From f57b97b06bd847630441940bc4096ffadc257717 Mon Sep 17 00:00:00 2001
From: Jean-Christophe Fillion-Robin <jchris.fillionr@kitware.com>
Date: Wed, 13 Apr 2016 19:24:04 -0400
Subject: [PATCH] linux-x86: Add toolchain file and install libc6 and stdc++6
 32-bit libraries

---
 linux-x86/Dockerfile           | 19 ++++++++++++++++---
 linux-x86/Toolchain.cmake      | 20 ++++++++++++++++++++
 linux-x86/i686-linux-gnu-as.sh |  2 ++
 3 files changed, 38 insertions(+), 3 deletions(-)
 create mode 100644 linux-x86/Toolchain.cmake
 create mode 100644 linux-x86/i686-linux-gnu-as.sh

diff --git a/linux-x86/Dockerfile b/linux-x86/Dockerfile
index 191bfab..c343852 100644
--- a/linux-x86/Dockerfile
+++ b/linux-x86/Dockerfile
@@ -4,18 +4,31 @@ MAINTAINER Matt McCormick "matt.mccormick@kitware.com"
 RUN dpkg --add-architecture i386 && \
   apt-get update && apt-get -y install \
     gcc-multilib \
-    g++-multilib
+    g++-multilib \
+    libc6:i386 \
+    libstdc++6:i386
 
 ENV CROSS_TRIPLE i686-linux-gnu
 ENV CROSS_ROOT /usr/${CROSS_TRIPLE}
 ENV PATH ${PATH}:${CROSS_ROOT}/bin
 RUN mkdir -p ${CROSS_ROOT}/bin
 COPY ${CROSS_TRIPLE}.sh ${CROSS_ROOT}/bin/${CROSS_TRIPLE}.sh
+COPY ${CROSS_TRIPLE}-as.sh ${CROSS_ROOT}/bin/${CROSS_TRIPLE}-as.sh
 RUN cd ${CROSS_ROOT}/bin && \
   chmod +x ${CROSS_TRIPLE}.sh && \
   ln -s /usr/bin/x86_64-linux-gnu-gcc && \
   ln -s /usr/bin/x86_64-linux-gnu-g++ && \
+  ln -s /usr/bin/x86_64-linux-gnu-as && \
   ln -s ${CROSS_TRIPLE}.sh ${CROSS_TRIPLE}-gcc && \
-  ln -s ${CROSS_TRIPLE}.sh ${CROSS_TRIPLE}-g++
-ENV CC=${CROSS_ROOT}/bin/${CROSS_TRIPLE}-gcc \
+  ln -s ${CROSS_TRIPLE}.sh ${CROSS_TRIPLE}-g++ && \
+  ln -s ${CROSS_TRIPLE}-as.sh ${CROSS_TRIPLE}-as && \
+  ln -s /usr/bin/x86_64-linux-gnu-ar ${CROSS_TRIPLE}-ar
+ENV AS=${CROSS_ROOT}/bin/${CROSS_TRIPLE}-as \
+    AR=${CROSS_ROOT}/bin/${CROSS_TRIPLE}-ar \
+    CC=${CROSS_ROOT}/bin/${CROSS_TRIPLE}-gcc \
     CXX=${CROSS_ROOT}/bin/${CROSS_TRIPLE}-g++
+
+# Note: Toolchain file support is currently in debian Experimental:
+# https://wiki.debian.org/CrossToolchains#In_jessie_.28Debian_8.29
+COPY Toolchain.cmake /usr/lib/${CROSS_TRIPLE}/
+ENV CMAKE_TOOLCHAIN_FILE /usr/lib/${CROSS_TRIPLE}/Toolchain.cmake
diff --git a/linux-x86/Toolchain.cmake b/linux-x86/Toolchain.cmake
new file mode 100644
index 0000000..0d4a74a
--- /dev/null
+++ b/linux-x86/Toolchain.cmake
@@ -0,0 +1,20 @@
+set(CMAKE_SYSTEM_NAME Linux)
+set(CMAKE_SYSTEM_VERSION 1)
+set(CMAKE_SYSTEM_PROCESSOR i686)
+
+# Setting these is not needed because the -m32 flag is already
+# associated with the ${cross_triple}-gcc wrapper script.
+#set(CMAKE_CXX_COMPILER_ARG1 "-m32")
+#set(CMAKE_C_COMPILER_ARG1 "-m32")
+
+set(cross_triple "i686-linux-gnu")
+
+set(CMAKE_C_COMPILER /usr/${cross_triple}/bin/${cross_triple}-gcc)
+set(CMAKE_CXX_COMPILER /usr/${cross_triple}/bin/${cross_triple}-g++)
+set(CMAKE_ASM_COMPILER ${CMAKE_C_COMPILER})
+set(CMAKE_AR /usr/${cross_triple}/bin/${cross_triple}-ar)
+
+# Prevent 64-bit libraries from being discovered
+set(CMAKE_IGNORE_PATH /usr/lib/x86_64-linux-gnu/ /usr/lib/x86_64-linux-gnu/lib/)
+
+set(CMAKE_CROSSCOMPILING_EMULATOR sh -c)
diff --git a/linux-x86/i686-linux-gnu-as.sh b/linux-x86/i686-linux-gnu-as.sh
new file mode 100644
index 0000000..8fc21ef
--- /dev/null
+++ b/linux-x86/i686-linux-gnu-as.sh
@@ -0,0 +1,2 @@
+#!/bin/bash
+exec ${0/${CROSS_TRIPLE}-/x86_64-linux-gnu-} --32 "$@"