Add toggle for `parse_meta_item` unsafe parsing

This makes it possible for the `unsafe(...)` syntax to only be
valid at the top level, and the `NestedMetaItem`s will automatically
reject `unsafe(...)`.

1 files changed, 1 insertions, 12 deletions

diff --git a/compiler/rustc_builtin_macros/src/derive.rs b/compiler/rustc_builtin_macros/src/derive.rs
index c540ff4e1de..57bddf0ab60 100644
--- a/compiler/rustc_builtin_macros/src/derive.rs
+++ b/compiler/rustc_builtin_macros/src/derive.rs
@@ -1,5 +1,5 @@
 use rustc_ast as ast;
-use rustc_ast::{GenericParamKind, ItemKind, MetaItemKind, NestedMetaItem, Safety, StmtKind};
+use rustc_ast::{GenericParamKind, ItemKind, MetaItemKind, NestedMetaItem, StmtKind};
 use rustc_expand::base::{
     Annotatable, DeriveResolution, ExpandResult, ExtCtxt, Indeterminate, MultiItemModifier,
 };
@@ -62,7 +62,6 @@ impl MultiItemModifier for Expander {
                                 // Reject `#[derive(Debug = "value", Debug(abc))]`, but recover the
                                 // paths.
                                 report_path_args(sess, meta);
-                                report_unsafe_args(sess, meta);
                                 meta.path.clone()
                             })
                             .map(|path| DeriveResolution {
@@ -162,13 +161,3 @@ fn report_path_args(sess: &Session, meta: &ast::MetaItem) {
         }
     }
 }
-
-fn report_unsafe_args(sess: &Session, meta: &ast::MetaItem) {
-    match meta.unsafety {
-        Safety::Unsafe(span) => {
-            sess.dcx().emit_err(errors::DeriveUnsafePath { span });
-        }
-        Safety::Default => {}
-        Safety::Safe(_) => unreachable!(),
-    }
-}