WebAssembly Core Specification

Version 2.0

W3C First Public Working Draft

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Andreas Rossberg (Dfinity Stiftung)
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This document describes version 2.0 of the core WebAssembly standard, a safe, portable, low-level code format designed for efficient execution and compact representation. WebAseembly Core is part of a collection of WebAssembly specifications: the Core WebAssembly Specification, the WebAssembly JS Interface, and the WebAssembly Web API.

Status of This Document

This section describes the status of this document at the time of its publication. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at https://www.w3.org/TR/.

Technical comments are welcomed by the Working Group to improve future versions of WebAssembly. GitHub Issues are preferred for discussion of this specification. When filing an issue, please put the text “wasm-core” in the title, preferably like this: “[wasm-core] …summary of comment…”. All issues and comments are archived.

This document was published by the WebAssembly Working Group as a First Public Working Draft using the Recommendation track.

Publication as a First Public Working Draft does not imply endorsement by W3C and its Members.

This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

This document was produced by a group operating under the 1 August 2017 W3C Patent Policy. W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.

This document is governed by the 2 November 2021 W3C Process Document.

1. Conformance

As well as sections marked as non-normative, all authoring guidelines, diagrams, examples, and notes in this specification are non-normative. Everything else in this specification is normative.

2. Security Considerations

See section 1.1.3 Security Considerations

3. Privacy Considerations

See section 1.1.3 Security Considerations