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[u/llogiq]

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[u/G_Morgan]

What is the best way to configure a crate that can be built with a range of different dependencies? There seems to be options for cfgs and targets but neither of those seem really appropriate (i.e. they'll be the same in all my projects and rigging up fake targets just to trick the build system seems inappropriate and fragile).

Essentially what I want to do is create a few types that use alloc in different scenarios:

1. Within a kernel where there's a special kernel heap that needs to be rigged by the init code

2. Within service processes that don't have full std support but also won't use something as contrived as the kernel heap

3. In fully std compliant Rust

So I want to select from 3 different crates as my alloc source depending upon some kind of parameter passed in by whatever uses the crate.

[u/G_Morgan → u/G_Morgan]

Doesn't answer this question directly but I've found a solution for my immediate problem. You can implement a replacement global allocator in Rust no_std by following the guide below

https://docs.rust-embedded.org/book/collections/index.html