From fb04e3f082ea1b0354b20fcc33deff5501143416 Mon Sep 17 00:00:00 2001
From: Adeel Mujahid <3840695+am11@users.noreply.github.com>
Date: Fri, 17 Mar 2023 00:38:18 +0200
Subject: [PATCH 1/7] Prefer gold linker on linux

---
 .../Microsoft.NETCore.Native.Unix.targets         | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
index 4e18bb39e7f361..555c4fe60e90ea 100644
--- a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
+++ b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
@@ -190,6 +190,21 @@ The .NET Foundation licenses this file to you under the MIT license.
     <Error Condition="'$(_WhereLinker)' != '0' and '$(CppCompilerAndLinkerAlternative)' == '' and '$(_IsApplePlatform)' != 'true'"
       Text="Requested linker ('$(CppLinker)') not found in PATH." />
 
+    <![CDATA[
+      Testing if gold linker is available:
+        ! echo "" | cc -xc -fuse-ld=gold - 2>&1 | grep -qE "fuse-ld=gold|'ld'"
+    ]]>
+    <Exec Command="! echo &quot;&quot; | &quot;$(CppLinker)&quot; -xc -fuse-ld=gold - 2&gt;&amp;1 | grep -qE &quot;fuse-ld=gold|'ld'&quot;"
+          Condition="'$(UseLlvmLinker)' != 'true' and '$(_targetOS)' == 'linux'"
+          IgnoreExitCode="true"
+          StandardOutputImportance="Low">
+      <Output TaskParameter="ExitCode" PropertyName="_GoldLinkerSupportedExitCode" />
+    </Exec>
+
+    <ItemGroup>
+      <LinkerArg Include="-fuse-ld=gold" Condition="'$(_GoldLinkerSupportedExitCode)' == '0'" />
+    </ItemGroup>
+
     <Exec Command="command -v &quot;$(ObjCopyName)&quot;" IgnoreExitCode="true" StandardOutputImportance="Low" Condition="'$(_IsApplePlatform)' != 'true' and '$(StripSymbols)' == 'true'">
       <Output TaskParameter="ExitCode" PropertyName="_WhereSymbolStripper" />
     </Exec>

From 37455496852806edd224ef954238863aaab25c89 Mon Sep 17 00:00:00 2001
From: Adeel Mujahid <3840695+am11@users.noreply.github.com>
Date: Fri, 17 Mar 2023 01:28:22 +0200
Subject: [PATCH 2/7] Fix comment

---
 .../BuildIntegration/Microsoft.NETCore.Native.Unix.targets    | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
index 555c4fe60e90ea..5a99650b3e0247 100644
--- a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
+++ b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
@@ -190,10 +190,10 @@ The .NET Foundation licenses this file to you under the MIT license.
     <Error Condition="'$(_WhereLinker)' != '0' and '$(CppCompilerAndLinkerAlternative)' == '' and '$(_IsApplePlatform)' != 'true'"
       Text="Requested linker ('$(CppLinker)') not found in PATH." />
 
-    <![CDATA[
+    <!--
       Testing if gold linker is available:
         ! echo "" | cc -xc -fuse-ld=gold - 2>&1 | grep -qE "fuse-ld=gold|'ld'"
-    ]]>
+    -->
     <Exec Command="! echo &quot;&quot; | &quot;$(CppLinker)&quot; -xc -fuse-ld=gold - 2&gt;&amp;1 | grep -qE &quot;fuse-ld=gold|'ld'&quot;"
           Condition="'$(UseLlvmLinker)' != 'true' and '$(_targetOS)' == 'linux'"
           IgnoreExitCode="true"

From bef6056c3fe3263125b845298eae4180e353c793 Mon Sep 17 00:00:00 2001
From: Adeel Mujahid <3840695+am11@users.noreply.github.com>
Date: Fri, 17 Mar 2023 08:24:24 +0200
Subject: [PATCH 3/7] Try without gc-sections

---
 .../nativeaot/BuildIntegration/Microsoft.NETCore.Native.targets | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.targets b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.targets
index cf8f7e8805af0e..d4721c9476b42e 100644
--- a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.targets
+++ b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.targets
@@ -315,7 +315,7 @@ The .NET Foundation licenses this file to you under the MIT license.
     </ItemGroup>
     <ItemGroup Condition="'$(_targetOS)' != 'win' and '$(_IsApplePlatform)' != 'true'">
       <CustomLinkerArg Include="-Wl,--discard-all" />
-      <CustomLinkerArg Include="-Wl,--gc-sections" Condition="'$(UseLLVMLinker)' != 'true'" />
+      <CustomLinkerArg Include="-Wl,--gc-sections" Condition="'$(UseLLVMLinker)' != 'true' and '$(_GoldLinkerSupportedExitCode)' != '0'" />
     </ItemGroup>
     <ItemGroup>
       <CustomLibArg Include="-crs &quot;$(NativeBinary)&quot;" Condition="'$(_targetOS)' != 'win'" />

