From f72b7046e5a7b2d0aa67bebd49b3f4d994c7e694 Mon Sep 17 00:00:00 2001
From: SoftCoder <mark_vejvoda@hotmail.com>
Date: Wed, 8 Jan 2014 21:19:14 -0800
Subject: [PATCH] - added experimental lunix32 cross compile support

---
 build-mg.sh                              | 20 ++++++++++++++++++--
 mk/cmake/Modules/Toolchain-linux32.cmake | 23 +++++++++++++++++++++++
 2 files changed, 41 insertions(+), 2 deletions(-)
 create mode 100644 mk/cmake/Modules/Toolchain-linux32.cmake

diff --git a/build-mg.sh b/build-mg.sh
index 96cd3ae60..ba83c5c53 100755
--- a/build-mg.sh
+++ b/build-mg.sh
@@ -19,8 +19,9 @@ MAKE_ONLY=0
 CLANG_FORCED=0
 WANT_STATIC_LIBS="-DWANT_STATIC_LIBS=ON"
 LUA_FORCED_VERSION=0
+FORCE_32BIT_CROSS_COMPILE=0
 
-while getopts "c:dfhl:mn" option; do
+while getopts "c:dfhl:mnx" option; do
    case "${option}" in
         c) 
            CPU_COUNT=${OPTARG}
@@ -36,7 +37,7 @@ while getopts "c:dfhl:mn" option; do
         ;;
         h) 
                 echo "Usage: $0 <option>"
-                echo "       where <option> can be: -c x, -d, -f, -m, -n, -h, -l x"
+                echo "       where <option> can be: -c x, -d, -f, -m, -n, -h, -l x, -x"
                 echo "       option descriptions:"
                 echo "       -c x : Force the cpu / cores count to x - example: -c 4"
                 echo "       -d   : Force DYNAMIC compile (do not want static libs)"
@@ -44,6 +45,8 @@ while getopts "c:dfhl:mn" option; do
                 echo "       -l x : Force using LUA version x - example: -l 51"                
                 echo "       -m   : Force running CMAKE only to create Make files (do not compile)"
                 echo "       -n   : Force running MAKE only to compile (assume CMAKE already built make files)"
+                echo "       -x   : Force cross compiling on x64 linux to produce an x86 32 bit binary"
+
                 echo "       -h   : Display this help usage"
 
         	exit 1        
@@ -60,6 +63,11 @@ while getopts "c:dfhl:mn" option; do
            MAKE_ONLY=1
 #           echo "${option} value: ${OPTARG}"
         ;;
+        x) 
+           FORCE_32BIT_CROSS_COMPILE=1
+#           echo "${option} value: ${OPTARG}"
+        ;;
+
         \?)
               echo "Script Invalid option: -$OPTARG" >&2
               exit 1
@@ -191,6 +199,14 @@ if [ $LUA_FORCED_VERSION != 0 ]; then
         fi
 fi
 
+if [ $FORCE_32BIT_CROSS_COMPILE != 0 ]; then
+        EXTRA_CMAKE_OPTIONS="${EXTRA_CMAKE_OPTIONS} -DCMAKE_TOOLCHAIN_FILE=../mk/cmake/Modules/Toolchain-linux32.cmake"
+
+#LIBDIR_32bit='/usr/lib32/'
+#export LD_LIBRARY_PATH="${LIBDIR_32bit}:${LD_LIBRARY_PATH}"
+
+fi
+
 if [ $MAKE_ONLY = 0 ]; then 
         echo "Calling cmake with EXTRA_CMAKE_OPTIONS = ${EXTRA_CMAKE_OPTIONS}"
         cmake -DCMAKE_INSTALL_PREFIX='' -DWANT_DEV_OUTPATH=ON $WANT_STATIC_LIBS -DBUILD_MEGAGLEST_TESTS=ON -DBREAKPAD_ROOT=$BREAKPAD_ROOT $EXTRA_CMAKE_OPTIONS ..
diff --git a/mk/cmake/Modules/Toolchain-linux32.cmake b/mk/cmake/Modules/Toolchain-linux32.cmake
new file mode 100644
index 000000000..644419039
--- /dev/null
+++ b/mk/cmake/Modules/Toolchain-linux32.cmake
@@ -0,0 +1,23 @@
+# Target operating system and architecture
+set( CMAKE_SYSTEM_NAME Linux )
+set( CMAKE_SYSTEM_PROCESSOR x86 )
+
+# C/C++ compilers
+#set( CMAKE_C_COMPILER gcc -m32 )
+#set( CMAKE_CXX_COMPILER g++ -m32 )
+SET( CMAKE_CXX_FLAGS  "${CMAKE_CXX_FLAGS} -m32" )
+SET( CMAKE_C_FLAGS  "${CMAKE_C_FLAGS} -m32" )
+
+#set( CMAKE_EXE_LINKER_FLAGS ${CMAKE_EXE_LINKER_FLAGS} -m32)
+#set( CMAKE_MODULE_LINKER_FLAGS ${CMAKE_MODULE_LINKER_FLAGS} -m32)
+#set( CMAKE_SHARED_LINKER_FLAGS ${CMAKE_SHARED_LINKER_FLAGS} -m32)
+
+# Only look for libraries in lib32
+set( CMAKE_SYSTEM_LIBRARY_PATH /lib32 /usr/lib32 /usr/local/lib32 )
+set_property( GLOBAL PROPERTY FIND_LIBRARY_USE_LIB64_PATHS OFF )
+set( CMAKE_IGNORE_PATH /lib /usr/lib /usr/local/lib )
+
+#set(CMAKE_FIND_ROOT_PATH  /usr/lib32)
+#set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+#set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+#set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)