# Objective
Let `bevy_utils` build with no default features.
`cargo build -p bevy_utils --no-default-features` currently fails with
```
error[E0433]: failed to resolve: use of unresolved module or unlinked crate `alloc`
--> crates\bevy_utils\src\debug_info.rs:1:5
|
1 | use alloc::{borrow::Cow, fmt, string::String};
| ^^^^^ use of unresolved module or unlinked crate `alloc`
|
= help: add `extern crate alloc` to use the `alloc` crate
error[E0432]: unresolved import `alloc`
--> crates\bevy_utils\src\debug_info.rs:1:5
|
1 | use alloc::{borrow::Cow, fmt, string::String};
| ^^^^^ help: a similar path exists: `core::alloc`
```
I would have expected CI to catch this earlier, but I have not
investigated why it did not.
## Solution
Wrap the parts of `DebugName` that use `Cow` and `String` in
`cfg::alloc!`.
If the `debug` feature is enabled, then `DebugName` itself stores a
`Cow`, so make the `debug` feature require `bevy_platform/alloc`.
That is, you can use `DebugName` in no-std contexts when it's just a
ZST! (I bet it's even possible to support no-std `debug` by storing
`&'static str` instead of `Cow<'static, str>`, but that seemed like too
much complexity for now.)
85448b767e
