Enable 'System.Private.CoreLib.dll' build on cross build mode (dotnet/coreclr#5320)

Currently, build.sh uses 'BuildOS' and 'BuildArch' to determine whether
it is possible to build 'System.Private.CorLib.dll'.

This commit revises build.sh to use 'HostOS' and 'HostArch' instead of
'BuildOS' and 'BuildArch' when it checkes whether it is possible to
build 'System.Private.CoreLib.dll', which allows to build
'System.Private.CoreLib.dll' in cross build mode.

Commit migrated from https://github.com/dotnet/coreclr/commit/376b1fc601bdb4f37acfb7937634c928d745ef18

diff --git a/src/coreclr/build.sh b/src/coreclr/build.sh
index 0e1f725..aa84a1b 100755 (executable)
--- a/src/coreclr/build.sh
+++ b/src/coreclr/build.sh
@@ -37,7 +37,7 @@ initDistroRid()
             export __DistroRid=""
         else
             source /etc/os-release
-            export __DistroRid="$ID.$VERSION_ID-$__BuildArch"
+            export __DistroRid="$ID.$VERSION_ID-$__HostArch"
         fi
     fi
 }
@@ -209,8 +209,8 @@ isMSBuildOnNETCoreSupported()
     # This needs to be updated alongwith corresponding changes to netci.groovy.
     __isMSBuildOnNETCoreSupported=0
 
-    if [ "$__BuildArch" == "x64" ]; then
-        if [ "$__BuildOS" == "Linux" ]; then
+    if [ "$__HostArch" == "x64" ]; then
+        if [ "$__HostOS" == "Linux" ]; then
             if [ "$__DistroRid" == "ubuntu.14.04-x64" ]; then
                 __isMSBuildOnNETCoreSupported=1
             elif [ "$__DistroRid" == "rhel.7.2-x64" ]; then
@@ -218,16 +218,9 @@ isMSBuildOnNETCoreSupported()
             elif [ "$__DistroRid" == "debian.8-x64" ]; then
                 __isMSBuildOnNETCoreSupported=1
             fi
-        elif [ "$__BuildOS" == "OSX" ]; then
+        elif [ "$__HostOS" == "OSX" ]; then
             __isMSBuildOnNETCoreSupported=1
         fi
-    elif [ "$__BuildArch" == "arm" ] || [ "$__BuildArch" == "arm-softfp" ] || [ "$__BuildArch" == "arm64" ] ; then
-        if [ "$__BuildOS" == "Linux" ]; then
-            if [ "$__DistroRid" == "ubuntu.14.04-x64" ]; then
-                __isMSBuildOnNETCoreSupported=1
-            fi
-        fi
-
     fi
 }
 
@@ -413,31 +406,38 @@ OSName=$(uname -s)
 case $OSName in
     Linux)
         __BuildOS=Linux
+        __HostOS=Linux
         ;;
 
     Darwin)
         __BuildOS=OSX
+        __HostOS=OSX
         ;;
 
     FreeBSD)
         __BuildOS=FreeBSD
+        __HostOS=FreeBSD
         ;;
 
     OpenBSD)
         __BuildOS=OpenBSD
+        __HostOS=OpenBSD
         ;;
 
     NetBSD)
         __BuildOS=NetBSD
+        __HostOS=NetBSD
         ;;
 
     SunOS)
         __BuildOS=SunOS
+        __HostOS=SunOS
         ;;
 
     *)
         echo "Unsupported OS $OSName detected, configuring as if for Linux"
         __BuildOS=Linux
+        __HostOS=Linux
         ;;
 esac