Consider removing useless `-sign-ext` flag in substrate-wasm-builder #5777

StackOverflowExcept1on · 2024-09-19T18:12:18Z

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Motivation

https://github.com/rust-lang/blog.rust-lang.org/blob/4a72d620768932213baf39b03c6f1e61c00cd038/posts/2024-08-26-webassembly-targets-change-in-default-target-features.md

Request

Should be removed here

polkadot-sdk/substrate/utils/wasm-builder/src/wasm_project.rs

Lines 836 to 842 in c8d5e5a

    
           let mut rustflags = String::new(); 
        
           match target { 
        
           	RuntimeTarget::Wasm => { 
        
           		rustflags.push_str( 
        
           			"-C target-cpu=mvp -C target-feature=-sign-ext -C link-arg=--export-table ", 
        
           		); 
        
           	},

Solution

No response

Are you willing to help with this request?

Maybe (please elaborate above)

bkchr · 2024-09-19T20:09:21Z

Do you have a little bit more context?

StackOverflowExcept1on · 2024-09-19T20:12:46Z

@bkchr Rust 1.82 (stable Oct 17) enables multi-value and reference-types by default. I think it makes sense to additionally disable these features.

nazar-pc · 2024-09-20T18:50:56Z

According to link you have provided -C target-cpu=mvp is already sufficient to disable all of these features, not sure why Substrate also has -C target-feature=-sign-ext given that same document explicitly mentions that it'll be disabled for mvp CPU.

StackOverflowExcept1on · 2024-09-20T19:39:21Z

Yep, maybe it make sense just leave -C target-cpu=mvp since Rust added more documentation about this stuff

bkchr · 2024-09-22T06:13:11Z

not sure why Substrate also has -C target-feature=-sign-ext given that same document explicitly mentions that it'll be disabled for mvp CPU.

Apparently it did not worked before: paritytech/substrate#13804 (comment)

AFAIR we also just disabled this feature because there were issues with our wasm parser and not because we didn't wanted this feature.

CC @koute

StackOverflowExcept1on · 2024-12-14T13:46:36Z

@bkchr @koute We could switch to the new target wasm32v1-none (it will be stabilized starting with Rust 1.84 and no more hacks with RUSTC_BOOTSTRAP=1) instead of wasm32-unknown-unknown.

bkchr · 2024-12-14T15:02:14Z

Sounds reasonable

StackOverflowExcept1on · 2024-12-15T05:03:44Z

@bkchr @koute I could do PR that would change the target to wasm32v1-none, but it doesn't have std as wasm32-unknown-unknown. Also, I don't fully understand why every runtime has this line:

polkadot-sdk/templates/minimal/runtime/src/lib.rs

Line 20 in bd2c35f

#![cfg_attr(not(feature = "std"), no_std)]

I.e. does this mean that the runtime requires std? In which cases does it use std and in which cases does it not?

bkchr · 2024-12-16T08:52:33Z

I.e. does this mean that the runtime requires std? In which cases does it use std and in which cases does it not?

No, the piece of code you have linked means that if std feature is not set, no_std is set to announce to rustc that std is not required.

I could do PR that would change the target to wasm32v1-none, but it doesn't have std as wasm32-unknown-unknown.

This would need to be done in a backwards compatible way, aka only do so if the new target exists.

