Python bindings for the LLVM Demangle library, with vendored LLVM source.

Exposes Itanium, Microsoft, Rust, and D language demanglers, plus ItaniumPartialDemangler for querying individual symbol components. Ships all LLVM versions 11–21 in a single package with runtime version selection. No system LLVM installation required.

pip install llvm-demangle-fxti

import llvmdemangle

llvmdemangle.demangle("_Z3fooi")           # 'foo(int)'
llvmdemangle.demangle("?foo@@YAHH@Z")      # 'int __cdecl foo(int)'

By default, the highest available LLVM version (21) is used. Use backend() to get a specific version:

import llvmdemangle

# Default (LLVM 21)
llvmdemangle.demangle("_Z3fooi")

# Use a specific LLVM version
v18 = llvmdemangle.backend(18)
v18.demangle("_Z3fooi")
v18.ItaniumPartialDemangler("_ZN3Foo3barEid")
v18.LLVM_VERSION  # 18

# See what's available
llvmdemangle.SUPPORTED_VERSIONS  # [11, 12, 13, ..., 21]

Integer constant indicating the LLVM version of the default backend (e.g. 21).

List of all available LLVM backend versions (e.g. [11, 12, ..., 21]).

Return the backend module for a specific LLVM version. The returned module has the same API as the top-level llvmdemangle module.

Auto-detect mangling scheme and demangle. Returns the original string if unrecognized.

llvmdemangle.demangle("_Z3fooi")       # 'foo(int)'
llvmdemangle.demangle("?foo@@YAHH@Z")  # 'int __cdecl foo(int)'
llvmdemangle.demangle("plain")         # 'plain'

Demangle an Itanium C++ ABI symbol. Returns None on failure.

parse_params=False omits function parameters (LLVM >= 18; ignored on older versions).

llvmdemangle.itanium_demangle("_Z3fooi")                        # 'foo(int)'
llvmdemangle.itanium_demangle("_Z3fooi", parse_params=False)    # 'foo'  (LLVM 18+)

Demangle a Microsoft Visual C++ symbol. Returns (demangled_name, n_read) or None.

llvmdemangle.microsoft_demangle("?foo@@YAHH@Z")
# ('int __cdecl foo(int)', 12)

llvmdemangle.microsoft_demangle("?foo@@YAHH@Z", flags=llvmdemangle.MSDF_NO_CALLING_CONVENTION)
# ('int foo(int)', 12)

Flag constants:

Demangle a Rust v0 symbol. Returns None on failure. Requires LLVM >= 13.

llvmdemangle.rust_demangle("_RNvC8my_crate3foo")  # 'my_crate::foo'

Demangle a D language symbol. Returns None on failure. Requires LLVM >= 14.

llvmdemangle.dlang_demangle("_Dmain")  # 'D main'

Demangle a non-Microsoft symbol (Itanium, Rust, or D). Returns None on failure. Requires LLVM >= 14. parse_params requires LLVM >= 18.

Get the Arm64EC insertion point in a mangled name. Requires LLVM >= 19.

Parse Itanium C++ symbols into an AST and query individual components. Raises ValueError if the name cannot be parsed.

d = llvmdemangle.ItaniumPartialDemangler("_ZN3Foo3barIiEEvi")
d.full_name              # 'void Foo::bar<int>(int)'
d.function_base_name     # 'bar'
d.function_decl_context  # 'Foo'
d.function_name          # 'Foo::bar<int>'
d.function_parameters    # '(int)'
d.function_return_type   # 'void'
d.is_function            # True
d.is_data                # False
d.is_ctor_or_dtor        # False
d.is_special_name        # False
d.has_function_qualifiers  # False

String properties return None when the property doesn't apply (e.g. function_name on a data symbol).

Functions unavailable for the selected LLVM backend raise NotImplementedError.

# 1. Vendor LLVM Demangle source (downloads from GitHub releases)
python vendor_llvm.py --llvm-version 18
python vendor_llvm.py --llvm-version 21

# 2. Build & install (compiles backends for all vendored versions)
pip install .

Supported LLVM versions: 11–21. Only vendored versions are compiled.

• Wrapper code: 0BSD
• LLVM Demangle source: Apache 2.0 with LLVM Exception