DEMANGLE(1) User Commands DEMANGLE(1)

NAME

demangle - demangle symbols

SYNOPSIS

demangle [-l lang] [symbol...]

DESCRIPTION

The demangle utility attempts to detect mangled symbols and transform
them back into a more human friendly version of the symbol.

Some languages allow the same identifier to refer to multiple things
(functions, variables, etc.) where some additional context such as
parameter types, return types, etc. are used to disambiguate between
the symbols sharing the same name. When compiling such languages into
an executable form, most binary formats do not allow for duplicate
symbol names or provide a way to disambiguate between duplicate names.

To solve this problem, many languages will use the additional context
from the source code to transform the symbol name into a unique name.
This process is called name mangling. While the resulting name is
predictable, the mangled names are often difficult for humans to
interpret.

The demangle utility can be invoked in one of two ways. In the first
method, symbol is demangled and the result is written to standard out,
one line per input symbol. If any input symbol cannot be demangled,
the original value of symbol is output unchanged. In the second
method, demangle reads standard in, and whenever it encounters a
potential symbol, it will attempt to replace the symbol in standard out
with the demangled version. If the symbol cannot be demangled, it is
output unchanged.

For either method, if an error other than attempting to demangle an
non-mangled symbol (e.g. out of memory), that error will be written to
standard error.

OPTIONS

-l lang Treat all potential symbols as symbols from lang. By
default, demangle will attempt to detect the language and
demangle symbols for all supported languages. Current
supported values of lang are:

c++ The C++ mangling format defined by the Itanium
ABI. While the mangling format was originally
defined for the Itanium processor, g++ and
clang use this format for all their supported
platforms (including x86 and SPARC).

rust The rust v0 (Rust RFC 2603) and legacy mangling
formats. The specific rust mangling format
will be automatically detected.

auto Attempt to detect the language automatically
(default).

EXIT STATUS

The demangle utility exits 0 on success, and >0 if an error occurs.

EXAMPLES

Example 1 Demangle symbols given as command line arguments.

% demangle '_ZGVN9__gnu_cxx16bitmap_allocatorIwE13_S_mem_blocksE'
guard variable for __gnu_cxx::bitmap_allocator<wchar_t>::_S_mem_blocks
%

Example 2 Demangle symbols from the output of another command.

% grep slice rust.c | head -1
T("__ZN4core5slice89_$LT$impl$u20$core..iter..traits..IntoIterator$u20$for$u20$$RF$$u27$a$u20$$u5b$T$u5d$$GT$9into_iter17h450e234d27262170E",
% grep slice rust.c | head -1 | demangle
T("core::slice::<impl core::iter::traits::IntoIterator for &'a [T]>::into_iter::h450e234d27262170",
%

INTERFACE STABILITY

The command line options are Uncommitted. The output format is
Not-an-Interface.

illumos May 12, 2024 illumos