# Description Resolves #5777 Previously `wasm-builder` used hacks such as `-Zbuild-std` (required `rust-src` component) and `RUSTC_BOOTSTRAP=1` to build WASM runtime without WASM features: `sign-ext`, `multivalue` and `reference-types`, but since Rust 1.84 (will be stable on 9 January, 2025) the situation has improved as there is new [`wasm32v1-none`](https://doc.rust-lang.org/beta/rustc/platform-support/wasm32v1-none.html) target that disables all "post-MVP" WASM features except `mutable-globals`. Previously, your `rust-toolchain.toml` looked like this: ```toml [toolchain] channel = "stable" components = ["rust-src"] targets = ["wasm32-unknown-unknown"] profile = "default" ``` It should now be updated to something like this: ```toml [toolchain] channel = "stable" targets = ["wasm32v1-none"] profile = "default" ``` To build the runtime: ```bash cargo build --package minimal-template-runtime --release ``` ## Integration If you are using Rust 1.84 and above, then install the `wasm32v1-none` target instead of `wasm32-unknown-unknown` as shown above. You can also remove the unnecessary `rust-src` component. Also note the slight differences in conditional compilation: - `wasm32-unknown-unknown`: `#[cfg(all(target_family = "wasm", target_os = "unknown"))]` - `wasm32v1-none`: `#[cfg(all(target_family = "wasm", target_os = "none"))]` Avoid using `target_os = "unknown"` in `#[cfg(...)]` or `#[cfg_attr(...)]` and instead use `target_family = "wasm"` or `target_arch = "wasm32"` in the runtime code. ## Review Notes Wasm builder requires the following prerequisites for building the WASM binary: - Rust >= 1.68 and Rust < 1.84: - `wasm32-unknown-unknown` target - `rust-src` component - Rust >= 1.84: - `wasm32v1-none` target - no more `-Zbuild-std` and `RUSTC_BOOTSTRAP=1` hacks and `rust-src` component requirements! --------- Co-authored-by: Bastian Köcher <git@kchr.de> Co-authored-by: Bastian Köcher <info@kchr.de>

…ytech#7008) # Description Resolves paritytech#5777 Previously `wasm-builder` used hacks such as `-Zbuild-std` (required `rust-src` component) and `RUSTC_BOOTSTRAP=1` to build WASM runtime without WASM features: `sign-ext`, `multivalue` and `reference-types`, but since Rust 1.84 (will be stable on 9 January, 2025) the situation has improved as there is new [`wasm32v1-none`](https://doc.rust-lang.org/beta/rustc/platform-support/wasm32v1-none.html) target that disables all "post-MVP" WASM features except `mutable-globals`. Previously, your `rust-toolchain.toml` looked like this: ```toml [toolchain] channel = "stable" components = ["rust-src"] targets = ["wasm32-unknown-unknown"] profile = "default" ``` It should now be updated to something like this: ```toml [toolchain] channel = "stable" targets = ["wasm32v1-none"] profile = "default" ``` To build the runtime: ```bash cargo build --package minimal-template-runtime --release ``` ## Integration If you are using Rust 1.84 and above, then install the `wasm32v1-none` target instead of `wasm32-unknown-unknown` as shown above. You can also remove the unnecessary `rust-src` component. Also note the slight differences in conditional compilation: - `wasm32-unknown-unknown`: `#[cfg(all(target_family = "wasm", target_os = "unknown"))]` - `wasm32v1-none`: `#[cfg(all(target_family = "wasm", target_os = "none"))]` Avoid using `target_os = "unknown"` in `#[cfg(...)]` or `#[cfg_attr(...)]` and instead use `target_family = "wasm"` or `target_arch = "wasm32"` in the runtime code. ## Review Notes Wasm builder requires the following prerequisites for building the WASM binary: - Rust >= 1.68 and Rust < 1.84: - `wasm32-unknown-unknown` target - `rust-src` component - Rust >= 1.84: - `wasm32v1-none` target - no more `-Zbuild-std` and `RUSTC_BOOTSTRAP=1` hacks and `rust-src` component requirements! --------- Co-authored-by: Bastian Köcher <git@kchr.de> Co-authored-by: Bastian Köcher <info@kchr.de>