From 4e6bc060142702e51a114183b2248d5442cf5e17 Mon Sep 17 00:00:00 2001
From: Adeel Mujahid <3840695+am11@users.noreply.github.com>
Date: Fri, 17 Mar 2023 10:58:49 +0200
Subject: [PATCH 4/7] Add ability to specify linker via -p:LinkerFlavor

---
 .../Microsoft.NETCore.Native.Unix.targets     | 20 +++++++++----------
 .../Microsoft.NETCore.Native.targets          |  2 +-
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
index 5a99650b3e0247..4d42157fc61b60 100644
--- a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
+++ b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
@@ -21,7 +21,8 @@ The .NET Foundation licenses this file to you under the MIT license.
     <CppLibCreator>ar</CppLibCreator>
     <DsymUtilOptions Condition="'$(_IsApplePlatform)' == 'true'">--flat</DsymUtilOptions>
     <_SymbolPrefix Condition="'$(_IsApplePlatform)' == 'true'">_</_SymbolPrefix>
-    <UseLLVMLinker Condition="'$(UseLLVMLinker)' == '' and '$(_targetOS)' == 'freebsd'">true</UseLLVMLinker>
+    <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_targetOS)' == 'freebsd'">lld</LinkerFlavor>
+    <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_targetOS)' == 'linux'">bfd</LinkerFlavor>
   </PropertyGroup>
 
   <Target Name="SetupOSSpecificProps" DependsOnTargets="$(IlcDynamicBuildPropertyDependencies)">
@@ -112,7 +113,7 @@ The .NET Foundation licenses this file to you under the MIT license.
     </ItemGroup>
 
     <ItemGroup>
-      <LinkerArg Include="-fuse-ld=lld" Condition="'$(UseLLVMLinker)' == 'true'" />
+      <LinkerArg Include="-fuse-ld=$(LinkerFlavor)" Condition="'$(LinkerFlavor)' != ''" />
       <LinkerArg Include="@(NativeLibrary)" />
       <LinkerArg Include="--sysroot=$(SysRoot)" Condition="'$(SysRoot)' != ''" />
       <LinkerArg Include="--target=$(TargetTriple)" Condition="'$(_IsApplePlatform)' != 'true' and '$(TargetTriple)' != ''" />
@@ -148,8 +149,7 @@ The .NET Foundation licenses this file to you under the MIT license.
       <LinkerArg Include="-Wl,-z,relro" Condition="'$(_IsApplePlatform)' != 'true'" />
       <!-- binskim warning BA3011 The BIND_NOW flag is missing -->
       <LinkerArg Include="-Wl,-z,now" Condition="'$(_IsApplePlatform)' != 'true'" />
-      <LinkerArg Include="-Wl,-u,$(_SymbolPrefix)NativeAOT_StaticInitialization" Condition="('$(UseLLVMLinker)' == 'true' or '$(_IsApplePlatform)' == 'true' or '$(_targetOS)' == 'freebsd') and ('$(NativeLib)' == 'Shared' or '$(CustomNativeMain)' == 'true')" />
-      <LinkerArg Include="-Wl,--require-defined,NativeAOT_StaticInitialization" Condition="'$(UseLLVMLinker)' != 'true' and '$(_targetOS)' == 'linux' and ('$(NativeLib)' == 'Shared' or '$(CustomNativeMain)' == 'true')" />
+      <LinkerArg Include="-Wl,-u,$(_SymbolPrefix)NativeAOT_StaticInitialization" Condition="'$(LinkerFlavor)' == 'bfd' and ('$(NativeLib)' == 'Shared' or '$(CustomNativeMain)' == 'true')" />
       <!-- this workaround can be deleted once the minimum supported glibc version
            (runtime's official build machine's glibc version) is at least 2.33
            see https://github.com/bminor/glibc/commit/99468ed45f5a58f584bab60364af937eb6f8afda -->
@@ -191,18 +191,18 @@ The .NET Foundation licenses this file to you under the MIT license.
       Text="Requested linker ('$(CppLinker)') not found in PATH." />
 
