From aea02409bb9a60f838e09f422ea04ec36c58c04a Mon Sep 17 00:00:00 2001
From: tony <57042389+tonydnewell@users.noreply.github.com>
Date: Mon, 16 Jan 2023 10:10:46 +0000
Subject: [PATCH] Use x86 protoc binaries on arm64 Windows (#32017)

---
 src/csharp/Grpc.Tools.Tests/ProtoToolsPlatformTaskTest.cs | 5 +++++
 src/csharp/Grpc.Tools/ProtoToolsPlatform.cs               | 5 +++++
 2 files changed, 10 insertions(+)

diff --git a/src/csharp/Grpc.Tools.Tests/ProtoToolsPlatformTaskTest.cs b/src/csharp/Grpc.Tools.Tests/ProtoToolsPlatformTaskTest.cs
index e98f6e93fa3..51b65c5bee8 100644
--- a/src/csharp/Grpc.Tools.Tests/ProtoToolsPlatformTaskTest.cs
+++ b/src/csharp/Grpc.Tools.Tests/ProtoToolsPlatformTaskTest.cs
@@ -79,6 +79,11 @@ namespace Grpc.Tools.Tests
                 {
                     Assert.AreEqual("x64", _task.Cpu);
                 }
+                // On windows arm64, x86 is used until a native protoc is shipped
+                else if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+                {
+                    Assert.AreEqual("x86", _task.Cpu);
+                }
                 else
                 {
                     Assert.AreEqual("arm64", _task.Cpu);
diff --git a/src/csharp/Grpc.Tools/ProtoToolsPlatform.cs b/src/csharp/Grpc.Tools/ProtoToolsPlatform.cs
index 2bccb0c3ba9..0bb57317b45 100644
--- a/src/csharp/Grpc.Tools/ProtoToolsPlatform.cs
+++ b/src/csharp/Grpc.Tools/ProtoToolsPlatform.cs
@@ -65,6 +65,11 @@ namespace Grpc.Tools
             {
                 Cpu = "x64";
             }
+            // Use x86 on Windows arm64 until a native protoc is shipped
+            else if (Os == "windows" && Cpu == "arm64")
+            {
+                Cpu = "x86";
+            }
 
             return true;
         }