Add `const_trait_bound_opt_out` feature gate

diff --git a/src/librustc_feature/active.rs b/src/librustc_feature/active.rs
index 77ee9f40b6c714892420b5c71957bfc96c383a4c..6a15cc5cb0fceee67e147d867e5e619f343aeed4 100644 (file)
--- a/src/librustc_feature/active.rs
+++ b/src/librustc_feature/active.rs
@@ -547,6 +547,9 @@ pub fn set(&self, features: &mut Features, span: Span) {
     /// Allows `impl const Trait for T` syntax.
     (active, const_trait_impl, "1.42.0", Some(67792), None),
 
+    /// Allows `T: ?const Trait` syntax in bounds.
+    (active, const_trait_bound_opt_out, "1.42.0", Some(67794), None),
+
     // -------------------------------------------------------------------------
     // feature-group-end: actual feature gates
     // -------------------------------------------------------------------------
@@ -563,4 +566,5 @@ pub fn set(&self, features: &mut Features, span: Span) {
     sym::let_chains,
     sym::raw_dylib,
     sym::const_trait_impl,
+    sym::const_trait_bound_opt_out,
 ];

diff --git a/src/librustc_span/symbol.rs b/src/librustc_span/symbol.rs
index 5ba45e0a67399c42053f77542990dfaa4fca89b7..d9f4b72560ceb831f4d99db93ec25bb617936a79 100644 (file)
--- a/src/librustc_span/symbol.rs
+++ b/src/librustc_span/symbol.rs
@@ -219,6 +219,7 @@
         const_raw_ptr_deref,
         const_raw_ptr_to_usize_cast,
         const_transmute,
+        const_trait_bound_opt_out,
         const_trait_impl,
         contents,
         context,

diff --git a/src/libsyntax/feature_gate/check.rs b/src/libsyntax/feature_gate/check.rs
index f5090bf15536dc2a7998ca9eb06bd3da151081b1..52eb20d320f7be759adef09fac1e7ba95fa310d3 100644 (file)
--- a/src/libsyntax/feature_gate/check.rs
+++ b/src/libsyntax/feature_gate/check.rs
@@ -909,6 +909,7 @@ macro_rules! gate_all {
     gate_all!(or_patterns, "or-patterns syntax is experimental");
     gate_all!(const_extern_fn, "`const extern fn` definitions are unstable");
     gate_all!(raw_ref_op, "raw address of syntax is experimental");
+    gate_all!(const_trait_bound_opt_out, "`?const` on trait bounds is experimental");
     gate_all!(const_trait_impl, "const trait impls are experimental");
 
     // All uses of `gate_all!` below this point were added in #65742,