sha256-hasher: Make it no-std compatible #384
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
#### Problem The sha256-hasher doesn't compile in real no-std environments. #### Summary of changes This was an easy fix, simply don't pull in default features for the sha2 crate. This means we disable OIDs for hashes, and the ability to finalize hashes into Box'ed values. Since we don't use that, it should be safe to disable. Also, the crate was a no-op to build without the sha2 feature, so I changed the no-std checking strategy to *exclude* features rather than include certain features, and moved it to `cargo hack` so that each crate and feature is tested individually.
febo
reviewed
Oct 16, 2025
| ./cargo nightly hack check \ | ||
| -Zbuild-std=core \ | ||
| "--target=$target" \ | ||
| --no-default-features \ |
Contributor
There was a problem hiding this comment.
Should we be building each individual feature with no defaults, so having the --no-default-features argument?
Collaborator
Author
There was a problem hiding this comment.
Yep, that's included with --each-feature on cargo hack:
+ exec cargo +nightly-2025-06-29 hack check -Zbuild-std=core --target=bpfel-unknown-none --exclude-features=atomic,bincode,default,dev-context-only-utils,frozen-abi,rand,std,verify,alloc,borsh,curve25519,serde --each-feature -p solana-address -p solana-clock -p solana-commitment-config -p solana-define-syscall -p solana-epoch-info -p solana-fee-calculator -p solana-hash -p solana-msg -p solana-program-error -p solana-program-log -p solana-program-log-macro -p solana-program-memory -p solana-rent -p solana-sanitize -p solana-sdk-ids -p solana-sha256-hasher -p solana-signature -p solana-sysvar-id -p solana-system-interface
info: running `cargo check -Zbuild-std=core --target bpfel-unknown-none --no-default-features` on solana-address (1/32)
...
Collaborator
Author
There was a problem hiding this comment.
And then it enables each feature one by one
Contributor
Do we need to test the build with just |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Problem
The sha256-hasher doesn't compile in real no-std environments.
Summary of changes
This was an easy fix, simply don't pull in default features for the sha2 crate. This means we disable OIDs for hashes, and the ability to finalize hashes into Box'ed values. Since we don't use that, it should be safe to disable.
Also, the crate was a no-op to build without the sha2 feature, so I changed the no-std checking strategy to exclude features rather than include certain features, and moved it to
cargo hackso that each crate and feature is tested individually.