From 0df9721b02439f39203548f2754bffbf23f22709 Mon Sep 17 00:00:00 2001
From: Larry Ewing <lewing@microsoft.com>
Date: Fri, 25 Sep 2026 16:07:44 -0500
Subject: [PATCH 1/3] [wasm][coreclr] Strip R2R debug info by default for
 browser-wasm publish

Match the Apple mobile default: pass --strip-debug-info to crossgen2 for
CoreCLR browser-wasm ReadyToRun publish to minimize download size. Opt out
with PublishReadyToRunStripDebugInfo=false to keep IL offset maps and
variable locations for debugging R2R code.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
---
 .../Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets      | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets b/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets
index ef14fb88830085..036e640f70c12d 100644
--- a/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets
+++ b/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets
@@ -27,6 +27,9 @@ Copyright (c) .NET Foundation. All rights reserved.
     <PublishReadyToRunCrossgen2ExtraArgs>$(PublishReadyToRunCrossgen2ExtraArgs);--opt-cross-module:*</PublishReadyToRunCrossgen2ExtraArgs>
     <!-- NYI/SIMD methods crossgen2 can't emit into R2R fall back to the runtime JIT. -->
     <PublishReadyToRunCrossgen2ExtraArgs>$(PublishReadyToRunCrossgen2ExtraArgs);--codegenopt:JitWasmNyiToR2RUnsupported=1;--codegenopt:JitWasmSimdNyiToR2RUnsupported=1</PublishReadyToRunCrossgen2ExtraArgs>
+    <!-- Match Apple mobile: strip R2R debug info (IL offset maps and variable locations) to minimize download
+         size. Set PublishReadyToRunStripDebugInfo=false to keep it for debugging R2R code. -->
+    <PublishReadyToRunCrossgen2ExtraArgs Condition="'$(PublishReadyToRunStripDebugInfo)' != 'false'">$(PublishReadyToRunCrossgen2ExtraArgs);--strip-debug-info</PublishReadyToRunCrossgen2ExtraArgs>
   </PropertyGroup>
 
   <!-- Prebuilt R2R probe directory for ConvertDllsToWebcil. PublishTrimmed is deliberately not consulted:

From 209fa10c6ad78cb0327e387b530cef9a556f3134 Mon Sep 17 00:00:00 2001
From: Larry Ewing <lewing@microsoft.com>
Date: Fri, 25 Sep 2026 16:11:52 -0500
Subject: [PATCH 2/3] [wasm][coreclr] Invalidate R2R images when crossgen2
 arguments change

_CreateR2RImages only tracks file inputs, so toggling a crossgen2 argument
such as PublishReadyToRunStripDebugInfo left stale images in obj/R2R.
Stamp PublishReadyToRunCrossgen2ExtraArgs (written only when different)
and add it to _ReadyToRunCompilerInputs, mirroring the P/Invoke manifest.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
---
 ...soft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets b/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets
index 036e640f70c12d..a9c2516c0d036e 100644
--- a/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets
+++ b/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets
@@ -240,6 +240,19 @@ Copyright (c) .NET Foundation. All rights reserved.
       <_ReadyToRunCompilerInputs Include="$(_WasmResolvedCrossgen2Dir)crossgen2*;$(_WasmResolvedCrossgen2Dir)clrjit_universal_wasm_*"
                                  Condition="'$(_WasmResolvedCrossgen2Dir)' != ''" />
     </ItemGroup>
+    <!-- Crossgen2 arguments (e.g. toggling PublishReadyToRunStripDebugInfo) don't change any file input, so
+         stamp them; WriteOnlyWhenDifferent bumps the timestamp only when the arguments change. -->
+    <PropertyGroup>
+      <_WasmReadyToRunArgsStamp>$(IntermediateOutputPath)wasm-r2r-args.stamp</_WasmReadyToRunArgsStamp>
+    </PropertyGroup>
+    <WriteLinesToFile File="$(_WasmReadyToRunArgsStamp)"
+                      Lines="$(PublishReadyToRunCrossgen2ExtraArgs)"
+                      Overwrite="true"
+                      WriteOnlyWhenDifferent="true" />
+    <ItemGroup>
+      <_ReadyToRunCompilerInputs Include="$(_WasmReadyToRunArgsStamp)" />
+      <FileWrites Include="$(_WasmReadyToRunArgsStamp)" />
+    </ItemGroup>
   </Target>
 
   <!-- Delete per-app images and composite component stubs left in obj/R2R by a previous build or

From 0b6cc72ff4db0471fa45c42d488a9c67766dbd77 Mon Sep 17 00:00:00 2001
From: Larry Ewing <lewing@microsoft.com>
Date: Fri, 25 Sep 2026 18:00:23 -0500
Subject: [PATCH 3/3] Drop Apple mobile reference from strip-debug-info comment

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
---
 .../Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets     | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets b/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets
index a9c2516c0d036e..6a74a4b6f79156 100644
--- a/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets
+++ b/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.CoreCLR.targets
@@ -27,8 +27,8 @@ Copyright (c) .NET Foundation. All rights reserved.
     <PublishReadyToRunCrossgen2ExtraArgs>$(PublishReadyToRunCrossgen2ExtraArgs);--opt-cross-module:*</PublishReadyToRunCrossgen2ExtraArgs>
     <!-- NYI/SIMD methods crossgen2 can't emit into R2R fall back to the runtime JIT. -->
     <PublishReadyToRunCrossgen2ExtraArgs>$(PublishReadyToRunCrossgen2ExtraArgs);--codegenopt:JitWasmNyiToR2RUnsupported=1;--codegenopt:JitWasmSimdNyiToR2RUnsupported=1</PublishReadyToRunCrossgen2ExtraArgs>
-    <!-- Match Apple mobile: strip R2R debug info (IL offset maps and variable locations) to minimize download
-         size. Set PublishReadyToRunStripDebugInfo=false to keep it for debugging R2R code. -->
+    <!-- Strip R2R debug info (IL offset maps and variable locations) to minimize download size.
+         Set PublishReadyToRunStripDebugInfo=false to keep it for debugging R2R code. -->
     <PublishReadyToRunCrossgen2ExtraArgs Condition="'$(PublishReadyToRunStripDebugInfo)' != 'false'">$(PublishReadyToRunCrossgen2ExtraArgs);--strip-debug-info</PublishReadyToRunCrossgen2ExtraArgs>
   </PropertyGroup>