From e969b2809164f6ca95882dcb5b4f70fccc255e09 Mon Sep 17 00:00:00 2001
From: "dotnet-maestro[bot]" <dotnet-maestro[bot]@users.noreply.github.com>
Date: Wed, 22 Jul 2026 02:03:57 +0000
Subject: [PATCH 1/2] Update dependencies from
 https://github.com/dotnet/msbuild build 20260721.8 On relative base path root
 Microsoft.Build , Microsoft.Build.Framework , Microsoft.Build.Tasks.Core ,
 Microsoft.Build.Utilities.Core From Version 18.10.0-1.26370.18 -> To Version
 18.10.0-1.26371.8

---
 eng/Version.Details.props |  8 ++++----
 eng/Version.Details.xml   | 16 ++++++++--------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/eng/Version.Details.props b/eng/Version.Details.props
index 8af19d96d15..37c14dc319f 100644
--- a/eng/Version.Details.props
+++ b/eng/Version.Details.props
@@ -8,10 +8,10 @@ This file should be imported by eng/Versions.props
     <!-- dotnet-arcade dependencies -->
     <MicrosoftDotNetArcadeSdkPackageVersion>10.0.0-beta.26324.4</MicrosoftDotNetArcadeSdkPackageVersion>
     <!-- dotnet-msbuild dependencies -->
-    <MicrosoftBuildPackageVersion>18.10.0-1.26370.18</MicrosoftBuildPackageVersion>
-    <MicrosoftBuildFrameworkPackageVersion>18.10.0-1.26370.18</MicrosoftBuildFrameworkPackageVersion>
-    <MicrosoftBuildTasksCorePackageVersion>18.10.0-1.26370.18</MicrosoftBuildTasksCorePackageVersion>
-    <MicrosoftBuildUtilitiesCorePackageVersion>18.10.0-1.26370.18</MicrosoftBuildUtilitiesCorePackageVersion>
+    <MicrosoftBuildPackageVersion>18.10.0-1.26371.8</MicrosoftBuildPackageVersion>
+    <MicrosoftBuildFrameworkPackageVersion>18.10.0-1.26371.8</MicrosoftBuildFrameworkPackageVersion>
+    <MicrosoftBuildTasksCorePackageVersion>18.10.0-1.26371.8</MicrosoftBuildTasksCorePackageVersion>
+    <MicrosoftBuildUtilitiesCorePackageVersion>18.10.0-1.26371.8</MicrosoftBuildUtilitiesCorePackageVersion>
     <!-- dotnet-optimization dependencies -->
     <optimizationlinuxarm64MIBCRuntimePackageVersion>1.0.0-prerelease.26318.1</optimizationlinuxarm64MIBCRuntimePackageVersion>
     <optimizationlinuxx64MIBCRuntimePackageVersion>1.0.0-prerelease.26318.1</optimizationlinuxx64MIBCRuntimePackageVersion>
diff --git a/eng/Version.Details.xml b/eng/Version.Details.xml
index 61d4682124e..adef1d60f3c 100644
--- a/eng/Version.Details.xml
+++ b/eng/Version.Details.xml
@@ -2,21 +2,21 @@
 <Dependencies>
   <Source Uri="https://github.com/dotnet/dotnet" Mapping="fsharp" Sha="1358fe9202089df7bdb79282a191c9dbbb773a06" BarId="320196" />
   <ProductDependencies>
-    <Dependency Name="Microsoft.Build" Version="18.10.0-1.26370.18">
+    <Dependency Name="Microsoft.Build" Version="18.10.0-1.26371.8">
       <Uri>https://github.com/dotnet/msbuild</Uri>
-      <Sha>eae54023463db15e9a9081f35a959c9162797643</Sha>
+      <Sha>a3f26c8a893be2590fe1a2aac954539065e2b7db</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.Build.Framework" Version="18.10.0-1.26370.18">
+    <Dependency Name="Microsoft.Build.Framework" Version="18.10.0-1.26371.8">
       <Uri>https://github.com/dotnet/msbuild</Uri>
-      <Sha>eae54023463db15e9a9081f35a959c9162797643</Sha>
+      <Sha>a3f26c8a893be2590fe1a2aac954539065e2b7db</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.Build.Tasks.Core" Version="18.10.0-1.26370.18">
+    <Dependency Name="Microsoft.Build.Tasks.Core" Version="18.10.0-1.26371.8">
       <Uri>https://github.com/dotnet/msbuild</Uri>
-      <Sha>eae54023463db15e9a9081f35a959c9162797643</Sha>
+      <Sha>a3f26c8a893be2590fe1a2aac954539065e2b7db</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.Build.Utilities.Core" Version="18.10.0-1.26370.18">
+    <Dependency Name="Microsoft.Build.Utilities.Core" Version="18.10.0-1.26371.8">
       <Uri>https://github.com/dotnet/msbuild</Uri>
-      <Sha>eae54023463db15e9a9081f35a959c9162797643</Sha>
+      <Sha>a3f26c8a893be2590fe1a2aac954539065e2b7db</Sha>
     </Dependency>
     <Dependency Name="Microsoft.CodeAnalysis" Version="5.10.0-1.26365.3">
       <Uri>https://github.com/dotnet/roslyn</Uri>