     <!--
-      Testing if gold linker is available:
-        ! echo "" | cc -xc -fuse-ld=gold - 2>&1 | grep -qE "fuse-ld=gold|'ld'"
+      Testing if linker supports required-defined:
+        ! echo "" | cc -xc -fuse-ld=$LD -Wl,-require-defined,Foo - 2>&1 | grep -q '\-require-defined: unknown option'"
     -->
-    <Exec Command="! echo &quot;&quot; | &quot;$(CppLinker)&quot; -xc -fuse-ld=gold - 2&gt;&amp;1 | grep -qE &quot;fuse-ld=gold|'ld'&quot;"
-          Condition="'$(UseLlvmLinker)' != 'true' and '$(_targetOS)' == 'linux'"
+    <Exec Command="! echo &quot;&quot; | &quot;$(CppLinker)&quot; -xc -fuse-ld=$(LinkerFlavor) -Wl,--require-defined,Foo - 2&gt;&amp;1 | grep -q '\--require-defined: unknown option'"
+          Condition="'$(LinkerFlavor)' != 'lld' and '$(_targetOS)' == 'linux'"
           IgnoreExitCode="true"
           StandardOutputImportance="Low">
-      <Output TaskParameter="ExitCode" PropertyName="_GoldLinkerSupportedExitCode" />
+      <Output TaskParameter="ExitCode" PropertyName="_RequireOptionSupportedExitCode" />
     </Exec>
 
     <ItemGroup>
-      <LinkerArg Include="-fuse-ld=gold" Condition="'$(_GoldLinkerSupportedExitCode)' == '0'" />
+      <LinkerArg Include="-Wl,--require-defined,NativeAOT_StaticInitialization" Condition="'$(_RequireOptionSupportedExitCode)' == '0' and ('$(NativeLib)' == 'Shared' or '$(CustomNativeMain)' == 'true')" />
     </ItemGroup>
 
     <Exec Command="command -v &quot;$(ObjCopyName)&quot;" IgnoreExitCode="true" StandardOutputImportance="Low" Condition="'$(_IsApplePlatform)' != 'true' and '$(StripSymbols)' == 'true'">
diff --git a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.targets b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.targets
index d4721c9476b42e..c297b75546e60d 100644
--- a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.targets
+++ b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.targets
@@ -315,7 +315,7 @@ The .NET Foundation licenses this file to you under the MIT license.
     </ItemGroup>
     <ItemGroup Condition="'$(_targetOS)' != 'win' and '$(_IsApplePlatform)' != 'true'">
       <CustomLinkerArg Include="-Wl,--discard-all" />
-      <CustomLinkerArg Include="-Wl,--gc-sections" Condition="'$(UseLLVMLinker)' != 'true' and '$(_GoldLinkerSupportedExitCode)' != '0'" />
+      <CustomLinkerArg Include="-Wl,--gc-sections" Condition="'$(LinkerFlavor)' == '' or '$(LinkerFlavor)' == 'bfd'" />
     </ItemGroup>
     <ItemGroup>
       <CustomLibArg Include="-crs &quot;$(NativeBinary)&quot;" Condition="'$(_targetOS)' != 'win'" />

From 0f9768f8b874481dcfb6e744e314268daf0c4b7c Mon Sep 17 00:00:00 2001
From: Adeel Mujahid <3840695+am11@users.noreply.github.com>
Date: Fri, 17 Mar 2023 11:08:29 +0200
Subject: [PATCH 5/7] =?UTF-8?q?Straighten=20out=20the=20spaghetti=20?=
 =?UTF-8?q?=F0=9F=8D=9D?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../Microsoft.NETCore.Native.Unix.targets       | 17 +----------------
 1 file changed, 1 insertion(+), 16 deletions(-)

diff --git a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
index 4d42157fc61b60..8f270d1793ad67 100644
--- a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
+++ b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
@@ -149,7 +149,7 @@ The .NET Foundation licenses this file to you under the MIT license.
       <LinkerArg Include="-Wl,-z,relro" Condition="'$(_IsApplePlatform)' != 'true'" />
       <!-- binskim warning BA3011 The BIND_NOW flag is missing -->
       <LinkerArg Include="-Wl,-z,now" Condition="'$(_IsApplePlatform)' != 'true'" />
-      <LinkerArg Include="-Wl,-u,$(_SymbolPrefix)NativeAOT_StaticInitialization" Condition="'$(LinkerFlavor)' == 'bfd' and ('$(NativeLib)' == 'Shared' or '$(CustomNativeMain)' == 'true')" />
+      <LinkerArg Include="-Wl,-u,$(_SymbolPrefix)NativeAOT_StaticInitialization" Condition="'$(NativeLib)' == 'Shared' or '$(CustomNativeMain)' == 'true'" />
       <!-- this workaround can be deleted once the minimum supported glibc version
            (runtime's official build machine's glibc version) is at least 2.33
            see https://github.com/bminor/glibc/commit/99468ed45f5a58f584bab60364af937eb6f8afda -->
@@ -190,21 +190,6 @@ The .NET Foundation licenses this file to you under the MIT license.
     <Error Condition="'$(_WhereLinker)' != '0' and '$(CppCompilerAndLinkerAlternative)' == '' and '$(_IsApplePlatform)' != 'true'"
       Text="Requested linker ('$(CppLinker)') not found in PATH." />
 
