From d0a6283075402060e5dec3bac8be101b942b98c3 Mon Sep 17 00:00:00 2001
From: Josef Pihrt <josef@pihrt.net>
Date: Wed, 8 May 2024 20:00:04 +0200
Subject: [PATCH 1/2] update

---
 .../Analysis/UseAutoPropertyAnalyzer.cs       |  2 +-
 .../RCS1085UseAutoPropertyTests.cs            | 29 +++++++++++++++++++
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/src/Analyzers/CSharp/Analysis/UseAutoPropertyAnalyzer.cs b/src/Analyzers/CSharp/Analysis/UseAutoPropertyAnalyzer.cs
index 422e2e1b58..16db72c43d 100644
--- a/src/Analyzers/CSharp/Analysis/UseAutoPropertyAnalyzer.cs
+++ b/src/Analyzers/CSharp/Analysis/UseAutoPropertyAnalyzer.cs
@@ -486,7 +486,7 @@ public override void VisitArgument(ArgumentSyntax node)
         {
             CancellationToken.ThrowIfCancellationRequested();
 
-            if (node.RefOrOutKeyword.IsKind(SyntaxKind.RefKeyword, SyntaxKind.OutKeyword))
+            if (node.RefOrOutKeyword.IsKind(SyntaxKind.RefKeyword, SyntaxKind.OutKeyword, SyntaxKind.InKeyword))
             {
                 ExpressionSyntax expression = node.Expression?.WalkDownParentheses();
 
diff --git a/src/Tests/Analyzers.Tests/RCS1085UseAutoPropertyTests.cs b/src/Tests/Analyzers.Tests/RCS1085UseAutoPropertyTests.cs
index a65b724594..3b72a81dbc 100644
--- a/src/Tests/Analyzers.Tests/RCS1085UseAutoPropertyTests.cs
+++ b/src/Tests/Analyzers.Tests/RCS1085UseAutoPropertyTests.cs
@@ -952,4 +952,33 @@ class C
 }
 ");
     }
+
+    [Fact, Trait(Traits.Analyzer, DiagnosticIdentifiers.UseAutoProperty)]
+    public async Task TestNoDiagnostic_BackingFieldUsedByReference()
+    {
+        await VerifyNoDiagnosticAsync(@"
+using System.Buffers;
+
+class Repro(ReadOnlySequence<byte> data)
+{
+    public ReadOnlySequence<byte> Data => _data;
+    private readonly ReadOnlySequence<byte> _data = data;
+
+    public void Method(IBufferWriter<byte> writer)
+    {
+        Write1(in _data, writer);
+        Write2(in _data, writer);
+    }
+
+    private static void Write1(in ReadOnlySequence<byte> data, IBufferWriter<byte> writer)
+    {
+        data.CopyTo(writer.GetSpan((int)data.Length));
+    }
+
+    private static void Write2(ref readonly ReadOnlySequence<byte> data, IBufferWriter<byte> writer)
+    {
+        data.CopyTo(writer.GetSpan((int)data.Length));
+    }
+}");
+    }
 }

From cbccc8e05419ae13f6e4f01ee2addf868887d118 Mon Sep 17 00:00:00 2001
From: Josef Pihrt <josef@pihrt.net>
Date: Wed, 8 May 2024 20:02:09 +0200
Subject: [PATCH 2/2] update

---
 ChangeLog.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/ChangeLog.md b/ChangeLog.md
index 0f8f0a1952..0d37f6011c 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+
+- Fix analyzer [RCS1085](https://josefpihrt.github.io/docs/roslynator/analyzers/RCS1085) ([PR](https://github.com/dotnet/roslynator/pull/1461))
+
 ## [4.12.2] - 2024-04-23
 
 ### Fixed