LLVM-CXXMAP(1)                       LLVM                       LLVM-CXXMAP(1)

NAME
       llvm-cxxmap - Mangled name remapping tool

SYNOPSIS
       llvm-cxxmap [options] symbol-file-1 symbol-file-2

DESCRIPTION
       The llvm-cxxmap tool performs fuzzy matching of C++ mangled names,
       based on a file describing name components that should be considered
       equivalent.

       The symbol files should contain a list of C++ mangled names (one per
       line).  Blank lines and lines starting with # are ignored. The output
       is a list of pairs of equivalent symbols, one per line, of the form

          <symbol-1> <symbol-2>

       where <symbol-1> is a symbol from symbol-file-1 and <symbol-2> is a
       symbol from symbol-file-2. Mappings for which the two symbols are
       identical are omitted.

OPTIONS

       -remapping-file=file, -r=file
              Specify a file containing a list of equivalence rules that
              should be used to determine whether two symbols are equivalent.
              Required.  See REMAPPING FILE.

       -output=file, -o=file
              Specify a file to write the list of matched names to. If
              unspecified, the list will be written to stdout.

       -Wambiguous
              Produce a warning if there are multiple equivalent (but
              distinct) symbols in symbol-file-2.

       -Wincomplete
              Produce a warning if symbol-file-1 contains a symbol for which
              there is no equivalent symbol in symbol-file-2.

REMAPPING FILE
       The remapping file is a text file containing lines of the form

          fragmentkind fragment1 fragment2

       where fragmentkind is one of name, type, or encoding, indicating
       whether the following mangled name fragments are <name <http://itanium-
       cxx-abi.github.io/cxx-abi/abi.html#mangle.name>>s, <type <http://
       itanium-cxx-abi.github.io/cxx-abi/abi.html#mangle.type>>s, or <encoding
       <http://itanium-cxx-abi.github.io/cxx-abi/abi.html#mangle.encoding>>s,
       respectively.  Blank lines and lines starting with # are ignored.

       Unmangled C names can be expressed as an encoding that is a
       (length-prefixed) <source-name <http://itanium-cxx-abi.github.io/cxx-
       abi/abi.html#mangle.source-name>>:

          # C function "void foo_bar()" is remapped to C++ function "void foo::bar()".
          encoding 7foo_bar _Z3foo3barv

       For convenience, built-in <substitution>s such as St and Ss are
       accepted as <name>s (even though they technically are not <name>s).

       For example, to specify that absl::string_view and std::string_view
       should be treated as equivalent, the following remapping file could be
       used:

          # absl::string_view is considered equivalent to std::string_view
          type N4absl11string_viewE St17basic_string_viewIcSt11char_traitsIcEE

          # std:: might be std::__1:: in libc++ or std::__cxx11:: in libstdc++
          name St St3__1
          name St St7__cxx11

       Note:
          Symbol remapping is currently only supported for C++ mangled names
          following the Itanium C++ ABI mangling scheme. This covers all C++
          targets supported by Clang other than Windows targets.

Author
       Maintained by the LLVM Team (https://llvm.org/).

Copyright
       2003-2026, LLVM Project

22                                2026-07-15                    LLVM-CXXMAP(1)