From ee97600a6f89963b08e1a16a36466a3d9b4783ba Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume.gomez@huawei.com>
Date: Tue, 28 Dec 2021 17:08:45 +0100
Subject: [PATCH 1/2] Fix invalid removal of backlines from doc comments

---
 compiler/rustc_ast/src/util/comments.rs                    | 7 -------
 .../rustdoc/mixing-doc-comments-and-attrs.S1_top-doc.html  | 4 ++--
 2 files changed, 2 insertions(+), 9 deletions(-)

diff --git a/compiler/rustc_ast/src/util/comments.rs b/compiler/rustc_ast/src/util/comments.rs
index 80a06fa594366..0a391123dd381 100644
--- a/compiler/rustc_ast/src/util/comments.rs
+++ b/compiler/rustc_ast/src/util/comments.rs
@@ -34,18 +34,11 @@ pub fn beautify_doc_string(data: Symbol) -> Symbol {
             i += 1;
         }
 
-        while i < j && lines[i].trim().is_empty() {
-            i += 1;
-        }
         // like the first, a last line of all stars should be omitted
         if j > i && !lines[j - 1].is_empty() && lines[j - 1].chars().all(|c| c == '*') {
             j -= 1;
         }
 
-        while j > i && lines[j - 1].trim().is_empty() {
-            j -= 1;
-        }
-
         if i != 0 || j != lines.len() { Some((i, j)) } else { None }
     }
 
diff --git a/src/test/rustdoc/mixing-doc-comments-and-attrs.S1_top-doc.html b/src/test/rustdoc/mixing-doc-comments-and-attrs.S1_top-doc.html
index 69d647a92e82b..8ff114b993edb 100644
--- a/src/test/rustdoc/mixing-doc-comments-and-attrs.S1_top-doc.html
+++ b/src/test/rustdoc/mixing-doc-comments-and-attrs.S1_top-doc.html
@@ -1,4 +1,4 @@
-<div class="docblock"><p>Hello world!
-Goodbye!
+<div class="docblock"><p>Hello world!</p>
+<p>Goodbye!
 Hello again!</p>
 </div>
\ No newline at end of file

From c6ee7bbe5197dbdec59acaab9b479f0610dfa5e1 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume.gomez@huawei.com>
Date: Sat, 1 Jan 2022 11:04:44 +0100
Subject: [PATCH 2/2] Update mixed doc comments test

---
 .../rustdoc/mixing-doc-comments-and-attrs.S3_top-doc.html  | 3 +++
 src/test/rustdoc/mixing-doc-comments-and-attrs.rs          | 7 +++++++
 2 files changed, 10 insertions(+)
 create mode 100644 src/test/rustdoc/mixing-doc-comments-and-attrs.S3_top-doc.html

diff --git a/src/test/rustdoc/mixing-doc-comments-and-attrs.S3_top-doc.html b/src/test/rustdoc/mixing-doc-comments-and-attrs.S3_top-doc.html
new file mode 100644
index 0000000000000..a4ee4b1418637
--- /dev/null
+++ b/src/test/rustdoc/mixing-doc-comments-and-attrs.S3_top-doc.html
@@ -0,0 +1,3 @@
+<div class="docblock"><p>Par 1</p>
+<p>Par 2</p>
+</div>
\ No newline at end of file
diff --git a/src/test/rustdoc/mixing-doc-comments-and-attrs.rs b/src/test/rustdoc/mixing-doc-comments-and-attrs.rs
index 1aedd4d107c21..a27c5ae6d0128 100644
--- a/src/test/rustdoc/mixing-doc-comments-and-attrs.rs
+++ b/src/test/rustdoc/mixing-doc-comments-and-attrs.rs
@@ -16,3 +16,10 @@ pub struct S1;
 #[doc = "Goodbye!"]
 /// Hello again!
 pub struct S2;
+
+// @has 'foo/struct.S3.html'
+// @snapshot S3_top-doc - '//details[@class="rustdoc-toggle top-doc"]/div[@class="docblock"]'
+/** Par 1
+*/ ///
+/// Par 2
+pub struct S3;