…ytech#7008) Resolves paritytech#5777 Previously `wasm-builder` used hacks such as `-Zbuild-std` (required `rust-src` component) and `RUSTC_BOOTSTRAP=1` to build WASM runtime without WASM features: `sign-ext`, `multivalue` and `reference-types`, but since Rust 1.84 (will be stable on 9 January, 2025) the situation has improved as there is new [`wasm32v1-none`](https://doc.rust-lang.org/beta/rustc/platform-support/wasm32v1-none.html) target that disables all "post-MVP" WASM features except `mutable-globals`. Previously, your `rust-toolchain.toml` looked like this: ```toml [toolchain] channel = "stable" components = ["rust-src"] targets = ["wasm32-unknown-unknown"] profile = "default" ``` It should now be updated to something like this: ```toml [toolchain] channel = "stable" targets = ["wasm32v1-none"] profile = "default" ``` To build the runtime: ```bash cargo build --package minimal-template-runtime --release ``` If you are using Rust 1.84 and above, then install the `wasm32v1-none` target instead of `wasm32-unknown-unknown` as shown above. You can also remove the unnecessary `rust-src` component. Also note the slight differences in conditional compilation: - `wasm32-unknown-unknown`: `#[cfg(all(target_family = "wasm", target_os = "unknown"))]` - `wasm32v1-none`: `#[cfg(all(target_family = "wasm", target_os = "none"))]` Avoid using `target_os = "unknown"` in `#[cfg(...)]` or `#[cfg_attr(...)]` and instead use `target_family = "wasm"` or `target_arch = "wasm32"` in the runtime code. Wasm builder requires the following prerequisites for building the WASM binary: - Rust >= 1.68 and Rust < 1.84: - `wasm32-unknown-unknown` target - `rust-src` component - Rust >= 1.84: - `wasm32v1-none` target - no more `-Zbuild-std` and `RUSTC_BOOTSTRAP=1` hacks and `rust-src` component requirements! --------- Co-authored-by: Bastian Köcher <git@kchr.de> Co-authored-by: Bastian Köcher <info@kchr.de>

StackOverflowExcept1on added the I5-enhancement An additional feature request. label Sep 19, 2024

github-actions bot added the I10-unconfirmed Issue might be valid, but it's not yet known. label Sep 19, 2024

StackOverflowExcept1on changed the title ~~Consider to disable multi-value and reference-types features~~ Consider disabling multi-value and reference-types features Sep 19, 2024

StackOverflowExcept1on changed the title ~~Consider disabling multi-value and reference-types features~~ Consider removing useless -sign-ext flag in substrate-wasm-builder Sep 20, 2024

StackOverflowExcept1on mentioned this issue Dec 27, 2024

feat(wasm-builder): add support for new wasm32v1-none target #7008

Merged

bkchr closed this as completed in #7008 Feb 9, 2025

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Consider removing useless `-sign-ext` flag in substrate-wasm-builder #5777

Consider removing useless `-sign-ext` flag in substrate-wasm-builder #5777

StackOverflowExcept1on commented Sep 19, 2024 •

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bkchr commented Sep 19, 2024

StackOverflowExcept1on commented Sep 19, 2024

nazar-pc commented Sep 20, 2024

StackOverflowExcept1on commented Sep 20, 2024 •

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bkchr commented Sep 22, 2024 •

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StackOverflowExcept1on commented Dec 14, 2024 •

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bkchr commented Dec 14, 2024

StackOverflowExcept1on commented Dec 15, 2024

bkchr commented Dec 16, 2024

Consider removing useless -sign-ext flag in substrate-wasm-builder #5777

Consider removing useless -sign-ext flag in substrate-wasm-builder #5777

Comments

StackOverflowExcept1on commented Sep 19, 2024 • edited Loading

Is there an existing issue?

Experiencing problems? Have you tried our Stack Exchange first?

Motivation

Request

Solution

Are you willing to help with this request?

bkchr commented Sep 19, 2024

StackOverflowExcept1on commented Sep 19, 2024

nazar-pc commented Sep 20, 2024

StackOverflowExcept1on commented Sep 20, 2024 • edited Loading

bkchr commented Sep 22, 2024 • edited Loading

StackOverflowExcept1on commented Dec 14, 2024 • edited Loading

bkchr commented Dec 14, 2024

StackOverflowExcept1on commented Dec 15, 2024

bkchr commented Dec 16, 2024

Consider removing useless `-sign-ext` flag in substrate-wasm-builder #5777

Consider removing useless `-sign-ext` flag in substrate-wasm-builder #5777

StackOverflowExcept1on commented Sep 19, 2024 •

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StackOverflowExcept1on commented Sep 20, 2024 •

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bkchr commented Sep 22, 2024 •

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StackOverflowExcept1on commented Dec 14, 2024 •

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