Prune features used by stdbuild

src/lib.rs

@@ -83,7 +83,7 @@
 ))]
 
 // Attributes needed when building as part of the standard library
-#![cfg_attr(stdbuild, feature(no_std, core, core_slice_ext, staged_api, custom_attribute, cfg_target_vendor))]
+#![cfg_attr(stdbuild, feature(no_std, staged_api, custom_attribute))]
 #![cfg_attr(stdbuild, feature(link_cfg))]
 #![cfg_attr(stdbuild, no_std)]
 #![cfg_attr(stdbuild, staged_api)]