Create a simple minimal MSBuild front-end (dotnet/coreclr#27778)

* Implement simple coreclr.proj msbuild entrypoint for building the coreclr product in the common configuration.

* Add dummy targets and automatically emit the enforcePGO argument when applicable.

* Add officialbuildId and stripSymbols arguments.

* Always pass the -stripsymbols argument.


Commit migrated from dotnet/coreclr@f1c282b

src/coreclr/build.sh

@@ -74,9 +74,6 @@ initTargetDistroRid()
     # Only pass ROOTFS_DIR if cross is specified.
     if (( ${__CrossBuild} == 1 )); then
         passedRootfsDir=${ROOTFS_DIR}
-    elif [ "${__BuildArch}" != "${__HostArch}" ]; then
-        echo "Error, you are building a cross scenario without passing -cross."
-        exit 1
     fi
 
     initDistroRidGlobal ${__BuildOS} ${__BuildArch} ${__PortableBuild} ${passedRootfsDir}
@@ -1037,6 +1034,10 @@ while :; do
     shift
 done
 
+if [ "${__BuildArch}" != "${__HostArch}" ]; then
+    __CrossBuild=1
+fi
+
 __CommonMSBuildArgs="/p:__BuildArch=$__BuildArch /p:__BuildType=$__BuildType /p:__BuildOS=$__BuildOS /nodeReuse:false $__OfficialBuildIdArg $__SignTypeArg $__SkipRestoreArg"
 
 # Configure environment if we are doing a verbose build

src/coreclr/coreclr.proj

@@ -0,0 +1,27 @@
+<Project>
+  <Import Project="Directory.Build.props" />
+  <Import Project="Directory.Build.targets" />
+
+  <Target Name="Build">
+    <ItemGroup>
+      <_CoreClrBuildArg Condition="$([MSBuild]::IsOsPlatform(Windows))" Include="-skiptests" />
+      <_CoreClrBuildArg Include="-$(Platform)" />
+      <_CoreClrBuildArg Include="-$(Configuration.ToLower())" />
+      <_CoreClrBuildArg Condition="'$(ContinuousIntegrationBuild)' == 'true'" Include="-ci" />
+      <_CoreClrBuildArg Condition="$([MSBuild]::IsOsPlatform(Windows)) and ('$(Platform)' == 'x86' or '$(Platform)' = 'x64') and '$(Configuration)' == 'Release'" Include="-enforcepgo" />
+      <_CoreClrBuildArg Condition="'$(Configuration)' == 'Release'" Include="-stripsymbols" />
+      <_CoreClrBuildArg Condition="'$(OfficialBuildId)' == ''" Include="-officialbuildid=$(OfficialBuildId)" />
+    </ItemGroup>
+
+    <PropertyGroup>
+      <_CoreClrBuildScript Condition="$([MSBuild]::IsOsPlatform(Windows))">build.cmd</_CoreClrBuildScript>
+      <_CoreClrBuildScript Condition="!$([MSBuild]::IsOsPlatform(Windows))">build.sh</_CoreClrBuildScript>
+    </PropertyGroup>
+
+    <Exec Command="&quot;$(MSBuildThisFileDirectory)$(_CoreClrBuildScript)&quot; @(_CoreClrBuildArg->'%(Identity)',' ')" />
+  </Target>
+
+  <Target Name="Restore" />
+  <Target Name="Test" />
+  <Target Name="Pack" />
+</Project>