Rollup merge of #119590 - ChrisDenton:cfg-target-abi, r=Nilstrieb

Stabilize `cfg_target_abi`

This stabilizes the `cfg` option called `target_abi`:

```rust
#[cfg(target_abi = "eabihf")]
```

Tracking issue: #80970

fixes #78791
resolves #80970

compiler/rustc_feature/src/accepted.rs

@@ -84,6 +84,8 @@ declare_features! (
     (accepted, cfg_doctest, "1.40.0", Some(62210)),
     /// Enables `#[cfg(panic = "...")]` config key.
     (accepted, cfg_panic, "1.60.0", Some(77443)),
+    /// Allows `cfg(target_abi = "...")`.
+    (accepted, cfg_target_abi, "CURRENT_RUSTC_VERSION", Some(80970)),
     /// Allows `cfg(target_feature = "...")`.
     (accepted, cfg_target_feature, "1.27.0", Some(29717)),
     /// Allows `cfg(target_vendor = "...")`.

compiler/rustc_feature/src/builtin_attrs.rs

@@ -25,7 +25,6 @@ pub type GatedCfg = (Symbol, Symbol, GateFn);
 const GATED_CFGS: &[GatedCfg] = &[
     // (name in cfg, feature, function to check if the feature is enabled)
     (sym::overflow_checks, sym::cfg_overflow_checks, cfg_fn!(cfg_overflow_checks)),
-    (sym::target_abi, sym::cfg_target_abi, cfg_fn!(cfg_target_abi)),
     (sym::target_thread_local, sym::cfg_target_thread_local, cfg_fn!(cfg_target_thread_local)),
     (
         sym::target_has_atomic_equal_alignment,

compiler/rustc_feature/src/unstable.rs

@@ -373,8 +373,6 @@ declare_features! (
     (unstable, cfg_sanitize, "1.41.0", Some(39699)),
     /// Allows `cfg(sanitizer_cfi_generalize_pointers)` and `cfg(sanitizer_cfi_normalize_integers)`.
     (unstable, cfg_sanitizer_cfi, "1.77.0", Some(89653)),
-    /// Allows `cfg(target_abi = "...")`.
-    (unstable, cfg_target_abi, "1.55.0", Some(80970)),
     /// Allows `cfg(target(abi = "..."))`.
     (unstable, cfg_target_compact, "1.63.0", Some(96901)),
     /// Allows `cfg(target_has_atomic_load_store = "...")`.