temp

Author: aDotInTheVoid

compiler/rustc_const_eval/messages.ftl

@@ -385,6 +385,8 @@ const_eval_unreachable_unwind =
 const_eval_unsigned_offset_from_overflow =
     `ptr_offset_from_unsigned` called when first pointer has smaller offset than second: {$a_offset} < {$b_offset}
 const_eval_unsized_local = unsized locals are not supported
+
+const_eval_unstable_declared_here = `{$def_path}` declaired here
 const_eval_unstable_const_fn = `{$def_path}` is not yet stable as a const fn
 
 const_eval_unstable_in_stable =

compiler/rustc_const_eval/src/errors.rs

@@ -129,6 +129,9 @@ pub(crate) struct UnstableConstFn {
     #[primary_span]
     pub span: Span,
     pub def_path: String,
+
+    #[label(const_eval_declared_here)]
+    pub declared: Span,
 }
 
 #[derive(Diagnostic)]

compiler/rustc_const_eval/src/transform/check_consts/ops.rs

@@ -339,10 +339,11 @@ impl<'tcx> NonConstOp<'tcx> for FnCallUnstable {
     ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> {
         let FnCallUnstable(def_id, feature) = *self;
 
-        let mut err = ccx
-            .tcx
-            .sess
-            .create_err(errors::UnstableConstFn { span, def_path: ccx.tcx.def_path_str(def_id) });
+        let mut err = ccx.tcx.sess.create_err(errors::UnstableConstFn {
+            span,
+            def_path: ccx.tcx.def_path_str(def_id),
+            declared: ccx.tcx.def_span(def_id),
+        });
 
         if ccx.is_const_stable_const_fn() {
             err.help("const-stable functions can only call other const-stable functions");