Ignore desugarings when comparing duplicate trait error messages

[rust.git] / src / librustc / hir / lowering.rs
diff --git a/src/librustc/hir/lowering.rs b/src/librustc/hir/lowering.rs

index bd8770abb135c55b0f77cc6ff0d21869a4e26af9..bf421da61e4437ce8868e47e53a6bbdf5c71a421 100644 (file)
--- a/src/librustc/hir/lowering.rs
+++ b/src/librustc/hir/lowering.rs
@@ -4058,16 +4058,16 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
                  // expand <head>
                  let head = self.lower_expr(head);
                  let head_sp = head.span;
+                let desugared_span = self.allow_internal_unstable(
+                    CompilerDesugaringKind::ForLoop,
+                    head_sp,
+                );
  
                  let iter = self.str_to_ident("iter");
  
                  let next_ident = self.str_to_ident("__next");
-                let next_sp = self.allow_internal_unstable(
-                    CompilerDesugaringKind::ForLoop,
-                    head_sp,
-                );
                  let next_pat = self.pat_ident_binding_mode(
-                    next_sp,
+                    desugared_span,
                      next_ident,
                      hir::BindingAnnotation::Mutable,
                  );
@@ -4096,8 +4096,11 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
                  };
  
                  // `mut iter`
-                let iter_pat =
-                    self.pat_ident_binding_mode(head_sp, iter, hir::BindingAnnotation::Mutable);
+                let iter_pat = self.pat_ident_binding_mode(
+                    desugared_span,
+                    iter,
+                    hir::BindingAnnotation::Mutable
+                );
  
                  // `match ::std::iter::Iterator::next(&mut iter) { ... }`
                  let match_expr = {
@@ -4126,8 +4129,12 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
                  let next_expr = P(self.expr_ident(head_sp, next_ident, next_pat.id));
  
                  // `let mut __next`
-                let next_let =
-                    self.stmt_let_pat(head_sp, None, next_pat, hir::LocalSource::ForLoopDesugar);
+                let next_let = self.stmt_let_pat(
+                    desugared_span,
+                    None,
+                    next_pat,
+                    hir::LocalSource::ForLoopDesugar,
+                );
  
                  // `let <pat> = __next`
                  let pat = self.lower_pat(pat);