關於在集羣上搞GCC-6.5-無權限

## 非Root用戶下編譯GCC 6.5.0

1. **下載gcc-6.5.0**

   建議先到網站上下載，然後再通過jupyter上傳到服務器。

   ```bash
   wget https://ftp.gnu.org/gnu/gcc/gcc-6.5.0/gcc-6.5.0.tar.gz
   ```

2. **解壓gcc**

   ```bash
   tar zxvf gcc-6.5.0.tar.gz
   cd gcc-6.5.0
   ```

3. **安裝依賴文件**

   ```bash
   ./contrib/download_prerequisites
   ```

4. **創建編譯目錄**

   ```bash
   cd ..
   
   mkdir gcc-6.5.0-build
   cd gcc-6.5.0-build
   ```

5. **配置並編譯**

   ```bash
   ../gcc-6.5.0/configure --disable-checking --enable-languages=c,c++ --disable-multilib --prefix=/home/jovyan/gcc6 --enable-threads=posix
   
   make -j32 && make install
   ```

6. **查看是否安裝成功**

   ```bash
   cd    # /home/jovyan/
   ./gcc6/bin/gcc -v        # 6.5.0
   ```

7. **設置環境變量**

   ```bash
   touch bashrc
   
   # Edit "bashrc" in jupyter, you can't use vi or vim via Terminal
   # Add following lines into "bashrc" and save (you can also specify your own gcc path):
   export PATH="/home/jovyan/gcc6/bin:/home/jovyan/gcc6/lib64:$PATH"
   export LD_LIBRARY_PATH="/home/jovyan/gcc6/lib:$LD_LIBRARY_PATH"
   
   # In Terminal
   mv bashrc .bashrc
   source .bashrc
   
   # Check if it works
   gcc -v    # 6.5.0
   ```