle the name to "f()" whereas:
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51               c++filt -n _Z1fv,
52
53       will not work.  (Note the extra comma at the end of the mangled name
54       which makes it invalid).  This command however will work:
55
56               echo _Z1fv, | c++filt -n
57
58       and will display "f(),", i.e., the demangled name followed by a
59       trailing comma.  This behaviour is because when the names are read from
60       the standard input it is expected that they might be part of an
61       assembler source file where there might be extra, extraneous characters
62       trailing after a mangled name.  For example:
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64                   .type   _Z1fv, @function
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OPTIONS

67       -_
68       --strip-underscores
69           On some systems, both the C and C++ compilers put an underscore in
70           front of every name.  For example, the C name "foo" gets the low-
71           level name "_foo".  This option removes the initial underscore.
72           Whether c++filt removes the underscore by default is target
73           dependent.
74
75       -j
76       --java
77           Prints demangled names using Java syntax.  The default is to use
78           C++ syntax.
79
80       -n
81       --no-strip-underscores
82           Do not remove the initial underscore.
83
84       -p
85       --no-params
86           When demangling the name of a function, do not display the types of
87           the function's parameters.
88
89       -t
90       --types
91           Attempt to demangle types as well as function names.  This is
92           disabled by default since mangled types are normally only used
93           internally in the compiler, and they can be confused with non-
94           mangled names.  For example, a function called "a" treated as a
95           mangled type name would be demangled to "signed char".
96
97       -i
98       --no-verbose
99           Do not include implementation details (if any) in the demangled
100           output.
101
102       -s format
103       --format=format
104           c++filt can decode various methods of mangling, used by different
105           compilers.  The argument to this option selects which method it
106           uses:
107
108           "auto"
109               Automatic selection based on executable (the default method)
110
111           "gnu"
112               the one used by the GNU C++ compiler (g++)
113
114           "lucid"
115               the one used by the Lucid compiler (lcc)
116
117           "arm"
118               the one specified by the C++ Annotated Reference Manual
119
120           "hp"
121               the one used by the HP compiler (aCC)
122
123           "edg"
124               the one used by the EDG compiler
125
126           "gnu-v3"
127               the one used by the GNU C++ compiler (g++) with the V3 ABI.
128
129           "java"
130               the one used by the GNU Java compiler (gcj)
131
132           "gnat"
133               the one used by the GNU Ada compiler (GNAT).
134
135       --help
136           Print a summary of the options to c++filt and exit.
137
138       --version
139           Print the version number of c++filt and exit.
140
141       @file
142           Read command-line options from file.  The options read are inserted
143           in place of the original @file option.  If file does not exist, or
144           cannot be read, then the option will be treated literally, and not
145           removed.
146
147           Options in file are separated by whitespace.  A whitespace
148           character may be included in an option by surrounding the entire
149           option in either single or double quotes.  Any character (including
150           a backslash) may be included by prefixing the character to be
151           included with a backslash.  The file may itself contain additional
152           @file options; any such options will be processed recursively.
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FOOTNOTES

155       1.  MS-DOS does not allow "+" characters in file names, so on MS-DOS
156           this program is named CXXFILT.
157

SEE ALSO

159       the Info entries for binutils.
160
162       Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
163       2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software
164       Foundation, Inc.
165
166       Permission is granted to copy, distribute and/or modify this document
167       under the terms of the GNU Free Documentation License, Version 1.2 or
168       any later version published by the Free Software Foundation; with no
169       Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
170       Texts.  A copy of the license is included in the section entitled "GNU
171       Free Documentation License".
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175binutils-2.19.50.0.1              2009-07-28                        C++FILT(1)
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