Add Docker image for s390x (IBM Z System) cross-compile

manifest.json

@@ -461,6 +461,18 @@
             }
           ]
         },
+        {
+          "platforms": [
+            {
+              "dockerfile": "src/ubuntu/18.04/cross/s390x",
+              "os": "linux",
+              "osVersion": "bionic",
+              "tags": {
+                "ubuntu-18.04-cross-s390x-$(System:TimeStamp)-$(System:DockerfileGitCommitSha)": {}
+              }
+            }
+          ]
+        },
         {
           "platforms": [
             {

src/ubuntu/18.04/cross/s390x/Dockerfile

@@ -0,0 +1,9 @@
+FROM mcr.microsoft.com/dotnet-buildtools/prereqs:ubuntu-18.04-crossdeps
+
+# Install binutils-s390x-linux-gnu
+RUN apt-get update \
+    && apt-get install -y \
+        binutils-s390x-linux-gnu \
+    && rm -rf /var/lib/apt/lists/*
+
+ADD rootfs.s390x.tar crossrootfs

src/ubuntu/18.04/cross/s390x/hooks/post-build

@@ -0,0 +1,3 @@
+#!/usr/bin/env sh
+
+rm -rf $PWD/rootfs*.tar

src/ubuntu/18.04/cross/s390x/hooks/pre-build

@@ -0,0 +1,5 @@
+#!/usr/bin/env sh
+
+SCRIPT=$(readlink -f "$0")
+SCRIPTPATH=$(dirname "$SCRIPT")
+$SCRIPTPATH/../../../../build-scripts/build-rootfs.sh ubuntu-18.04 bionic s390x nolldb