Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Tune platform-specific crate dependencies #724

Merged
merged 4 commits into from Feb 6, 2019
Merged

Tune platform-specific crate dependencies #724

Changes from 1 commit
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
af8a86d
rand_jitter: don't use std feature of libc
dhardy Feb 4, 2019
6357a4c
rand: remove unused winapi dependency
dhardy Feb 4, 2019
1ae5988
rand: support reseeding without libstd
dhardy Feb 4, 2019
4ca5ee3
rand_jitter: bump version number to 0.1.3
dhardy Feb 4, 2019
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
4 changes: 3 additions & 1 deletion rand_jitter/Cargo.toml
View file
Open in desktop
Expand Up @@ -18,7 +18,9 @@ rand_core = { path = "../rand_core", version = "0.4" }
log = { version = "0.4", optional = true }

[target.'cfg(any(target_os = "macos", target_os = "ios"))'.dependencies]
libc = "0.2"
# We don't need the 'use_std' feature and depending on it causes
# issues due to: https://github.com/rust-lang/cargo/issues/1197
Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I think this statement is slightly misleading, the problem is that we use the use_std feature even for no_std builds. Would it be better if we tie libc's use_std feature to our std feature? I'm not sure how cargo works, but I imagine it might avoid recompiling the libc crate, when it is already required elsewhere with the use_std feature.

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

No, I believe features are unified before the build takes place, so if another crate depends on libc with use_std it will just get built once with the feature enabled. We don't actually need use_std so there's no reason to depend on it.

The problem pointed out in #723 is that rand_jitter depending on libc with default features for a different target causes libc to be built with default features when depended on without by other crates in the build — obviously unintended functionality.

Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I see, then we should not use use_std in any case.

libc = { version = "0.2", default_features = false }

[target.'cfg(target_os = "windows")'.dependencies]
winapi = { version = "0.3", features = ["profileapi"] }
Expand Down