-    <!--
-      Testing if linker supports required-defined:
-        ! echo "" | cc -xc -fuse-ld=$LD -Wl,-require-defined,Foo - 2>&1 | grep -q '\-require-defined: unknown option'"
-    -->
-    <Exec Command="! echo &quot;&quot; | &quot;$(CppLinker)&quot; -xc -fuse-ld=$(LinkerFlavor) -Wl,--require-defined,Foo - 2&gt;&amp;1 | grep -q '\--require-defined: unknown option'"
-          Condition="'$(LinkerFlavor)' != 'lld' and '$(_targetOS)' == 'linux'"
-          IgnoreExitCode="true"
-          StandardOutputImportance="Low">
-      <Output TaskParameter="ExitCode" PropertyName="_RequireOptionSupportedExitCode" />
-    </Exec>
-
-    <ItemGroup>
-      <LinkerArg Include="-Wl,--require-defined,NativeAOT_StaticInitialization" Condition="'$(_RequireOptionSupportedExitCode)' == '0' and ('$(NativeLib)' == 'Shared' or '$(CustomNativeMain)' == 'true')" />
-    </ItemGroup>
-
     <Exec Command="command -v &quot;$(ObjCopyName)&quot;" IgnoreExitCode="true" StandardOutputImportance="Low" Condition="'$(_IsApplePlatform)' != 'true' and '$(StripSymbols)' == 'true'">
       <Output TaskParameter="ExitCode" PropertyName="_WhereSymbolStripper" />
     </Exec>

From 94a9950166ad554b4851bbf937a71e7cb5e11aae Mon Sep 17 00:00:00 2001
From: Adeel Mujahid <3840695+am11@users.noreply.github.com>
Date: Fri, 17 Mar 2023 11:08:52 +0200
Subject: [PATCH 6/7] Switch to gold and see what breaks

---
 .../BuildIntegration/Microsoft.NETCore.Native.Unix.targets      | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
index 8f270d1793ad67..d8b6b22897f25b 100644
--- a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
+++ b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
@@ -22,7 +22,7 @@ The .NET Foundation licenses this file to you under the MIT license.
     <DsymUtilOptions Condition="'$(_IsApplePlatform)' == 'true'">--flat</DsymUtilOptions>
     <_SymbolPrefix Condition="'$(_IsApplePlatform)' == 'true'">_</_SymbolPrefix>
     <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_targetOS)' == 'freebsd'">lld</LinkerFlavor>
-    <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_targetOS)' == 'linux'">bfd</LinkerFlavor>
+    <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_targetOS)' == 'linux'">gold</LinkerFlavor>
   </PropertyGroup>
 
   <Target Name="SetupOSSpecificProps" DependsOnTargets="$(IlcDynamicBuildPropertyDependencies)">

From a41d903bae9644a603475195e34d1ac799bf7dbc Mon Sep 17 00:00:00 2001
From: Adeel Mujahid <3840695+am11@users.noreply.github.com>
Date: Fri, 17 Mar 2023 13:30:10 +0200
Subject: [PATCH 7/7] Set linux default to bfd

---
 .../BuildIntegration/Microsoft.NETCore.Native.Unix.targets      | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
index d8b6b22897f25b..8f270d1793ad67 100644
--- a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
+++ b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
@@ -22,7 +22,7 @@ The .NET Foundation licenses this file to you under the MIT license.
     <DsymUtilOptions Condition="'$(_IsApplePlatform)' == 'true'">--flat</DsymUtilOptions>
     <_SymbolPrefix Condition="'$(_IsApplePlatform)' == 'true'">_</_SymbolPrefix>
     <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_targetOS)' == 'freebsd'">lld</LinkerFlavor>
-    <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_targetOS)' == 'linux'">gold</LinkerFlavor>
+    <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_targetOS)' == 'linux'">bfd</LinkerFlavor>
   </PropertyGroup>
 
   <Target Name="SetupOSSpecificProps" DependsOnTargets="$(IlcDynamicBuildPropertyDependencies)">