Skip to content
Permalink

Comparing changes

Choose two branches to see what’s changed or to start a new pull request. If you need to, you can also or learn more about diff comparisons.

Open a pull request

Create a new pull request by comparing changes across two branches. If you need to, you can also . Learn more about diff comparisons here.
base repository: rust-lang/compiler-builtins
Failed to load repositories. Confirm that selected base ref is valid, then try again.
Loading
base: master@{1day}
Choose a base ref
...
head repository: rust-lang/compiler-builtins
Failed to load repositories. Confirm that selected head ref is valid, then try again.
Loading
compare: master
Choose a head ref
  • 1 commit
  • 2 files changed
  • 1 contributor

Commits on Aug 5, 2025

  1. configure: Use CARGO_CFG_*_{F16,F128} rather than invoking rustc 

    Currently we run the `rustc` from the `RUSTC` environment variable to
figure out whether or not to enable `f16` and `f128`, based on the
`target_has_reliable_{f16,f128}` config. However, this does not know
about the codegen backend used, and the backend isn't trivial to check
in a build script (usually it gets set via `RUSTFLAGS`).

It turns out we don't actually need to run `rustc` here: Cargo
unconditionally emits all config from the relevant compiler as
`CARGO_CFG_*` variables, regardless of whether or not they are known
options. Switch to checking these for setting config rather than
invoking `rustc`.

As an added advantage, this will work with target.json files without any
special handling.

Fixes: ed17b95 ("Use the compiler to determine whether or not to enable `f16` and `f128`")
    @tgross35
    tgross35 committed Aug 5, 2025
    Configuration menu
    Copy the full SHA
    87a66ec View commit details
    Browse the repository at this point in the history
Loading