Fix the import path for size_of and align_of

[r-chiba]

Description

This change fixes to import size_of and align_of from the core crate.

We have seen an error failing to resolve this import directive.

Sources

Checklist

• Relevant tests in libc-test/semver have been updated
• No placeholder or unstable values like *LAST or *MAX are
  included (see #3131)
• Tested locally (cd libc-test && cargo test --target mytarget);
  especially relevant for platforms that may not be checked in CI

@rustbot label +stable-nominated

[tgross35]

What is the error you are seeing? We import core::mem so I'm not sure why things wouldn't be working. I'd expect fmt::Debug to be in the same boat.

[r-chiba]

We saw this error on a Windows environment:

00:47:54 error[E0432]: unresolved import `mem`
00:47:54 --> external/+_repo_rules2+libc/src\macros.rs:81:28
00:47:54 |
00:47:54 81 |             pub(crate) use mem::{align_of, align_of_val, size_of, size_of_val};
00:47:54 |                            ^^^ help: a similar path exists: `self::mem`
00:47:54 |
00:47:54 ::: external/+_repo_rules2+libc/src/lib.rs:57:9
00:47:54 |
00:47:54 57 |         prelude!();
00:47:54 |         ---------- in this macro invocation
00:47:54 |
00:47:54 = note: this error originates in the macro `prelude` (in Nightly builds, run with -Z macro-backtrace for more info)
00:47:54 
00:47:54 error: aborting due to 1 previous error

[tgross35]

Do you have the rustc invocation that caused that and some more toolchain info? I'm not able to reproduce, of course, and I don't really understand where the error would be coming from. Libc isn't getting built with an old edition or something, is it?

[r-chiba]

I think the rustc version is 1.88.0 but I couldn't find the exact command used for the build.

The context is that the error happened to one of the components of (the internal version of) Android's AOSP project when I updated the libc crate version used for Android build (internal version of https://cs.android.com/android/platform/superproject/main/+/main:external/rust/android-crates-io/) from 0.2.172 to 0.2.175.

I'm so sorry but I'm not a developer of the component failed to build and I have no idea how the component is built. And unfortunately I don't have a minimal reproducible case of the failure.