luarocks install https://raw.githubusercontent.com/szym/display/master/display-scm-0.rockspec でインストールできない問題を解決しちゃうわよ♡

pix2pixやっちゃうわよー！ってときにね、いやなことあったのよ。
```
luarocks install https://raw.githubusercontent.com/szym/display/master/display-scm-0.rockspec
```
これが実行できなかったの。
エラーはこんな感じよ。
```エラー
Using https://raw.githubusercontent.com/szym/display/master/display-scm-0.rockspec... switching to 'build' mode

Missing dependencies for display:
async >= 1.0
luasocket >= 2.0

Using https://raw.githubusercontent.com/torch/rocks/master/async-scm-1.rockspec... switching to 'build' mode
Cloning into 'async'...
remote: Enumerating objects: 210, done.
remote: Counting objects: 100% (210/210), done.
remote: Compressing objects: 100% (184/184), done.
remote: Total 210 (delta 19), reused 172 (delta 19), pack-reused 0
Receiving objects: 100% (210/210), 403.80 KiB | 19.23 MiB/s, done.
Resolving deltas: 100% (19/19), done.
make LUA_BINDIR=/home/ogino/torch/install/bin  LUA_LIBDIR=/home/ogino/torch/install/lib  LUA_INCDIR=/home/ogino/torch/install/include
basename: missing operand
Try 'basename --help' for more information.
make -C lhttp_parser  LUA= LUA_BINDIR=/home/ogino/torch/install/bin  LUA_LIBDIR=/home/ogino/torch/install/lib  LUA_INCDIR=/home/ogino/torch/install/include
make[1]: Entering directory '/tmp/luarocks_async-scm-1-3793/async/lhttp_parser'
cc -c lhttp_parser.c -o lhttp_parser.o -Ihttp-parser -I /home/ogino/torch/install/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -Wall -Werror -fPIC
CPPFLAGS=-fPIC make -C http-parser http_parser.o
make[2]: Entering directory '/tmp/luarocks_async-scm-1-3793/async/lhttp_parser/http-parser'
cc -fPIC -I. -DHTTP_PARSER_STRICT=0  -Wall -Wextra -Werror -O3  -c http_parser.c
http_parser.c: In function ‘http_parser_parse_url’:
http_parser.c:2093:18: error: this statement may fall through [-Werror=implicit-fallthrough=]
         found_at = 1;
         ~~~~~~~~~^~~
http_parser.c:2096:7: note: here
       case s_req_server:
       ^~~~
cc1: all warnings being treated as errors
Makefile:35: recipe for target 'http_parser.o' failed
make[2]: *** [http_parser.o] Error 1
make[2]: Leaving directory '/tmp/luarocks_async-scm-1-3793/async/lhttp_parser/http-parser'
Makefile:17: recipe for target 'http-parser/http_parser.o' failed
make[1]: *** [http-parser/http_parser.o] Error 2
make[1]: Leaving directory '/tmp/luarocks_async-scm-1-3793/async/lhttp_parser'
Makefile:6: recipe for target 'lhttp_parser/lhttp_parser.so' failed
make: *** [lhttp_parser/lhttp_parser.so] Error 2

Error: Failed installing dependency: https://raw.githubusercontent.com/torch/rocks/master/async-scm-1.rockspec - Build error: Failed building.
```
でも安心していいわ。解決策はあるの。
```
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
```
さぁこの状態でやっておやりなさい。
```
luarocks install https://raw.githubusercontent.com/szym/display/master/display-scm-0.rockspec
```
結果はこんな感じ♡
```結果
Using https://raw.githubusercontent.com/szym/display/master/display-scm-0.rockspec... switching to 'build' mode

Missing dependencies for display:
async >= 1.0
luasocket >= 2.0

Using https://raw.githubusercontent.com/torch/rocks/master/async-scm-1.rockspec... switching to 'build' mode
Cloning into 'async'...
remote: Enumerating objects: 210, done.
remote: Counting objects: 100% (210/210), done.
.
.
.
.
gcc -O2 -fPIC -I/home/ogino/torch/install/include -c src/unixstream.c -o src/unixstream.o -DLUASOCKET_DEBUG
gcc -shared -o socket/unix.so -L/home/ogino/torch/install/lib src/buffer.o src/compat.o src/auxiliar.o src/options.o src/timeout.o src/io.o src/usocket.o src/unix.o src/unixdgram.o src/unixstream.o
Updating manifest for /home/ogino/torch/install/lib/luarocks/rocks
luasocket 3.1.0-1 is now built and installed in /home/ogino/torch/install/ (license: MIT)

Cloning into 'display'...
remote: Enumerating objects: 28, done.
remote: Counting objects: 100% (28/28), done.
remote: Compressing objects: 100% (26/26), done.
remote: Total 28 (delta 0), reused 11 (delta 0), pack-reused 0
Unpacking objects: 100% (28/28), done.
mkdir /home/ogino/torch/install/lib/luarocks/rocks/display/scm-0/lua/display && cp -a static plugins /home/ogino/torch/install/lib/luarocks/rocks/display/scm-0/lua/display
Updating manifest for /home/ogino/torch/install/lib/luarocks/rocks
display scm-0 is now built and installed in /home/ogino/torch/install/ (license: MIT)
```
ほらね、できたでしょ。
終わりよ。