From 3cf32a5920d7675370f5a6617e28f97d45bbde0c Mon Sep 17 00:00:00 2001
From: Copilot <copilot@github.com>
Date: Wed, 22 Jul 2026 19:32:22 +0200
Subject: [PATCH 2/2] Pin MSBuild at 18.10.0-1.26370.18 (last
 net10.0-compatible build)

The 18.10.0-1.26371.x MSBuild builds dropped their net10.0 assets (they now ship net11.0 + net472 only). This repo's product target framework is net10.0, so:

- The package's TFM-support check turns into a build error (doesn't support net10.0).
- More importantly, there is no net10.0 runtime asset, so the bootstrap fsc (and fsi) fail at runtime with a silent exit 1 when the legacy MSBuild reference resolver tries to load Microsoft.Build.Utilities.Core, breaking the FSharp.Core compilation and thus the whole build.

The net11.0 assemblies cannot be cleanly deployed to a net10.0 app (NuGet won't select them as runtime assets and manual deployment isn't reflected in deps.json), so the update cannot be consumed until the product moves to net11.0 or MSBuild restores net10.0 assets. Pin the dependencies at the last good build to keep CI green and stop the incompatible builds from re-flowing.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 eng/Version.Details.props | 11 ++++++-----
 eng/Version.Details.xml   | 20 ++++++++++++--------
 2 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/eng/Version.Details.props b/eng/Version.Details.props
index 37c14dc319f..b08cea14976 100644
--- a/eng/Version.Details.props
+++ b/eng/Version.Details.props
@@ -7,11 +7,12 @@ This file should be imported by eng/Versions.props
   <PropertyGroup>
     <!-- dotnet-arcade dependencies -->
     <MicrosoftDotNetArcadeSdkPackageVersion>10.0.0-beta.26324.4</MicrosoftDotNetArcadeSdkPackageVersion>
-    <!-- dotnet-msbuild dependencies -->
-    <MicrosoftBuildPackageVersion>18.10.0-1.26371.8</MicrosoftBuildPackageVersion>
-    <MicrosoftBuildFrameworkPackageVersion>18.10.0-1.26371.8</MicrosoftBuildFrameworkPackageVersion>
-    <MicrosoftBuildTasksCorePackageVersion>18.10.0-1.26371.8</MicrosoftBuildTasksCorePackageVersion>
-    <MicrosoftBuildUtilitiesCorePackageVersion>18.10.0-1.26371.8</MicrosoftBuildUtilitiesCorePackageVersion>
+    <!-- dotnet-msbuild dependencies. Pinned at 18.10.0-1.26370.18 (see eng/Version.Details.xml):
+         later 18.10.0-1.26371.x builds dropped net10.0 assets and are incompatible with our net10.0 target. -->
+    <MicrosoftBuildPackageVersion>18.10.0-1.26370.18</MicrosoftBuildPackageVersion>
+    <MicrosoftBuildFrameworkPackageVersion>18.10.0-1.26370.18</MicrosoftBuildFrameworkPackageVersion>
+    <MicrosoftBuildTasksCorePackageVersion>18.10.0-1.26370.18</MicrosoftBuildTasksCorePackageVersion>
