diff --git a/crates/core_simd/src/lib.rs b/crates/core_simd/src/lib.rs
index 9180e5c7dfd..dfb36d8c513 100644
--- a/crates/core_simd/src/lib.rs
+++ b/crates/core_simd/src/lib.rs
@@ -12,10 +12,27 @@
     repr_simd,
     simd_ffi,
     staged_api,
-    stdsimd,
     strict_provenance,
     ptr_metadata
 )]
+#![cfg_attr(
+    all(
+        any(target_arch = "aarch64", target_arch = "arm",),
+        any(
+            all(target_feature = "v6", not(target_feature = "mclass")),
+            all(target_feature = "mclass", target_feature = "dsp"),
+        )
+    ),
+    feature(stdarch_arm_dsp)
+)]
+#![cfg_attr(
+    all(target_arch = "arm", target_feature = "v7"),
+    feature(stdarch_arm_neon_intrinsics)
+)]
+#![cfg_attr(
+    any(target_arch = "powerpc", target_arch = "powerpc64"),
+    feature(stdarch_powerpc)
+)]
 #![warn(missing_docs, clippy::missing_inline_in_public_items)] // basically all items, really
 #![deny(unsafe_op_in_unsafe_fn, clippy::undocumented_unsafe_blocks)]
 #![allow(internal_features)]
diff --git a/crates/test_helpers/src/lib.rs b/crates/test_helpers/src/lib.rs
index b80c745aaf2..51b860a8635 100644
--- a/crates/test_helpers/src/lib.rs
+++ b/crates/test_helpers/src/lib.rs
@@ -1,4 +1,8 @@
-#![feature(stdsimd, powerpc_target_feature)]
+#![feature(powerpc_target_feature)]
+#![cfg_attr(
+    any(target_arch = "powerpc", target_arch = "powerpc64"),
+    feature(stdarch_powerpc)
+)]
 
 pub mod array;