LLVM-CXXFILT(1)

💅 LLVM-CXXFILT(1) — the LLVM manual, bestie edition

okay so, welcome to llvm-cxxfilt, part of the LLVM fam 🫶. Sit down, grab a boba, we're gonna talk about demangling. Yes it's as iconic as it sounds.

---

✨ NAME ✨

llvm-cxxfilt — the LLVM symbol name demangler 🌸

✨ SYNOPSIS ✨

llvm-cxxfilt [options] [mangled names...]

💖 DESCRIPTION 💖

llvm-cxxfilt is a symbol demangler, and honestly? It's giving "drop-in replacement for the GNU c++filt tool" 👑. You hand it a bunch of symbol names, and it prints their demangled form on the standard output stream. That's it. That's the whole job. Slay.

And if a name can't be demangled? No drama, no error, it just gets printed as-is. We don't gatekeep, we don't crash 💅.

Now, if you don't drop any names on the command line, it'll read them interactively from the standard input stream instead ✨. But here's the cute little detail you need to know: when it's reading from standard input, it splits each line on characters that aren't part of valid Itanium name manglings — aka characters that are not alphanumeric, '.', '$', or '_'. And the separators between names? They get copied to the output as-is. Zero crumbs left behind 🎀.

🦋 EXAMPLE 🦋

$ llvm-cxxfilt _Z3foov _Z3bari not_mangled
foo()
bar(int)
not_mangled
$ cat input.txt
| _Z3foov *** _Z3bari *** not_mangled |
$ llvm-cxxfilt < input.txt
| foo() *** bar(int) *** not_mangled |

look at that. not_mangled said "I'm staying exactly as I am" and honestly? respect 💀

🔥 OPTIONS 🔥

• --format=<value>, -s — which mangling scheme to assume. Valid values are auto (the default — it auto-detects the style for you, main character energy) and gnu (assume the GNU/Itanium style).
• --help, -h — print a summary of the command line options. Your safety net 🫶
• --no-params, -p — do NOT demangle function parameters or return types. Keep it mysterious.
• --no-strip-underscore, -n — do not strip a leading underscore. This is the default for all platforms except Mach-O based hosts. Periodt.
• --strip-underscore, -_ — strip a single leading underscore, if present, from each input name before demangling. On by default on Mach-O based platforms 😌
• --types, -t — attempt to demangle names as type names as well as function names. Versatile queen ✨
• --version — display the version of the llvm-cxxfilt executable.
• @<FILE> — read command-line options from response file <FILE>. iykyk 📁

💀 EXIT STATUS 💀

llvm-cxxfilt returns 0 unless it encounters a usage error — in which case, bestie, a non-zero exit code is returned. 🙈

🌈 SEE ALSO 🌈

• llvm-nm(1) <llvm-nm.html> — go say hi 👋

🎀 Author 🎀

Maintained by the LLVM Team (https://llvm.org/). They're literally the blueprint 💜

🍓 Copyright 🍓

2003-2026, LLVM Project

---

and that's the whole page, bestie — no cap, every flag, every default, every separator character 💖

this gorgeous little manpage is version 15, dated 2026-09-09, and it goes out to you from the LLVM project with love 🧚✨ mwah, now go demangle something 💅