Auto merge of #51990 - oli-obk:unstable_union, r=nikomatsakis

[rust.git] / src / libsyntax / feature_gate.rs

diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index 4aafe8bba58c1a7b0d7c79b7bc055bfcc48cb8da..6d71d276390c41308f2df8ceac80770963595301 100644 (file)
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -25,6 +25,7 @@
 use self::AttributeType::*;
 use self::AttributeGate::*;
 
+use rustc_data_structures::fx::FxHashMap;
 use rustc_target::spec::abi::Abi;
 use ast::{self, NodeId, PatKind, RangeEnd};
 use attr;
@@ -215,6 +216,18 @@ pub fn use_extern_macros(&self) -> bool {
     // Allows let bindings and destructuring in `const fn` functions and constants.
     (active, const_let, "1.22.1", Some(48821), None),
 
+    // Allows accessing fields of unions inside const fn
+    (active, const_fn_union, "1.27.0", Some(51909), None),
+
+    // Allows casting raw pointers to `usize` during const eval
+    (active, const_raw_ptr_to_usize_cast, "1.27.0", Some(51910), None),
+
+    // Allows dereferencing raw pointers during const eval
+    (active, const_raw_ptr_deref, "1.27.0", Some(51911), None),
+
+    // Allows comparing raw pointers during const eval
+    (active, const_compare_raw_pointers, "1.27.0", Some(53020), None),
+
     // Allows using #[prelude_import] on glob `use` items.
     //
     // rustc internal
@@ -321,9 +334,8 @@ pub fn use_extern_macros(&self) -> bool {
     // `extern "x86-interrupt" fn()`
     (active, abi_x86_interrupt, "1.17.0", Some(40180), None),
 
-
     // Allows the `catch {...}` expression
-    (active, catch_expr, "1.17.0", Some(31436), Some(Edition::Edition2018)),
+    (active, catch_expr, "1.17.0", Some(31436), None),
 
     // Used to preserve symbols (see llvm.used)
     (active, used, "1.18.0", Some(40289), None),
@@ -380,7 +392,7 @@ pub fn use_extern_macros(&self) -> bool {
     (active, crate_in_paths, "1.23.0", Some(45477), Some(Edition::Edition2018)),
 
     // In-band lifetime bindings (e.g. `fn foo(x: &'a u8) -> &'a u8`)
-    (active, in_band_lifetimes, "1.23.0", Some(44524), Some(Edition::Edition2018)),
+    (active, in_band_lifetimes, "1.23.0", Some(44524), None),
 
     // generic associated types (RFC 1598)
     (active, generic_associated_types, "1.23.0", Some(44265), None),
@@ -481,6 +493,10 @@ pub fn use_extern_macros(&self) -> bool {
     (active, alloc_error_handler, "1.29.0", Some(51540), None),
 
     (active, abi_amdgpu_kernel, "1.29.0", Some(51575), None),
+
+    // impl<I:Iterator> Iterator for &mut Iterator
+    // impl Debug for Foo<'_>
+    (active, impl_header_lifetime_elision, "1.30.0", Some(15872), Some(Edition::Edition2018)),
 );
 
 declare_features! (
@@ -1901,10 +1917,13 @@ fn feature_removed(span_handler: &Handler, span: Span, reason: Option<&str>) {
 
     let mut feature_checker = FeatureChecker::default();
 
-    for &(.., f_edition, set) in ACTIVE_FEATURES.iter() {
+    let mut edition_enabled_features = FxHashMap();
+
+    for &(name, .., f_edition, set) in ACTIVE_FEATURES.iter() {
         if let Some(f_edition) = f_edition {
             if f_edition <= crate_edition {
                 set(&mut features, DUMMY_SP);
+                edition_enabled_features.insert(Symbol::intern(name), crate_edition);
             }
         }
     }
@@ -1932,10 +1951,40 @@ fn feature_removed(span_handler: &Handler, span: Span, reason: Option<&str>) {
                 continue
             };
 
+            if let Some(edition) = ALL_EDITIONS.iter().find(|e| name == e.feature_name()) {
+                if *edition <= crate_edition {
+                    continue
+                }
+
+                for &(name, .., f_edition, set) in ACTIVE_FEATURES.iter() {
+                    if let Some(f_edition) = f_edition {
+                        if f_edition <= *edition {
+                            // FIXME(Manishearth) there is currently no way to set
+                            // lib features by edition
+                            set(&mut features, DUMMY_SP);
+                            edition_enabled_features.insert(Symbol::intern(name), *edition);
+                        }
+                    }
+                }
+
+                continue
+            }
+
             if let Some((.., set)) = ACTIVE_FEATURES.iter().find(|f| name == f.0) {
-                set(&mut features, mi.span);
-                feature_checker.collect(&features, mi.span);
-                features.declared_lang_features.push((name, mi.span, None));
+                if let Some(edition) = edition_enabled_features.get(&name) {
+                    struct_span_warn!(
+                        span_handler,
+                        mi.span,
+                        E0705,
+                        "the feature `{}` is included in the Rust {} edition",
+                        name,
+                        edition,
+                    ).emit();
+                } else {
+                    set(&mut features, mi.span);
+                    feature_checker.collect(&features, mi.span);
+                    features.declared_lang_features.push((name, mi.span, None));
+                }
                 continue
             }
 
@@ -1952,24 +2001,6 @@ fn feature_removed(span_handler: &Handler, span: Span, reason: Option<&str>) {
                 continue
             }
 
-            if let Some(edition) = ALL_EDITIONS.iter().find(|e| name == e.feature_name()) {
-                if *edition <= crate_edition {
-                    continue
-                }
-
-                for &(.., f_edition, set) in ACTIVE_FEATURES.iter() {
-                    if let Some(f_edition) = f_edition {
-                        if *edition >= f_edition {
-                            // FIXME(Manishearth) there is currently no way to set
-                            // lib features by edition
-                            set(&mut features, DUMMY_SP);
-                        }
-                    }
-                }
-
-                continue
-            }
-
             features.declared_lib_features.push((name, mi.span));
         }
     }