From fe5c4eab2dbc646f60f748b4b348acf5202ebf59 Mon Sep 17 00:00:00 2001
From: David Tolnay <dtolnay@gmail.com>
Date: Tue, 18 Jan 2022 19:23:22 -0800
Subject: [PATCH] Eliminate a check_stack call on an empty scan stack

---
 compiler/rustc_ast_pretty/src/pp.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler/rustc_ast_pretty/src/pp.rs b/compiler/rustc_ast_pretty/src/pp.rs
index d9832d560a841..21e685fff4a91 100644
--- a/compiler/rustc_ast_pretty/src/pp.rs
+++ b/compiler/rustc_ast_pretty/src/pp.rs
@@ -315,8 +315,8 @@ impl Printer {
         } else {
             self.right += 1;
             self.buf.advance_right();
+            self.check_stack(0);
         }
-        self.check_stack(0);
         self.buf[self.right] = BufEntry { token: Token::Break(b), size: -self.right_total };
         self.scan_stack.push_front(self.right);
         self.right_total += b.blank_space;