Ubuntu 14.04 LTS，32-bit安装Torch7
环境：
主机系统：windows 10，64-bit
虚拟机：VMware Worksation 12.5.0
虚拟系统：ubuntu 14.04 LTS，32-bit
官网：
先给出官网的安装步骤：
# in a terminal, run the commands WITHOUT sudo
git clone https://github.com/torch/distro.git ~/torch --recursive
cd ~/torch
bash install-deps
./install.sh
source ~/.bashrc
然后下面是自己的安装过程，包括在安装过程中遇到的问题以及解决办法，希望对读者有所帮助。
Step1：
由于是刚安装的虚拟机，我们需要先安装git：sudo apt-get install git
然后运行：git clone https://github.com/torch/distro.git ~/torch --recursive
这一步若有问题的话，多半是网络问题，多试几次。
Step2:（OpenBLAS could not be compiled）
然后进入torch目录：cd ~/torch
安装基础包：bash install-deps
这个时候出现了下面的问题：
ar: strmm_kernel_LN.o: No such file or directory
make[1]: *** [libs] Error 1
make[1]: Leaving directory `/tmp/OpenBLAS/kernel'
make: *** [libs] Error 1
Error. OpenBLAS could not be compiled
解决方法：
sudo apt-get install vim #安装过vim的忽略此命令
vim ~/torch/install-deps
这时你会看见（15-19行）：
if [ $(getconf _NPROCESSORS_CONF) == 1 ]; then
make NO_AFFINITY=1 USE_OPENMP=0 USE_THREAD=0
else
make NO_AFFINITY=1 USE_OPENMP=1
fi
键入i进入插入模式，在make语句后面添加BINARY=32，修改后结果如下：
if [ $(getconf _NPROCESSORS_CONF) == 1 ]; then
make NO_AFFINITY=1 USE_OPENMP=0 USE_THREAD=0 BINARY=32
else
make NO_AFFINITY=1 USE_OPENMP=1 BINARY=32
fi
修改完成后，按下ESC，键入:wq保存退出，重新执行bash instal-deps即可完成安装：
···
Generating OpenBLASConfig.cmake in /opt/OpenBLAS/lib/cmake/openblas
Generating OpenBLASConfigVersion.cmake in /opt/OpenBLAS/lib/cmake/openblas
Install OK!
make[1]: Leaving directory `/tmp/OpenBLAS'
==> Torch7's dependencies have been installed
相关链接1：
https://github.com/xianyi/OpenBLAS/issues/657
https://github.com/xianyi/OpenBLAS/issues/1106
OpenBLAS编译和安装简介
Step3：(inconsistent operand constraints in an 'asm')
安装LuaJIT、LuaRocks等包：./install.sh
出现错误如下：
···
Scanning dependencies of target TH
[ 2%] Building C object lib/TH/CMakeFiles/TH.dir/THGeneral.c.o
[ 5%] Building C object lib/TH/CMakeFiles/TH.dir/THHalf.c.o
[ 8%] Building C object lib/TH/CMakeFiles/TH.dir/THAllocator.c.o
[ 11%] Building C object lib/TH/CMakeFiles/TH.dir/THStorage.c.o
[ 14%] Building C object lib/TH/CMakeFiles/TH.dir/THTensor.c.o
[ 17%] Building C object lib/TH/CMakeFiles/TH.dir/THBlas.c.o
[ 20%] Building C object lib/TH/CMakeFiles/TH.dir/THLapack.c.o
[ 22%] Building C object lib/TH/CMakeFiles/TH.dir/THLogAdd.c.o
[ 25%] Building C object lib/TH/CMakeFiles/TH.dir/THRandom.c.o
[ 28%] Building C object lib/TH/CMakeFiles/TH.dir/THFile.c.o
[ 31%] Building C object lib/TH/CMakeFiles/TH.dir/THDiskFile.c.o
[ 34%] Building C object lib/TH/CMakeFiles/TH.dir/THMemoryFile.c.o
[ 37%] Building C object lib/TH/CMakeFiles/TH.dir/THAtomic.c.o
[ 40%] Building C object lib/TH/CMakeFiles/TH.dir/THVector.c.o
In file included from /home/yang/torch/pkg/torch/lib/TH/THVector.c:3:0:
/home/yang/torch/pkg/torch/lib/TH/generic/THVectorDispatch.c: In function ‘THFloatVector_vectorDispatchInit’:
/home/yang/torch/pkg/torch/lib/TH/generic/simd/simd.h:108:3: error: inconsistent operand constraints in an ‘asm’
asm volatile ( "cpuid\n\t"
^
/home/yang/torch/pkg/torch/lib/TH/generic/simd/simd.h:108:3: error: inconsistent operand constraints in an ‘asm’
asm volatile ( "cpuid\n\t"
^
make[2]: *** [lib/TH/CMakeFiles/TH.dir/THVector.c.o] Error 1
make[1]: *** [lib/TH/CMakeFiles/TH.dir/all] Error 2
make: *** [all] Error 2
Error: Build error: Failed building.
解决方法：
ubuntu 14.04默认gcc版本是gcc-4.8，需要升级至gcc-5：
sudo add-apt-repository ppa:ubuntu-toolchain-r/test
sudo apt-get update
sudo apt-get install gcc-5 g++-5
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-5 60 --slave /usr/bin/g++ g++ /usr/bin/g++-5
gcc升级后，重新执行./install.sh即可完成安装：
···
Do you want to automatically prepend the Torch install location
to PATH and LD_LIBRARY_PATH in your /home/yang/.bashrc? (yes/no)
[yes] >>>
键入yes后，刷新你的环境变量：source ~/.bashrc
再键入th命令，可看见：
yang@ubuntu:~/torch$ th
______ __ | Torch7
/_ __/__ ________/ / | Scientific computing for Lua.
/ / / _ \/ __/ __/ _ \ | Type ? for help
/_/ \___/_/ \__/_//_/ | https://github.com/torch
| http://torch.ch
th>
恭喜你，安装成功！
相关链接2：
