Yeet E0744

compiler/rustc_error_codes/src/error_codes.rs

@@ -653,3 +653,4 @@ E0795: include_str!("./error_codes/E0795.md"),
 //  E0721, // `await` keyword
 //  E0723, // unstable feature in `const` context
 //  E0738, // Removed; errored on `#[track_caller] fn`s in `extern "Rust" { ... }`.
+//  E0744, // merged into E0728

compiler/rustc_error_codes/src/error_codes/E0744.md

@@ -1,8 +1,10 @@
+#### Note: this error code is no longer emitted by the compiler.
+
 An unsupported expression was used inside a const context.
 
 Erroneous code example:
 
-```compile_fail,edition2018,E0744
+```ignore (removed error code)
 const _: i32 = {
     async { 0 }.await
 };

compiler/rustc_passes/src/check_const.rs

@@ -17,7 +17,7 @@ use rustc_middle::ty::TyCtxt;
 use rustc_session::parse::feature_err;
 use rustc_span::{sym, Span, Symbol};
 
-use crate::errors::{ExprNotAllowedInContext, SkippingConstChecks};
+use crate::errors::SkippingConstChecks;
 
 /// An expression that is not *always* legal in a const context.
 #[derive(Clone, Copy)]
@@ -138,11 +138,10 @@ impl<'tcx> CheckConstVisitor<'tcx> {
 
         match missing_gates.as_slice() {
             [] => {
-                tcx.sess.emit_err(ExprNotAllowedInContext {
+                span_bug!(
                     span,
-                    expr: expr.name(),
-                    context: const_kind.keyword_name(),
-                });
+                    "we should not have reached this point, since `.await` is denied earlier"
+                );
             }
 
             [missing_primary, ref missing_secondary @ ..] => {

compiler/rustc_passes/src/errors.rs

@@ -1005,15 +1005,6 @@ pub struct FeaturePreviouslyDeclared<'a, 'b> {
     pub prev_declared: &'b str,
 }
 
-#[derive(Diagnostic)]
-#[diag(passes_expr_not_allowed_in_context, code = "E0744")]
-pub struct ExprNotAllowedInContext<'a> {
-    #[primary_span]
-    pub span: Span,
-    pub expr: String,
-    pub context: &'a str,
-}
-
 pub struct BreakNonLoop<'a> {
     pub span: Span,
     pub head: Option<Span>,