开源的UML工具，外网下载速度很慢，搬运工。
也可以直接去官网下载：
https://sourceforge.net/projects/whitestaruml/
WhiteStarUML is a fork of StarUML 5.0 providing a number of bug fixes and improving compatibility with modern operating systems.
gcc-4.8.0 gcc-4.9.0 gcc-5.1.0 gcc-6.1.0 gcc-7.1.0 gcc-8.1.0 gcc-9.1.0.7z 已验证可用，请放心下载。GCC used to stand for the GNU C Compiler, but since the compiler supports several other languages aside from C, it now stands for the GNU Compiler Collection.