+    <MicrosoftBuildUtilitiesCorePackageVersion>18.10.0-1.26370.18</MicrosoftBuildUtilitiesCorePackageVersion>
     <!-- dotnet-optimization dependencies -->
     <optimizationlinuxarm64MIBCRuntimePackageVersion>1.0.0-prerelease.26318.1</optimizationlinuxarm64MIBCRuntimePackageVersion>
     <optimizationlinuxx64MIBCRuntimePackageVersion>1.0.0-prerelease.26318.1</optimizationlinuxx64MIBCRuntimePackageVersion>
diff --git a/eng/Version.Details.xml b/eng/Version.Details.xml
index adef1d60f3c..3ed68c496a6 100644
--- a/eng/Version.Details.xml
+++ b/eng/Version.Details.xml
@@ -2,21 +2,25 @@
 <Dependencies>
   <Source Uri="https://github.com/dotnet/dotnet" Mapping="fsharp" Sha="1358fe9202089df7bdb79282a191c9dbbb773a06" BarId="320196" />
   <ProductDependencies>
-    <Dependency Name="Microsoft.Build" Version="18.10.0-1.26371.8">
+    <!-- Pinned at 18.10.0-1.26370.18: the 18.10.0-1.26371.x MSBuild builds dropped their net10.0
+         assets (they ship net11.0 + net472 only), which is incompatible with this repo's net10.0
+         product target framework - fsc/fsi fail to load Microsoft.Build.* at runtime. Unpin once
+         the product moves to net11.0 or MSBuild restores net10.0 assets. -->
+    <Dependency Name="Microsoft.Build" Version="18.10.0-1.26370.18" Pinned="true">
       <Uri>https://github.com/dotnet/msbuild</Uri>
-      <Sha>a3f26c8a893be2590fe1a2aac954539065e2b7db</Sha>
+      <Sha>eae54023463db15e9a9081f35a959c9162797643</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.Build.Framework" Version="18.10.0-1.26371.8">
+    <Dependency Name="Microsoft.Build.Framework" Version="18.10.0-1.26370.18" Pinned="true">
       <Uri>https://github.com/dotnet/msbuild</Uri>
-      <Sha>a3f26c8a893be2590fe1a2aac954539065e2b7db</Sha>
+      <Sha>eae54023463db15e9a9081f35a959c9162797643</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.Build.Tasks.Core" Version="18.10.0-1.26371.8">
+    <Dependency Name="Microsoft.Build.Tasks.Core" Version="18.10.0-1.26370.18" Pinned="true">
       <Uri>https://github.com/dotnet/msbuild</Uri>
-      <Sha>a3f26c8a893be2590fe1a2aac954539065e2b7db</Sha>
+      <Sha>eae54023463db15e9a9081f35a959c9162797643</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.Build.Utilities.Core" Version="18.10.0-1.26371.8">
+    <Dependency Name="Microsoft.Build.Utilities.Core" Version="18.10.0-1.26370.18" Pinned="true">
       <Uri>https://github.com/dotnet/msbuild</Uri>
-      <Sha>a3f26c8a893be2590fe1a2aac954539065e2b7db</Sha>
+      <Sha>eae54023463db15e9a9081f35a959c9162797643</Sha>
     </Dependency>
     <Dependency Name="Microsoft.CodeAnalysis" Version="5.10.0-1.26365.3">
       <Uri>https://github.com/dotnet/roslyn</Uri>