WASM-TOOLS(1)

✨ WASM-TOOLS(1) ✨ — the user commands era 💅

okay bestie, we're diving into wasm-tools demangle, a lil' star in the wasm-tools family (that's the manual name, putting it right here up top so you're not lost 🫶). buckle up, this one's short but iconic.

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🎀 NAME 🎀

wasm-tools demangle — demangle Rust and C++ symbol names in the name section. yes, the whole job is un-mangling, and she does it flawlessly. ✨

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🌸 SYNOPSIS 🌸

wasm-tools demangle [OPTIONS] [INPUT]

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💖 DESCRIPTION 💖

okay so. this command detects a name section inside a wasm executable and then demangles any Rust and C++ symbol names it finds in there. that's it. that's the whole vibe. 😌

here's the part that actually matters tho: when tooling debugs a wasm module that uses the name section but doesn't run a demangler, it's gonna use the demangled names — because this command replaces the name section. so it's not just reading, it's rewriting. main character energy tbh 👑

🦋 Arguments: 🦋

• [INPUT] — the input file you wanna process, bestie.

if you don't provide it, or if it's -, then stdin gets read entirely and processed. and ngl, for most subcommands this input can be either a binary *.wasm file or a textual format *.wat file. both are welcome here, we don't gatekeep 💜

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✨ OPTIONS ✨

• --generate-dwarf <lines|full> — optionally generate DWARF debugging information from WebAssembly text files. 👀

so when the input to this command is a WebAssembly text file like *.wat, this option tells the text parser to insert DWARF debugging info that maps binary locations back to the original source locations in the input *.wat file. cute, right? but heads up: this has no effect if the INPUT argument is already a WebAssembly binary, or if the text format uses (module binary ...). it just vibes and does nothing in those cases. 🙈

• -g — shorthand for --generate-dwarf full. one letter, same slay 🫶
• -o, --output <OUTPUT> — where to place output. if you don't give one, stdout is used. simple as that 💅
• -v, --verbose... — use verbose output (-v info, -vv debug, -vvv trace). the more v's, the more you see. escalation nation 🔥
• --color <COLOR> — configuration over whether terminal colors are used in output. 🎨

supports one of auto|never|always|always-ansi. the default is to detect what to do based on the terminal environment, for example by using isatty. you know, the whole "is this even a real terminal" check.

[default: auto]

• -t, --wat — output the text format of WebAssembly instead of the binary format. hex girl moment ✨
• -h, --help — print help (see a summary with -h). the help for the help, we love a recursive icon 💀

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lowkey a warning but also just a fact: if you're feeding this a wasm binary and expecting --generate-dwarf to do something, it won't. and (module binary ...) text? also nope. don't come for me, come for the spec 🫶

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and that's the whole page, bestie!! you ate. 💖🌸🎀

this was wasm-tools demangle version 1.239.0+ds, dated August 2026 — shouting out the source and the date because they deserve their flowers too, periodt. 👑🦋✨